Merge branch 'master' into feat/time-zone-converter

# Conflicts:
#	app/build.gradle.kts
#	app/src/main/java/com/sadellie/unitto/UnittoNavigation.kt
#	core/base/src/main/res/values/strings.xml
#	settings.gradle.kts

FUNDING.md

@@ -1,9 +0,0 @@
-<p align="middle">
-    <img src="./content/donate.png" width="99%" />
-</p>
-
-I don't need your money, just help Unitto gain **more users**:
-- Tell your relatives
-- Tell your friends
-- Tell strangers on the streets
-- Spread the word, take over the world... or something like that

README.md

@@ -11,8 +11,7 @@
 
 ## 📲 Download
 <a href="https://play.google.com/store/apps/details?id=com.sadellie.unitto"><img alt="Google Play" src="./content/googlePlay.png" width="32%"/></a>
-<a href="https://f-droid.org/packages/com.sadellie.unitto"><img alt="F-Droid" src="./content/fDroid.png" width="32%"/></a>
-<a href="https://apps.rustore.ru/app/com.sadellie.unitto"><img alt="Rustore" src="./content/ruStore.png" width="32%"/></a>
+<a href="https://f-droid.org/packages/com.sadellie.unitto"><img alt="F-Droid" src="./content/fDroid.png" width="27%"/></a>
 
 ## 😎 Features
 - **Instant** expression evaluation
@@ -29,25 +28,21 @@
 - Customizable number **formatter**
 - **SI Standard**
 
-## 👅 Translate
-<a href="https://poeditor.com/join/project/T4zjmoq8dx" target="_blank"><img src="./content/poeditor.png" alt="Unitto - Calculate&#0032;and&#0032;convert&#0044;&#0032;but&#0032;better&#0046; | POEditor" style="width: 180px; height: 60px;" width="180" height="60" /></a>
+## 👅 [Translate](https://poeditor.com/join/project/T4zjmoq8dx)
+Join on **POEditor** to help.
 
-## 🤑 Donate
-Visit [FUNDING.md](./FUNDING.md)
+## 💡 [Open issues](https://github.com/sadellie/unitto/issues/new)
+Report bugs or request improvements. I may close your issue as not planned and reopen it later (things change).
+
+## 🎤 [Start discussions](https://github.com/sadellie/unitto/discussions/new/choose)
+If you think that your question will not fit in "Issues", start a discussion.
+
+## 👩‍💻 ~~Contribute code~~
+Code contributions are **not** welcomed. If you really want to, **ask me** first.
+
+Hard forks and alterations of Unitto are **not** welcomed. Use a "Fork" button so that commits' author is not lost.
 
 ## 🔎 Additional
-<p align="middle">
-    <a href="https://trello.com/b/cxAbRlvu/unitto" target="_blank">
-        <img src="./content/progress.png" width="99%"/>
-    </a>
-</p>
+Terms and Conditions: https://sadellie.github.io/unitto/terms
 
-<a href="https://www.producthunt.com/posts/unitto?utm_source=badge-featured&utm_medium=badge&utm_souce=badge-unitto" target="_blank"><img src="https://api.producthunt.com/widgets/embed-image/v1/featured.svg?post_id=372851&theme=light" alt="Unitto - Calculate&#0032;and&#0032;convert&#0044;&#0032;but&#0032;better&#0046; | Product Hunt" style="width: 250px; height: 54px;" width="250" height="54" /></a>
-
-Terms and Conditions, Privacy Policy, Press Kit and contact links:
-https://sadellie.github.io/unitto/
-
-## 🤓 Technical details
-- App is written in Compose
-- Multi-module architecture
-- Convention plugins for modules
+Privacy Policy: https://sadellie.github.io/unitto/privacy

app/build.gradle.kts

@@ -16,6 +16,8 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+@file:Suppress("UnstableApiUsage")
+
 plugins {
     // Basic stuff
     id("com.android.application")
@@ -26,14 +28,14 @@ plugins {
 
 android {
     namespace = "com.sadellie.unitto"
-    compileSdk = 33
+    compileSdk = 34
 
     defaultConfig {
         applicationId = "com.sadellie.unitto"
         minSdk = 21
-        targetSdk = 33
-        versionCode = 20
-        versionName = "Kobicha"
+        targetSdk = 34
+        versionCode = 22
+        versionName = "Lilac Luster"
     }
 
     buildTypes {
@@ -74,19 +76,19 @@ android {
     }
 
     compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_1_8
-        targetCompatibility = JavaVersion.VERSION_1_8
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
         isCoreLibraryDesugaringEnabled = true
     }
 
-    packagingOptions {
+    packaging {
         resources {
             excludes.add("/META-INF/{AL2.0,LGPL2.1}")
         }
     }
 
     kotlinOptions {
-        jvmTarget = "1.8"
+        jvmTarget = JavaVersion.VERSION_11.toString()
         freeCompilerArgs = freeCompilerArgs + listOf(
             "-opt-in=androidx.lifecycle.compose.ExperimentalLifecycleComposeApi"
         )
@@ -97,6 +99,12 @@ android {
     }
 }
 
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_11.toString()
+    }
+}
+
 dependencies {
     implementation(libs.androidx.core)
     coreLibraryDesugaring(libs.android.desugarJdkLibs)
@@ -112,9 +120,8 @@ dependencies {
     implementation(project(mapOf("path" to ":feature:calculator")))
     implementation(project(mapOf("path" to ":feature:settings")))
     implementation(project(mapOf("path" to ":feature:unitslist")))
-    implementation(project(mapOf("path" to ":feature:epoch")))
+    implementation(project(mapOf("path" to ":feature:datedifference")))
     implementation(project(mapOf("path" to ":feature:timezone")))
-    implementation(project(mapOf("path" to ":data:units")))
     implementation(project(mapOf("path" to ":data:model")))
     implementation(project(mapOf("path" to ":data:userprefs")))
     implementation(project(mapOf("path" to ":core:ui")))

app/src/main/java/com/sadellie/unitto/MainActivity.kt

@@ -41,10 +41,10 @@ internal class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
 
         setContent {
-            val userPrefs = userPrefsRepository.userPreferencesFlow
+            val uiPrefs = userPrefsRepository.uiPreferencesFlow
                 .collectAsStateWithLifecycle(null).value
 
-            if (userPrefs != null) UnittoApp(userPrefs)
+            if (uiPrefs != null) UnittoApp(uiPrefs)
         }
     }
 

app/src/main/java/com/sadellie/unitto/UnittoApp.kt

@@ -18,11 +18,10 @@
 
 package com.sadellie.unitto
 
+import androidx.activity.compose.BackHandler
 import androidx.compose.animation.core.tween
-import androidx.compose.material3.DrawerValue
+import androidx.compose.foundation.ExperimentalFoundationApi
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.ModalNavigationDrawer
-import androidx.compose.material3.rememberDrawerState
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.derivedStateOf
@@ -40,35 +39,44 @@ import androidx.navigation.compose.rememberNavController
 import com.google.accompanist.systemuicontroller.rememberSystemUiController
 import com.sadellie.unitto.core.base.TopLevelDestinations
 import com.sadellie.unitto.core.ui.common.UnittoDrawerSheet
+import com.sadellie.unitto.core.ui.common.UnittoModalNavigationDrawer
+import com.sadellie.unitto.core.ui.common.close
+import com.sadellie.unitto.core.ui.common.isOpen
+import com.sadellie.unitto.core.ui.common.open
+import com.sadellie.unitto.core.ui.common.rememberUnittoDrawerState
 import com.sadellie.unitto.core.ui.model.DrawerItems
 import com.sadellie.unitto.core.ui.theme.AppTypography
 import com.sadellie.unitto.core.ui.theme.DarkThemeColors
 import com.sadellie.unitto.core.ui.theme.LightThemeColors
-import com.sadellie.unitto.data.userprefs.UserPreferences
+import com.sadellie.unitto.data.userprefs.UIPreferences
 import io.github.sadellie.themmo.Themmo
 import io.github.sadellie.themmo.rememberThemmoController
 import kotlinx.coroutines.launch
 
+@OptIn(ExperimentalFoundationApi::class)
 @Composable
-internal fun UnittoApp(userPrefs: UserPreferences) {
+internal fun UnittoApp(uiPrefs: UIPreferences) {
 
     val themmoController = rememberThemmoController(
         lightColorScheme = LightThemeColors,
         darkColorScheme = DarkThemeColors,
-        // Anything below will not be called if theming mode is still loading from DataStore
-        themingMode = userPrefs.themingMode,
-        dynamicThemeEnabled = userPrefs.enableDynamicTheme,
-        amoledThemeEnabled = userPrefs.enableAmoledTheme,
-        customColor = userPrefs.customColor,
-        monetMode = userPrefs.monetMode
+        themingMode = uiPrefs.themingMode,
+        dynamicThemeEnabled = uiPrefs.enableDynamicTheme,
+        amoledThemeEnabled = uiPrefs.enableAmoledTheme,
+        customColor = uiPrefs.customColor,
+        monetMode = uiPrefs.monetMode
     )
     val navController = rememberNavController()
     val sysUiController = rememberSystemUiController()
 
     // Navigation drawer stuff
-    val drawerState = rememberDrawerState(DrawerValue.Closed)
+    val drawerState = rememberUnittoDrawerState()
     val drawerScope = rememberCoroutineScope()
-    val mainTabs = listOf(DrawerItems.Calculator, DrawerItems.Converter)
+    val mainTabs = listOf(
+        DrawerItems.Calculator,
+        DrawerItems.Converter,
+        DrawerItems.DateDifference
+    )
     val additionalTabs = listOf(DrawerItems.Settings)
 
     val navBackStackEntry by navController.currentBackStackEntryAsState()
@@ -84,14 +92,6 @@ internal fun UnittoApp(userPrefs: UserPreferences) {
                 }
         }
     }
-    val gesturesEnabled: Boolean by remember(navBackStackEntry?.destination) {
-        derivedStateOf {
-            // Will be true for routes like
-            // [null, calculator_route, settings_graph, settings_route, themes_route]
-            // We disable drawer drag gesture when we are too deep
-            navController.backQueue.size <= 4
-        }
-    }
 
     Themmo(
         themmoController = themmoController,
@@ -103,10 +103,8 @@ internal fun UnittoApp(userPrefs: UserPreferences) {
             mutableStateOf(backgroundColor.luminance() > 0.5f)
         }
 
-        ModalNavigationDrawer(
-            drawerState = drawerState,
-            gesturesEnabled = gesturesEnabled,
-            drawerContent = {
+        UnittoModalNavigationDrawer(
+            drawer = {
                 UnittoDrawerSheet(
                     modifier = Modifier,
                     mainTabs = mainTabs,
@@ -122,14 +120,23 @@ internal fun UnittoApp(userPrefs: UserPreferences) {
                         restoreState = true
                     }
                 }
+            },
+            modifier = Modifier,
+            state = drawerState,
+            gesturesEnabled = true,
+            scope = drawerScope,
+            content = {
+                UnittoNavigation(
+                    navController = navController,
+                    themmoController = it,
+                    startDestination = uiPrefs.startingScreen,
+                    openDrawer = { drawerScope.launch { drawerState.open() } }
+                )
             }
-        ) {
-            UnittoNavigation(
-                navController = navController,
-                themmoController = it,
-                startDestination = userPrefs.startingScreen,
-                openDrawer = { drawerScope.launch { drawerState.open() } }
-            )
+        )
+
+        BackHandler(drawerState.isOpen) {
+            drawerScope.launch { drawerState.close() }
         }
 
         LaunchedEffect(useDarkIcons) {

app/src/main/java/com/sadellie/unitto/UnittoNavigation.kt

@@ -23,14 +23,12 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.hilt.navigation.compose.hiltViewModel
-import androidx.navigation.NavGraph.Companion.findStartDestination
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.NavHost
 import com.sadellie.unitto.feature.calculator.navigation.calculatorScreen
 import com.sadellie.unitto.feature.converter.ConverterViewModel
 import com.sadellie.unitto.feature.converter.navigation.converterScreen
-import com.sadellie.unitto.feature.epoch.navigation.epochScreen
-import com.sadellie.unitto.feature.settings.SettingsViewModel
+import com.sadellie.unitto.feature.datedifference.navigation.dateDifferenceScreen
 import com.sadellie.unitto.feature.settings.navigation.navigateToSettings
 import com.sadellie.unitto.feature.settings.navigation.navigateToUnitGroups
 import com.sadellie.unitto.feature.settings.navigation.settingGraph
@@ -51,27 +49,16 @@ internal fun UnittoNavigation(
 ) {
     val converterViewModel: ConverterViewModel = hiltViewModel()
     val unitsListViewModel: UnitsListViewModel = hiltViewModel()
-    val settingsViewModel: SettingsViewModel = hiltViewModel()
 
     NavHost(
         navController = navController,
         startDestination = startDestination,
         modifier = Modifier.background(MaterialTheme.colorScheme.background)
     ) {
-        fun navigateToSettings() {
-            navController.navigateToSettings {
-                popUpTo(navController.graph.findStartDestination().id) {
-                    saveState = true
-                }
-                launchSingleTop = true
-                restoreState = true
-            }
-        }
-
         converterScreen(
             navigateToLeftScreen = navController::navigateToLeftSide,
             navigateToRightScreen = navController::navigateToRightSide,
-            navigateToSettings = ::navigateToSettings,
+            navigateToSettings = navController::navigateToSettings,
             navigateToMenu = openDrawer,
             viewModel = converterViewModel
         )
@@ -91,7 +78,6 @@ internal fun UnittoNavigation(
         )
 
         settingGraph(
-            settingsViewModel = settingsViewModel,
             themmoController = themmoController,
             navController = navController,
             menuButtonClick = openDrawer
@@ -99,14 +85,17 @@ internal fun UnittoNavigation(
 
         calculatorScreen(
             navigateToMenu = openDrawer,
-            navigateToSettings = ::navigateToSettings
+            navigateToSettings = navController::navigateToSettings
         )
 
-        epochScreen(navigateToMenu = openDrawer)
+        dateDifferenceScreen(
+            navigateToMenu = openDrawer,
+            navigateToSettings = navController::navigateToSettings
+        )
 
         timeZoneScreen(
             navigateToMenu = openDrawer,
-            navigateToSettings = ::navigateToSettings
+            navigateToSettings = navController::navigateToSettings
         )
     }
 }

build-logic/convention/build.gradle.kts

@@ -27,6 +27,12 @@ java {
     targetCompatibility = JavaVersion.VERSION_11
 }
 
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_11.toString()
+    }
+}
+
 dependencies {
     compileOnly(libs.android.gradlePlugin)
     compileOnly(libs.kotlin.gradlePlugin)

build-logic/convention/src/main/java/UnittoHiltPlugin.kt

@@ -22,6 +22,7 @@ import org.gradle.api.artifacts.VersionCatalogsExtension
 import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.getByType
 
+@Suppress("UNUSED")
 class UnittoHiltPlugin : Plugin<Project> {
     override fun apply(target: Project) {
         with(target) {

build-logic/convention/src/main/java/UnittoLibraryComposePlugin.kt

@@ -25,6 +25,7 @@ import org.gradle.kotlin.dsl.configure
 import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.getByType
 
+@Suppress("UNUSED")
 class UnittoLibraryComposePlugin : Plugin<Project> {
     override fun apply(target: Project) {
         with(target) {

build-logic/convention/src/main/java/UnittoLibraryFeaturePlugin.kt

@@ -22,6 +22,7 @@ import org.gradle.api.artifacts.VersionCatalogsExtension
 import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.getByType
 
+@Suppress("UNUSED")
 class UnittoLibraryFeaturePlugin : Plugin<Project> {
     override fun apply(target: Project) {
         with(target) {

build-logic/convention/src/main/java/UnittoLibraryPlugin.kt

@@ -25,6 +25,7 @@ import org.gradle.kotlin.dsl.configure
 import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.getByType
 
+@Suppress("UNUSED")
 class UnittoLibraryPlugin : Plugin<Project> {
     override fun apply(target: Project) {
         with(target) {

build-logic/convention/src/main/java/com/sadellie/unitto/ConfigureCompose.kt

@@ -23,6 +23,7 @@ import org.gradle.api.Project
 import org.gradle.api.artifacts.VersionCatalogsExtension
 import org.gradle.kotlin.dsl.getByType
 
+@Suppress("UnstableApiUsage")
 internal fun Project.configureCompose(
     commonExtension: CommonExtension<*, *, *, *>,
 ) {

build-logic/convention/src/main/java/com/sadellie/unitto/ConfigureKotlinAndroid.kt

@@ -25,13 +25,16 @@ import org.gradle.api.artifacts.VersionCatalogsExtension
 import org.gradle.api.plugins.ExtensionAware
 import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.getByType
+import org.gradle.kotlin.dsl.withType
 import org.jetbrains.kotlin.gradle.dsl.KotlinJvmOptions
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
+@Suppress("UnstableApiUsage")
 internal fun Project.configureKotlinAndroid(
     commonExtension: CommonExtension<*, *, *, *>,
 ) {
     commonExtension.apply {
-        compileSdk = 33
+        compileSdk = 34
 
         defaultConfig {
             minSdk = 21
@@ -45,8 +48,8 @@ internal fun Project.configureKotlinAndroid(
         }
 
         compileOptions {
-            sourceCompatibility = JavaVersion.VERSION_1_8
-            targetCompatibility = JavaVersion.VERSION_1_8
+            sourceCompatibility = JavaVersion.VERSION_11
+            targetCompatibility = JavaVersion.VERSION_11
             isCoreLibraryDesugaringEnabled = true
         }
 
@@ -59,7 +62,7 @@ internal fun Project.configureKotlinAndroid(
             resValues = false
         }
 
-        packagingOptions {
+        packaging {
             resources {
                 excludes.add("/META-INF/{AL2.0,LGPL2.1}")
             }
@@ -73,7 +76,14 @@ internal fun Project.configureKotlinAndroid(
                 "-opt-in=androidx.compose.ui.unit.ExperimentalUnitApi",
                 "-opt-in=androidx.lifecycle.compose.ExperimentalLifecycleComposeApi"
             )
-            jvmTarget = JavaVersion.VERSION_1_8.toString()
+            jvmTarget = JavaVersion.VERSION_11.toString()
+        }
+    }
+
+    tasks.withType<KotlinCompile>().configureEach {
+        kotlinOptions {
+            // Set JVM target to 11
+            jvmTarget = JavaVersion.VERSION_11.toString()
         }
     }
 

build-logic/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +0,0 @@
-distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
-distributionPath=wrapper/dists
-zipStorePath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME

build-logic/settings.gradle.kts

@@ -16,6 +16,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+@Suppress("UnstableApiUsage")
 dependencyResolutionManagement {
     repositories {
         google()

core/base/build.gradle.kts

@@ -16,6 +16,8 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+@file:Suppress("UnstableApiUsage")
+
 plugins {
     id("unitto.library")
 }

core/base/src/main/java/com/sadellie/unitto/core/base/OutputFormat.kt

@@ -29,14 +29,3 @@ object OutputFormat {
     // App will try it's best to use engineering notation
     const val FORCE_ENGINEERING = 2
 }
-
-/**
- * Available formats. Used in settings
- */
-val OUTPUT_FORMAT: Map<Int, Int> by lazy {
-    mapOf(
-        OutputFormat.PLAIN to R.string.plain,
-        OutputFormat.ALLOW_ENGINEERING to R.string.allow_engineering,
-        OutputFormat.FORCE_ENGINEERING to R.string.force_engineering,
-    )
-}

core/base/src/main/java/com/sadellie/unitto/core/base/Precision.kt

@@ -22,28 +22,3 @@ package com.sadellie.unitto.core.base
  * Current maximum scale that will be used in app. Used in various place in code
  */
 const val MAX_PRECISION: Int = 1_000
-
-/**
- * Currently available scale options
- */
-val PRECISIONS: Map<Int, Int> by lazy {
-    mapOf(
-        0 to R.string.precision_zero,
-        1 to R.string.precision_one,
-        2 to R.string.precision_two,
-        3 to R.string.precision_three,
-        4 to R.string.precision_four,
-        5 to R.string.precision_five,
-        6 to R.string.precision_six,
-        7 to R.string.precision_seven,
-        8 to R.string.precision_eight,
-        9 to R.string.precision_nine,
-        10 to R.string.precision_ten,
-        11 to R.string.precision_eleven,
-        12 to R.string.precision_twelve,
-        13 to R.string.precision_thirteen,
-        14 to R.string.precision_fourteen,
-        15 to R.string.precision_fifteen,
-        MAX_PRECISION to R.string.max_precision
-    )
-}

core/base/src/main/java/com/sadellie/unitto/core/base/Separator.kt

@@ -22,18 +22,7 @@ package com.sadellie.unitto.core.base
  * Separators mean symbols that separate fractional part
  */
 object Separator {
-    const val SPACES = 0
+    const val SPACE = 0
     const val PERIOD = 1
     const val COMMA = 2
 }
-
-/**
- * Map of separators that is used in settings
- */
-val SEPARATORS: Map<Int, Int> by lazy {
-    mapOf(
-        Separator.SPACES to R.string.spaces,
-        Separator.PERIOD to R.string.period,
-        Separator.COMMA to R.string.comma
-    )
-}

core/base/src/main/java/com/sadellie/unitto/core/base/Token.kt

@@ -19,103 +19,126 @@
 package com.sadellie.unitto.core.base
 
 object Token {
-    const val _1 = "1"
-    const val _2 = "2"
-    const val _3 = "3"
-    const val _4 = "4"
-    const val _5 = "5"
-    const val _6 = "6"
-    const val _7 = "7"
-    const val _8 = "8"
-    const val _9 = "9"
-    const val _0 = "0"
+    object Digit {
+        const val _1 = "1"
+        const val _2 = "2"
+        const val _3 = "3"
+        const val _4 = "4"
+        const val _5 = "5"
+        const val _6 = "6"
+        const val _7 = "7"
+        const val _8 = "8"
+        const val _9 = "9"
+        const val _0 = "0"
+        const val dot = "."
 
