tasks/app/src/main/java/org/tasks/ui/NavigationDrawerViewModel.kt

package org.tasks.ui

import android.content.BroadcastReceiver
import android.content.Context
import android.content.Intent
import androidx.lifecycle.ViewModel
import androidx.lifecycle.viewModelScope
import com.todoroo.astrid.api.Filter
import com.todoroo.astrid.api.Filter.Companion.NO_COUNT
import com.todoroo.astrid.api.FilterListItem
import dagger.hilt.android.lifecycle.HiltViewModel
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.flow.asStateFlow
import kotlinx.coroutines.flow.update
import kotlinx.coroutines.launch
import org.tasks.LocalBroadcastManager
import org.tasks.data.TaskDao
import org.tasks.filters.FilterProvider
import timber.log.Timber
import javax.inject.Inject

@HiltViewModel
class NavigationDrawerViewModel @Inject constructor(
    private val filterProvider: FilterProvider,
    private val taskDao: TaskDao,
    private val localBroadcastManager: LocalBroadcastManager,
) : ViewModel() {
    data class ViewState(
        val selected: Filter? = null,
        val filters: List<FilterListItem> = emptyList(),
    )

    private val _viewState = MutableStateFlow(ViewState())
    private val refreshReceiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context?, intent: Intent?) {
            when (intent?.action) {
                LocalBroadcastManager.REFRESH,
                LocalBroadcastManager.REFRESH_LIST -> updateFilters()
            }
        }
    }

    val viewState: StateFlow<ViewState>
        get() = _viewState.asStateFlow()

    fun setSelected(filter: Filter?) {
        _viewState.update { it.copy(selected = filter) }
    }

    fun updateFilters() = viewModelScope.launch {
        filterProvider
            .navDrawerItems()
            .onEach {
                if (it is Filter && it.count == NO_COUNT) {
                    it.count = try {
                        taskDao.count(it)
                    } catch (e: Exception) {
                        Timber.e(e)
                        0
                    }
                }
            }
            .let { filters -> _viewState.update { it.copy(filters = filters) } }
    }

    override fun onCleared() {
        localBroadcastManager.unregisterReceiver(refreshReceiver)
    }

    init {
        localBroadcastManager.registerRefreshListReceiver(refreshReceiver)
        updateFilters()
    }
}