package com.example.onecamera.navigation

import androidx.compose.animation.EnterTransition
import androidx.compose.animation.ExitTransition
import androidx.compose.animation.core.tween
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.hilt.lifecycle.viewmodel.compose.hiltViewModel
import androidx.lifecycle.ViewModel
import androidx.lifecycle.compose.collectAsStateWithLifecycle
import androidx.lifecycle.viewModelScope
import androidx.navigation.NavHostController
import androidx.navigation.compose.NavHost
import androidx.navigation.compose.composable
import androidx.navigation.toRoute
import com.example.onecamera.data.preferences.UserPreferences
import com.example.onecamera.data.preferences.UserPreferencesRepository
import com.example.onecamera.ui.camera.CameraScreen
import com.example.onecamera.ui.folders.FoldersScreen
import com.example.onecamera.ui.gallery.GalleryScreen
import com.example.onecamera.ui.settings.SettingsScreen
import dagger.hilt.android.lifecycle.HiltViewModel
import javax.inject.Inject
import kotlinx.coroutines.flow.SharingStarted
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.flow.stateIn
import kotlinx.serialization.Serializable

@Serializable
object FoldersRoute

@Serializable
data class GalleryRoute(val folderUri: String)

@Serializable
data class CameraRoute(
    val targetFolderUri: String,
    val showTargetGalleryAfterSave: Boolean = false,
)

@Serializable
object SettingsRoute

@HiltViewModel
class NavGraphViewModel @Inject constructor(
    preferencesRepository: UserPreferencesRepository,
) : ViewModel() {
    val preferences: StateFlow<UserPreferences> = preferencesRepository.userPreferencesFlow
        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), UserPreferences())
}

@Composable
fun OneCameraNavGraph(navController: NavHostController) {
    val viewModel: NavGraphViewModel = hiltViewModel()
    val preferences by viewModel.preferences.collectAsStateWithLifecycle()

    val transitionsEnabled = preferences.screenTransitionsEnabled
    androidx.compose.runtime.CompositionLocalProvider(
        com.example.onecamera.ui.components.LocalOneCameraAnimationsEnabled provides transitionsEnabled,
    ) {
    NavHost(
        navController = navController,
        startDestination = FoldersRoute,
        enterTransition = { if (transitionsEnabled) fadeIn(tween(250)) else EnterTransition.None },
        exitTransition = { if (transitionsEnabled) fadeOut(tween(250)) else ExitTransition.None },
        popEnterTransition = { if (transitionsEnabled) fadeIn(tween(250)) else EnterTransition.None },
        popExitTransition = { if (transitionsEnabled) fadeOut(tween(250)) else ExitTransition.None },
    ) {
        composable<FoldersRoute> {
            FoldersScreen(
                onNavigateToGallery = { folderUri ->
                    navController.navigate(GalleryRoute(folderUri))
                },
                onNavigateToCamera = { folderUri ->
                    navController.navigate(
                        CameraRoute(
                            targetFolderUri = folderUri,
                            showTargetGalleryAfterSave = true,
                        ),
                    )
                },
                onNavigateToSettings = {
                    navController.navigate(SettingsRoute)
                },
            )
        }
        composable<GalleryRoute> { backStackEntry ->
            val route = backStackEntry.toRoute<GalleryRoute>()
            GalleryScreen(
                folderUri = route.folderUri,
                onNavigateToCamera = { folderUri ->
                    navController.navigate(CameraRoute(folderUri))
                },
                onNavigateToSubfolder = { folderUri ->
                    navController.navigate(GalleryRoute(folderUri))
                },
                onNavigateBack = { navController.popBackStack() },
            )
        }
        composable<CameraRoute> { backStackEntry ->
            val route = backStackEntry.toRoute<CameraRoute>()
            CameraScreen(
                targetFolderUri = route.targetFolderUri,
                onNavigateBack = { navController.popBackStack() },
                onPhotoSaved = {
                    navController.popBackStack()
                    if (route.showTargetGalleryAfterSave) {
                        navController.navigate(GalleryRoute(route.targetFolderUri))
                    }
                },
            )
        }
        composable<SettingsRoute> {
            SettingsScreen(
                onNavigateBack = { navController.popBackStack() },
            )
        }
    }
    }
}