-    const val baseA = "A"
-    const val baseB = "B"
-    const val baseC = "C"
-    const val baseD = "D"
-    const val baseE = "E"
-    const val baseF = "F"
-
-    const val dot = "."
-    const val comma = ","
-    const val E = "E"
-
-    const val plus = "+"
-    const val minus = "-"
-    const val minusDisplay = "–"
-
-    const val divide = "/"
-    const val divideDisplay = "÷"
-
-    const val multiply = "*"
-    const val multiplyDisplay = "×"
-
-    const val leftBracket = "("
-    const val rightBracket = ")"
-    const val exponent = "^"
-    const val sqrt = "√"
-    const val pi = "π"
-    const val factorial = "!"
-    const val sin = "sin("
-    const val arSin = "arsin("
-    const val cos = "cos("
-    const val arCos = "arcos("
-    const val tan = "tan("
-    const val acTan = "actan("
-    const val e = "e"
-    const val exp = "exp("
-    const val modulo = "#"
-    const val ln = "ln("
-    const val log = "log("
-    const val percent = "%"
-
-    val operators by lazy {
-        listOf(
-            plus,
-            minus,
-            minusDisplay,
-            multiply,
-            multiplyDisplay,
-            divide,
-            divideDisplay,
-            sqrt,
-            exponent,
-        )
+        val all by lazy {
+            listOf(_1, _2, _3, _4, _5, _6, _7, _8, _9, _0)
+        }
+        val allWithDot by lazy { all + dot }
     }
 
-    val digits by lazy {
-        listOf(
-            _1,
-            _2,
-            _3,
-            _4,
-            _5,
-            _6,
-            _7,
-            _8,
-            _9,
-            _0,
-        )
+    object Letter {
+        const val _A = "A"
+        const val _B = "B"
+        const val _C = "C"
+        const val _D = "D"
+        const val _E = "E"
+        const val _F = "F"
+
+        val all by lazy {
+            listOf(_A, _B, _C, _D, _E, _F)
+        }
     }
 
-    val internalToDisplay: Map<String, String> = hashMapOf(
-        minus to minusDisplay,
-        multiply to multiplyDisplay,
-        divide to divideDisplay
-    )
+    object Operator {
+        const val plus = "+"
+        const val minus = "−"
+        const val multiply = "×"
+        const val divide = "÷"
+        const val leftBracket = "("
+        const val rightBracket = ")"
+        const val power = "^"
+        const val factorial = "!"
+        const val modulo = "#"
+        const val percent = "%"
+        const val sqrt = "√"
 
-    val knownSymbols: List<String> by lazy {
-        listOf(
-            arSin, arCos, acTan, exp,
-            sin, cos, tan, ln, log,
-            leftBracket, rightBracket,
-            exponent, sqrt, factorial,
-            modulo, e, percent, pi,
-            multiply, multiplyDisplay,
-            plus, minus, minusDisplay, divide, divideDisplay,
-            baseA, baseB, baseC, baseD, baseE, baseF,
-            _1, _2, _3, _4, _5, _6, _7, _8, _9, _0
-        ).sortedByDescending { it.length }
+        val all by lazy {
+            listOf(
+                plus, minus, multiply, divide,
+                leftBracket, rightBracket,
+                power, factorial, modulo, percent, sqrt,
+            )
+        }
+    }
+
+    object Func {
+        const val sin = "sin"
+        const val sinBracket = "$sin("
+        const val cos = "cos"
+        const val cosBracket = "$cos("
+        const val tan = "tan"
+        const val tanBracket = "$tan("
+        const val arsin = "sin⁻¹"
+        const val arsinBracket = "$arsin("
+        const val arcos = "cos⁻¹"
+        const val arcosBracket = "$arcos("
+        const val actan = "tan⁻¹"
+        const val actanBracket = "$actan("
+        const val ln = "ln"
+        const val lnBracket = "$ln("
+        const val log = "log"
+        const val logBracket = "$log("
+        const val exp = "exp"
+        const val expBracket = "$exp("
+
+        val all by lazy {
+            listOf(
+                arsin, arcos, actan, sin, cos, tan, log, exp, ln
+            ).sortedByDescending { it.length }
+        }
+
+        val allWithOpeningBracket by lazy {
+            listOf(
+                arsinBracket, arcosBracket, actanBracket, sinBracket, cosBracket, tanBracket,
+                logBracket, expBracket, lnBracket
+            )
+        }
+    }
+
+    object Const {
+        const val pi = "π"
+        const val e = "e"
+
+        val all by lazy {
+            listOf(pi, e)
+        }
+    }
+
+    // Used only in formatter, don't use internally
+    object DisplayOnly {
+        const val comma = ","
+        const val engineeringE = "E"
+        const val minus = "−"
+    }
+
+    val expressionTokens by lazy {
+        Digit.allWithDot + Operator.all + Func.all + Const.all
+    }
+
+    val numberBaseTokens by lazy {
+        Digit.all + Letter.all
+    }
+
+    val sexyToUgly by lazy {
+        mapOf(
+            Operator.minus to listOf("-", "–", "—", "—"),
+            Operator.divide to listOf("/"),
+            Operator.multiply to listOf("*", "•"),
+            Func.arsin to listOf("arsin"),
+            Func.arcos to listOf("arcos"),
+            Func.actan to listOf("actan")
+        )
     }
 }

core/base/src/main/java/com/sadellie/unitto/core/base/TopLevelDestinations.kt

@@ -34,9 +34,9 @@ sealed class TopLevelDestinations(
         name = R.string.calculator
     )
 
-    object Epoch : TopLevelDestinations(
-        route = "epoch_route",
-        name = R.string.epoch_converter
+    object DateDifference : TopLevelDestinations(
+        route = "date_difference_route",
+        name = R.string.date_difference
     )
 
     object TimeZone : TopLevelDestinations(

core/base/src/main/res/values-de/strings.xml

@@ -377,7 +377,7 @@
     <string name="attopascal_short">aPa</string>
     <string name="femtopascal">Femtopascal</string>
     <string name="femtopascal_short">fPa</string>
-    <string name="picopascal">Picopascal</string>
+    <string name="picopascal">Pikopascal</string>
     <string name="picopascal_short">pPa</string>
     <string name="nanopascal">Nanopascal</string>
     <string name="nanopascal_short">nPa</string>
@@ -421,7 +421,7 @@
     <string name="attometer_per_square_second_short">am/s^2</string>
     <string name="femtometer_per_square_second">Femtometer pro Quadratsekunde</string>
     <string name="femtometer_per_square_second_short">fm/s^2</string>
-    <string name="picometer_per_square_second">Picometer pro Quadratsekunde</string>
+    <string name="picometer_per_square_second">Pikometer pro Quadratsekunde</string>
     <string name="picometer_per_square_second_short">pm/s^2</string>
     <string name="nanometer_per_square_second">Nanometer pro Quadratsekunde</string>
     <string name="nanometer_per_square_second_short">mm/s^2</string>
@@ -659,7 +659,9 @@
     <string name="theme_setting">Farbthemen</string>
     <string name="precision_setting">Präzision</string>
     <string name="separator_setting">Trennzeichen</string>
-    <string name="output_format_setting">Ausgabeformate</string>
+
+    <!-- Fuzzy -->
+    <string name="exponential_notation_setting">Exponentielle Notation</string>
     <string name="unit_groups_setting">Einheitengruppen</string>
     <string name="currency_rates_note_setting">Falsche Wechselkurse</string>
     <string name="currency_rates_note_title">Hinweis </string>
@@ -668,29 +670,29 @@
     <string name="privacy_policy">Datenschutz-Bestimmungen </string>
     <string name="third_party_licenses">Richtlinien von Drittanbietern </string>
     <string name="rate_this_app">Diese App bewerten</string>
+    <string name="formatting_setting">Formatierung</string>
     <string name="additional_settings_group">Zusätzliches</string>
 
     <!-- Precision -->
     <string name="precision_setting_support">Anzahl der Dezimalstellen</string>
     <string name="precision_setting_info">Umgerechnete Werte können eine höhere Präzision als eingestellt haben.</string>
-    <string name="max_precision">1 000 (Maximum)</string>
+    <string name="max_precision">%1$s (Maximum)</string>
 
     <!-- Separator -->
     <string name="separator_setting_support">Gruppentrennzeichen</string>
-    <string name="period">Punkt (42.069,12)</string>
-    <string name="comma">Komma (42,069.12)</string>
-    <string name="spaces">Leerzeichen (42 069.12)</string>
+    <string name="period">Punkt</string>
+    <string name="comma">Komma</string>
+
+    <!-- Fuzzy -->
+    <string name="space">Leerzeichen</string>
 
     <!-- Output format -->
-    <string name="output_format_setting_support">Ergebnisformatierung</string>
-    <string name="output_format_setting_info">Wissenschaftliche Notation sieht wie 1E-21 aus</string>
-    <string name="plain">Standard</string>
-    <string name="allow_engineering">Wissenschaftliche Notation erlauben</string>
-    <string name="force_engineering">Wissenschaftliche Notation erzwingen</string>
+    <!-- Fuzzy -->
+    <string name="exponential_notation_setting_support">Einen Teil der Nummer durch E ersetzen</string>
 
     <!-- Theme -->
     <string name="theme_setting_support">App Aussehen</string>
-    <string name="force_auto_mode">Automatisch</string>
+    <string name="auto_label">Automatisch</string>
     <string name="force_light_mode">Hell</string>
     <string name="force_dark_mode">Dunkel</string>
     <string name="color_theme">Farbthema</string>
@@ -726,4 +728,415 @@
     <string name="reorder_unit_group_description">Einheitengruppe umordnen</string>
     <string name="disable_unit_group_description">Einheitengruppe deaktivieren</string>
     <string name="app_version_name_setting">Versionsname</string>
+    <string name="about_unitto">Über Unitto</string>
+    <string name="about_unitto_support">Mehr über die App erfahren</string>
+    <string name="unit_groups_support">Einheiten deaktivieren und anordnen</string>
+    <string name="cent">Cent</string>
+    <string name="cent_short">cent</string>
+
+    <!-- Flux -->
+    <string name="maxwell">Maxwell</string>
+    <string name="maxwell_short">Mx</string>
+    <string name="weber">Weber</string>
+    <string name="weber_short">Wb</string>
+    <string name="milliweber">Milliweber</string>
+    <string name="milliweber_short">mWb</string>
+    <string name="microweber">Microweber</string>
+    <string name="microweber_short">μWb</string>
+    <string name="kiloweber">Kiloweber</string>
+    <string name="kiloweber_short">kWb</string>
+    <string name="megaweber">Megaweber</string>
+    <string name="megaweber_short">MWb</string>
+    <string name="gigaweber">Gigaweber</string>
+    <string name="gigaweber_short">GWb</string>
+    <string name="flux">Flux</string>
+    <string name="open_source">Quellcode anzeigen</string>
+    <string name="translate_app">Diese App übersetzen</string>
+    <string name="translate_app_support">Dem POEditor-Projekt beitreten und helfen</string>
+
+    <!-- Number base -->
+    <string name="binary">Binär</string>
+    <string name="binary_short">base2</string>
+    <string name="ternary">Ternär</string>
+    <string name="ternary_short">base3</string>
+    <string name="quaternary">Quartär</string>
+    <string name="quaternary_short">base4</string>
+    <string name="quinary">Quinär</string>
+    <string name="quinary_short">base5</string>
+    <string name="senary">Senär</string>
+    <string name="senary_short">base6</string>
+    <string name="septenary">Septenär</string>
+    <string name="septenary_short">base7</string>
+    <string name="octal">Oktal</string>
+    <string name="octal_short">base8</string>
+    <string name="nonary">Nonär</string>
+    <string name="nonary_short">base9</string>
+    <string name="decimal">Dezimal</string>
+    <string name="decimal_short">base10</string>
+    <string name="undecimal">Undezimal</string>
+    <string name="undecimal_short">base11</string>
+    <string name="duodecimal">Duodezimal</string>
+    <string name="duodecimal_short">base12</string>
+    <string name="tridecimal">Tridezimal</string>
+    <string name="tridecimal_short">base13</string>
+    <string name="tetradecimal">Tetradezimal</string>
+    <string name="tetradecimal_short">base14</string>
+    <string name="pentadecimal">Pentadezimal</string>
+    <string name="pentadecimal_short">base15</string>
+    <string name="hexadecimal">Hexadezimal</string>
+    <string name="hexadecimal_short">base16</string>
+    <string name="number_base">Basis</string>
+    <string name="enable_vibrations">Vibrationen</string>
+    <string name="enable_vibrations_support">Haptisches Feedback für Tastaturtasten</string>
+    <string name="millibar">Millibar</string>
+    <string name="millibar_short">mbar</string>
+    <string name="kilopascal">Kilopascal</string>
+    <string name="kilopascal_short">kPa</string>
+    <string name="micron_of_mercury">Mikrometer Quecksilber</string>
+    <string name="micron_of_mercury_short">μmHg</string>
+
+    <!-- Tools -->
+    <!-- Fuzzy -->
+    <string name="epoch_converter">Epochkonverter</string>
+
+    <!-- Calculator -->
+    <string name="calculator">Taschenrechner</string>
+
+    <!-- Epoch -->
+    <string name="year_short">y</string>
+    <string name="month_short">m</string>
+    <string name="nautical_mile">Nautische Meile</string>
+    <string name="nautical_mile_short">M</string>
+    <string name="starting_screen_setting">Startbildschirm</string>
+    <string name="starting_screen_setting_support">Wählen Sie, welcher Bildschirm beim Starten der App angezeigt wird</string>
+
+    <!-- Tools -->
+    <string name="unit_converter">Einheitenumrechner</string>
+    <string name="calculator_clear_history_label">Leeren</string>
+    <string name="calculator_clear_history_title">Verlauf leeren</string>
+    <string name="calculator_clear_history_support">Alle Ausdrücke aus dem Verlauf werden für immer gelöscht. Diese Aktion kann nicht rückgängig gemacht werden!</string>
+    <string name="calculator_no_history">Kein Verlauf</string>
+    <string name="open_menu_description">Menü öffnen</string>
+    <string name="microgram">Mikrogramm</string>
+    <string name="microgram_short">µg</string>
+
+    <!-- ELECTROSTATIC CAPACITANCE -->
+    <string name="attofarad">Attofarad</string>
+    <string name="attofarad_short">aF</string>
+    <string name="statfarad">Statfarad</string>
+    <string name="statfarad_short">stF</string>
+    <string name="farad">Farad</string>
+    <string name="farad_short">F</string>
+    <string name="exafarad">Exafarad</string>
+    <string name="exafarad_short">EF</string>
+    <string name="picofarad">Pikofarad</string>
+    <string name="picofarad_short">pF</string>
+    <string name="nanofarad">Nanofarad</string>
+    <string name="nanofarad_short">nF</string>
+    <string name="microfarad">Microfarad</string>
+    <string name="microfarad_short">µF</string>
+    <string name="millifarad">Millifarad</string>
+    <string name="millifarad_short">mF</string>
+    <string name="kilofarad">Kilofarad</string>
+    <string name="kilofarad_short">kF</string>
+    <string name="megafarad">Megafarad</string>
+    <string name="megafarad_short">MF</string>
+    <string name="gigafarad">Gigafarad</string>
+    <string name="gigafarad_short">GF</string>
+    <string name="petafarad">Petafarad</string>
+    <string name="petafarad_short">PF</string>
+
+    <!-- Prefixes -->
+    <string name="prefix_quetta">Quetta</string>
+    <string name="prefix_quetta_short">Q</string>
+    <string name="prefix_ronna">Ronna</string>
+    <string name="prefix_ronna_short">R</string>
+    <string name="prefix_yotta">Yotta</string>
+    <string name="prefix_yotta_short">Y</string>
+    <string name="prefix_zetta">Zetta</string>
+    <string name="prefix_zetta_short">Z</string>
+    <string name="prefix_exa">Exa</string>
+    <string name="prefix_exa_short">E</string>
+    <string name="prefix_peta">Peta</string>
+    <string name="prefix_peta_short">P</string>
+    <string name="prefix_tera">Tera</string>
+    <string name="prefix_tera_short">T</string>
+    <string name="prefix_giga">Giga</string>
+    <string name="prefix_giga_short">G</string>
+    <string name="prefix_mega">Mega</string>
+    <string name="prefix_mega_short">M</string>
+    <string name="prefix_kilo">Kilo</string>
+    <string name="prefix_kilo_short">k</string>
+    <string name="prefix_hecto">Hekto</string>
+    <string name="prefix_hecto_short">h</string>
+    <string name="prefix_deca">Deka</string>
+    <string name="prefix_deca_short">da</string>
+    <string name="prefix_base">Basis</string>
+    <string name="prefix_base_short">Basis</string>
+    <string name="prefix_deci">Dezi</string>
+    <string name="prefix_deci_short">d</string>
+    <string name="prefix_centi">Zenti</string>
+    <string name="prefix_centi_short">c</string>
+    <string name="prefix_milli">Milli</string>
+    <string name="prefix_milli_short">m</string>
+    <string name="prefix_micro">Micro</string>
+    <string name="prefix_micro_short">μ</string>
+    <string name="prefix_nano">Nano</string>
+    <string name="prefix_nano_short">n</string>
+    <string name="prefix_pico">Piko</string>
+    <string name="prefix_pico_short">P</string>
+    <string name="prefix_femto">Femto</string>
+    <string name="prefix_femto_short">f</string>
+    <string name="prefix_atto">Atto</string>
+    <string name="prefix_atto_short">a</string>
+    <string name="prefix_zepto">Zepto</string>
+    <string name="prefix_zepto_short">z</string>
+    <string name="prefix_yocto">Yokto</string>
+    <string name="prefix_yocto_short">y</string>
+    <string name="prefix_ronto">Ronto</string>
+    <string name="prefix_ronto_short">r</string>
+    <string name="prefix_quecto">Quekto</string>
+    <string name="prefix_quecto_short">q</string>
+
+    <!-- Force -->
+    <string name="newton">Newton</string>
+    <string name="newton_short">N</string>
+    <string name="kilonewton">Kilonewton</string>
+    <string name="kilonewton_short">kN</string>
+
+    <!-- Fuzzy -->
+    <string name="gram_force">Gramm-Kraft</string>
+    <string name="gram_force_short">gf</string>
+
+    <!-- Fuzzy -->
+    <string name="kilogram_force">Kilogramm-Kraft</string>
+    <string name="kilogram_force_short">kgf</string>
+    <string name="ton_force">Tonnen-Kraft</string>
+    <string name="ton_force_short">tf</string>
+    <string name="millinewton">Millinewton</string>
+    <string name="millinewton_short">mN</string>
+    <string name="attonewton">Attonewton</string>
+    <string name="attonewton_short">aN</string>
+    <string name="dyne">Dyn</string>
+    <string name="dyne_short">dyn</string>
+    <string name="joule_per_meter">Joule/Meter</string>
+    <string name="joule_per_meter_short">J/m</string>
+    <string name="joule_per_centimeter">Joule/Zentimeter</string>
+    <string name="joule_per_centimeter_short">J/cm</string>
+    <string name="kilopound_force">Kilopfund-Kraft</string>
+    <string name="kilopound_force_short">kipf</string>
+    <string name="pound_force">Pfund-Kraft</string>
+    <string name="pound_force_short">lbf</string>
+    <string name="ounce_force">Unzen-Kraft</string>
+    <string name="ounce_force_short">ozf</string>
+    <string name="pond">Pond</string>
+    <string name="pond_short">p</string>
+
+    <!-- Fuzzy -->
+    <string name="kilopond">Kilopond</string>
+    <string name="kilopond_short">kp</string>
+
+    <!-- Torque -->
+    <string name="newton_meter">Newtonmeter</string>
+    <string name="newton_meter_short">N*m</string>
+    <string name="newton_centimeter">Newtonzentimeter</string>
+    <string name="newton_centimeter_short">N*cm</string>
+    <string name="newton_millimeter">Newtonmillimeter</string>
+    <string name="newton_millimeter_short">N*mm</string>
+    <string name="kilonewton_meter">Kilonewtonmeter</string>
+    <string name="kilonewton_meter_short">kN*m</string>
+    <string name="dyne_meter">Dynmeter</string>
+    <string name="dyne_meter_short">dyn*m</string>
+
+    <!-- Fuzzy -->
+    <string name="dyne_centimeter">Dynzentimeter</string>
+    <string name="dyne_centimeter_short">dyn*cm</string>
+
+    <!-- Fuzzy -->
+    <string name="dyne_millimeter">Dynmillimeter</string>
+    <string name="dyne_millimeter_short">dyn*mm</string>
+
+    <!-- Fuzzy -->
+    <string name="kilogram_force_meter">Kilogramm-Kraft-Meter</string>
+    <string name="kilogram_force_meter_short">kgf*m</string>
+
+    <!-- Fuzzy -->
+    <string name="kilogram_force_centimeter">Kilogramm-Kraft-Zentimeter</string>
+    <string name="kilogram_force_centimeter_short">kgf*cm</string>
+
+    <!-- Fuzzy -->
+    <string name="kilogram_force_millimeter">Kilogramm-Kraft-Millimeter</string>
+    <string name="kilogram_force_millimeter_short">kgf*mm</string>
+
+    <!-- Fuzzy -->
+    <string name="gram_force_meter">Gramm-Kraft Meter</string>
+    <string name="gram_force_meter_short">gf*m</string>
+
+    <!-- Fuzzy -->
+    <string name="gram_force_centimeter">Gramm-Kraft Zentimeter</string>
+    <string name="gram_force_centimeter_short">gf*cm</string>
+
+    <!-- Fuzzy -->
+    <string name="gram_force_millimeter">Gramm-Kraft Millimeter</string>
+    <string name="gram_force_millimeter_short">gf*mm</string>
+
+    <!-- Fuzzy -->
+    <string name="ounce_force_foot">Unzen-Kraft-Fuß</string>
+    <string name="ounce_force_foot_short">ozf*ft</string>
+
+    <!-- Fuzzy -->
+    <string name="ounce_force_inch">Unze-Kraft-Zoll</string>
+    <string name="ounce_force_inch_short">ozf*in</string>
+    <string name="pound_force_foot">Pfund-Kraft-Fuß</string>
+    <string name="pound_force_foot_short">lbf*ft</string>
+
+    <!-- Fuzzy -->
+    <string name="pound_force_inch">Pfund-Kraft-Zoll</string>
+    <string name="pound_force_inch_short">lbf*in</string>
+
+    <!-- Flow rate -->
+    <string name="liter_per_hour">Liter/Stunde</string>
+    <string name="liter_per_hour_short">L/h</string>
+    <string name="liter_per_minute">Liter/Minute</string>
+    <string name="liter_per_minute_short">L/m</string>
+    <string name="liter_per_second">Liter/Sekunde</string>
+    <string name="liter_per_second_short">L/s</string>
+    <string name="milliliter_per_hour">Milliliter/Stunde</string>
+    <string name="milliliter_per_hour_short">mL/h</string>
+    <string name="milliliter_per_minute">Milliliter/Minute</string>
+    <string name="milliliter_per_minute_short">mL/m</string>
+    <string name="milliliter_per_second">Milliliter/Sekunde</string>
+    <string name="milliliter_per_second_short">mL/s</string>
+    <string name="cubic_meter_per_hour">Kubikmeter/Stunde</string>
+    <string name="cubic_meter_per_hour_short">m3/h</string>
+    <string name="cubic_meter_per_minute">Kubikmeter/Minute</string>
+    <string name="cubic_meter_per_minute_short">m3/m</string>
+    <string name="cubic_meter_per_second">Kubikmeter/Sekunde</string>
+    <string name="cubic_meter_per_second_short">m3/s</string>
+    <string name="cubic_millimeter_per_hour">Kubikmillimeter/Stunde</string>
+    <string name="cubic_millimeter_per_hour_short">mm3/h</string>
+    <string name="cubic_millimeter_per_minute">Kubikmillimeter/Minute</string>
+    <string name="cubic_millimeter_per_minute_short">mm3/m</string>
+    <string name="cubic_millimeter_per_second">Kubikmillimeter/Sekunde</string>
+    <string name="cubic_millimeter_per_second_short">mm3/s</string>
+    <string name="cubic_foot_per_hour">Kubikfuß/Stunde</string>
+    <string name="cubic_foot_per_hour_short">ft3/h</string>
+    <string name="cubic_foot_per_minute">Kubikfuß/Minute</string>
+    <string name="cubic_foot_per_minute_short">ft3/m</string>
+    <string name="cubic_foot_per_second">Kubikfuß/Sekunde</string>
+    <string name="cubic_foot_per_second_short">ft3/s</string>
+    <string name="gallon_per_hour_us">Gallone/Stunde (U.S.)</string>
+    <string name="gallon_per_hour_us_short">gal/h</string>
+    <string name="gallon_per_minute_us">Gallone/Minute(U.S.)</string>
+    <string name="gallon_per_minute_us_short">gal/m</string>
+    <string name="gallon_per_second_us">Gallone/Sekunde(U.S.)</string>
+    <string name="gallon_per_second_us_short">gal/s</string>
+    <string name="gallon_per_hour_imperial">Gallone/Stunde (Imperial)</string>
+    <string name="gallon_per_hour_imperial_short">gal/h</string>
+    <string name="gallon_per_minute_imperial">Gallone/Minute(Imperial)</string>
+    <string name="gallon_per_minute_imperial_short">gal/m</string>
+    <string name="gallon_per_second_imperial">Gallone/Sekunde(Imperial)</string>
+    <string name="gallon_per_second_imperial_short">gal/s</string>
+
+    <!-- Luminance -->
+    <string name="candela_per_square_meter">Candela/Quadratmeter</string>
+    <string name="candela_per_square_meter_short">cd/m^2</string>
+    <string name="candela_per_square_centimeter">Candela/Quadratzentimeter</string>
+    <string name="candela_per_square_centimeter_short">cd/cm^2</string>
+    <string name="candela_per_square_foot">Candela/Quadratfuß</string>
+    <string name="candela_per_square_foot_short">cd/ft^2</string>
+    <string name="candela_per_square_inch">Candela/Quadratzoll</string>
+    <string name="candela_per_square_inch_short">cd/in^2</string>
+    <string name="kilocandela_per_square_meter">Kilocandela/Quadratmeter</string>
+    <string name="kilocandela_per_square_meter_short">kcd</string>
+    <string name="stilb">Stilb</string>
+    <string name="stilb_short">sb</string>
+    <string name="lumen_per_square_meter_per_steradian">Lumen/Quadratmeter/Steradiant</string>
+    <string name="lumen_per_square_meter_per_steradian_short">lm/m^2/sr</string>
+    <string name="lumen_per_square_centimeter_per_steradian">Lumen/Quadratzentimeter/Steradian</string>
+    <string name="lumen_per_square_centimeter_per_steradian_short">lm/cm^2/sr</string>
+    <string name="lumen_per_square_foot_per_steradian">Lumen/Quadratfuß/Steradian</string>
+    <string name="lumen_per_square_foot_per_steradian_short">lm/ft^2/sr</string>
+    <string name="watt_per_square_centimeter_per_steradian">Watt/Quadratzentimeter/Steradian</string>
+    <string name="watt_per_square_centimeter_per_steradian_short">W/cm^2/sr</string>
+    <string name="nit">Nit</string>
+    <string name="nit_short">nt</string>
+    <string name="millinit">Millinit</string>
+    <string name="millinit_short">mnt</string>
+    <string name="lambert">Lambert</string>
+    <string name="lambert_short">L</string>
+    <string name="millilambert">Millilambert</string>
+    <string name="millilambert_short">mL</string>
+    <string name="foot_lambert">Fuß-Lambert</string>
+    <string name="foot_lambert_short">fL</string>
+    <string name="apostilb">Apostilb</string>
+    <string name="apostilb_short">asb</string>
+    <string name="blondel">Blondel</string>
+    <string name="blondel_short">blondel</string>
+    <string name="bril">Bril</string>
+    <string name="bril_short">bril</string>
+    <string name="skot">Skot</string>
+    <string name="skot_short">sk</string>
+    <string name="electrostatic_capacitance">Kapazität</string>
+    <string name="prefix">Präfix</string>
+    <string name="force">Kraft</string>
+    <string name="torque">Drehmoment</string>
+
+    <!-- Fuzzy -->
+    <string name="flow_rate">Fluss</string>
+    <string name="luminance">Leuchtdichte</string>
+
+    <!-- Fuzzy -->
+    <string name="format_time">Zeit formatieren</string>
+    <string name="format_time_support">Beispiel: 130 Minuten als 2h 10m anzeigen</string>
+    <string name="units_sorting">Einheitenlistensortierung</string>
+    <string name="units_sorting_support">Einheitenreihenfolge ändern</string>
+
+    <!-- Units list sorting -->
+    <string name="sort_by_usage">Benutzung</string>
+    <string name="sort_by_alphabetical">Alphabetisch</string>
+
+    <!-- Fuzzy -->
+    <string name="sort_by_scale_desc">Skala (Abst.)</string>
+
+    <!-- Fuzzy -->
+    <string name="sort_by_scale_asc">Skala (Aufst.)</string>
+    <string name="color_theme_support">Farbthema auswählen</string>
+    <string name="color_scheme">Farbschema</string>
+    <string name="selected_color">Ausgewählte Farbe</string>
+    <string name="monet_mode">Stil auswählen</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/Gj9ZCNPXIfKddDQgccvboVFz.jpg 
+https://s3.eu-west-1.amazonaws.com/po-pub/i/prtM85P6x1fMuLg1I0zbkceo.png 
+
+Maybe this can be labeled better? Let me know. It should be something that can describe content of the Formatting screen. -->
+    <string name="formatting_setting_support">Genauigkeit und Zahlendarstellung</string>
+    <string name="divide_by_zero_error">Kann nicht durch 0 teilen</string>
+    <string name="date_difference">Datumsunterschied</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/uWOHJmIq9riqsq7PO82ZQp3a.png -->
+    <string name="select_time">Zeit auswählen</string>
+    <string name="date_difference_start">Anfang</string>
+    <string name="date_difference_end">Ende</string>
+    <string name="date_difference_result">Unterschied</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_years">Jahre</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_months">Monate</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_days">Tage</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_hours">Stunden</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_minutes">Minuten</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/9lSfdkfKShwyQFEF4nvbVaIb.jpg 
+
+Used in this dialog window. Should be short -->
+    <string name="next_label">Weiter</string>
 </resources>

