vyatsu-schedule/app/src/main/java/agzam/vyatsu/AppRoot.kt

package agzam.vyatsu

import agzam.vyatsu.di.AppContainer
import agzam.vyatsu.ui.groups.GroupPickerScreen
import agzam.vyatsu.ui.groups.GroupPickerViewModel
import agzam.vyatsu.ui.home.HomeScreen
import agzam.vyatsu.ui.schedule.ScheduleViewModel
import androidx.compose.runtime.Composable
import androidx.compose.runtime.collectAsState
import androidx.compose.runtime.getValue
import androidx.compose.ui.platform.LocalContext
import androidx.lifecycle.ViewModel
import androidx.lifecycle.ViewModelProvider
import androidx.lifecycle.viewmodel.compose.viewModel

@Composable
fun AppRoot() {
    val app = LocalContext.current.applicationContext as VyatsuApplication
    val container = app.container

    val scheduleViewModel: ScheduleViewModel = viewModel(factory = scheduleFactory(container))
    val groupPickerViewModel: GroupPickerViewModel = viewModel(factory = groupPickerFactory(container))

    val state by scheduleViewModel.uiState.collectAsState()

    if (state.noGroup) {
        GroupPickerScreen(
            viewModel = groupPickerViewModel,
            onGroupPicked = { group -> scheduleViewModel.selectGroup(group.id) }
        )
        return
    }
    HomeScreen(
        scheduleViewModel = scheduleViewModel,
        onSwitchGroup = { scheduleViewModel.switchGroup() }
    )
}

private class SimpleFactory<T : ViewModel>(private val create: () -> T) : ViewModelProvider.Factory {
    @Suppress("UNCHECKED_CAST")
    override fun <T : ViewModel> create(modelClass: Class<T>): T = create() as T
}

private fun scheduleFactory(c: AppContainer): ViewModelProvider.Factory = SimpleFactory { ScheduleViewModel(c.scheduleRepository, c.preferencesRepository) }
private fun groupPickerFactory(c: AppContainer): ViewModelProvider.Factory = SimpleFactory { GroupPickerViewModel(c.groupRepository) }