Clear input as an option

ON by default

closes #117

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

@@ -94,6 +94,8 @@ Used in this dialog window. Should be short -->
     <string name="settings_auto">Auto</string>
     <string name="settings_calculator_support">History view</string>
     <string name="settings_clear_cache">Clear cache</string>
+    <string name="settings_clear_input">Clear input</string>
+    <string name="settings_clear_input_support">Start new expression when clicking \"=\" and clicking any button</string>
     <string name="settings_color_scheme">Color scheme</string>
     <string name="settings_color_theme">Color theme</string>
     <string name="settings_color_theme_support">Pick a theming mode</string>

data/model/src/main/java/com/sadellie/unitto/data/model/repository/UserPreferencesRepository.kt

@@ -86,4 +86,6 @@ interface UserPreferencesRepository {
     suspend fun updatePartialHistoryView(enabled: Boolean)
 
     suspend fun updateAcButton(enabled: Boolean)
+
+    suspend fun updateClearInputAfterEquals(enabled: Boolean)
 }

data/model/src/main/java/com/sadellie/unitto/data/model/userprefs/CalculatorPreferences.kt

@@ -27,4 +27,5 @@ interface CalculatorPreferences {
     val partialHistoryView: Boolean
     val precision: Int
     val outputFormat: Int
+    val clearInputAfterEquals: Boolean
 }

data/userprefs/src/main/java/com/sadellie/unitto/data/userprefs/PreferenceModels.kt

@@ -43,7 +43,6 @@ data class AppPreferencesImpl(
     override val systemFont: Boolean,
 ) : AppPreferences
 
-
 data class GeneralPreferencesImpl(
     override val enableVibrations: Boolean,
 ) : GeneralPreferences
@@ -57,6 +56,7 @@ data class CalculatorPreferencesImpl(
     override val partialHistoryView: Boolean,
     override val precision: Int,
     override val outputFormat: Int,
+    override val clearInputAfterEquals: Boolean,
 ) : CalculatorPreferences
 
 data class ConverterPreferencesImpl(

data/userprefs/src/main/java/com/sadellie/unitto/data/userprefs/PrefsKeys.kt

@@ -47,4 +47,5 @@ internal object PrefsKeys {
     val SYSTEM_FONT = booleanPreferencesKey("SYSTEM_FONT_PREF_KEY")
     val PARTIAL_HISTORY_VIEW = booleanPreferencesKey("PARTIAL_HISTORY_VIEW_PREF_KEY")
     val AC_BUTTON = booleanPreferencesKey("AC_BUTTON_PREF_KEY")
+    val CLEAR_INPUT_AFTER_EQUALS = booleanPreferencesKey("CLEAR_INPUT_AFTER_EQUALS_PREF_KEY")
 }

data/userprefs/src/main/java/com/sadellie/unitto/data/userprefs/UserPreferences.kt

@@ -85,6 +85,7 @@ class UserPreferencesRepositoryImpl @Inject constructor(
                 precision = preferences.getDigitsPrecision(),
                 outputFormat = preferences.getOutputFormat(),
                 acButton = preferences.getAcButton(),
+                clearInputAfterEquals = preferences.getClearInputAfterEquals()
             )
         }
 
@@ -280,6 +281,12 @@ class UserPreferencesRepositoryImpl @Inject constructor(
             preferences[PrefsKeys.AC_BUTTON] = enabled
         }
     }
+
+    override suspend fun updateClearInputAfterEquals(enabled: Boolean) {
+        dataStore.edit { preferences ->
+            preferences[PrefsKeys.CLEAR_INPUT_AFTER_EQUALS] = enabled
+        }
+    }
 }
 
 private fun Preferences.getEnableDynamicTheme(): Boolean {
@@ -376,6 +383,10 @@ private fun Preferences.getAcButton(): Boolean {
     return this[PrefsKeys.AC_BUTTON] ?: false
 }
 
+private fun Preferences.getClearInputAfterEquals(): Boolean {
+    return this[PrefsKeys.CLEAR_INPUT_AFTER_EQUALS] ?: true
+}
+
 private inline fun <T, R> T.letTryOrNull(block: (T) -> R): R? = try {
     this?.let(block)
 } catch (e: Exception) {

feature/calculator/src/main/java/com/sadellie/unitto/feature/calculator/CalculatorViewModel.kt