core/base/src/main/res/values-en-rGB/strings.xml

@@ -228,11 +228,11 @@
     <string name="exabyte_per_second_short">EB/s</string>
 
     <!-- Volume -->
-    <string name="attoliter">Attoliter</string>
+    <string name="attoliter">Attolitre</string>
     <string name="attoliter_short">aL</string>
-    <string name="milliliter">Milliliter</string>
+    <string name="milliliter">Millilitre</string>
     <string name="milliliter_short">mL</string>
-    <string name="liter">Liter</string>
+    <string name="liter">Litre</string>
     <string name="liter_short">L</string>
     <string name="us_liquid_gallon">US liquid gallon</string>
     <string name="us_liquid_gallon_short">gal (US)</string>
@@ -659,10 +659,8 @@
     <string name="theme_setting">Themes</string>
     <string name="precision_setting">Precision</string>
     <string name="separator_setting">Separator</string>
-    <string name="output_format_setting">Output format</string>
+    <string name="exponential_notation_setting">Exponential notation</string>
     <string name="unit_groups_setting">Unit groups</string>
-    <string name="enable_vibrations">Vibrations</string>
-    <string name="enable_vibrations_support">Haptic feedback when clicking keyboard buttons</string>
     <string name="currency_rates_note_setting">Wrong currency rates?</string>
     <string name="currency_rates_note_title">Note</string>
     <string name="currency_rates_note_text">Currency rates are updated daily. There\'s no real-time market monitoring in the app</string>
@@ -670,30 +668,26 @@
     <string name="privacy_policy">Privacy Policy</string>
     <string name="third_party_licenses">Third party licenses</string>
     <string name="rate_this_app">Rate this app</string>
-    <string name="formatting_settings_group">Formatting</string>
+    <string name="formatting_setting">Formatting</string>
     <string name="additional_settings_group">Additional</string>
 
     <!-- Precision -->
     <string name="precision_setting_support">Number of decimal places</string>
     <string name="precision_setting_info">Converted values may have a precision higher than the preferred one.</string>
-    <string name="max_precision">1 000 (Max)</string>
+    <string name="max_precision">%1$s (Max)</string>
 
     <!-- Separator -->
     <string name="separator_setting_support">Group separator symbol</string>
-    <string name="period">Period (42.069,12)</string>
-    <string name="comma">Comma (42,069.12)</string>
-    <string name="spaces">Spaces (42 069.12)</string>
+    <string name="period">Period</string>
+    <string name="comma">Comma</string>
+    <string name="space">Space</string>
 
     <!-- Output format -->
-    <string name="output_format_setting_support">Result value formatting</string>
-    <string name="output_format_setting_info">Engineering strings look like 1E-21</string>
-    <string name="plain">Default</string>
-    <string name="allow_engineering">Allow engineering</string>
-    <string name="force_engineering">Force engineering</string>
+    <string name="exponential_notation_setting_support">Replace part of the number with E</string>
 
     <!-- Theme -->
     <string name="theme_setting_support">App look and feel</string>
-    <string name="force_auto_mode">Auto</string>
+    <string name="auto_label">Auto</string>
     <string name="force_light_mode">Light</string>
     <string name="force_dark_mode">Dark</string>
     <string name="color_theme">Colour theme</string>
@@ -787,4 +781,321 @@
     <string name="hexadecimal">Hexadecimal</string>
     <string name="hexadecimal_short">base16</string>
     <string name="number_base">Base</string>
+    <string name="enable_vibrations">Vibrations</string>
+    <string name="enable_vibrations_support">Haptic feedback when clicking keyboard buttons</string>
+    <string name="millibar">Millibar</string>
+    <string name="millibar_short">mbar</string>
+    <string name="kilopascal">Kilopascal</string>
+    <string name="kilopascal_short">kPa</string>
+    <string name="micron_of_mercury">Micron of mercury</string>
+    <string name="micron_of_mercury_short">μmHg</string>
+
+    <!-- Tools -->
+    <string name="epoch_converter">Epoch converter</string>
+
+    <!-- Calculator -->
+    <string name="calculator">Calculator</string>
+
+    <!-- Epoch -->
+    <string name="year_short">y</string>
+    <string name="month_short">m</string>
+    <string name="nautical_mile">Nautical mile</string>
+    <string name="nautical_mile_short">M</string>
+    <string name="starting_screen_setting">Starting screen</string>
+    <string name="starting_screen_setting_support">Choose which screen is shown when you launch the app</string>
+
+    <!-- Tools -->
+    <string name="unit_converter">Unit converter</string>
+    <string name="calculator_clear_history_label">Clear</string>
+    <string name="calculator_clear_history_title">Clear history</string>
+    <string name="calculator_clear_history_support">All expressions from history will be deleted forever. This action can\'t be undone!</string>
+    <string name="calculator_no_history">No history</string>
+    <string name="open_menu_description">Open menu</string>
+    <string name="microgram">Microgram</string>
+    <string name="microgram_short">µg</string>
+
+    <!-- ELECTROSTATIC CAPACITANCE -->
+    <string name="attofarad">Attofarad</string>
+    <string name="attofarad_short">aF</string>
+    <string name="statfarad">Statfarad</string>
+    <string name="statfarad_short">stF</string>
+    <string name="farad">Farad</string>
+    <string name="farad_short">F</string>
+    <string name="exafarad">Exafarad</string>
+    <string name="exafarad_short">EF</string>
+    <string name="picofarad">Picofarad</string>
+    <string name="picofarad_short">pF</string>
+    <string name="nanofarad">Nanofarad</string>
+    <string name="nanofarad_short">nF</string>
+    <string name="microfarad">Microfarad</string>
+    <string name="microfarad_short">µF</string>
+    <string name="millifarad">Millifarad</string>
+    <string name="millifarad_short">mF</string>
+    <string name="kilofarad">Kilofarad</string>
+    <string name="kilofarad_short">kF</string>
+    <string name="megafarad">Megafarad</string>
+    <string name="megafarad_short">MF</string>
+    <string name="gigafarad">Gigafarad</string>
+    <string name="gigafarad_short">GF</string>
+    <string name="petafarad">Petafarad</string>
+    <string name="petafarad_short">PF</string>
+
+    <!-- Prefixes -->
+    <string name="prefix_quetta">Quetta</string>
+    <string name="prefix_quetta_short">Q</string>
+    <string name="prefix_ronna">Ronna</string>
+    <string name="prefix_ronna_short">R</string>
+    <string name="prefix_yotta">Yotta</string>
+    <string name="prefix_yotta_short">Y</string>
+    <string name="prefix_zetta">Zetta</string>
+    <string name="prefix_zetta_short">Z</string>
+    <string name="prefix_exa">Exa</string>
+    <string name="prefix_exa_short">E</string>
+    <string name="prefix_peta">Peta</string>
+    <string name="prefix_peta_short">P</string>
+    <string name="prefix_tera">Tera</string>
+    <string name="prefix_tera_short">T</string>
+    <string name="prefix_giga">Giga</string>
+    <string name="prefix_giga_short">G</string>
+    <string name="prefix_mega">Mega</string>
+    <string name="prefix_mega_short">M</string>
+    <string name="prefix_kilo">Kilo</string>
+    <string name="prefix_kilo_short">k</string>
+    <string name="prefix_hecto">Hecto</string>
+    <string name="prefix_hecto_short">h</string>
+    <string name="prefix_deca">Deca</string>
+    <string name="prefix_deca_short">da</string>
+    <string name="prefix_base">Base</string>
+    <string name="prefix_base_short">Base</string>
+    <string name="prefix_deci">Deci</string>
+    <string name="prefix_deci_short">d</string>
+    <string name="prefix_centi">Centi</string>
+    <string name="prefix_centi_short">c</string>
+    <string name="prefix_milli">Milli</string>
+    <string name="prefix_milli_short">m</string>
+    <string name="prefix_micro">Micro</string>
+    <string name="prefix_micro_short">μ</string>
+    <string name="prefix_nano">Nano</string>
+    <string name="prefix_nano_short">n</string>
+    <string name="prefix_pico">Pico</string>
+    <string name="prefix_pico_short">p</string>
+    <string name="prefix_femto">Femto</string>
+    <string name="prefix_femto_short">f</string>
+    <string name="prefix_atto">Atto</string>
+    <string name="prefix_atto_short">a</string>
+    <string name="prefix_zepto">Zepto</string>
+    <string name="prefix_zepto_short">z</string>
+    <string name="prefix_yocto">Yocto</string>
+    <string name="prefix_yocto_short">y</string>
+    <string name="prefix_ronto">Ronto</string>
+    <string name="prefix_ronto_short">r</string>
+    <string name="prefix_quecto">Quecto</string>
+    <string name="prefix_quecto_short">q</string>
+
+    <!-- Force -->
+    <string name="newton">Newton</string>
+    <string name="newton_short">N</string>
+    <string name="kilonewton">Kilonewton</string>
+    <string name="kilonewton_short">kN</string>
+    <string name="gram_force">Gram-force</string>
+    <string name="gram_force_short">gf</string>
+    <string name="kilogram_force">Kilogram-force</string>
+    <string name="kilogram_force_short">kgf</string>
+    <string name="ton_force">Ton-force</string>
+    <string name="ton_force_short">tf</string>
+    <string name="millinewton">Millinewton</string>
+    <string name="millinewton_short">mN</string>
+    <string name="attonewton">Attonewton</string>
+    <string name="attonewton_short">aN</string>
+    <string name="dyne">Dyne</string>
+    <string name="dyne_short">dyn</string>
+    <string name="joule_per_meter">Joule/metre</string>
+    <string name="joule_per_meter_short">J/m</string>
+    <string name="joule_per_centimeter">Joule/centimetre</string>
+    <string name="joule_per_centimeter_short">J/cm</string>
+    <string name="kilopound_force">Kilopound-force</string>
+    <string name="kilopound_force_short">kipf</string>
+    <string name="pound_force">Pound-force</string>
+    <string name="pound_force_short">lbf</string>
+    <string name="ounce_force">Ounce-force</string>
+    <string name="ounce_force_short">ozf</string>
+    <string name="pond">Pond</string>
+    <string name="pond_short">p</string>
+    <string name="kilopond">Kilopond</string>
+    <string name="kilopond_short">kp</string>
+
+    <!-- Torque -->
+    <string name="newton_meter">Newton metre</string>
+    <string name="newton_meter_short">N*m</string>
+    <string name="newton_centimeter">Newton centimetre</string>
+    <string name="newton_centimeter_short">N*cm</string>
+    <string name="newton_millimeter">Newton millimetre</string>
+    <string name="newton_millimeter_short">N*mm</string>
+    <string name="kilonewton_meter">Kilonewton metre</string>
+    <string name="kilonewton_meter_short">kN*m</string>
+    <string name="dyne_meter">Dyne metre</string>
+    <string name="dyne_meter_short">dyn*m</string>
+    <string name="dyne_centimeter">Dyne centimetre</string>
+    <string name="dyne_centimeter_short">dyn*cm</string>
+    <string name="dyne_millimeter">Dyne millimetre</string>
+    <string name="dyne_millimeter_short">dyn*mm</string>
+    <string name="kilogram_force_meter">Kilogram-force metre</string>
+    <string name="kilogram_force_meter_short">kgf*m</string>
+    <string name="kilogram_force_centimeter">Kilogram-force centimetre</string>
+    <string name="kilogram_force_centimeter_short">kgf*cm</string>
+    <string name="kilogram_force_millimeter">Kilogram-force millimetre</string>
+    <string name="kilogram_force_millimeter_short">kgf*mm</string>
+    <string name="gram_force_meter">Gram-force metre</string>
+    <string name="gram_force_meter_short">gf*m</string>
+    <string name="gram_force_centimeter">Gram-force centimetre</string>
+    <string name="gram_force_centimeter_short">gf*cm</string>
+    <string name="gram_force_millimeter">Gram-force millimetre</string>
+    <string name="gram_force_millimeter_short">gf*mm</string>
+    <string name="ounce_force_foot">Ounce-force foot</string>
+    <string name="ounce_force_foot_short">ozf*ft</string>
+    <string name="ounce_force_inch">Ounce-force inch</string>
+    <string name="ounce_force_inch_short">ozf*in</string>
+    <string name="pound_force_foot">Pound-force foot</string>
+    <string name="pound_force_foot_short">lbf*ft</string>
+    <string name="pound_force_inch">Pound-force inch</string>
+    <string name="pound_force_inch_short">lbf*in</string>
+
+    <!-- Flow rate -->
+    <string name="liter_per_hour">Litre/hour</string>
+    <string name="liter_per_hour_short">L/h</string>
+    <string name="liter_per_minute">Litre/minute</string>
+    <string name="liter_per_minute_short">L/m</string>
+    <string name="liter_per_second">Litre/second</string>
+    <string name="liter_per_second_short">L/s</string>
+    <string name="milliliter_per_hour">Millilitre/hour</string>
+    <string name="milliliter_per_hour_short">mL/h</string>
+    <string name="milliliter_per_minute">Millilitre/minute</string>
+    <string name="milliliter_per_minute_short">mL/m</string>
+    <string name="milliliter_per_second">Millilitre/second</string>
+    <string name="milliliter_per_second_short">mL/s</string>
+    <string name="cubic_meter_per_hour">Cubic Metre/hour</string>
+    <string name="cubic_meter_per_hour_short">m3/h</string>
+    <string name="cubic_meter_per_minute">Cubic Metre/minute</string>
+    <string name="cubic_meter_per_minute_short">m3/m</string>
+    <string name="cubic_meter_per_second">Cubic Metre/second</string>
+    <string name="cubic_meter_per_second_short">m3/s</string>
+    <string name="cubic_millimeter_per_hour">Cubic Millimetre/hour</string>
+    <string name="cubic_millimeter_per_hour_short">mm3/h</string>
+    <string name="cubic_millimeter_per_minute">Cubic Millimetre/minute</string>
+    <string name="cubic_millimeter_per_minute_short">mm3/m</string>
+    <string name="cubic_millimeter_per_second">Cubic Millimetre/second</string>
+    <string name="cubic_millimeter_per_second_short">mm3/s</string>
+    <string name="cubic_foot_per_hour">Cubic Foot/hour</string>
+    <string name="cubic_foot_per_hour_short">ft3/h</string>
+    <string name="cubic_foot_per_minute">Cubic Foot/minute</string>
+    <string name="cubic_foot_per_minute_short">ft3/m</string>
+    <string name="cubic_foot_per_second">Cubic Foot/second</string>
+    <string name="cubic_foot_per_second_short">ft3/s</string>
+    <string name="gallon_per_hour_us">Gallon/hour (U.S.)</string>
+    <string name="gallon_per_hour_us_short">gal/h</string>
+    <string name="gallon_per_minute_us">Gallon/minute (U.S.)</string>
+    <string name="gallon_per_minute_us_short">gal/m</string>
+    <string name="gallon_per_second_us">Gallon/second (U.S.)</string>
+    <string name="gallon_per_second_us_short">gal/s</string>
+    <string name="gallon_per_hour_imperial">Gallon/hour (Imperial)</string>
+    <string name="gallon_per_hour_imperial_short">gal/h</string>
+    <string name="gallon_per_minute_imperial">Gallon/minute (Imperial)</string>
+    <string name="gallon_per_minute_imperial_short">gal/m</string>
+    <string name="gallon_per_second_imperial">Gallon/second (Imperial)</string>
+    <string name="gallon_per_second_imperial_short">gal/s</string>
+
+    <!-- Luminance -->
+    <string name="candela_per_square_meter">Candela/square metre</string>
+    <string name="candela_per_square_meter_short">cd/m^2</string>
+    <string name="candela_per_square_centimeter">Candela/square centimetre</string>
+    <string name="candela_per_square_centimeter_short">cd/cm^2</string>
+    <string name="candela_per_square_foot">Candela/square foot</string>
+    <string name="candela_per_square_foot_short">cd/ft^2</string>
+    <string name="candela_per_square_inch">Candela/square inch</string>
+    <string name="candela_per_square_inch_short">cd/in^2</string>
+    <string name="kilocandela_per_square_meter">Kilocandela/square metre</string>
+    <string name="kilocandela_per_square_meter_short">kcd</string>
+    <string name="stilb">Stilb</string>
+    <string name="stilb_short">sb</string>
+    <string name="lumen_per_square_meter_per_steradian">Lumen/square metre/steradian</string>
+    <string name="lumen_per_square_meter_per_steradian_short">lm/m^2/sr</string>
+    <string name="lumen_per_square_centimeter_per_steradian">Lumen/square centimetre/steradian</string>
+    <string name="lumen_per_square_centimeter_per_steradian_short">lm/cm^2/sr</string>
+    <string name="lumen_per_square_foot_per_steradian">Lumen/square foot/steradian</string>
+    <string name="lumen_per_square_foot_per_steradian_short">lm/ft^2/sr</string>
+    <string name="watt_per_square_centimeter_per_steradian">Watt/square centimetre/steradian</string>
+    <string name="watt_per_square_centimeter_per_steradian_short">W/cm^2/sr</string>
+    <string name="nit">Nit</string>
+    <string name="nit_short">nt</string>
+    <string name="millinit">Millinit</string>
+    <string name="millinit_short">mnt</string>
+    <string name="lambert">Lambert</string>
+    <string name="lambert_short">L</string>
+    <string name="millilambert">Millilambert</string>
+    <string name="millilambert_short">mL</string>
+    <string name="foot_lambert">Foot-lambert</string>
+    <string name="foot_lambert_short">fL</string>
+    <string name="apostilb">Apostilb</string>
+    <string name="apostilb_short">asb</string>
+    <string name="blondel">Blondel</string>
+    <string name="blondel_short">blondel</string>
+    <string name="bril">Bril</string>
+    <string name="bril_short">bril</string>
+    <string name="skot">Skot</string>
+    <string name="skot_short">sk</string>
+    <string name="electrostatic_capacitance">Capacitance</string>
+    <string name="prefix">Prefix</string>
+    <string name="force">Force</string>
+    <string name="torque">Torque</string>
+    <string name="flow_rate">Flow</string>
+    <string name="luminance">Luminance</string>
+    <string name="format_time">Format time</string>
+    <string name="format_time_support">Example: Show 130 minutes as 2h 10m</string>
+    <string name="units_sorting">Units list sorting</string>
+    <string name="units_sorting_support">Change units order</string>
+
+    <!-- Units list sorting -->
+    <string name="sort_by_usage">Usage</string>
+    <string name="sort_by_alphabetical">Alphabetical</string>
+    <string name="sort_by_scale_desc">Scale (Desc.)</string>
+    <string name="sort_by_scale_asc">Scale (Asc.)</string>
+    <string name="color_theme_support">Pick a theming mode</string>
+    <string name="color_scheme">Colour scheme</string>
+    <string name="selected_color">Selected colour</string>
+    <string name="monet_mode">Selected style</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/Gj9ZCNPXIfKddDQgccvboVFz.jpg 
+https://s3.eu-west-1.amazonaws.com/po-pub/i/prtM85P6x1fMuLg1I0zbkceo.png 
+
+Maybe this can be labeled better? Let me know. It should be something that can describe content of the Formatting screen. -->
+    <string name="formatting_setting_support">Precision and numbers appearance</string>
+    <string name="divide_by_zero_error">Can\'t divide by 0</string>
+    <string name="date_difference">Date difference</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/uWOHJmIq9riqsq7PO82ZQp3a.png -->
+    <string name="select_time">Select time</string>
+    <string name="date_difference_start">Start</string>
+    <string name="date_difference_end">End</string>
+    <string name="date_difference_result">Difference</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_years">Years</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_months">Months</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_days">Days</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_hours">Hours</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_minutes">Minutes</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/9lSfdkfKShwyQFEF4nvbVaIb.jpg 
+
+Used in this dialog window. Should be short -->
+    <string name="next_label">Next</string>
+    <string name="formatting_setting_preview_box_label">Preview (click to switch)</string>
 </resources>

core/base/src/main/res/values-fr/strings.xml

@@ -659,7 +659,9 @@
     <string name="theme_setting">Thèmes</string>
     <string name="precision_setting">Précision</string>
     <string name="separator_setting">Séparateur</string>
-    <string name="output_format_setting">Format de sortie</string>
+
+    <!-- Fuzzy -->
+    <string name="exponential_notation_setting">Notation exponentielle</string>
     <string name="unit_groups_setting">Groupes d\'unités</string>
     <string name="currency_rates_note_title">Note</string>
     <string name="currency_rates_note_text">Les taux de change sont mis à jour quotidiennement. L\'application ne permet pas de suivre le marché en temps réel.</string>
@@ -667,21 +669,22 @@
     <string name="privacy_policy">Politique de confidentialité</string>
     <string name="third_party_licenses">Licences tierces</string>
     <string name="rate_this_app">Évaluer l\'application</string>
-    <string name="formatting_settings_group">Formattage</string>
+    <string name="formatting_setting">Formattage</string>
     <string name="additional_settings_group">Additional</string>
 
     <!-- Precision -->
     <string name="precision_setting_support">Nombre de décimales</string>
     <string name="precision_setting_info">Les valeurs converties peuvent avoir une précision supérieure à la précision préférée.</string>
-    <string name="max_precision">1 000 (Max)</string>
+    <string name="max_precision">%1$s (Max)</string>
 
     <!-- Separator -->
     <string name="separator_setting_support">Symbole de séparation de groupe</string>
-    <string name="period">Période (42.069,12)</string>
-    <string name="comma">Virgule (42,069.12)</string>
-    <string name="spaces">Espaces (42 069.12)</string>
-    <string name="plain">Défaut</string>
-    <string name="force_auto_mode">Auto</string>
+    <string name="period">Période</string>
+    <string name="comma">Virgule</string>
+
+    <!-- Fuzzy -->
+    <string name="space">Espaces</string>
+    <string name="auto_label">Auto</string>
     <string name="force_light_mode">Clair</string>
     <string name="force_dark_mode">Sombre</string>
     <string name="force_amoled_mode">AMOLED Noir</string>

core/base/src/main/res/values-ru/strings.xml

@@ -659,7 +659,7 @@
     <string name="theme_setting">Темы</string>
     <string name="precision_setting">Точность</string>
     <string name="separator_setting">Разделитель</string>
-    <string name="output_format_setting">Формат вывода</string>
+    <string name="exponential_notation_setting">Экспоненциальная нотация</string>
     <string name="unit_groups_setting">Группы величин</string>
     <string name="currency_rates_note_setting">Неправильные курсы валют?</string>
     <string name="currency_rates_note_title">Внимание</string>
@@ -668,35 +668,31 @@
     <string name="privacy_policy">Политика конфиденциальности</string>
     <string name="third_party_licenses">Лицензии третьих лиц</string>
     <string name="rate_this_app">Оценить приложение</string>
-    <string name="formatting_settings_group">Форматирование</string>
+    <string name="formatting_setting">Форматирование</string>
     <string name="additional_settings_group">Дополнительное</string>
 
