/*
 * 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

import androidx.compose.animation.core.tween
import androidx.compose.material3.DrawerValue
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
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
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.luminance
import androidx.hilt.navigation.compose.hiltViewModel
import androidx.lifecycle.compose.collectAsStateWithLifecycle
import androidx.navigation.NavDestination.Companion.hierarchy
import androidx.navigation.NavGraph.Companion.findStartDestination
import androidx.navigation.compose.currentBackStackEntryAsState
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.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.feature.converter.ConverterViewModel
import com.sadellie.unitto.feature.settings.SettingsViewModel
import com.sadellie.unitto.feature.unitslist.UnitsListViewModel
import io.github.sadellie.themmo.Themmo
import io.github.sadellie.themmo.rememberThemmoController
import kotlinx.coroutines.launch

@Composable
internal fun UnittoApp() {
    val converterViewModel: ConverterViewModel = hiltViewModel()
    val unitsListViewModel: UnitsListViewModel = hiltViewModel()
    val settingsViewModel: SettingsViewModel = hiltViewModel()
    val userPrefs = settingsViewModel.userPrefs.collectAsStateWithLifecycle()

    val themmoController = rememberThemmoController(
        lightColorScheme = LightThemeColors,
        darkColorScheme = DarkThemeColors,
        // Anything below will not be called if theming mode is still loading from DataStore
        themingMode = userPrefs.value.themingMode ?: return,
        dynamicThemeEnabled = userPrefs.value.enableDynamicTheme,
        amoledThemeEnabled = userPrefs.value.enableAmoledTheme,
        customColor = userPrefs.value.customColor,
        monetMode = userPrefs.value.monetMode
    )
    val navController = rememberNavController()
    val sysUiController = rememberSystemUiController()

    // Navigation drawer stuff
    val drawerState = rememberDrawerState(DrawerValue.Closed)
    val drawerScope = rememberCoroutineScope()
    val mainTabs = listOf(DrawerItems.Calculator, DrawerItems.Converter)
    val additionalTabs = listOf(DrawerItems.Settings)

    val navBackStackEntry by navController.currentBackStackEntryAsState()
    val currentRoute: TopLevelDestinations? by remember(navBackStackEntry?.destination) {
        derivedStateOf {
            val hierarchyRoutes = navBackStackEntry?.destination?.hierarchy?.map { it.route }
                ?: emptySequence()

            (mainTabs + additionalTabs)
                .map { it.destination }
                .firstOrNull {
                    hierarchyRoutes.contains(it.route)
                }
        }
    }
    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,
        typography = AppTypography,
        animationSpec = tween(250)
    ) {
        val backgroundColor = MaterialTheme.colorScheme.background
        val useDarkIcons by remember(backgroundColor) {
            mutableStateOf(backgroundColor.luminance() > 0.5f)
        }

        ModalNavigationDrawer(
            drawerState = drawerState,
            gesturesEnabled = gesturesEnabled,
            drawerContent = {
                UnittoDrawerSheet(
                    modifier = Modifier,
                    mainTabs = mainTabs,
                    additionalTabs = additionalTabs,
                    currentDestination = currentRoute
                ) {
                    drawerScope.launch { drawerState.close() }
                    navController.navigate(it) {
                        popUpTo(navController.graph.findStartDestination().id) {
                            saveState = true
                        }
                        launchSingleTop = true
                        restoreState = true
                    }
                }
            }
        ) {
            UnittoNavigation(
                navController = navController,
                converterViewModel = converterViewModel,
                unitsListViewModel = unitsListViewModel,
                settingsViewModel = settingsViewModel,
                themmoController = it,
                startDestination = userPrefs.value.startingScreen,
                openDrawer = { drawerScope.launch { drawerState.open() } }
            )
        }

        LaunchedEffect(useDarkIcons) {
            sysUiController.setNavigationBarColor(Color.Transparent, useDarkIcons)
            sysUiController.setStatusBarColor(Color.Transparent, useDarkIcons)
        }
    }
}