@Module
@InstallIn(ApplicationComponent::class)
object AppModule {
    private lateinit var database: TaskDatabase

    @Provides
    @Singleton
    fun provideDatabase(
        app: Application,
        @ApplicationScope applicationScope: CoroutineScope
    ): TaskDatabase {
        database = Room.databaseBuilder(app, TaskDatabase::class.java, "task_database")
            .fallbackToDestructiveMigration()
            .addCallback(object : RoomDatabase.Callback() {
                override fun onCreate(db: SupportSQLiteDatabase) {
                    super.onCreate(db)
                    val dao = database.taskDao()

                    applicationScope.launch {
                        dao.insert(Task("Wash the dishes"))
                        dao.insert(Task("Do the laundry"))
                        dao.insert(Task("Buy groceries"))
                        dao.insert(Task("Call mom"))
                    }
                }
            })
            .build()
        return database
    }

    @Provides
    @Singleton
    fun provideTaskDao(db: TaskDatabase) = db.taskDao()

    @ApplicationScope
    @Provides
    @Singleton
    fun provideApplicationScope() = CoroutineScope(SupervisorJob())
}

@Retention(AnnotationRetention.BINARY)
@Qualifier
annotation class ApplicationScope