     <!-- Precision -->
     <string name="precision_setting_support">Количество десятичных знаков</string>
     <string name="precision_setting_info">Переводимые значения могут иметь точность выше предпочтительной.</string>
-    <string name="max_precision">1 000 (Максимум)</string>
+    <string name="max_precision">%1$s (Максимум)</string>
 
     <!-- Separator -->
     <string name="separator_setting_support">Символ разделителя</string>
-    <string name="period">Точка (42.069,12)</string>
-    <string name="comma">Запятая (42,069.12)</string>
-    <string name="spaces">Пробел (42 069.12)</string>
+    <string name="period">Точка</string>
+    <string name="comma">Запятая</string>
+    <string name="space">Пробел</string>
 
     <!-- Output format -->
-    <string name="output_format_setting_support">Формат результата перевода</string>
-    <string name="output_format_setting_info">Инженерный формат выглядит как 1E-21</string>
-    <string name="plain">По умолчанию</string>
-    <string name="allow_engineering">Разрешить инженерный</string>
-    <string name="force_engineering">Преимущественно инженерный</string>
+    <string name="exponential_notation_setting_support">Замените часть числа на E</string>
 
     <!-- Theme -->
     <string name="theme_setting_support">Внешний вид приложения</string>
-    <string name="force_auto_mode">Автоматическая</string>
+    <string name="auto_label">Авто</string>
     <string name="force_light_mode">Светлая</string>
-    <string name="force_dark_mode">Темная</string>
+    <string name="force_dark_mode">Тёмная</string>
     <string name="color_theme">Цветовая тема</string>
-    <string name="force_amoled_mode">Темная AMOLED</string>
-    <string name="force_amoled_mode_support">Использовать черный фон в темных темах</string>
+    <string name="force_amoled_mode">Чёрная AMOLED</string>
+    <string name="force_amoled_mode_support">Использовать чёрный фон в тёмной теме</string>
     <string name="enable_dynamic_colors">Динамичные цвета</string>
     <string name="enable_dynamic_colors_support">Использовать цвета обоев</string>
 
@@ -1048,7 +1044,7 @@
     <string name="skot">Скот</string>
     <string name="skot_short">ск</string>
     <string name="electrostatic_capacitance">Емкость</string>
-    <string name="prefix">Префиск</string>
+    <string name="prefix">Префикс</string>
     <string name="force">Сила</string>
     <string name="torque">Момент</string>
     <string name="flow_rate">Течение</string>
@@ -1067,4 +1063,39 @@
     <string name="color_scheme">Цветовая схема</string>
     <string name="selected_color">Выбранный цвет</string>
     <string name="monet_mode">Выбранный стиль</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/Gj9ZCNPXIfKddDQgccvboVFz.jpg 
+https://s3.eu-west-1.amazonaws.com/po-pub/i/prtM85P6x1fMuLg1I0zbkceo.png 
+
+Maybe this can be labeled better? Let me know. It should be something that can describe content of the Formatting screen. -->
+    <string name="formatting_setting_support">Точность и представление чисел</string>
+    <string name="divide_by_zero_error">Нельзя делить на 0</string>
+    <string name="date_difference">Разница между датами</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/uWOHJmIq9riqsq7PO82ZQp3a.png -->
+    <string name="select_time">Выберите время</string>
+    <string name="date_difference_start">Начало</string>
+    <string name="date_difference_end">Конец</string>
+    <string name="date_difference_result">Разница</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_years">Лет</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_months">Месяцев</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_days">Дней</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_hours">Часов</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/33QTn2NVrjJT772cBDFRqSMH.png -->
+    <string name="date_difference_minutes">Минут</string>
+
+    <!-- https://s3.eu-west-1.amazonaws.com/po-pub/i/9lSfdkfKShwyQFEF4nvbVaIb.jpg 
+
+Used in this dialog window. Should be short -->
+    <string name="next_label">Далее</string>
+    <string name="formatting_setting_preview_box_label">Предпросмотр (нажмите для переключения)</string>
 </resources>

core/ui/build.gradle.kts

@@ -16,6 +16,8 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+@file:Suppress("UnstableApiUsage")
+
 plugins {
     id("unitto.library")
     id("unitto.library.compose")
@@ -35,7 +37,6 @@ android {
 
 dependencies {
     testImplementation(libs.junit)
-    testImplementation(libs.org.robolectric)
     testImplementation(libs.androidx.compose.ui.test.junit4)
     debugImplementation(libs.androidx.compose.ui.test.manifest)
 

core/ui/src/main/java/com/sadellie/unitto/core/ui/Formatter.kt

@@ -1,251 +0,0 @@
-/*
- * Unitto is a unit converter for Android
- * Copyright (c) 2022-2023 Elshan Agaev
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-
-package com.sadellie.unitto.core.ui
-
-import android.content.Context
-import com.sadellie.unitto.core.base.Separator
-import com.sadellie.unitto.core.base.Token
-import java.math.BigDecimal
-import java.math.RoundingMode
-
-// Legacy, LOL. Will change later
-object Formatter : UnittoFormatter()
-
-open class UnittoFormatter {
-    /**
-     * This regex will catch things like "123.456", "123", ".456"
-     */
-    private val numbersRegex = Regex("[\\d.]+")
-
-    private val SPACE = " "
-    private val PERIOD = "."
-    private val COMMA = ","
-
-    /**
-     * Grouping separator.
-     */
-    var grouping: String = SPACE
-
-    /**
-     * Fractional part separator.
-     */
-    var fractional = Token.comma
-
-    private val timeDivisions by lazy {
-        mapOf(
-            R.string.day_short to BigDecimal("86400000000000000000000"),
-            R.string.hour_short to BigDecimal("3600000000000000000000"),
-            R.string.minute_short to BigDecimal("60000000000000000000"),
-            R.string.second_short to BigDecimal("1000000000000000000"),
-            R.string.millisecond_short to BigDecimal("1000000000000000"),
-            R.string.microsecond_short to BigDecimal("1000000000000"),
-            R.string.nanosecond_short to BigDecimal("1000000000"),
-            R.string.attosecond_short to BigDecimal("1"),
-        )
-    }
-
-    /**
-     * Change current separator to another [separator].
-     *
-     * @see [Separator]
-     */
-    fun setSeparator(separator: Int) {
-        grouping = when (separator) {
-            Separator.PERIOD -> PERIOD
-            Separator.COMMA -> COMMA
-            else -> SPACE
-        }
-        fractional = if (separator == Separator.PERIOD) Token.comma else Token.dot
-    }
-
-    /**
-     * Format [input].
-     *
-     * This will replace operators to their more appealing variants: divide, multiply and minus.
-     * Plus operator remains unchanged.
-     *
-     * Numbers will also be formatted.
-     *
-     * @see [formatNumber]
-     */
-    fun format(input: String): String {
-        // Don't do anything to engineering string.
-        if (input.contains(Token.E)) return input.replace(Token.dot, fractional)
-
-        var output = input
-        val allNumbers: List<String> = input.getOnlyNumbers()
-
-        allNumbers.forEach {
-            output = output.replace(it, formatNumber(it))
-        }
-
-        Token.internalToDisplay.forEach {
-            output = output.replace(it.key, it.value)
-        }
-
-        return output
-    }
-
-    /**
-     * Reapply formatting. Reverses [format] and applies [format] again.
-     */
-    fun reFormat(input: String): String {
-        // We get  123.45,6789
-        // We need 12.345,6789
-
-        // 123.45,6789
-        // Remove grouping
-        // 12345,6789
-        // Replace fractional with "." because formatter accepts only numbers where fractional is a dot
-        return format(
-            input
-                .replace(grouping, "")
-                .replace(fractional, Token.dot)
-        )
-    }
-
-    /**
-     * Helper method to change formatting from [input] with a specified [separator] to the one that
-     * is set for this [UnittoFormatter].
-     */
-    fun fromSeparator(input: String, separator: Int): String {
-        val sGrouping = when (separator) {
-            Separator.PERIOD -> PERIOD
-            Separator.COMMA -> COMMA
-            else -> SPACE
-        }
-            .also { if (it == grouping) return input }
-        val sFractional = if (separator == Separator.PERIOD) Token.comma else Token.dot
-
-        return input
-            .replace(sGrouping, "\t")
-            .replace(sFractional, fractional)
-            .replace("\t", grouping)
-    }
-
-    fun toSeparator(input: String, separator: Int): String {
-        val output = filterUnknownSymbols(input).replace(fractional, Token.dot)
-        val sGrouping = when (separator) {
-            Separator.PERIOD -> PERIOD
-            Separator.COMMA -> COMMA
-            else -> SPACE
-        }
-        val sFractional = if (separator == Separator.PERIOD) Token.comma else Token.dot
-
-        return format(output)
-            .replace(grouping, "\t")
-            .replace(fractional, sFractional)
-            .replace("\t", sGrouping)
-    }
-
-    fun removeGrouping(input: String): String = input.replace(grouping, "")
-
-    /**
-     * Takes [input] and [basicUnit] of the  unit to format it to be more human readable.
-     *
-     * @return String like "1d 12h 12s".
-     */
-    fun formatTime(context: Context, input: String, basicUnit: BigDecimal?): String {
-        if (basicUnit == null) return Token._0
-
-        try {
-            // Don't need magic if the input is zero
-            if (BigDecimal(input).compareTo(BigDecimal.ZERO) == 0) return Token._0
-        } catch (e: NumberFormatException) {
-            // For case such as "10-" and "("
-            return Token._0
-        }
-        // Attoseconds don't need "magic"
-        if (basicUnit.compareTo(BigDecimal.ONE) == 0) return formatNumber(input)
-
-        var result = if (input.startsWith(Token.minus)) Token.minus else ""
-        var remainingSeconds = BigDecimal(input)
-            .abs()
-            .multiply(basicUnit)
-            .setScale(0, RoundingMode.HALF_EVEN)
-
-        if (remainingSeconds.compareTo(BigDecimal.ZERO) == 0) return Token._0
-
-        timeDivisions.forEach { (timeStr, divider) ->
-            val division = remainingSeconds.divideAndRemainder(divider)
-            val time = division.component1()
-            remainingSeconds = division.component2()
-            if (time.compareTo(BigDecimal.ZERO) == 1) {
-                result += "${formatNumber(time.toPlainString())}${context.getString(timeStr)} "
-            }
-        }
-        return result.trimEnd()
-    }
-
-    /**
-     * Format given [input].
-     *
-     * Input must be a number with dot!!!. Will replace grouping separators and fractional part (dot)
-     * separators.
-     *
-     * @see grouping
-     * @see fractional
-     */
-    private fun formatNumber(input: String): String {
-        if (input.any { it.isLetter() }) return input
-
-        var firstPart = input.takeWhile { it != '.' }
-        val remainingPart = input.removePrefix(firstPart)
-
-        // Number of empty symbols (spaces) we need to add to correctly split into chunks.
-        val offset = 3 - firstPart.length.mod(3)
-        val output = if (offset != 3) {
-            // We add some spaces at the beginning so that last chunk has 3 symbols
-            firstPart = " ".repeat(offset) + firstPart
-            firstPart.chunked(3).joinToString(grouping).drop(offset)
-        } else {
-            firstPart.chunked(3).joinToString(grouping)
-        }
-
-        return (output + remainingPart.replace(".", fractional))
-    }
-
-    /**
-     * @receiver Must be a string with a dot (".") used as a fractional.
-     */
-    private fun String.getOnlyNumbers(): List<String> =
-        numbersRegex.findAll(this).map(MatchResult::value).toList()
-
-    fun filterUnknownSymbols(input: String): String {
-        var clearStr = input.replace(" ", "")
-        var garbage = clearStr
-
-        // String with unknown symbols
-        Token.knownSymbols.plus(fractional).forEach {
-            garbage = garbage.replace(it, " ")
-        }
-
-        // Remove unknown symbols from input
-        garbage.split(" ").forEach {
-            clearStr = clearStr.replace(it, "")
-        }
-
-        clearStr = clearStr
-            .replace(Token.divide, Token.divideDisplay)
-            .replace(Token.multiply, Token.multiplyDisplay)
-            .replace(Token.minus, Token.minusDisplay)
-
-        return clearStr
-    }
-}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/DateTimePickerDialog.kt

@@ -0,0 +1,284 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import android.text.format.DateFormat
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.requiredWidth
+import androidx.compose.foundation.layout.wrapContentHeight
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.DatePicker
+import androidx.compose.material3.DatePickerDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.material3.TimePicker
+import androidx.compose.material3.TimePickerLayoutType
+import androidx.compose.material3.rememberDatePickerState
+import androidx.compose.material3.rememberTimePickerState
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.layout.Layout
+import androidx.compose.ui.layout.Placeable
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.window.DialogProperties
+import com.sadellie.unitto.core.base.R
+import java.time.Instant
+import java.time.LocalDateTime
+import java.time.ZoneId
+import java.time.ZoneOffset
+import kotlin.math.max
+
+@Composable
+fun TimePickerDialog(
+    modifier: Modifier = Modifier,
+    localDateTime: LocalDateTime,
+    confirmLabel: String = stringResource(R.string.ok_label),
+    dismissLabel: String = stringResource(R.string.cancel_label),
+    onDismiss: () -> Unit = {},
+    onConfirm: (LocalDateTime) -> Unit,
+    vertical: Boolean
+) {
+    val pickerState = rememberTimePickerState(
+        localDateTime.hour,
+        localDateTime.minute,
+        DateFormat.is24HourFormat(LocalContext.current)
+    )
+
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        modifier = modifier.wrapContentHeight(),
+        properties = DialogProperties(usePlatformDefaultWidth = vertical)
+    ) {
+        Surface(
+            modifier = modifier,
+            shape = MaterialTheme.shapes.extraLarge,
+            color = MaterialTheme.colorScheme.surface,
+            tonalElevation = 6.dp,
+        ) {
+            Column(
+                modifier = Modifier.padding(24.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.SpaceBetween,
+            ) {
+                Text(
+                    text = stringResource(R.string.select_time),
+                    style = MaterialTheme.typography.labelMedium,
+                    modifier = Modifier.align(Alignment.Start)
+                )
+
+                TimePicker(
+                    state = pickerState,
+                    modifier = Modifier.padding(top = 20.dp),
+                    layoutType = if (vertical) TimePickerLayoutType.Vertical else TimePickerLayoutType.Horizontal
+                )
+
+                Row(
+                    modifier = Modifier.align(Alignment.End),
+                    horizontalArrangement = Arrangement.spacedBy(8.dp)
+                ) {
+                    TextButton(
+                        onClick = onDismiss
+                    ) {
+                        Text(text = dismissLabel)
+                    }
+                    TextButton(
+                        onClick = {
+                            onConfirm(
+                                localDateTime
+                                    .withHour(pickerState.hour)
+                                    .withMinute(pickerState.minute)
+                            )
+                        }
+                    ) {
+                        Text(text = confirmLabel)
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+fun DatePickerDialog(
+    modifier: Modifier = Modifier,
+    localDateTime: LocalDateTime,
+    confirmLabel: String = stringResource(R.string.ok_label),
+    dismissLabel: String = stringResource(R.string.cancel_label),
+    onDismiss: () -> Unit = {},
+    onConfirm: (LocalDateTime) -> Unit,
+) {
+    val pickerState = rememberDatePickerState(localDateTime.toEpochSecond(ZoneOffset.UTC) * 1000)
+
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        modifier = modifier.wrapContentHeight(),
+        properties = DialogProperties(usePlatformDefaultWidth = false)
+    ) {
+        Surface(
+            modifier = modifier
+                .requiredWidth(360.dp)
+                .heightIn(max = 568.dp),
+            shape = DatePickerDefaults.shape,
+            color = MaterialTheme.colorScheme.surface,
+            tonalElevation = 6.dp,
+        ) {
+            Column(verticalArrangement = Arrangement.SpaceBetween) {
+                DatePicker(state = pickerState)
+
+                Box(modifier = Modifier
+                    .align(Alignment.End)
+                    .padding(DialogButtonsPadding)) {
+
+                    AlertDialogFlowRow(
+                        mainAxisSpacing = DialogButtonsMainAxisSpacing,
+                        crossAxisSpacing = DialogButtonsCrossAxisSpacing
+                    ) {
+                        TextButton(
+                            onClick = onDismiss
+                        ) {
+                            Text(text = dismissLabel)
+                        }
+                        TextButton(
+                            onClick = {
+                                val millis = pickerState.selectedDateMillis ?: return@TextButton
+
+                                val date = LocalDateTime.ofInstant(
+                                    Instant.ofEpochMilli(millis), ZoneId.systemDefault()
+                                )
+
+                                onConfirm(
+                                    localDateTime
+                                        .withYear(date.year)
+                                        .withMonth(date.monthValue)
+                                        .withDayOfMonth(date.dayOfMonth)
+                                )
+                            }
+                        ) {
+                            Text(text = confirmLabel)
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+// From androidx/compose/material3/AlertDialog.kt
+@Composable
+private fun AlertDialogFlowRow(
+    mainAxisSpacing: Dp,
+    crossAxisSpacing: Dp,
+    content: @Composable () -> Unit
+) {
+    Layout(content) { measurables, constraints ->
+        val sequences = mutableListOf<List<Placeable>>()
+        val crossAxisSizes = mutableListOf<Int>()
+        val crossAxisPositions = mutableListOf<Int>()
+
+        var mainAxisSpace = 0
+        var crossAxisSpace = 0
+
+        val currentSequence = mutableListOf<Placeable>()
+        var currentMainAxisSize = 0
+        var currentCrossAxisSize = 0
+
+        // Return whether the placeable can be added to the current sequence.
+        fun canAddToCurrentSequence(placeable: Placeable) =
+            currentSequence.isEmpty() || currentMainAxisSize + mainAxisSpacing.roundToPx() +
+                    placeable.width <= constraints.maxWidth
+
+        // Store current sequence information and start a new sequence.
+        fun startNewSequence() {
+            if (sequences.isNotEmpty()) {
+                crossAxisSpace += crossAxisSpacing.roundToPx()
+            }
+            sequences += currentSequence.toList()
+            crossAxisSizes += currentCrossAxisSize
+            crossAxisPositions += crossAxisSpace
+
+            crossAxisSpace += currentCrossAxisSize
+            mainAxisSpace = max(mainAxisSpace, currentMainAxisSize)
+
+            currentSequence.clear()
+            currentMainAxisSize = 0
+            currentCrossAxisSize = 0
+        }
+
+        for (measurable in measurables) {
+            // Ask the child for its preferred size.
+            val placeable = measurable.measure(constraints)
+
+            // Start a new sequence if there is not enough space.
+            if (!canAddToCurrentSequence(placeable)) startNewSequence()
+
+            // Add the child to the current sequence.
+            if (currentSequence.isNotEmpty()) {
+                currentMainAxisSize += mainAxisSpacing.roundToPx()
+            }
+            currentSequence.add(placeable)
+            currentMainAxisSize += placeable.width
+            currentCrossAxisSize = max(currentCrossAxisSize, placeable.height)
+        }
+
+        if (currentSequence.isNotEmpty()) startNewSequence()
+
+        val mainAxisLayoutSize = max(mainAxisSpace, constraints.minWidth)
+
+        val crossAxisLayoutSize = max(crossAxisSpace, constraints.minHeight)
+
+        layout(mainAxisLayoutSize, crossAxisLayoutSize) {
+            sequences.forEachIndexed { i, placeables ->
+                val childrenMainAxisSizes = IntArray(placeables.size) { j ->
+                    placeables[j].width +
+                            if (j < placeables.lastIndex) mainAxisSpacing.roundToPx() else 0
+                }
+                val arrangement = Arrangement.End
+                val mainAxisPositions = IntArray(childrenMainAxisSizes.size) { 0 }
+                with(arrangement) {
+                    arrange(
+                        mainAxisLayoutSize, childrenMainAxisSizes,
+                        layoutDirection, mainAxisPositions
+                    )
+                }
+                placeables.forEachIndexed { j, placeable ->
+                    placeable.place(
+                        x = mainAxisPositions[j],
+                        y = crossAxisPositions[i]
+                    )
+                }
+            }
+        }
+    }
+}
+
+private val DialogButtonsPadding by lazy { PaddingValues(bottom = 8.dp, end = 6.dp) }
+private val DialogButtonsMainAxisSpacing by lazy { 8.dp }
+private val DialogButtonsCrossAxisSpacing by lazy { 12.dp }

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/KeyboardButton.kt

@@ -20,25 +20,18 @@ package com.sadellie.unitto.core.ui.common
 
 import android.content.res.Configuration
 import android.view.HapticFeedbackConstants
-import androidx.compose.animation.core.FastOutSlowInEasing
-import androidx.compose.animation.core.animateIntAsState
-import androidx.compose.animation.core.tween
-import androidx.compose.foundation.interaction.MutableInteractionSource
-import androidx.compose.foundation.interaction.collectIsPressedAsState
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxHeight
-import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.platform.LocalConfiguration
 import androidx.compose.ui.platform.LocalView
+import kotlinx.coroutines.launch
 
 @Composable
 fun BasicKeyboardButton(
@@ -52,21 +45,21 @@ fun BasicKeyboardButton(
     contentHeight: Float
 ) {
     val view = LocalView.current
-    val interactionSource = remember { MutableInteractionSource() }
-    val isPressed by interactionSource.collectIsPressedAsState()
-    val cornerRadius: Int by animateIntAsState(
-        targetValue = if (isPressed) 30 else 50,
-        animationSpec = tween(easing = FastOutSlowInEasing),
-    )
+    val coroutineScope = rememberCoroutineScope()
 
     UnittoButton(
         modifier = modifier,
-        onClick = onClick,
+        onClick = {
+            onClick()
+            if (allowVibration) {
+                coroutineScope.launch {
+                    view.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP)
+                }
+            }
+                  },
         onLongClick = onLongClick,
-        shape = RoundedCornerShape(cornerRadius),
         containerColor = containerColor,
-        contentPadding = PaddingValues(),
-        interactionSource = interactionSource
+        contentPadding = PaddingValues()
     ) {
         Icon(
             imageVector = icon,
@@ -75,10 +68,6 @@ fun BasicKeyboardButton(
             tint = iconColor
         )
     }
-
-    LaunchedEffect(key1 = isPressed) {
-        if (isPressed and allowVibration) view.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP)
-    }
 }
 
 @Composable

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/MenuButton.kt

@@ -24,7 +24,7 @@ import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.stringResource
-import com.sadellie.unitto.core.ui.R
+import com.sadellie.unitto.core.base.R
 
 /**
  * Button that is used in Top bars

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/ModifierExtensions.kt

@@ -0,0 +1,87 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import androidx.compose.animation.core.FastOutSlowInEasing
+import androidx.compose.animation.core.animateDpAsState
+import androidx.compose.animation.core.animateIntAsState
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.combinedClickable
+import androidx.compose.foundation.interaction.MutableInteractionSource
+import androidx.compose.foundation.interaction.collectIsPressedAsState
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.ripple.rememberRipple
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.composed
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.unit.Dp
+
+fun Modifier.squashable(
+    onClick: () -> Unit = {},
+    onLongClick: (() -> Unit)? = null,
+    enabled: Boolean = true,
+    interactionSource: MutableInteractionSource,
+    cornerRadiusRange: IntRange,
+    role: Role = Role.Button,
+) = composed {
+    val isPressed by interactionSource.collectIsPressedAsState()
+    val cornerRadius: Int by animateIntAsState(
+        targetValue = if (isPressed) cornerRadiusRange.first else cornerRadiusRange.last,
+        animationSpec = tween(easing = FastOutSlowInEasing),
+    )
+
+    Modifier
+        .clip(RoundedCornerShape(cornerRadius))
+        .combinedClickable(
+            onClick = onClick,
+            onLongClick = onLongClick,
+            interactionSource = interactionSource,
+            indication = rememberRipple(),
+            role = role,
+            enabled = enabled
+        )
+}
+
+fun Modifier.squashable(
+    onClick: () -> Unit = {},
+    onLongClick: (() -> Unit)? = null,
+    enabled: Boolean = true,
+    interactionSource: MutableInteractionSource,
+    cornerRadiusRange: ClosedRange<Dp>,
+    role: Role = Role.Button,
+) = composed {
+    val isPressed by interactionSource.collectIsPressedAsState()
+    val cornerRadius: Dp by animateDpAsState(
+        targetValue = if (isPressed) cornerRadiusRange.start else cornerRadiusRange.endInclusive,
+        animationSpec = tween(easing = FastOutSlowInEasing),
+    )
+
+    Modifier
+        .clip(RoundedCornerShape(cornerRadius))
+        .combinedClickable(
+            onClick = onClick,
+            onLongClick = onLongClick,
+            interactionSource = interactionSource,
+            indication = rememberRipple(),
+            role = role,
+            enabled = enabled
+        )
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/NavigateUpButton.kt