@@ -120,36 +120,39 @@ internal class CalculatorViewModel @Inject constructor(
         .stateIn(viewModelScope, CalculatorUIState.Loading)
 
     fun addTokens(tokens: String) = _input.update {
-        val newValue = if (_equalClicked.value) {
+        val clearInputAfterEquals = _prefs.value?.clearInputAfterEquals ?: true
-            _equalClicked.update { false }
+        val newValue = if (_equalClicked.value and clearInputAfterEquals) {
             TextFieldValue().addTokens(tokens)
         } else {
             it.addTokens(tokens)
         }
+        _equalClicked.update { false }
         _fractionJob?.cancel()
         savedStateHandle[_inputKey] = newValue.text
         newValue
     }
 
     fun addBracket() = _input.update {
-        val newValue = if (_equalClicked.value) {
+        val clearInputAfterEquals = _prefs.value?.clearInputAfterEquals ?: true
-            _equalClicked.update { false }
+        val newValue = if (_equalClicked.value and clearInputAfterEquals) {
             TextFieldValue().addBracket()
         } else {
             it.addBracket()
         }
+        _equalClicked.update { false }
         _fractionJob?.cancel()
         savedStateHandle[_inputKey] = newValue.text
         newValue
     }
 
     fun deleteTokens() = _input.update {
-        val newValue = if (_equalClicked.value) {
+        val clearInputAfterEquals = _prefs.value?.clearInputAfterEquals ?: true
-            _equalClicked.update { false }
+        val newValue = if (_equalClicked.value and clearInputAfterEquals) {
             TextFieldValue().deleteTokens()
         } else {
             it.deleteTokens()
         }
+        _equalClicked.update { false }
         _fractionJob?.cancel()
         savedStateHandle[_inputKey] = newValue.text
         newValue

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/calculator/CalculatorSettingsScreen.kt

@@ -20,6 +20,7 @@ package com.sadellie.unitto.feature.settings.calculator
 
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.Backspace
 import androidx.compose.material.icons.filled.Timer
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.stringResource
@@ -47,7 +48,8 @@ internal fun CalculatorSettingsRoute(
             CalculatorSettingsScreen(
                 prefs = prefs,
                 navigateUpAction = navigateUpAction,
-                updatePartialHistoryView = viewModel::updatePartialHistoryView
+                updatePartialHistoryView = viewModel::updatePartialHistoryView,
+                updateClearInputAfterEquals = viewModel::updateClearInputAfterEquals,
             )
         }
     }
@@ -58,6 +60,7 @@ private fun CalculatorSettingsScreen(
     prefs: CalculatorPreferences,
     navigateUpAction: () -> Unit,
     updatePartialHistoryView: (Boolean) -> Unit,
+    updateClearInputAfterEquals: (Boolean) -> Unit,
 ) {
     UnittoScreenWithLargeTopBar(
         title = stringResource(R.string.calculator_title),
@@ -73,6 +76,16 @@ private fun CalculatorSettingsScreen(
                     onSwitchChange = updatePartialHistoryView
                 )
             }
+
+            item("clear input") {
+                UnittoListItem(
+                    headlineText = stringResource(R.string.settings_clear_input),
+                    icon = Icons.AutoMirrored.Filled.Backspace,
+                    supportingText = stringResource(R.string.settings_clear_input_support),
+                    switchState = prefs.clearInputAfterEquals,
+                    onSwitchChange = updateClearInputAfterEquals
+                )
+            }
         }
     }
 }
@@ -90,8 +103,10 @@ private fun PreviewCalculatorSettingsScreen() {
             precision = 3,
             outputFormat = OutputFormat.PLAIN,
             acButton = true,
+            clearInputAfterEquals = true,
         ),
         navigateUpAction = {},
-        updatePartialHistoryView = {}
+        updatePartialHistoryView = {},
+        updateClearInputAfterEquals = {},
     )
 }

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/calculator/CalculatorViewModel.kt

@@ -36,4 +36,8 @@ class CalculatorViewModel @Inject constructor(
     fun updatePartialHistoryView(enabled: Boolean) = viewModelScope.launch {
         userPrefsRepository.updatePartialHistoryView(enabled)
     }
+
+    fun updateClearInputAfterEquals(enabled: Boolean) = viewModelScope.launch {
+        userPrefsRepository.updateClearInputAfterEquals(enabled)
+    }
 }