package de.wechselbild.wallpaper

import android.app.NotificationChannel
import android.app.NotificationManager
import android.app.PendingIntent
import android.app.Service
import android.content.BroadcastReceiver
import android.content.Context
import android.content.Intent
import android.content.IntentFilter
import android.os.Build
import android.os.IBinder
import androidx.core.app.NotificationCompat
import androidx.core.content.ContextCompat
import java.util.concurrent.Executors

class WallpaperRotationService : Service() {
  private val worker = Executors.newSingleThreadExecutor()
  private val screenReceiver = object : BroadcastReceiver() {
    override fun onReceive(context: Context, intent: Intent) {
      if (intent.action == Intent.ACTION_SCREEN_ON && WallpaperStore.enabled(context)) worker.execute { WallpaperStore.applyNext(context) }
    }
  }

  override fun onCreate() {
    super.onCreate()
    createChannel()
    val launch = packageManager.getLaunchIntentForPackage(packageName)
    val pending = PendingIntent.getActivity(this, 0, launch, PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT)
    val notification = NotificationCompat.Builder(this, CHANNEL)
      .setSmallIcon(android.R.drawable.ic_menu_gallery)
      .setContentTitle("Wechselbild ist aktiv")
      .setContentText("Das Motiv wechselt beim Aktivieren des Displays.")
      .setOngoing(true).setSilent(true).setContentIntent(pending).build()
    startForeground(NOTIFICATION_ID, notification)
    ContextCompat.registerReceiver(this, screenReceiver, IntentFilter(Intent.ACTION_SCREEN_ON), ContextCompat.RECEIVER_NOT_EXPORTED)
  }

  override fun onStartCommand(intent: Intent?, flags: Int, startId: Int) = START_STICKY
  override fun onBind(intent: Intent?): IBinder? = null
  override fun onDestroy() { runCatching { unregisterReceiver(screenReceiver) }; worker.shutdown(); super.onDestroy() }

  private fun createChannel() {
    if (Build.VERSION.SDK_INT >= 26) {
      val channel = NotificationChannel(CHANNEL, "Automatischer Bildwechsel", NotificationManager.IMPORTANCE_LOW)
      getSystemService(NotificationManager::class.java).createNotificationChannel(channel)
    }
  }

  companion object {
    private const val CHANNEL = "wechselbild_rotation"
    private const val NOTIFICATION_ID = 4217
    fun start(context: Context) = ContextCompat.startForegroundService(context, Intent(context, WallpaperRotationService::class.java))
    fun stop(context: Context) { context.stopService(Intent(context, WallpaperRotationService::class.java)) }
  }
}