@@ -24,7 +24,7 @@ import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.stringResource
-import com.sadellie.unitto.core.ui.R
+import com.sadellie.unitto.core.base.R
 
 /**
  * Button that is used in Top bars

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/SegmentedButton.kt

@@ -66,7 +66,7 @@ fun RowScope.SegmentedButton(
     label: String,
     onClick: () -> Unit,
     selected: Boolean,
-    icon: ImageVector
+    icon: ImageVector? = null
 ) {
     val containerColor =
         if (selected) MaterialTheme.colorScheme.secondaryContainer else MaterialTheme.colorScheme.surface
@@ -81,14 +81,16 @@ fun RowScope.SegmentedButton(
         ),
         contentPadding = PaddingValues(horizontal = 12.dp)
     ) {
-        Crossfade(targetState = selected) {
-            if (it) {
-                Icon(Icons.Default.Check, null, Modifier.size(18.dp))
-            } else {
-                Icon(icon, null, Modifier.size(18.dp))
+        if (icon != null) {
+            Crossfade(targetState = selected) {
+                if (it) {
+                    Icon(Icons.Default.Check, null, Modifier.size(18.dp))
+                } else {
+                    Icon(icon, null, Modifier.size(18.dp))
+                }
             }
+            Spacer(Modifier.width(8.dp))
         }
-        Spacer(Modifier.width(8.dp))
         Text(label)
     }
 }

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/SettingsButton.kt

@@ -0,0 +1,34 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.outlined.Settings
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.res.stringResource
+import com.sadellie.unitto.core.base.R
+
+@Composable
+fun SettingsButton(onClick: () -> Unit) {
+    IconButton(onClick) {
+        Icon(Icons.Outlined.Settings, stringResource(R.string.open_settings_description))
+    }
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoButton.kt

@@ -19,7 +19,6 @@
 package com.sadellie.unitto.core.ui.common
 
 import androidx.compose.foundation.BorderStroke
-import androidx.compose.foundation.combinedClickable
 import androidx.compose.foundation.interaction.MutableInteractionSource
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.PaddingValues
@@ -27,8 +26,6 @@ import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.RowScope
 import androidx.compose.foundation.layout.defaultMinSize
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.shape.RoundedCornerShape
-import androidx.compose.material.ripple.rememberRipple
 import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.LocalContentColor
 import androidx.compose.material3.MaterialTheme
@@ -40,17 +37,14 @@ import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.graphics.Shape
-import androidx.compose.ui.semantics.Role
 
 @Composable
 fun UnittoButton(
     modifier: Modifier = Modifier,
     onClick: () -> Unit,
     onLongClick: (() -> Unit)? = null,
-    shape: Shape = RoundedCornerShape(100),
+    enabled: Boolean = true,
     containerColor: Color,
     contentColor: Color = contentColorFor(containerColor),
     border: BorderStroke? = null,
@@ -59,16 +53,16 @@ fun UnittoButton(
     content: @Composable RowScope.() -> Unit
 ) {
     Surface(
-        modifier = modifier.clip(shape).combinedClickable(
+        modifier = modifier.squashable(
             onClick = onClick,
             onLongClick = onLongClick,
             interactionSource = interactionSource,
-            indication = rememberRipple(),
-            role = Role.Button,
+            cornerRadiusRange = 30..50,
+            enabled = enabled
         ),
         color = containerColor,
         contentColor = contentColor,
-        border = border
+        border = border,
     ) {
         CompositionLocalProvider(LocalContentColor provides contentColor) {
             ProvideTextStyle(value = MaterialTheme.typography.labelLarge) {

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoDrawerSheet.kt

@@ -31,8 +31,8 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.core.base.TopLevelDestinations
-import com.sadellie.unitto.core.ui.R
 import com.sadellie.unitto.core.ui.model.DrawerItems
 
 @Composable

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoListItem.kt

@@ -46,7 +46,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.rotate
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
-import com.sadellie.unitto.core.ui.R
+import com.sadellie.unitto.core.base.R
 
 /**
  * Represents one item in list on Settings screen.

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoNavigationDrawer.kt

@@ -0,0 +1,195 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.gestures.AnchoredDraggableState
+import androidx.compose.foundation.gestures.DraggableAnchors
+import androidx.compose.foundation.gestures.Orientation
+import androidx.compose.foundation.gestures.anchoredDraggable
+import androidx.compose.foundation.gestures.animateTo
+import androidx.compose.foundation.gestures.detectTapGestures
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.offset
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Button
+import androidx.compose.material3.DrawerDefaults
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.IntOffset
+import androidx.compose.ui.unit.dp
+import com.sadellie.unitto.core.ui.model.DrawerItems
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+import kotlin.math.roundToInt
+
+// Why do I have to do it myself?
+@Composable
+fun UnittoModalNavigationDrawer(
+    drawer: @Composable () -> Unit,
+    modifier: Modifier,
+    state: AnchoredDraggableState<UnittoDrawerState>,
+    gesturesEnabled: Boolean,
+    scope: CoroutineScope,
+    content: @Composable () -> Unit,
+) {
+    Box(modifier.fillMaxSize()) {
+        content()
+
+        Scrim(
+            open = state.isOpen,
+            onClose = { if (gesturesEnabled) scope.launch { state.close() } },
+            fraction = {
+                fraction(state.anchors.minAnchor(), state.anchors.maxAnchor(), state.offset)
+            },
+            color = DrawerDefaults.scrimColor
+        )
+
+        // Drawer
+        Box(Modifier
+            .offset {
+                IntOffset(
+                    x = state
+                        .requireOffset()
+                        .roundToInt(), y = 0
+                )
+            }
+            .anchoredDraggable(
+                state = state,
+                orientation = Orientation.Horizontal,
+                enabled = gesturesEnabled or state.isOpen,
+            )
+            .padding(end = 18.dp) // Draggable when closed
+        ) {
+            drawer()
+        }
+
+    }
+}
+
+@Composable
+private fun Scrim(
+    open: Boolean,
+    onClose: () -> Unit,
+    fraction: () -> Float,
+    color: Color,
+) {
+    val dismissDrawer = if (open) {
+        Modifier.pointerInput(onClose) { detectTapGestures { onClose() } }
+    } else {
+        Modifier
+    }
+
+    Canvas(
+        Modifier
+            .fillMaxSize()
+            .then(dismissDrawer)
+    ) {
+        drawRect(color, alpha = fraction())
+    }
+}
+
+enum class UnittoDrawerState { OPEN, CLOSED }
+
+@Composable
+fun rememberUnittoDrawerState(
+    initialValue: UnittoDrawerState = UnittoDrawerState.CLOSED,
+): AnchoredDraggableState<UnittoDrawerState> {
+    val minValue = -with(LocalDensity.current) { 360.dp.toPx() }
+    val positionalThreshold = -minValue * 0.5f
+    val velocityThreshold = with(LocalDensity.current) { 400.dp.toPx() }
+
+    return remember {
+        AnchoredDraggableState(
+            initialValue = initialValue,
+            anchors = DraggableAnchors {
+                UnittoDrawerState.OPEN at 0F
+                UnittoDrawerState.CLOSED at minValue
+            },
+            positionalThreshold = { positionalThreshold },
+            velocityThreshold = { velocityThreshold },
+            animationSpec = tween()
+        )
+    }
+}
+
+val AnchoredDraggableState<UnittoDrawerState>.isOpen
+    get() = this.currentValue == UnittoDrawerState.OPEN
+
+suspend fun AnchoredDraggableState<UnittoDrawerState>.close() {
+    this.animateTo(UnittoDrawerState.CLOSED)
+}
+
+suspend fun AnchoredDraggableState<UnittoDrawerState>.open() {
+    this.animateTo(UnittoDrawerState.OPEN)
+}
+
+private fun fraction(a: Float, b: Float, pos: Float) =
+    ((pos - a) / (b - a)).coerceIn(0f, 1f)
+
+@Preview(backgroundColor = 0xFFC8F7D4, showBackground = true, showSystemUi = true)
+@Composable
+private fun PreviewUnittoModalNavigationDrawer() {
+    val drawerState = rememberUnittoDrawerState(initialValue = UnittoDrawerState.OPEN)
+    val corScope = rememberCoroutineScope()
+
+    UnittoModalNavigationDrawer(
+        drawer = {
+            UnittoDrawerSheet(
+                modifier = Modifier,
+                mainTabs = listOf(
+                    DrawerItems.Calculator,
+                    DrawerItems.Calculator,
+                    DrawerItems.Calculator,
+                ),
+                additionalTabs = listOf(
+                    DrawerItems.Calculator,
+                    DrawerItems.Calculator,
+                    DrawerItems.Calculator,
+                ),
+                currentDestination = DrawerItems.Calculator.destination,
+                onItemClick = {}
+            )
+        },
+        modifier = Modifier,
+        state = drawerState,
+        gesturesEnabled = true,
+        scope = corScope,
+        content = {
+            Column {
+                Text(text = "Content")
+                Button(
+                    onClick = { corScope.launch { drawerState.open() } }
+                ) {
+                    Text(text = "BUTTON")
+                }
+            }
+        }
+    )
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoSlider.kt

@@ -0,0 +1,158 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.spring
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Slider
+import androidx.compose.material3.SliderState
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.ClipOp
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Path
+import androidx.compose.ui.graphics.StrokeCap
+import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.drawscope.clipRect
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import kotlin.math.ceil
+import kotlin.math.roundToInt
+
+@Composable
+fun UnittoSlider(
+    modifier: Modifier = Modifier,
+    value: Float,
+    valueRange: ClosedFloatingPointRange<Float>,
+    onValueChange: (Float) -> Unit,
+    onValueChangeFinished: (Float) -> Unit = {}
+) {
+    val animated = animateFloatAsState(targetValue = value)
+
+    Slider(
+        value = animated.value,
+        onValueChange = onValueChange,
+        modifier = modifier,
+        valueRange = valueRange,
+        onValueChangeFinished = { onValueChangeFinished(animated.value) },
+        track = { sliderPosition -> SquigglyTrack(sliderPosition) },
+        steps = valueRange.endInclusive.roundToInt(),
+    )
+}
+
+@Composable
+private fun SquigglyTrack(
+    sliderState: SliderState,
+    eachWaveWidth: Float = 80f,
+    strokeWidth: Float = 15f,
+    filledColor: Color = MaterialTheme.colorScheme.primary,
+    unfilledColor: Color = MaterialTheme.colorScheme.surfaceVariant
+) {
+    val coroutineScope = rememberCoroutineScope()
+    var direct by remember { mutableFloatStateOf(0.72f) }
+    val animatedDirect = animateFloatAsState(direct, spring(stiffness = Spring.StiffnessLow))
+    val slider = sliderState.valueRange.endInclusive
+
+    LaunchedEffect(sliderState.valueRange.endInclusive) {
+        coroutineScope.launch {
+            delay(200L)
+            direct *= -1
+        }
+    }
+
+    Canvas(
+        modifier = Modifier
+            .fillMaxWidth()
+            .height(20.dp)
+    ) {
+        val width = size.width
+        val height = size.height
+
+        val path = Path().apply {
+            moveTo(
+                x = strokeWidth / 2,
+                y = height.times(0.5f)
+            )
+            val amount = ceil(width.div(eachWaveWidth))
+
+            repeat(amount.toInt()) {
+                val peek = if (it % 2 == 0) animatedDirect.value else -animatedDirect.value
+
+                relativeQuadraticBezierTo(
+                    dx1 = eachWaveWidth * 0.5f,
+                    // 0.75, because 1.0 was clipping out of bound for some reason
+                    dy1 = height.times(peek),
+                    dx2 = eachWaveWidth,
+                    dy2 = 0f
+                )
+            }
+        }
+
+        clipRect(
+            top = 0f,
+            left = 0f,
+            right = width.times(slider),
+            bottom = height,
+            clipOp = ClipOp.Intersect
+        ) {
+            drawPath(
+                path = path,
+                color = filledColor,
+                style = Stroke(strokeWidth, cap = StrokeCap.Round)
+            )
+        }
+
+        drawLine(
+            color = unfilledColor,
+            start = Offset(width.times(slider), height.times(0.5f)),
+            end = Offset(width, height.times(0.5f)),
+            strokeWidth = strokeWidth,
+            cap = StrokeCap.Round
+        )
+    }
+}
+
+@Preview(device = "spec:width=411dp,height=891dp")
+@Preview(device = "spec:width=673.5dp,height=841dp,dpi=480")
+@Preview(device = "spec:width=1280dp,height=800dp,dpi=480")
+@Preview(device = "spec:width=1920dp,height=1080dp,dpi=480")
+@Composable
+private fun PreviewNewSlider() {
+    var currentValue by remember { mutableFloatStateOf(0.9f) }
+
+    UnittoSlider(
+        value = currentValue,
+        valueRange = 0f..1f,
+        onValueChange = { currentValue = it }
+    )
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/CursorFixer.kt

@@ -0,0 +1,73 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common.textfield
+
+import com.sadellie.unitto.core.base.Token
+import kotlin.math.abs
+
+fun String.fixCursor(pos: Int, grouping: String): Int {
+
+    if (isEmpty()) return pos
+
+    // Best position if we move cursor left
+    var leftCursor = pos
+    while (this.isPlacedIllegallyAt(leftCursor, grouping)) leftCursor--
+
+    // Best position if we move cursor right
+    var rightCursor = pos
+    while (this.isPlacedIllegallyAt(rightCursor, grouping)) rightCursor++
+
+    return listOf(leftCursor, rightCursor).minBy { abs(it - pos) }
+}
+
+fun String.tokenLengthAhead(pos: Int): Int {
+    Token.Func.allWithOpeningBracket.forEach {
+        if (pos.isAfterToken(this, it)) return it.length
+    }
+
+    return 1
+}
+
+private fun String.isPlacedIllegallyAt(pos: Int, grouping: String): Boolean {
+    // For things like "123,|456" - this is illegal
+    if (pos.isAfterToken(this, grouping)) return true
+
+    // For things like "123,456+c|os(8)" - this is illegal
+    Token.Func.allWithOpeningBracket.forEach {
+        if (pos.isAtToken(this, it)) return true
+    }
+
+    return false
+}
+
+private fun Int.isAtToken(str: String, token: String): Boolean {
+    val checkBound = (token.length - 1).coerceAtLeast(1)
+    return str
+        .substring(
+            startIndex = (this - checkBound).coerceAtLeast(0),
+            endIndex = (this + checkBound).coerceAtMost(str.length)
+        )
+        .contains(token)
+}
+
+private fun Int.isAfterToken(str: String, token: String): Boolean {
+    return str
+        .substring((this - token.length).coerceAtLeast(0), this)
+        .contains(token)
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/ExpressionTransformer.kt

@@ -0,0 +1,82 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common.textfield
+
+import androidx.compose.ui.text.AnnotatedString
+import androidx.compose.ui.text.input.OffsetMapping
+import androidx.compose.ui.text.input.TransformedText
+import androidx.compose.ui.text.input.VisualTransformation
+
+class ExpressionTransformer(private val formatterSymbols: FormatterSymbols) : VisualTransformation {
+
+    override fun filter(text: AnnotatedString): TransformedText {
+        val formatted = text.text.formatExpression(formatterSymbols)
+        return TransformedText(
+            text = AnnotatedString(formatted),
+            offsetMapping = ExpressionMapping(text.text, formatted)
+        )
+    }
+
+    inner class ExpressionMapping(
+        private val original: String,
+        private val transformed: String
+    ) : OffsetMapping {
+        // Called when entering text (on each text change)
+        // Basically moves cursor to the right position
+        //
+        // original input is "1000" and cursor is placed at the end "1000|"
+        // the transformed is "1,000" where cursor should be? - "1,000|"
+        override fun originalToTransformed(offset: Int): Int {
+            if (offset <= 0) return 0
+            if (offset >= original.length) return transformed.length
+
+            val unformattedSubstr = original.take(offset)
+            var buffer = ""
+            var groupings = 0
+
+            run {
+                transformed.forEach {
+                    when (it) {
+                        formatterSymbols.grouping.first() -> groupings++
+                        formatterSymbols.fractional.first() -> buffer += "."
+                        else -> buffer += it
+                    }
+                    if (buffer == unformattedSubstr) return@run
+                }
+            }
+
+            return transformed.fixCursor(buffer.length + groupings, formatterSymbols.grouping)
+        }
+
+        // Called when clicking transformed text
+        // Snaps cursor to the right position
+        //
+        // the transformed is "1,000" and cursor is placed at the end "1,000|"
+        // original input is "1000" where cursor should be? - "1000|"
+        override fun transformedToOriginal(offset: Int): Int {
+            if (offset <= 0) return 0
+            if (offset >= transformed.length) return original.length
+
+            val grouping = formatterSymbols.grouping.first()
+            val fixedCursor = transformed.fixCursor(offset, formatterSymbols.grouping)
+            val addedSymbols = transformed.take(fixedCursor).count { it == grouping }
+            return fixedCursor - addedSymbols
+        }
+    }
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/FormatterExtensions.kt

@@ -0,0 +1,193 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common.textfield
+
+import android.content.Context
+import com.sadellie.unitto.core.base.R
+import com.sadellie.unitto.core.base.Token
+import java.math.BigDecimal
+import java.math.RoundingMode
+
+private val numbersRegex by lazy { Regex("[\\d.]+") }
+
+private val timeDivisions by lazy {
+    mapOf(
+        R.string.day_short to BigDecimal("86400000000000000000000"),
+        R.string.hour_short to BigDecimal("3600000000000000000000"),
+        R.string.minute_short to BigDecimal("60000000000000000000"),
+        R.string.second_short to BigDecimal("1000000000000000000"),
+        R.string.millisecond_short to BigDecimal("1000000000000000"),
+        R.string.microsecond_short to BigDecimal("1000000000000"),
+        R.string.nanosecond_short to BigDecimal("1000000000"),
+        R.string.attosecond_short to BigDecimal("1"),
+    )
+}
+
+fun String.clearAndFilterExpression(formatterSymbols: FormatterSymbols): String {
+    var clean = this
+        .replace(formatterSymbols.grouping, "")
+        .replace(formatterSymbols.fractional, Token.Digit.dot)
+        .replace(" ", "")
+
+    Token.sexyToUgly.forEach { (token, ugliness) ->
+        ugliness.forEach {
+            clean = clean.replace(it, token)
+        }
+    }
+
+    return clean.cleanIt(Token.expressionTokens)
+}
+
+internal fun String.clearAndFilterNumberBase(): String {
+    return uppercase().cleanIt(Token.numberBaseTokens)
+}
+
+/**
+ * Format string time conversion result into a more readable format.
+ *
+ * @param basicUnit Basic unit of the unit we convert to
+ * @return String like "1d 12h 12s".
+ */
+fun String.formatTime(
+    context: Context,
+    basicUnit: BigDecimal?,
+    formatterSymbols: FormatterSymbols
+): String {
+    // We get ugly version of input (non-fancy minus)
+    val input = this
+
+    if (basicUnit == null) return Token.Digit._0
+
+    try {
+        // Don't need magic if the input is zero
+        if (BigDecimal(input).compareTo(BigDecimal.ZERO) == 0) return Token.Digit._0
+    } catch (e: NumberFormatException) {
+        // For case such as "10-" and "("
+        return Token.Digit._0
+    }
+    // Attoseconds don't need "magic"
+    if (basicUnit.compareTo(BigDecimal.ONE) == 0) return input.formatExpression(formatterSymbols)
+
+    var result = if (input.startsWith("-")) Token.Operator.minus else ""
+    var remainingSeconds = BigDecimal(input)
+        .abs()
+        .multiply(basicUnit)
+        .setScale(0, RoundingMode.HALF_EVEN)
+
+    if (remainingSeconds.compareTo(BigDecimal.ZERO) == 0) return Token.Digit._0
+
+    timeDivisions.forEach { (timeStr, divider) ->
+        val division = remainingSeconds.divideAndRemainder(divider)
+        val time = division.component1()
+        remainingSeconds = division.component2()
+        if (time.compareTo(BigDecimal.ZERO) != 0) {
+            result += "${time.toPlainString().formatExpression(formatterSymbols)}${context.getString(timeStr)} "
+        }
+    }
+    return result.trimEnd()
+}
+
+fun String.formatExpression(
+    formatterSymbols: FormatterSymbols
+): String {
+    var input = this
+    // Don't do anything to engineering string.
+    if (input.contains(Token.DisplayOnly.engineeringE)) {
+        return input.replace(Token.Digit.dot, formatterSymbols.fractional)
+    }
+
+    numbersRegex
+        .findAll(input)
+        .map(MatchResult::value)
+        .forEach {
+            input = input.replace(it, it.formatNumber(formatterSymbols))
+        }
+
+    Token.sexyToUgly.forEach { (token, ugliness) ->
+        ugliness.forEach { uglySymbol ->
+            input = input.replace(uglySymbol, token)
+        }
+    }
+
+    return input
+}
+
+private fun String.formatNumber(
+    formatterSymbols: FormatterSymbols
+): String {
+    val input = this
+
+    if (input.any { it.isLetter() }) return input
+
+    var firstPart = input.takeWhile { it != '.' }
+    val remainingPart = input.removePrefix(firstPart)
+
+    // Number of empty symbols (spaces) we need to add to correctly split into chunks.
+    val offset = 3 - firstPart.length.mod(3)
+    val output = if (offset != 3) {
+        // We add some spaces at the beginning so that last chunk has 3 symbols
+        firstPart = " ".repeat(offset) + firstPart
+        firstPart.chunked(3).joinToString(formatterSymbols.grouping).drop(offset)
+    } else {
+        firstPart.chunked(3).joinToString(formatterSymbols.grouping)
+    }
+
+    return output.plus(remainingPart.replace(".", formatterSymbols.fractional))
+}
+
+private fun String.cleanIt(legalTokens: List<String>): String {
+    val streamOfTokens = this
+
+    fun peekTokenAfter(cursor: Int): String? {
+        legalTokens.forEach { token ->
+            val subs = streamOfTokens
+                .substring(
+                    cursor,
+                    (cursor + token.length).coerceAtMost(streamOfTokens.length)
+                )
+            if (subs == token) {
+                // Got a digit, see if there are other digits coming after
+                if (token in Token.Digit.allWithDot) {
+                    return streamOfTokens
+                        .substring(cursor)
+                        .takeWhile { Token.Digit.allWithDot.contains(it.toString()) }
+                }
+                return token
+            }
+        }
+        return null
+    }
+
+    var cursor = 0
+    var tokens = ""
+
+    while (cursor != streamOfTokens.length) {
+        val nextToken = peekTokenAfter(cursor)
+
+        if (nextToken != null) {
+            tokens += nextToken
+            cursor += nextToken.length
+        } else {
+            // Didn't find any token, move left slowly (by 1 symbol)
+            cursor++
+        }
+    }
+
+    return tokens
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/FormatterSymbols.kt

@@ -0,0 +1,46 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common.textfield
+
+import com.sadellie.unitto.core.base.Separator
+
+sealed class FormatterSymbols(val grouping: String, val fractional: String) {
+    object Spaces : FormatterSymbols(" ", ".")
+    object Period : FormatterSymbols(".", ",")
+    object Comma : FormatterSymbols(",", ".")
+}
+
+object AllFormatterSymbols {
+    private val allFormatterSymbols by lazy {
+        hashMapOf(
+            Separator.SPACE to FormatterSymbols.Spaces,
+            Separator.PERIOD to FormatterSymbols.Period,
+            Separator.COMMA to FormatterSymbols.Comma
+        )
+    }
+
+    /**
+     * Defaults to [FormatterSymbols.Spaces] if not found.
+     *
+     * @see Separator
+     */
+    fun getById(separator: Int): FormatterSymbols {
+        return allFormatterSymbols.getOrElse(separator) { FormatterSymbols.Spaces }
+    }
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/InputTextField.kt

@@ -24,6 +24,7 @@ import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.foundation.layout.widthIn
 import androidx.compose.foundation.text.BasicTextField
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.getValue
@@ -54,105 +55,124 @@ import androidx.compose.ui.text.TextRange
 import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.font.createFontFamilyResolver
 import androidx.compose.ui.text.input.TextFieldValue
+import androidx.compose.ui.text.input.VisualTransformation
 import androidx.compose.ui.unit.Constraints
 import androidx.compose.ui.unit.TextUnit
 import androidx.compose.ui.unit.sp
-import com.sadellie.unitto.core.base.Separator
-import com.sadellie.unitto.core.ui.Formatter
 import com.sadellie.unitto.core.ui.theme.NumbersTextStyleDisplayLarge
 import kotlin.math.ceil
 import kotlin.math.roundToInt
 
 @Composable
-fun InputTextField(
+fun ExpressionTextField(
     modifier: Modifier,
     value: TextFieldValue,
-    textStyle: TextStyle = NumbersTextStyleDisplayLarge,
     minRatio: Float = 1f,
-    cutCallback: () -> Unit,
-    pasteCallback: (String) -> Unit,
-    onCursorChange: (IntRange) -> Unit,
+    cutCallback: () -> Unit = {},
+    pasteCallback: (String) -> Unit = {},
+    onCursorChange: (TextRange) -> Unit,
     textColor: Color = MaterialTheme.colorScheme.onSurfaceVariant,
+    formatterSymbols: FormatterSymbols,
+    readOnly: Boolean = false,
+    placeholder: String? = null,
 ) {
-    val clipboardManager = LocalClipboardManager.current
-    fun copyCallback() = clipboardManager.copyWithoutGrouping(value)
-
-    val textToolbar = UnittoTextToolbar(
-        view = LocalView.current,
-        copyCallback = ::copyCallback,
-        pasteCallback = {
-            pasteCallback(
-                Formatter.toSeparator(
-                    clipboardManager.getText()?.text ?: "", Separator.COMMA
-                )
-            )
-        },
-        cutCallback = {
-            copyCallback()
-            cutCallback()
-            onCursorChange(value.selection.end..value.selection.end)
-        }
-    )
-
-    CompositionLocalProvider(
-        LocalTextInputService provides null,
-        LocalTextToolbar provides textToolbar
-    ) {
-        AutoSizableTextField(
-            modifier = modifier,
-            value = value,
-            textStyle = textStyle.copy(color = textColor),
-            minRatio = minRatio,
-            onValueChange = {
-                onCursorChange(it.selection.start..it.selection.end)
-            },
-            showToolbar = textToolbar::showMenu,
-            hideToolbar = textToolbar::hide
-        )
-    }
-}
-
-@Composable
-fun InputTextField(
-    modifier: Modifier = Modifier,
-    value: String,
-    textStyle: TextStyle = NumbersTextStyleDisplayLarge,
-    minRatio: Float = 1f,
-    textColor: Color = MaterialTheme.colorScheme.onSurfaceVariant,
-    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() }
-) {
-    var textFieldValue by remember(value) {
-        mutableStateOf(TextFieldValue(value, selection = TextRange(value.length)))
-    }
     val clipboardManager = LocalClipboardManager.current
     fun copyCallback() {
-        clipboardManager.copyWithoutGrouping(textFieldValue)
-        textFieldValue = textFieldValue.copy(selection = TextRange(textFieldValue.selection.end))
+        clipboardManager.copyWithoutGrouping(value, formatterSymbols)
+        onCursorChange(TextRange(value.selection.end))
     }
 
-    CompositionLocalProvider(
-        LocalTextInputService provides null,
-        LocalTextToolbar provides UnittoTextToolbar(
+    val textToolbar: UnittoTextToolbar = if (readOnly) {
+        UnittoTextToolbar(
             view = LocalView.current,
             copyCallback = ::copyCallback,
         )
-    ) {
-        AutoSizableTextField(
-            modifier = modifier,
-            value = textFieldValue,
-            onValueChange = { textFieldValue = it },
-            textStyle = textStyle.copy(color = textColor),
-            minRatio = minRatio,
-            readOnly = true,
-            interactionSource = interactionSource
+    } else {
+        UnittoTextToolbar(
+            view = LocalView.current,
+            copyCallback = ::copyCallback,
+            pasteCallback = {
+                pasteCallback(clipboardManager.getText()?.text?.clearAndFilterExpression(formatterSymbols) ?: "")
+            },
+            cutCallback = {
+                clipboardManager.copyWithoutGrouping(value, formatterSymbols)
+                cutCallback()
+            }
         )
     }
+
+    AutoSizableTextField(
+        modifier = modifier,
+        value = value,
+        formattedValue = value.text.formatExpression(formatterSymbols),
+        textStyle = NumbersTextStyleDisplayLarge.copy(color = textColor),
+        minRatio = minRatio,
+        onValueChange = { onCursorChange(it.selection) },
+        readOnly = readOnly,
+        showToolbar = textToolbar::showMenu,
+        hideToolbar = textToolbar::hide,
+        visualTransformation = ExpressionTransformer(formatterSymbols),
+        placeholder = placeholder,
+        textToolbar = textToolbar
+    )
+}
+
+@Composable
+fun UnformattedTextField(
+    modifier: Modifier,
+    value: TextFieldValue,
+    minRatio: Float = 1f,
+    cutCallback: () -> Unit = {},
+    pasteCallback: (String) -> Unit = {},
+    onCursorChange: (TextRange) -> Unit,
+    textColor: Color = MaterialTheme.colorScheme.onSurfaceVariant,
+    readOnly: Boolean = false,
+    placeholder: String? = null,
+) {
+    val clipboardManager = LocalClipboardManager.current
+    fun copyCallback() {
+        clipboardManager.copy(value)
+        onCursorChange(TextRange(value.selection.end))
+    }
+
+    val textToolbar: UnittoTextToolbar = if (readOnly) {
+        UnittoTextToolbar(
+            view = LocalView.current,
+            copyCallback = ::copyCallback,
+        )
+    } else {
+        UnittoTextToolbar(
+            view = LocalView.current,
+            copyCallback = ::copyCallback,
+            pasteCallback = {
+                pasteCallback(clipboardManager.getText()?.text?.clearAndFilterNumberBase() ?: "")
+            },
+            cutCallback = {
+                clipboardManager.copy(value)
+                cutCallback()
+            }
+        )
+    }
+
+    AutoSizableTextField(
+        modifier = modifier,
+        value = value,
+        textStyle = NumbersTextStyleDisplayLarge.copy(color = textColor),
+        minRatio = minRatio,
+        onValueChange = { onCursorChange(it.selection) },
+        readOnly = readOnly,
+        showToolbar = textToolbar::showMenu,
+        hideToolbar = textToolbar::hide,
+        placeholder = placeholder,
+        textToolbar = textToolbar
+    )
 }
 
 @Composable
 private fun AutoSizableTextField(
     modifier: Modifier = Modifier,
     value: TextFieldValue,
+    formattedValue: String = value.text,
     textStyle: TextStyle = TextStyle(),
     scaleFactor: Float = 0.95f,
     minRatio: Float = 1f,
@@ -160,11 +180,14 @@ private fun AutoSizableTextField(
     readOnly: Boolean = false,
     showToolbar: (rect: Rect) -> Unit = {},
     hideToolbar: () -> Unit = {},
-    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() }
+    visualTransformation: VisualTransformation = VisualTransformation.None,
+    placeholder: String? = null,
+    textToolbar: UnittoTextToolbar
 ) {
     val focusRequester = remember { FocusRequester() }
     val density = LocalDensity.current
 
+    val textValue = value.copy(value.text.take(2000))
     var nFontSize: TextUnit by remember { mutableStateOf(0.sp) }
     var minFontSize: TextUnit
 
@@ -174,14 +197,14 @@ private fun AutoSizableTextField(
     ) {
         with(density) {
             // Cursor handle is not visible without this, 0.836f is the minimum required factor here
-            nFontSize = maxHeight.toSp() * 0.836f
+            nFontSize = maxHeight.toSp() * 0.835f
             minFontSize = nFontSize * minRatio
         }
 
         // Modified: https://blog.canopas.com/autosizing-textfield-in-jetpack-compose-7a80f0270853
         val calculateParagraph = @Composable {
             Paragraph(
-                text = value.text,
+                text = formattedValue,
                 style = textStyle.copy(fontSize = nFontSize),
                 constraints = Constraints(
                     maxWidth = ceil(with(density) { maxWidth.toPx() }).toInt()
@@ -210,45 +233,70 @@ private fun AutoSizableTextField(
         )
         var offset = Offset.Zero
 
-        BasicTextField(
-            value = value,
-            onValueChange = {
-                showToolbar(Rect(offset, 0f))
-                hideToolbar()
-                onValueChange(it)
-            },
-            modifier = Modifier
-                .focusRequester(focusRequester)
-                .clickable(
-                    interactionSource = remember { MutableInteractionSource() },
-                    indication = null,
-                    onClick = {
-                        hideToolbar()
-                        focusRequester.requestFocus()
-                        onValueChange(value.copy(selection = TextRange.Zero))
-                        showToolbar(Rect(offset, 0f))
+        CompositionLocalProvider(
+            LocalTextInputService provides null,
+            LocalTextToolbar provides textToolbar
+        ) {
+            BasicTextField(
+                value = textValue,
+                onValueChange = {
+                    showToolbar(Rect(offset, 0f))
+                    hideToolbar()
+                    onValueChange(it)
+                },
+                modifier = Modifier
+                    .focusRequester(focusRequester)
+                    .clickable(
+                        interactionSource = remember { MutableInteractionSource() },
+                        indication = null,
+                        onClick = {
+                            hideToolbar()
+                            focusRequester.requestFocus()
+                            onValueChange(value.copy(selection = TextRange.Zero))
+                            showToolbar(Rect(offset, 0f))
+                        }
+                    )
+                    .widthIn(max = with(density) { intrinsics.width.toDp() })
+                    .layout { measurable, constraints ->
+                        val placeable = measurable.measure(constraints)
+                        // TextField size is changed with a delay (text jumps). Here we correct it.
+                        layout(placeable.width, placeable.height) {
+                            placeable.place(
+                                x = (intrinsics.width - intrinsics.maxIntrinsicWidth)
+                                    .coerceAtLeast(0f)
+                                    .roundToInt(),
+                                y = (placeable.height - intrinsics.height).roundToInt()
+                            )
+                        }
                     }
-                )
-                .widthIn(max = with(density) { intrinsics.width.toDp() })
-                .layout { measurable, constraints ->
-                    val placeable = measurable.measure(constraints)
-                    // TextField size is changed with a delay (text jumps). Here we correct it.
-                    layout(placeable.width, placeable.height) {
-                        placeable.place(
-                            x = (intrinsics.width - intrinsics.maxIntrinsicWidth)
-                                .coerceAtLeast(0f)
-                                .roundToInt(),
-                            y = (placeable.height - intrinsics.height).roundToInt()
+                    .onGloballyPositioned { layoutCoords ->
+                        offset = layoutCoords.positionInWindow()
+                    },
+                textStyle = nTextStyle,
+                cursorBrush = SolidColor(MaterialTheme.colorScheme.onSurfaceVariant),
+                singleLine = true,
+                readOnly = readOnly,
+                visualTransformation = visualTransformation,
+                decorationBox = { innerTextField ->
+                    if (textValue.text.isEmpty() and !placeholder.isNullOrEmpty()) {
+                        Text(
+                            text = placeholder!!, // It's not null, i swear
+                            style = nTextStyle,
+                            color = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.5f),
+                            modifier = Modifier.layout { measurable, constraints ->
+                                val placeable = measurable.measure(constraints)
+
+                                layout(placeable.width, placeable.height) {
+                                    placeable.place(x = -placeable.width, y = 0)
+                                }
+                            }
                         )
                     }
+
+                    innerTextField()
                 }
-                .onGloballyPositioned { layoutCoords -> offset = layoutCoords.positionInWindow() },
-            textStyle = nTextStyle,
-            cursorBrush = SolidColor(MaterialTheme.colorScheme.onSurfaceVariant),
-            singleLine = true,
-            readOnly = readOnly,
-            interactionSource = interactionSource
-        )
+            )
+        }
     }
 }
 
@@ -260,8 +308,22 @@ private fun AutoSizableTextField(
  *
  * @param value Formatted value that has grouping symbols.
  */
-fun ClipboardManager.copyWithoutGrouping(value: TextFieldValue) = this.setText(
+fun ClipboardManager.copyWithoutGrouping(
+    value: TextFieldValue,
+    formatterSymbols: FormatterSymbols
+) = this.setText(
     AnnotatedString(
-        Formatter.removeGrouping(value.annotatedString.subSequence(value.selection).text)
+        value.annotatedString
+            .subSequence(value.selection)
+            .text
+            .replace(formatterSymbols.grouping, "")
+    )
+)
+
+fun ClipboardManager.copy(value: TextFieldValue) = this.setText(
+    AnnotatedString(
+        value.annotatedString
+            .subSequence(value.selection)
+            .text
     )
 )

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/textfield/TextFieldValueExtensions.kt

@@ -0,0 +1,59 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common.textfield
+
+import androidx.compose.ui.text.TextRange
+import androidx.compose.ui.text.input.TextFieldValue
+
+fun TextFieldValue.addTokens(tokens: String): TextFieldValue {
+    return this.copy(
+        text = text.replaceRange(selection.start, selection.end, tokens),
+        selection = TextRange(selection.start + tokens.length)
+    )
+}
+
+fun TextFieldValue.deleteTokens(): TextFieldValue {
+    val distanceFromEnd = text.length - selection.end
+
+    val deleteRangeStart = when (selection.end) {
+        // Don't delete if at the start of the text field
+        0 -> return this
+        // We don't have anything selected (cursor in one position)
+        // like this 1234|56 => after deleting will be like this 123|56
+        // Cursor moved one symbol left
+        selection.start -> {
+            // We default to 1 here. It means that cursor is not placed after illegal token
+            // Just a number or a binary operator or something else, can delete by one symbol
+            val symbolsToDelete = text.tokenLengthAhead(selection.end)
+
+            selection.start - symbolsToDelete
+        }
+        // We have multiple symbols selected
+        // like this 123[45]6 => after deleting will be like this 123|6
+        // Cursor will be placed where selection start was
+        else -> selection.start
+    }
+
+    val newText = text.removeRange(deleteRangeStart, selection.end)
+
+    return this.copy(
+        text = newText,
+        selection = TextRange((newText.length - distanceFromEnd).coerceAtLeast(0))
+    )
+}

core/ui/src/main/java/com/sadellie/unitto/core/ui/model/DrawerItems.kt

@@ -20,9 +20,11 @@ package com.sadellie.unitto.core.ui.model
 
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Calculate
+import androidx.compose.material.icons.filled.Event
 import androidx.compose.material.icons.filled.Settings
 import androidx.compose.material.icons.filled.SwapHoriz
 import androidx.compose.material.icons.outlined.Calculate
+import androidx.compose.material.icons.outlined.Event
 import androidx.compose.material.icons.outlined.Settings
 import androidx.compose.material.icons.outlined.SwapHoriz
 import androidx.compose.ui.graphics.vector.ImageVector
@@ -45,6 +47,12 @@ sealed class DrawerItems(
         defaultIcon = Icons.Outlined.SwapHoriz
     )
 
+    object DateDifference : DrawerItems(
+        destination = TopLevelDestinations.DateDifference,
+        selectedIcon = Icons.Filled.Event,
+        defaultIcon = Icons.Outlined.Event
+    )
+
     object Settings : DrawerItems(
         destination = TopLevelDestinations.Settings,
         selectedIcon = Icons.Filled.Settings,

core/ui/src/main/java/com/sadellie/unitto/core/ui/theme/Type.kt

@@ -25,7 +25,7 @@ import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.em
 import androidx.compose.ui.unit.sp
-import com.sadellie.unitto.core.ui.R
+import com.sadellie.unitto.core.base.R
 
 private val Montserrat = FontFamily(
     Font(R.font.montserrat_light, weight = FontWeight.Light),

core/ui/src/test/java/com/sadellie/unitto/core/ui/ExpressionTransformerTest.kt

@@ -0,0 +1,68 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui
+
+import com.sadellie.unitto.core.ui.common.textfield.ExpressionTransformer
+import com.sadellie.unitto.core.ui.common.textfield.FormatterSymbols
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+class ExpressionTransformerTest {
+
+    private val expr = ExpressionTransformer(FormatterSymbols.Comma)
+
+    private fun origToTrans(orig: String, trans: String, offset: Int): Int =
+        expr.ExpressionMapping(orig, trans).originalToTransformed(offset)
+
+    private fun transToOrig(trans: String, orig: String, offset: Int): Int =
+        expr.ExpressionMapping(orig, trans).transformedToOriginal(offset)
+
+    @Test
+    fun `test 1234`() {
+        // at the start
+        assertEquals(0, origToTrans("1,234", "1234", 0))
+        assertEquals(0, transToOrig("1,234", "1234", 0))
+
+        // somewhere in inside, no offset needed
+        assertEquals(1, origToTrans("1234", "1,234", 1))
+        assertEquals(1, transToOrig("1,234", "1234", 1))
+
+        // somewhere in inside, offset needed
+        assertEquals(1, transToOrig("1,234", "1234", 2))
+
+        // at the end
+        assertEquals(5, origToTrans("1234", "1,234", 4))
+        assertEquals(4, transToOrig("1,234", "1234", 5))
+    }
+
+    @Test
+    fun `test 123`() {
+        // at the start
+        assertEquals(0, origToTrans("123", "123", 0))
+        assertEquals(0, transToOrig("123", "123", 0))
+
+        // somewhere in inside
+        assertEquals(1, origToTrans("123", "123", 1))
+        assertEquals(1, transToOrig("123", "123", 1))
+
+        // at the end
+        assertEquals(3, origToTrans("123", "123", 3))
+        assertEquals(3, transToOrig("123", "123", 3))
+    }
+}

core/ui/src/test/java/com/sadellie/unitto/core/ui/FormatterTest.kt

@@ -20,7 +20,9 @@ package com.sadellie.unitto.core.ui
 
 import android.content.Context
 import androidx.compose.ui.test.junit4.createComposeRule
-import com.sadellie.unitto.core.base.Separator
+import com.sadellie.unitto.core.ui.common.textfield.FormatterSymbols
+import com.sadellie.unitto.core.ui.common.textfield.formatExpression
+import com.sadellie.unitto.core.ui.common.textfield.formatTime
 import org.junit.Assert.assertEquals
 import org.junit.Rule
 import org.junit.Test
@@ -29,16 +31,14 @@ import org.robolectric.RobolectricTestRunner
 import org.robolectric.RuntimeEnvironment
 import java.math.BigDecimal
 
-private val formatter = Formatter
-
 private const val ENG_VALUE = "123E+21"
 private const val ENG_VALUE_FRACTIONAL = "123.3E+21"
 private const val COMPLETE_VALUE = "123456.789"
 private const val INCOMPLETE_VALUE = "123456."
 private const val NO_FRACTIONAL_VALUE = "123456"
-private const val INCOMPLETE_EXPR = "50+123456÷8×0.8–12+"
-private const val COMPLETE_EXPR = "50+123456÷8×0.8–12+0-√9*4^9+2×(9+8×7)"
-private const val LONG_HALF_COMPLETE_EXPR = "50+123456÷89078..9×0.8–12+0-√9*4^9+2×(9+8×7)×sin(13sin123cos"
+private const val INCOMPLETE_EXPR = "50+123456÷8×0.8-12+"
+private const val COMPLETE_EXPR = "50+123456÷8×0.8-12+0-√9×4^9+2×(9+8×7)"
+private const val LONG_HALF_COMPLETE_EXPR = "50+123456÷89078..9×0.8-12+0-√9×4^9+2×(9+8×7)×sin(13sin123cos"
 private const val SOME_BRACKETS = "(((((((("
 
 @RunWith(RobolectricTestRunner::class)
@@ -49,167 +49,143 @@ class FormatterTest {
 
     @Test
     fun setSeparatorSpaces() {
-        formatter.setSeparator(Separator.SPACES)
-        assertEquals(".", formatter.fractional)
-        assertEquals("123E+21", formatter.format(ENG_VALUE))
-        assertEquals("123.3E+21", formatter.format(ENG_VALUE_FRACTIONAL))
-        assertEquals("123 456.789", formatter.format(COMPLETE_VALUE))
-        assertEquals("123 456.", formatter.format(INCOMPLETE_VALUE))
-        assertEquals("123 456", formatter.format(NO_FRACTIONAL_VALUE))
-        assertEquals("50+123 456÷8×0.8–12+", formatter.format(INCOMPLETE_EXPR))
-        assertEquals("50+123 456÷8×0.8–12+0–√9×4^9+2×(9+8×7)", formatter.format(COMPLETE_EXPR))
-        assertEquals("50+123 456÷89 078..9×0.8–12+0–√9×4^9+2×(9+8×7)×sin(13sin123cos", formatter.format(LONG_HALF_COMPLETE_EXPR))
-        assertEquals("((((((((", formatter.format(SOME_BRACKETS))
+        fun String.format(): String = formatExpression(FormatterSymbols.Spaces)
+        assertEquals("123E+21", ENG_VALUE.format())
+        assertEquals("123.3E+21", ENG_VALUE_FRACTIONAL.format())
+        assertEquals("123 456.789", COMPLETE_VALUE.format())
+        assertEquals("123 456.", INCOMPLETE_VALUE.format())
+        assertEquals("123 456", NO_FRACTIONAL_VALUE.format())
+        assertEquals("50+123 456÷8×0.8−12+", INCOMPLETE_EXPR.format())
+        assertEquals("50+123 456÷8×0.8−12+0−√9×4^9+2×(9+8×7)", COMPLETE_EXPR.format())
+        assertEquals("50+123 456÷89 078..9×0.8−12+0−√9×4^9+2×(9+8×7)×sin(13sin123cos", LONG_HALF_COMPLETE_EXPR.format())
+        assertEquals("((((((((", SOME_BRACKETS.format())
     }
 
     @Test
     fun setSeparatorComma() {
-        formatter.setSeparator(Separator.COMMA)
-        assertEquals(".", formatter.fractional)
-        assertEquals("123E+21", formatter.format(ENG_VALUE))
-        assertEquals("123.3E+21", formatter.format(ENG_VALUE_FRACTIONAL))
-        assertEquals("123,456.789", formatter.format(COMPLETE_VALUE))
-        assertEquals("123,456.", formatter.format(INCOMPLETE_VALUE))
-        assertEquals("123,456", formatter.format(NO_FRACTIONAL_VALUE))
-        assertEquals("50+123,456÷8×0.8–12+", formatter.format(INCOMPLETE_EXPR))
-        assertEquals("50+123,456÷8×0.8–12+0–√9×4^9+2×(9+8×7)", formatter.format(COMPLETE_EXPR))
-        assertEquals("50+123,456÷89,078..9×0.8–12+0–√9×4^9+2×(9+8×7)×sin(13sin123cos", formatter.format(LONG_HALF_COMPLETE_EXPR))
-        assertEquals("((((((((", formatter.format(SOME_BRACKETS))
+        fun String.format(): String = formatExpression(FormatterSymbols.Comma)
+        assertEquals("123E+21", ENG_VALUE.format())
+        assertEquals("123.3E+21", ENG_VALUE_FRACTIONAL.format())
+        assertEquals("123,456.789", COMPLETE_VALUE.format())
+        assertEquals("123,456.", INCOMPLETE_VALUE.format())
+        assertEquals("123,456", NO_FRACTIONAL_VALUE.format())
+        assertEquals("50+123,456÷8×0.8−12+", INCOMPLETE_EXPR.format())
+        assertEquals("50+123,456÷8×0.8−12+0−√9×4^9+2×(9+8×7)", COMPLETE_EXPR.format())
+        assertEquals("50+123,456÷89,078..9×0.8−12+0−√9×4^9+2×(9+8×7)×sin(13sin123cos", LONG_HALF_COMPLETE_EXPR.format())
+        assertEquals("((((((((", SOME_BRACKETS.format())
     }
 
     @Test
     fun setSeparatorPeriod() {
-        formatter.setSeparator(Separator.PERIOD)
-        assertEquals(",", formatter.fractional)
-        assertEquals("123E+21", formatter.format(ENG_VALUE))
-        assertEquals("123,3E+21", formatter.format(ENG_VALUE_FRACTIONAL))
-        assertEquals("123.456,789", formatter.format(COMPLETE_VALUE))
-        assertEquals("123.456,", formatter.format(INCOMPLETE_VALUE))
-        assertEquals("123.456", formatter.format(NO_FRACTIONAL_VALUE))
-        assertEquals("50+123.456÷8×0,8–12+", formatter.format(INCOMPLETE_EXPR))
-        assertEquals("50+123.456÷8×0,8–12+0–√9×4^9+2×(9+8×7)", formatter.format(COMPLETE_EXPR))
-        assertEquals("50+123.456÷89.078,,9×0,8–12+0–√9×4^9+2×(9+8×7)×sin(13sin123cos", formatter.format(LONG_HALF_COMPLETE_EXPR))
-        assertEquals("((((((((", formatter.format(SOME_BRACKETS))
+        fun String.format(): String = formatExpression(FormatterSymbols.Period)
+        assertEquals("123E+21", ENG_VALUE.format())
+        assertEquals("123,3E+21", ENG_VALUE_FRACTIONAL.format())
+        assertEquals("123.456,789", COMPLETE_VALUE.format())
+        assertEquals("123.456,", INCOMPLETE_VALUE.format())
+        assertEquals("123.456", NO_FRACTIONAL_VALUE.format())
+        assertEquals("50+123.456÷8×0,8−12+", INCOMPLETE_EXPR.format())
+        assertEquals("50+123.456÷8×0,8−12+0−√9×4^9+2×(9+8×7)", COMPLETE_EXPR.format())
+        assertEquals("50+123.456÷89.078,,9×0,8−12+0−√9×4^9+2×(9+8×7)×sin(13sin123cos", LONG_HALF_COMPLETE_EXPR.format())
+        assertEquals("((((((((", SOME_BRACKETS.format())
     }
 
     @Test
     fun formatTimeTest() {
-        formatter.setSeparator(Separator.SPACES)
+        val formatterSymbols = FormatterSymbols.Spaces
         var basicValue = BigDecimal.valueOf(1)
         val mContext: Context = RuntimeEnvironment.getApplication().applicationContext
-        assertEquals("-28", formatter.formatTime(mContext, "-28", basicValue))
-        assertEquals("-0.05", formatter.formatTime(mContext, "-0.05", basicValue))
-        assertEquals("0", formatter.formatTime(mContext, "0", basicValue))
-        assertEquals("0", formatter.formatTime(mContext, "-0", basicValue))
+
+        fun String.formatTime() = this.formatTime(mContext, basicValue, formatterSymbols)
+
+        assertEquals("−28", "-28".formatTime())
+        assertEquals("−0.05", "-0.05".formatTime())
+        assertEquals("0", "0".formatTime())
+        assertEquals("0", "−0".formatTime())
 
         basicValue = BigDecimal.valueOf(86_400_000_000_000_000_000_000.0)
-        assertEquals("-28d", formatter.formatTime(mContext, "-28", basicValue))
-        assertEquals("-1h 12m", formatter.formatTime(mContext, "-0.05", basicValue))
-        assertEquals("0", formatter.formatTime(mContext, "0", basicValue))
-        assertEquals("0", formatter.formatTime(mContext, "-0", basicValue))
+        assertEquals("−28d", "-28".formatTime())
+        assertEquals("−1h 12m", "-0.05".formatTime())
+        assertEquals("0", "0".formatTime())
+        assertEquals("0", "-0".formatTime())
 
         // DAYS
         basicValue = BigDecimal.valueOf(86_400_000_000_000_000_000_000.0)
-        assertEquals("12h", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("1h 12m", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("7m 12s", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28d", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("90d", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("90d 12h", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("90d 7m 12s", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("12h","0.5".formatTime())
+        assertEquals("1h 12m","0.05".formatTime())
+        assertEquals("7m 12s","0.005".formatTime())
+        assertEquals("28d","28".formatTime())
+        assertEquals("90d","90".formatTime())
+        assertEquals("90d 12h","90.5".formatTime())
+        assertEquals("90d 7m 12s","90.005".formatTime())
 
         // HOURS
         basicValue = BigDecimal.valueOf(3_600_000_000_000_000_000_000.0)
-        assertEquals("30m", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("3m", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("18s", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("1d 4h", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("3d 18h", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("3d 18h 30m", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("3d 18h 18s", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("30m", "0.5".formatTime())
+        assertEquals("3m", "0.05".formatTime())
+        assertEquals("18s", "0.005".formatTime())
+        assertEquals("1d 4h", "28".formatTime())
+        assertEquals("3d 18h", "90".formatTime())
+        assertEquals("3d 18h 30m", "90.5".formatTime())
+        assertEquals("3d 18h 18s", "90.005".formatTime())
 
         // MINUTES
         basicValue = BigDecimal.valueOf(60_000_000_000_000_000_000.0)
-        assertEquals("30s", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("3s", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("300ms", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28m", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("1h 30m", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("1h 30m 30s", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("1h 30m 300ms", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("30s", "0.5".formatTime())
+        assertEquals("3s", "0.05".formatTime())
+        assertEquals("300ms", "0.005".formatTime())
+        assertEquals("28m", "28".formatTime())
+        assertEquals("1h 30m", "90".formatTime())
+        assertEquals("1h 30m 30s", "90.5".formatTime())
+        assertEquals("1h 30m 300ms", "90.005".formatTime())
 
         // SECONDS
         basicValue = BigDecimal.valueOf(1_000_000_000_000_000_000)
-        assertEquals("500ms", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("50ms", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("5ms", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28s", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("1m 30s", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("1m 30s 500ms", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("1m 30s 5ms", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("500ms", "0.5".formatTime())
+        assertEquals("50ms", "0.05".formatTime())
+        assertEquals("5ms", "0.005".formatTime())
+        assertEquals("28s", "28".formatTime())
+        assertEquals("1m 30s", "90".formatTime())
+        assertEquals("1m 30s 500ms", "90.5".formatTime())
+        assertEquals("1m 30s 5ms", "90.005".formatTime())
 
         // MILLISECONDS
         basicValue = BigDecimal.valueOf(1_000_000_000_000_000)
-        assertEquals("500µs", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("50µs", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("5µs", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28ms", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("90ms", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("90ms 500µs", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("90ms 5µs", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("500µs", "0.5".formatTime())
+        assertEquals("50µs", "0.05".formatTime())
+        assertEquals("5µs", "0.005".formatTime())
+        assertEquals("28ms", "28".formatTime())
+        assertEquals("90ms", "90".formatTime())
+        assertEquals("90ms 500µs", "90.5".formatTime())
+        assertEquals("90ms 5µs", "90.005".formatTime())
 
         // MICROSECONDS
         basicValue = BigDecimal.valueOf(1_000_000_000_000)
-        assertEquals("500ns", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("50ns", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("5ns", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28µs", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("90µs", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("90µs 500ns", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("90µs 5ns", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("500ns", "0.5".formatTime())
+        assertEquals("50ns", "0.05".formatTime())
+        assertEquals("5ns", "0.005".formatTime())
+        assertEquals("28µs", "28".formatTime())
+        assertEquals("90µs", "90".formatTime())
+        assertEquals("90µs 500ns", "90.5".formatTime())
+        assertEquals("90µs 5ns", "90.005".formatTime())
 
         // NANOSECONDS
         basicValue = BigDecimal.valueOf(1_000_000_000)
-        assertEquals("500 000 000as", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("50 000 000as", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("5 000 000as", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28ns", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("90ns", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("90ns 500 000 000as", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("90ns 5 000 000as", formatter.formatTime(mContext, "90.005", basicValue))
+        assertEquals("500 000 000as", "0.5".formatTime())
+        assertEquals("50 000 000as", "0.05".formatTime())
+        assertEquals("5 000 000as", "0.005".formatTime())
+        assertEquals("28ns", "28".formatTime())
+        assertEquals("90ns", "90".formatTime())
+        assertEquals("90ns 500 000 000as", "90.5".formatTime())
+        assertEquals("90ns 5 000 000as", "90.005".formatTime())
 
         // ATTOSECONDS
         basicValue = BigDecimal.valueOf(1)
-        assertEquals("0.5", formatter.formatTime(mContext, "0.5", basicValue))
-        assertEquals("0.05", formatter.formatTime(mContext, "0.05", basicValue))
-        assertEquals("0.005", formatter.formatTime(mContext, "0.005", basicValue))
-        assertEquals("28", formatter.formatTime(mContext, "28", basicValue))
-        assertEquals("90", formatter.formatTime(mContext, "90", basicValue))
-        assertEquals("90.5", formatter.formatTime(mContext, "90.5", basicValue))
-        assertEquals("90.005", formatter.formatTime(mContext, "90.005", basicValue))
-    }
-
-    @Test
-    fun fromSeparatorToSpacesTest() {
-        formatter.setSeparator(Separator.SPACES)
-        assertEquals("123 456.789", formatter.fromSeparator("123,456.789", Separator.COMMA))
-        assertEquals("123 456.789", formatter.fromSeparator("123 456.789", Separator.SPACES))
-        assertEquals("123 456.789", formatter.fromSeparator("123.456,789", Separator.PERIOD))
-    }
-
-    @Test
-    fun fromSeparatorToPeriodTest() {
-        formatter.setSeparator(Separator.PERIOD)
-        assertEquals("123.456,789", formatter.fromSeparator("123,456.789", Separator.COMMA))
-        assertEquals("123.456,789", formatter.fromSeparator("123 456.789", Separator.SPACES))
-        assertEquals("123.456,789", formatter.fromSeparator("123.456,789", Separator.PERIOD))
-    }
-
-    @Test
-    fun fromSeparatorToCommaTest() {
-        formatter.setSeparator(Separator.COMMA)
-        assertEquals("123,456.789", formatter.fromSeparator("123,456.789", Separator.COMMA))
-        assertEquals("123,456.789", formatter.fromSeparator("123 456.789", Separator.SPACES))
-        assertEquals("123,456.789", formatter.fromSeparator("123.456,789", Separator.PERIOD))
+        assertEquals("0.5", "0.5".formatTime())
+        assertEquals("0.05", "0.05".formatTime())
+        assertEquals("0.005", "0.005".formatTime())
+        assertEquals("28", "28".formatTime())
+        assertEquals("90", "90".formatTime())
+        assertEquals("90.5", "90.5".formatTime())
+        assertEquals("90.005", "90.005".formatTime())
     }
 }

data/calculator/src/main/java/com/sadellie/unitto/data/calculator/CalculatorRepository.kt

@@ -59,6 +59,7 @@ class CalculatorHistoryRepository @Inject constructor(
     private fun List<CalculatorHistoryEntity>.toHistoryItemList(): List<HistoryItem> {
         return this.map {
             HistoryItem(
+                id = it.entityId,
                 date = Date(it.timestamp),
                 expression = it.expression,
                 result = it.result

data/common/build.gradle.kts

@@ -26,4 +26,5 @@ android {
 
 dependencies {
     implementation(project(mapOf("path" to ":core:base")))
+    testImplementation(libs.junit)
 }

data/common/src/main/java/com/sadellie/unitto/data/common/BigDecimalUtils.kt

@@ -64,11 +64,7 @@ fun BigDecimal.setMinimumRequiredScale(prefScale: Int): BigDecimal {
 
 /**
  * Removes all trailing zeroes.
- *
- * @throws NumberFormatException if value is bigger than [Double.MAX_VALUE] to avoid memory overflow.
  */
 fun BigDecimal.trimZeros(): BigDecimal {
-    if (this.abs() > BigDecimal.valueOf(Double.MAX_VALUE)) throw NumberFormatException()
-
     return if (this.compareTo(BigDecimal.ZERO) == 0) BigDecimal.ZERO else this.stripTrailingZeros()
 }

data/common/src/main/java/com/sadellie/unitto/data/common/StringUtils.kt

@@ -18,6 +18,8 @@
 
 package com.sadellie.unitto.data.common
 
+import com.sadellie.unitto.core.base.Token
+
 /**
  * Compute Levenshtein Distance between this string and [secondString]. Doesn't matter which string is
  * first.
@@ -58,3 +60,18 @@ fun String.lev(secondString: String): Int {
 
     return cost[this.length]
 }
+
+fun String.isExpression(): Boolean {
+
+    if (isEmpty()) return false
+
+    // Positive numbers and zero
+    if (all { it.toString() in Token.Digit.allWithDot }) return false
+
+    // Negative numbers
+    // Needs to start with an negative
+    if (this.first().toString() != Token.Operator.minus) return true
+
+    // Rest of the string must be just like positive
+    return this.drop(1).isExpression()
+}

data/common/src/test/java/com/sadellie/unitto/data/common/IsExpressionText.kt

@@ -0,0 +1,49 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.data.common
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+
+class IsExpressionText {
+    @Test
+    fun `empty string`() = assertEquals(false, "".isExpression())
+
+    @Test
+    fun `positive real number`() = assertEquals(false, "123".isExpression())
+
+    @Test
+    fun `positive float`() = assertEquals(false, "123.123".isExpression())
+
+    @Test
+    fun `negative real`() = assertEquals(false, "−123".isExpression())
+
+    @Test
+    fun `negative float`() = assertEquals(false, "−123.123".isExpression())
+
+    @Test
+    fun `super negative float`() = assertEquals(false, "−−123.123".isExpression())
+
+    @Test
+    fun expression1() = assertEquals(true, "123.123+456".isExpression())
+
+    @Test
+    fun expression2() = assertEquals(true, "−123.123+456".isExpression())
+}

data/epoch/src/test/java/com/sadellie/unitto/data/epoch/DateToEpochTest.kt

@@ -18,8 +18,8 @@
 
 package com.sadellie.unitto.data.epoch
 
-import org.junit.Assert.assertEquals
-import org.junit.Test
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
 
 class DateToEpochTest {
 

data/evaluatto/build.gradle.kts

@@ -18,17 +18,14 @@
 
 plugins {
     id("unitto.library")
-    id("unitto.android.hilt")
 }
 
 android {
-    namespace = "com.sadellie.unitto.data.unitgroups"
+    // Different namespace. Possible promotion to a separate project.
+    namespace = "io.github.sadellie.evaluatto"
 }
 
 dependencies {
-    testImplementation(libs.junit)
-    implementation(libs.org.burnoutcrew.composereorderable)
-
     implementation(project(mapOf("path" to ":core:base")))
-    implementation(project(mapOf("path" to ":data:model")))
+    testImplementation(libs.junit)
 }

data/evaluatto/src/main/java/io/github/sadellie/evaluatto/Expression.kt

@@ -0,0 +1,309 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import com.sadellie.unitto.core.base.MAX_PRECISION
+import com.sadellie.unitto.core.base.Token
+import java.math.BigDecimal
+import java.math.MathContext
+import java.math.RoundingMode
+import kotlin.math.cos
+import kotlin.math.sin
+import kotlin.math.tan
+import kotlin.math.acos
+import kotlin.math.asin
+import kotlin.math.atan
+import kotlin.math.ln
+import kotlin.math.log
+import kotlin.math.exp
+import kotlin.math.pow
+
+sealed class ExpressionException(override val message: String): Exception(message) {
+    class DivideByZero : ExpressionException("Can't divide by zero")
+    class FactorialCalculation : ExpressionException("Can calculate factorial of non-negative real numbers only")
+    class BadExpression : ExpressionException("Invalid expression. Probably some operator lacks argument")
+    class TooBig : ExpressionException("Value is too big")
+}
+
+class Expression(input: String, private val radianMode: Boolean = true) {
+    private val tokens = Tokenizer(input).tokenize()
+    private var cursorPosition = 0
+
+    /**
+     * Expression := [ "-" ] Term { ("+" | "-") Term }
+     *
+     * Term       := Factor { ( "*" | "/" ) Factor }
+     *
+     * Factor     := RealNumber | "(" Expression ")"
+     *
+     * RealNumber := Digit{Digit} | [ Digit ] "." {Digit}
+     *
+     * Digit      := "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
+     */
+    fun calculate(): BigDecimal {
+        try {
+            return parseExpression()
+        } catch (e: UninitializedPropertyAccessException) {
+            throw ExpressionException.BadExpression()
+        }
+    }
+
+    // Null when at the end of expression
+    private fun peek() = tokens.getOrNull(cursorPosition) ?: ""
+
+    private fun moveIfMatched(token: String): Boolean {
+        if (peek() == token) {
+            // Move cursor
+            cursorPosition++
+            return true
+        }
+        return false
+    }
+
+    // Expression := [ "-" ] Term { ("+" | "-") Term }
+    private fun parseExpression(): BigDecimal {
+        var expression = parseTerm()
+
+        while (peek() in listOf(Token.Operator.plus, Token.Operator.minus)) {
+            when {
+                moveIfMatched(Token.Operator.plus) -> expression += parseTerm()
+                moveIfMatched(Token.Operator.minus) -> expression -= parseTerm()
+            }
+        }
+        return expression
+    }
+
+    // Term       := Factor { ( "*" | "/" ) Factor }
+    private fun parseTerm(): BigDecimal {
+        var expression = parseFactor()
+
+        while (peek() in listOf(Token.Operator.multiply, Token.Operator.divide)) {
+            when {
+                moveIfMatched(Token.Operator.multiply) -> expression =
+                    expression.multiply(parseFactor())
+
+                moveIfMatched(Token.Operator.divide) -> {
+                    val divisor = parseFactor()
+                    if (divisor.compareTo(BigDecimal.ZERO) == 0) throw ExpressionException.DivideByZero()
+
+                    expression = expression.divide(divisor, RoundingMode.HALF_EVEN)
+                }
+            }
+        }
+        return expression
+    }
+
+    // Factor     := RealNumber | "(" Expression ")"
+    private fun parseFactor(negative: Boolean = false): BigDecimal {
+        // This will throw Exception if some function lacks argument, for example: "cos()" or "600^"
+        lateinit var expr: BigDecimal
+
+        fun parseFuncParentheses(): BigDecimal {
+            return if (moveIfMatched(Token.Operator.leftBracket)) {
+                // Parse in parentheses
+                val res = parseExpression()
+
+                // Check if parentheses is closed
+                if (!moveIfMatched(Token.Operator.rightBracket)) throw Exception("Closing bracket is missing")
+                res
+            } else {
+                parseFactor()
+            }
+        }
+
+        // Unary plus
+        if (moveIfMatched(Token.Operator.plus)) return parseFactor()
+
+        // Unary minus
+        if (moveIfMatched(Token.Operator.minus)) {
+            return -parseFactor(true)
+        }
+
+        // Parentheses
+        if (moveIfMatched(Token.Operator.leftBracket)) {
+            // Parse in parentheses
+            expr = parseExpression()
+
+            // Check if parentheses is closed
+            if (!moveIfMatched(Token.Operator.rightBracket)) throw Exception("Closing bracket is missing")
+        }
+
+        // Numbers
+        val possibleNumber = peek()
+        // We know that if next token starts with a digit or dot, it can be converted into BigDecimal
+        // Ugly
+        if (possibleNumber.isNotEmpty()) {
+            if (Token.Digit.allWithDot.contains(possibleNumber.first().toString())) {
+                expr = BigDecimal(possibleNumber).setScale(MAX_PRECISION)
+                cursorPosition++
+            }
+        }
+
+        // PI
+        if (moveIfMatched(Token.Const.pi)) {
+            expr = BigDecimal.valueOf(Math.PI)
+        }
+
+        // e
+        if (moveIfMatched(Token.Const.e)) {
+            expr = BigDecimal.valueOf(Math.E)
+        }
+
+        // sqrt
+        if (moveIfMatched(Token.Operator.sqrt)) {
+            expr = parseFuncParentheses().pow(BigDecimal(0.5))
+        }
+
+        // sin
+        if (moveIfMatched(Token.Func.sin)) {
+            expr = parseFuncParentheses().sin(radianMode)
+        }
+
+        // cos
+        if (moveIfMatched(Token.Func.cos)) {
+            expr = parseFuncParentheses().cos(radianMode)
+        }
+
+        // tan
+        if (moveIfMatched(Token.Func.tan)) {
+            expr = parseFuncParentheses().tan(radianMode)
+        }
+
+        // arsin
+        if (moveIfMatched(Token.Func.arsin)) {
+            expr = parseFuncParentheses().arsin(radianMode)
+        }
+
+        // arcos
+        if (moveIfMatched(Token.Func.arcos)) {
+            expr = parseFuncParentheses().arcos(radianMode)
+        }
+
+        // actan
+        if (moveIfMatched(Token.Func.actan)) {
+            expr = parseFuncParentheses().artan(radianMode)
+        }
+
+        // ln
+        if (moveIfMatched(Token.Func.ln)) {
+            expr = parseFuncParentheses().ln()
+        }
+
+        // log
+        if (moveIfMatched(Token.Func.log)) {
+            expr = parseFuncParentheses().log()
+        }
+
+        // exp
+        if (moveIfMatched(Token.Func.exp)) {
+            expr = parseFuncParentheses().exp()
+        }
+
+        // Power
+        if (moveIfMatched(Token.Operator.power)) {
+            expr = expr.pow(parseFactor())
+        }
+
+        // Modulo
+        if (moveIfMatched(Token.Operator.modulo)) {
+            expr = expr.remainder(parseFactor())
+        }
+
+        // Factorial
+        if (moveIfMatched(Token.Operator.factorial)) {
+            if (negative) throw ExpressionException.FactorialCalculation()
+            expr = expr.factorial()
+        }
+
+        return expr
+    }
+}
+
+private fun BigDecimal.sin(radianMode: Boolean): BigDecimal {
+    val angle: Double = if (radianMode) this.toDouble() else Math.toRadians(this.toDouble())
+    return sin(angle).toBigDecimal()
+}
+
+private fun BigDecimal.arsin(radianMode: Boolean): BigDecimal {
+    val angle: Double = asin(this.toDouble())
+    return (if (radianMode) angle else Math.toDegrees(angle)).toBigDecimal()
+}
+
+private fun BigDecimal.cos(radianMode: Boolean): BigDecimal {
+    val angle: Double = if (radianMode) this.toDouble() else Math.toRadians(this.toDouble())
+    return cos(angle).toBigDecimal()
+}
+
+private fun BigDecimal.arcos(radianMode: Boolean): BigDecimal {
+    val angle: Double = acos(this.toDouble())
+    return (if (radianMode) angle else Math.toDegrees(angle)).toBigDecimal()
+}
+
+private fun BigDecimal.tan(radianMode: Boolean): BigDecimal {
+    val angle: Double = if (radianMode) this.toDouble() else Math.toRadians(this.toDouble())
+    return tan(angle).toBigDecimal()
+}
+
+private fun BigDecimal.artan(radianMode: Boolean): BigDecimal {
+    val angle: Double = atan(this.toDouble())
+    return (if (radianMode) angle else Math.toDegrees(angle)).toBigDecimal()
+}
+
+private fun BigDecimal.ln(): BigDecimal {
+    return ln(this.toDouble()).toBigDecimal()
+}
+
+private fun BigDecimal.log(): BigDecimal {
+    return log(this.toDouble(), 10.0).toBigDecimal()
+}
+
+private fun BigDecimal.exp(): BigDecimal {
+    return exp(this.toDouble()).toBigDecimal()
+}
+
+private fun BigDecimal.pow(n: BigDecimal): BigDecimal {
+    val mathContext: MathContext = MathContext.DECIMAL64
+
+    var right = n
+    val signOfRight = right.signum()
+    right = right.multiply(signOfRight.toBigDecimal())
+    val remainderOfRight = right.remainder(BigDecimal.ONE)
+    val n2IntPart = right.subtract(remainderOfRight)
+    val intPow = pow(n2IntPart.intValueExact(), mathContext)
+    val doublePow = BigDecimal(
+        toDouble().pow(remainderOfRight.toDouble())
+    )
+
+    var result = intPow.multiply(doublePow, mathContext)
+    if (signOfRight == -1) result =
+        BigDecimal.ONE.divide(result, mathContext.precision, RoundingMode.HALF_UP)
+
+    return result
+}
+
+private fun BigDecimal.factorial(): BigDecimal {
+    if (this.remainder(BigDecimal.ONE).compareTo(BigDecimal.ZERO) != 0) throw ExpressionException.FactorialCalculation()
+    if (this < BigDecimal.ZERO) throw ExpressionException.FactorialCalculation()
+
+    var expr = this
+    for (i in 1 until this.toInt()) {
+        expr *= BigDecimal(i)
+    }
+    return expr
+}

data/evaluatto/src/main/java/io/github/sadellie/evaluatto/Tokenizer.kt

@@ -0,0 +1,244 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import com.sadellie.unitto.core.base.Token
+
+sealed class TokenizerException(override val message: String) : Exception(message) {
+    class BadNumber : TokenizerException("Number has multiple commas in it")
+}
+
+class Tokenizer(private val streamOfTokens: String) {
+    // Don't create object at all?
+    fun tokenize(): List<String> {
+        var cursor = 0
+        val tokens: MutableList<String> = mutableListOf()
+
+        while (cursor != streamOfTokens.length) {
+            val nextToken = peekTokenAfter(cursor)
+
+            if (nextToken != null) {
+                tokens.add(nextToken)
+                cursor += nextToken.length
+            } else {
+                // Didn't find any token, move left slowly (by 1 symbol)
+                cursor++
+            }
+        }
+
+        return tokens.repairLexicon()
+    }
+
+    private fun peekTokenAfter(cursor: Int): String? {
+        Token.expressionTokens.forEach { token ->
+            val subs = streamOfTokens
+                .substring(
+                    cursor,
+                    (cursor + token.length).coerceAtMost(streamOfTokens.length)
+                )
+            if (subs == token) {
+                // Got a digit, see if there are other digits coming after
+                if (token in Token.Digit.allWithDot) {
+                    val number = streamOfTokens
+                        .substring(cursor)
+                        .takeWhile { Token.Digit.allWithDot.contains(it.toString()) }
+
+                    if (number.count { it.toString() == Token.Digit.dot } > 1) {
+                        throw TokenizerException.BadNumber()
+                    }
+
+                    return number
+                }
+                return token
+            }
+        }
+        return null
+    }
+
+    private fun List<String>.repairLexicon(): List<String> {
+        return this
+            .missingClosingBrackets()
+            .missingMultiply()
+            .unpackAlPercents()
+            // input like 80%80% should be treated as 80%-80%.
+            // After unpacking we get (80/100)(80/100), the multiply is missing
+            // No, we can't unpack before fixing missing multiply.
+            // Ideally we we need to add missing multiply for 80%80%
+            // In that case unpackAlPercents gets input with all operators 80%*80% in this case
+            // Can't be done right now since missingMultiply checks for tokens in front only
+            .missingMultiply()
+    }
+
+    private fun List<String>.missingClosingBrackets(): List<String> {
+        val leftBracket = this.count { it == Token.Operator.leftBracket }
+        val rightBrackets = this.count { it == Token.Operator.rightBracket }
+        val neededBrackets = leftBracket - rightBrackets
+
+        if (neededBrackets <= 0) return this
+
+        var fixed = this
+        repeat(neededBrackets) {
+            fixed = fixed + Token.Operator.rightBracket
+        }
+        return fixed
+    }
+
+    private fun List<String>.missingMultiply(): List<String> {
+        val results = this.toMutableList()
+        val insertIndexes = mutableListOf<Int>()
+
+        // Records the index if it needs a multiply symbol
+        fun needsMultiply(index: Int) {
+            val tokenInFront = results.getOrNull(index - 1) ?: return
+
+            when {
+                tokenInFront.first().toString() in Token.Digit.allWithDot ||
+                tokenInFront == Token.Operator.rightBracket ||
+                tokenInFront in Token.Const.all -> {
+                    // Can't add token now, it will modify tokens list (we are looping over it)
+                    insertIndexes.add(index + insertIndexes.size)
+                }
+            }
+        }
+
+        results.forEachIndexed { index, s ->
+            when (s) {
+                Token.Operator.leftBracket,
+                Token.Operator.sqrt,
+                in Token.Const.all,
+                in Token.Func.all -> needsMultiply(index)
+            }
+        }
+
+        insertIndexes.forEach {
+            results.add(it, Token.Operator.multiply)
+        }
+
+        return results
+    }
+
+    private fun List<String>.unpackAlPercents(): List<String> {
+        var result = this
+        while (result.contains(Token.Operator.percent)) {
+            val percIndex = result.indexOf(Token.Operator.percent)
+            result = result.unpackPercentAt(percIndex)
+        }
+        return result
+    }
+
+    private fun List<String>.unpackPercentAt(percentIndex: Int): List<String> {
+        var cursor = percentIndex
+
+        // get whatever is the percentage
+        val percentage = this.getNumberOrExpressionBefore(percentIndex)
+        // Move cursor
+        cursor -= percentage.size
+
+        // get the operator in front
+        cursor -= 1
+        val operator = this.getOrNull(cursor)
+
+        // Don't go further
+        if ((operator == null) or (operator !in listOf(Token.Operator.plus, Token.Operator.minus))) {
+            val mutList = this.toMutableList()
+
+            // Remove percentage
+            mutList.removeAt(percentIndex)
+
+            //Add opening bracket before percentage
+            mutList.add(percentIndex - percentage.size, Token.Operator.leftBracket)
+
+            // Add "/ 100" and closing bracket
+            mutList.addAll(percentIndex + 1, listOf(Token.Operator.divide, "100", Token.Operator.rightBracket))
+
+            return mutList
+        }
+        // Get the base
+        val base = this.getBaseBefore(cursor)
+        val mutList = this.toMutableList()
+
+        // Remove percentage
+        mutList.removeAt(percentIndex)
+
+        //Add opening bracket before percentage
+        mutList.add(percentIndex - percentage.size, Token.Operator.leftBracket)
+
+        // Add "/ 100" and other stuff
+        mutList.addAll(
+            percentIndex + 1,
+            listOf(
+                Token.Operator.divide,
+                "100",
+                Token.Operator.multiply,
+                Token.Operator.leftBracket,
+                *base.toTypedArray(),
+                Token.Operator.rightBracket,
+                Token.Operator.rightBracket
+            )
+        )
+
+        return mutList
+    }
+
+    private fun List<String>.getNumberOrExpressionBefore(pos: Int): List<String> {
+        val digits = Token.Digit.allWithDot.map { it[0] }
+
+        val tokenInFront = this[pos - 1]
+
+        // Just number
+        if (tokenInFront.all { it in digits }) return listOf(tokenInFront)
+
+        // Not just a number. Probably expression in brackets.
+        if (tokenInFront != Token.Operator.rightBracket) throw Exception("Unexpected token before percentage")
+
+        // Start walking left until we get balanced brackets
+        var cursor = pos - 1
+        var leftBrackets = 0
+        var rightBrackets = 1 // We set 1 because we start with closing bracket
+
+        while (leftBrackets != rightBrackets) {
+            cursor--
+            val currentToken = this[cursor]
+            if (currentToken == Token.Operator.leftBracket) leftBrackets++
+            if (currentToken == Token.Operator.rightBracket) rightBrackets++
+        }
+
+        return this.subList(cursor, pos)
+    }
+
+    private fun List<String>.getBaseBefore(pos: Int): List<String> {
+        var cursor = pos
+        var leftBrackets = 0
+        var rightBrackets = 0
+
+        while ((--cursor >= 0)) {
+            val currentToken = this[cursor]
+
+            if (currentToken == Token.Operator.leftBracket) leftBrackets++
+            if (currentToken == Token.Operator.rightBracket) rightBrackets++
+
+            if (leftBrackets > rightBrackets) break
+        }
+
+        // Return cursor back to last token
+        cursor += 1
+
+        return this.subList(cursor, pos)
+    }
+}

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/ExpressionComplexTest.kt

@@ -0,0 +1,60 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Test
+
+class ExpressionComplexTest {
+
+    @Test
+    fun expression1() = assertExpr("94×π×89×cos(0.5)−3!÷9^(2)×√8", "23064.9104578494")
+
+    @Test
+    fun expression2() = assertExpr("√(25)×2+10÷2", "15")
+
+    @Test
+    fun expression3() = assertExpr("(3+4)×(5−2)", "21")
+
+    @Test
+    fun expression4() = assertExpr("8÷4+2×3", "8")
+
+    @Test
+    fun expression5() = assertExpr("2^3+4^2−5×6", "-6")
+
+    @Test
+    fun expression6() = assertExpr("(10−2)^2÷8+3×2", "14")
+
+    @Test
+    fun expression7() = assertExpr("7!÷3!−5!÷2!", "780")
+
+    @Test
+    fun expression8() = assertExpr("(2^2+3^3)÷5−√(16)×2", "-1.8")
+
+    @Test
+    fun expression9() = assertExpr("10×log(100)+2^4−3^2", "27")
+
+    @Test
+    fun expression10() = assertExpr("sin(π÷3)×cos(π÷6)+tan(π÷4)−√3", "0.017949192431123")
+
+    @Test
+    fun expression11() = assertExpr("2^6−2^5+2^4−2^3+2^−2^1+2^0", "41.25")
+
+    @Test
+    fun expression12() = assertExpr("2×(3+4)×(5−2)÷6", "7")
+}

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/ExpressionExceptionsTest.kt

@@ -0,0 +1,42 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Test
+
+class ExpressionExceptionsTest {
+
+    @Test
+    fun `divide by zero`() = assertExprFail(ExpressionException.DivideByZero::class.java, "2÷0")
+
+    @Test
+    fun `factorial of float`() = assertExprFail(ExpressionException.FactorialCalculation::class.java, "3.2!")
+
+    @Test
+    fun `factorial of negative`() = assertExprFail(ExpressionException.FactorialCalculation::class.java, "−5!")
+
+    @Test
+    fun `factorial of negative2`() = assertExprFail(ExpressionException.FactorialCalculation::class.java, "(−5)!")
+
+    @Test
+    fun `ugly ahh expression`() = assertExprFail(ExpressionException.BadExpression::class.java, "100+cos()")
+
+    @Test
+    fun `ugly ahh expression2`() = assertExprFail(TokenizerException.BadNumber::class.java, "...")
+}

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/ExpressionSimpleTest.kt

@@ -0,0 +1,111 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Test
+
+class ExpressionSimpleTest {
+
+    @Test
+    fun expression1() = assertExpr("789", "789")
+
+    @Test
+    fun expression2() = assertExpr("0.1+0.2", "0.3")
+
+    @Test
+    fun expression3() = assertExpr(".1+.2", "0.3")
+
+    @Test
+    fun expression4() = assertExpr("789+200", "989")
+
+    @Test
+    fun expression5() = assertExpr("600×7.89", "4734")
+
+    @Test
+    fun expression6() = assertExpr("600÷7", "85.7142857143")
+
+    @Test
+    fun expression7() = assertExpr("(200+200)×200", "80000")
+
+    @Test
+    fun expression8() = assertExpr("99^5", "9509900499")
+
+    @Test
+    fun expression9() = assertExpr("12!", "479001600")
+
+    @Test
+    fun expression10() = assertExpr("12#5", "2")
+
+    @Test
+    fun `125 plus 9 percent`() = assertExpr("125+9%", "136.25")
+
+    @Test
+    fun expression11() = assertExpr("12×√5", "26.8328157300")
+
+    @Test
+    fun expression12() = assertExpr("sin(42)", "-0.9165215479")
+
+    @Test
+    fun expression13() = assertExpr("sin(42)", "0.6691306064", radianMode = false)
+
+    @Test
+    fun expression14() = assertExpr("cos(42)", "-0.3999853150")
+
+    @Test
+    fun expression15() = assertExpr("cos(42)", "0.7431448255", radianMode = false)
+
+    @Test
+    fun expression16() = assertExpr("tan(42)", "2.2913879924")
+
+    @Test
+    fun expression17() = assertExpr("tan(42)", "0.9004040443", radianMode = false)
+
+    @Test
+    fun expression18() = assertExpr("sin⁻¹(.69)", "0.7614890527")
+
+    @Test
+    fun expression19() = assertExpr("sin⁻¹(.69)", "43.6301088679", radianMode = false)
+
+    @Test
+    fun expression20() = assertExpr("cos⁻¹(.69)", "0.8093072740")
+
+    @Test
+    fun expression21() = assertExpr("cos⁻¹(.69)", "46.3698911321", radianMode = false)
+
+    @Test
+    fun expression22() = assertExpr("tan⁻¹(.69)", "0.6039829783")
+
+    @Test
+    fun expression23() = assertExpr("tan⁻¹(.69)", "34.6056755516", radianMode = false)
+
+    @Test
+    fun expression24() = assertExpr("ln(.69)", "-0.3710636814")
+
+    @Test
+    fun expression25() = assertExpr("log(.69)", "-0.1611509093")
+
+    @Test
+    fun expression26() = assertExpr("exp(3)", "20.0855369232")
+
+    @Test
+    fun expression27() = assertExpr("π", "3.1415926536")
+
+    @Test
+    fun expression28() = assertExpr("e", "2.7182818285")
+}

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/FixLexiconTest.kt

@@ -0,0 +1,129 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Test
+
+class FixLexiconTest {
+
+    @Test
+    fun `missing multiply`() {
+        assertLex(
+            "2×(69−420)", "2(69−420)"
+        )
+
+        assertLex(
+            "0.×(69−420)", "0.(69−420)"
+        )
+
+        assertLex(
+            ".0×(69−420)", ".0(69−420)"
+        )
+
+        assertLex(
+            ".×(69−420)", ".(69−420)"
+        )
+
+        assertLex(
+            "2×(69−420)×(23−4)×cos(9)×tan((sin⁻¹(.9)))",
+            "2(69−420)(23−4)cos(9)tan((sin⁻¹(.9)))"
+        )
+
+        assertLex(
+            "e×e+π", "ee+π"
+        )
+    }
+
+    @Test
+    fun `balanced brackets`() {
+        assertLex(
+            "123×(12+4)", "123(12+4"
+        )
+
+        assertLex(
+            "12312+4", "12312+4"
+        )
+
+        assertLex(
+            "123)))12+4", "123)))12+4"
+        )
+
+        assertLex(
+            "sin(cos(tan(3)))", "sin(cos(tan(3"
+        )
+
+        assertLex(
+            "sin(cos(tan(3)))", "sin(cos(tan(3)"
+        )
+
+        assertLex(
+            "sin(cos(tan(3)))", "sin(cos(tan(3))"
+        )
+    }
+
+    @Test
+    fun `unpack percentage`() {
+        // 132.5+14% −> 132.5+132.5*0.14
+        assertLex(
+            "132.5+(14÷100×(132.5))", "132.5+14%"
+        )
+
+        // 132.5+(14)% −> 132.5+(14)/100*132.5
+        assertLex(
+            "132.5+((14)÷100×(132.5))" , "132.5+(14)%"
+        )
+
+        // 132.5+(15+4)% −> 132.5+(15+4)*132.5/100
+        assertLex(
+            "132.5+((15+4)÷100×(132.5))", "132.5+(15+4)%"
+        )
+
+        // (132.5+12%)+(15+4)% −> (132.5+12/100*132.5)+(15+4)/100*(132.5+12/100*132.5)
+        assertLex(
+            "(132.5+(12÷100×(132.5)))+((15+4)÷100×((132.5+(12÷100×(132.5)))))", "(132.5+12%)+(15+4)%"
+        )
+
+        // 2% −> 2/100
+        assertLex(
+            "(2÷100)", "2%"
+        )
+
+        assertLex(
+            "((2)÷100)", "(2)%"
+        )
+
+        assertLex(
+            "(132.5+5)+(90÷100×((132.5+5)))", "(132.5+5)+90%"
+        )
+
+        assertLex(
+            "((90÷100)+(90÷100×((90÷100))))", "(90%+90%)"
+        )
+
+        assertLex(
+            "((90÷100)÷(90÷100))+((90÷100)−(90÷100×((90÷100))))", "(90%÷90%)+(90%−90%)"
+        )
+
+        assertLex("(80÷100)×(80÷100)", "80%80%")
+
+        assertLex("10+(2.0÷100×(10))", "10+2.0%")
+
+        assertLex("10+(2.÷100×(10))", "10+2.%")
+    }
+}

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/Helpers.kt

@@ -0,0 +1,46 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertThrows
+import java.math.BigDecimal
+import java.math.RoundingMode
+
+fun assertExpr(expr: String, result: String, radianMode: Boolean = true) =
+    assertEquals(
+        BigDecimal(result).setScale(10, RoundingMode.HALF_EVEN),
+        Expression(expr, radianMode).calculate().setScale(10, RoundingMode.HALF_EVEN)
+    )
+
+fun <T : Throwable?> assertExprFail(
+    expectedThrowable: Class<T>?,
+    expr: String,
+    radianMode: Boolean = true
+) {
+    assertThrows(expectedThrowable) {
+        Expression(expr, radianMode = radianMode).calculate()
+    }
+}
+
+fun assertLex(expected: List<String>, actual: String) =
+    assertEquals(expected, Tokenizer(actual).tokenize())
+
+fun assertLex(expected: String, actual: String) =
+    assertEquals(expected, Tokenizer(actual).tokenize().joinToString(""))

data/evaluatto/src/test/java/io/github/sadellie/evaluatto/TokenizerTest.kt

@@ -0,0 +1,51 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package io.github.sadellie.evaluatto
+
+import org.junit.jupiter.api.Test
+
+class TokenizerTest {
+
+    @Test
+    fun tokens1() = assertLex(listOf("789"), "789")
+
+    @Test
+    fun tokens2() = assertLex(listOf("789", "+", "200"), "789+200")
+
+    @Test
+    fun tokens3() = assertLex(listOf("0.1", "+", "0.2"), "0.1+0.2")
+
+    @Test
+    fun tokens4() = assertLex(listOf(".1", "+", ".2"), ".1+.2")
+
+    @Test
+    fun tokens5() = assertLex(listOf(".1", "+", ".2"), ".1+.2")
+
+    @Test
+    fun tokens6() = assertLex(listOf("789", "+", "200", "+", "cos", "(", "456", ")"), "789+200+cos(456)")
+
+    @Test
+    fun tokens8() = assertLex(emptyList(), "")
+
+    @Test
+    fun tokens9() = assertLex(listOf("e"), "something") // Tokenizer knows "e"
+
+    @Test
+    fun tokens10() = assertLex(emptyList(), "funnyword")
+}

data/licenses/src/main/java/com/sadellie/unitto/data/licenses/Library.kt

@@ -28,23 +28,6 @@ data class AppLibrary(
 
 val ALL_LIBRARIES by lazy {
     listOf(
-        AppLibrary(
-            name = "MathParser.org-mXparser",
-            dev = "Mariusz Gromada",
-            website = "https://github.com/mariuszgromada/MathParser.org-mXparser/",
-            license = "Non-Commercial license",
-            description = "Math Parser Java Android C# .NET/MONO (.NET Framework, .NET Core, .NET " +
-                    "Standard, .NET PCL, Xamarin.Android, Xamarin.iOS) CLS Library - a super easy, rich" +
-                    " and flexible mathematical expression parser (expression evaluator, expression " +
-                    "provided as plain text / strings) for JAVA and C#."
-        ),
-        AppLibrary(
-            name = "ExprK",
-            dev = "Keelar",
-            website = "https://github.com/Keelar/ExprK",
-            license = "MIT license",
-            description = "A simple mathematical expression evaluator for Kotlin and Java, written in Kotlin."
-        ),
         AppLibrary(
             name = "currency-api",
             dev = "Fawaz Ahmed (fawazahmed0)",
@@ -122,20 +105,6 @@ val ALL_LIBRARIES by lazy {
             license = "Apache-2.0",
             description = "Utilities for Jetpack Compose"
         ),
-        AppLibrary(
-            name = "firebase-analytics-ktx",
-            dev = "Google",
-            website = "https://developer.android.com/studio/terms.html",
-            license = "ASDKL",
-            description = "Library to collect and send usage statistics"
-        ),
-        AppLibrary(
-            name = "firebase-crashlytics-ktx",
-            dev = "Google",
-            website = "https://developer.android.com/studio/terms.html",
-            license = "Apache-2.0",
-            description = "Library to collect and send crash logs"
-        ),
         AppLibrary(
             name = "Compose Tooling API",
             dev = "The Android Open Source Project",

data/model/src/main/java/com/sadellie/unitto/data/model/AbstractUnit.kt

@@ -37,7 +37,6 @@ import java.math.BigDecimal
  * @property renderedShortName Used as cache. Stores short name string for this specific device. Need for
  * search functionality.
  * @property isFavorite Whether this unit is favorite.
- * @property isEnabled Whether we need to show this unit or not
  * @property pairedUnit Latest paired unit on the right
  * @property counter The amount of time this unit was chosen
  */
@@ -50,7 +49,6 @@ abstract class AbstractUnit(
     var renderedName: String = String(),
     var renderedShortName: String = String(),
     var isFavorite: Boolean = false,
-    var isEnabled: Boolean = true,
     var pairedUnit: String? = null,
     var counter: Int = 0
 ) {

data/model/src/main/java/com/sadellie/unitto/data/model/DefaultUnit.kt

@@ -50,6 +50,9 @@ class DefaultUnit(
         value: BigDecimal,
         scale: Int
     ): BigDecimal {
+        // Avoid division by zero
+        if (unitTo.basicUnit.compareTo(BigDecimal.ZERO) == 0) return BigDecimal.ZERO
+
         return this
             .basicUnit
             .setScale(MAX_PRECISION)

data/model/src/main/java/com/sadellie/unitto/data/model/HistoryItem.kt

@@ -18,9 +18,10 @@
 
 package com.sadellie.unitto.data.model
 
-import java.util.*
+import java.util.Date
 
 data class HistoryItem(
+    val id: Int,
     val date: Date,
     val expression: String,
     val result: String

data/model/src/main/java/com/sadellie/unitto/data/model/UnitGroup.kt

@@ -19,6 +19,7 @@
 package com.sadellie.unitto.data.model
 
 import androidx.annotation.StringRes
+import com.sadellie.unitto.core.base.R
 
 val ALL_UNIT_GROUPS: List<UnitGroup> by lazy {
     UnitGroup.values().toList()

data/units/consumer-rules.pro

@@ -1,5 +1,15 @@
 -repackageclasses
 
+# https://github.com/square/retrofit/issues/3751#issuecomment-1192043644
+# Keep generic signature of Call, Response (R8 full mode strips signatures from non-kept items).
+ -keep,allowobfuscation,allowshrinking interface retrofit2.Call
+ -keep,allowobfuscation,allowshrinking class retrofit2.Response
+
+ # With R8 full mode generic signatures are stripped for classes that are not
+ # kept. Suspend functions are wrapped in continuations where the type argument
+ # is used.
+ -keep,allowobfuscation,allowshrinking class kotlin.coroutines.Continuation
+
 -keepclassmembers class ** {
     @com.squareup.moshi.FromJson *;
     @com.squareup.moshi.ToJson *;

data/units/src/main/java/com/sadellie/unitto/data/units/AllUnitsRepository.kt

@@ -48,6 +48,9 @@ import com.sadellie.unitto.data.units.collections.temperatureCollection
 import com.sadellie.unitto.data.units.collections.timeCollection
 import com.sadellie.unitto.data.units.collections.torqueCollection
 import com.sadellie.unitto.data.units.collections.volumeCollection
+import com.sadellie.unitto.data.units.remote.CurrencyApi
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 import java.math.BigDecimal
 import javax.inject.Inject
 import javax.inject.Singleton
@@ -123,8 +126,8 @@ class AllUnitsRepository @Inject constructor() {
     /**
      * Filter [AllUnitsRepository.allUnits] and group them.
      *
-     * @param hideBrokenCurrencies When set to True will remove [AbstractUnit]s that have
-     * [AbstractUnit.isEnabled] set to False, which means that [AbstractUnit] can not be used.
+     * @param hideBrokenUnits When set to True will remove [AbstractUnit]s that have
+     * [AbstractUnit.basicUnit] set to [BigDecimal.ZERO] (comes from currencies API).
      * @param chosenUnitGroup If provided will scope list to a specific [UnitGroup].
      * @param favoritesOnly When True will filter only [AbstractUnit]s with [AbstractUnit.isFavorite]
      * set to True.
@@ -135,7 +138,7 @@ class AllUnitsRepository @Inject constructor() {
      * @return Grouped by [UnitGroup] list of [AbstractUnit]s.
      */
     fun filterUnits(
-        hideBrokenCurrencies: Boolean,
+        hideBrokenUnits: Boolean,
         chosenUnitGroup: UnitGroup?,
         favoritesOnly: Boolean,
         searchQuery: String,
@@ -153,8 +156,8 @@ class AllUnitsRepository @Inject constructor() {
         if (favoritesOnly) {
             units = units.filter { it.isFavorite }
         }
-        if (hideBrokenCurrencies) {
-            units = units.filter { it.isEnabled }
+        if (hideBrokenUnits) {
+            units = units.filter { it.basicUnit > BigDecimal.ZERO }
         }
 
         units = when (sorting) {
@@ -198,22 +201,20 @@ class AllUnitsRepository @Inject constructor() {
     /**
      * Update [AbstractUnit.basicUnit] properties for currencies from [currencyCollection].
      *
-     * @param conversions Map: [AbstractUnit.unitId] and [BigDecimal] that will replace current
-     * [AbstractUnit.basicUnit].
+     * @param unitFrom Base unit
      */
-    fun updateBasicUnitsForCurrencies(
-        conversions: Map<String, BigDecimal>
-    ) {
+    suspend fun updateBasicUnitsForCurrencies(
+        unitFrom: AbstractUnit
+    ) = withContext(Dispatchers.IO) {
+        val conversions: Map<String, BigDecimal> = CurrencyApi.retrofitService.getCurrencyPairs(unitFrom.unitId).currency
         getCollectionByGroup(UnitGroup.CURRENCY).forEach {
             // Getting rates from map. We set ZERO as default so that it can be skipped
             val rate = conversions.getOrElse(it.unitId) { BigDecimal.ZERO }
             // We make sure that we don't divide by zero
             if (rate > BigDecimal.ZERO) {
-                it.isEnabled = true
                 it.basicUnit = BigDecimal.ONE.setScale(MAX_PRECISION).div(rate)
             } else {
-                // Hiding broken currencies
-                it.isEnabled = false
+                it.basicUnit = BigDecimal.ZERO
             }
         }
     }

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Acceleration.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val accelerationCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Angle.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val angleCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Area.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val areaCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Capacitance.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val electrostaticCapacitance: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Currency.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val currencyCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Data.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val dataCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/DataTransfer.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val dataTransferCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Energy.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val energyCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/FlowRate.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.FlowRateUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 val flowRateCollection: List<AbstractUnit> by lazy {

data/units/src/main/java/com/sadellie/unitto/data/units/collections/Flux.kt

@@ -18,11 +18,11 @@
 
 package com.sadellie.unitto.data.units.collections
 
+import com.sadellie.unitto.core.base.R
 import com.sadellie.unitto.data.model.AbstractUnit
 import com.sadellie.unitto.data.model.DefaultUnit
 import com.sadellie.unitto.data.model.UnitGroup
 import com.sadellie.unitto.data.units.MyUnitIDS
-import com.sadellie.unitto.data.units.R
 import java.math.BigDecimal
 
 internal val fluxCollection: List<AbstractUnit> by lazy {