package com.dmc.callcrm.service

import android.app.Notification
import android.app.Service
import android.content.Context
import android.content.Intent
import android.os.Build
import android.os.IBinder
import androidx.core.app.NotificationCompat
import com.dmc.callcrm.App
import com.dmc.callcrm.R
import com.dmc.callcrm.sync.Syncer
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.SupervisorJob
import kotlinx.coroutines.cancel
import kotlinx.coroutines.launch

/**
 * A lightweight foreground service. It exists mainly to give the app a
 * persistent, OS-visible reason to run so a sync can fire right after a call,
 * even when the app UI is closed. Actual periodic work is done by WorkManager.
 */
class CallMonitorService : Service() {

    private val scope = CoroutineScope(SupervisorJob() + Dispatchers.IO)

    override fun onCreate() {
        super.onCreate()
        startForeground(NOTIF_ID, buildNotification())
    }

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        scope.launch { Syncer.run(applicationContext) }
        return START_STICKY   // restart if the OS kills us
    }

    private fun buildNotification(): Notification =
        NotificationCompat.Builder(this, App.CHANNEL_ID)
            .setContentTitle(getString(R.string.notif_title))
            .setContentText(getString(R.string.notif_text))
            .setSmallIcon(android.R.drawable.stat_sys_upload)
            .setOngoing(true)
            .setPriority(NotificationCompat.PRIORITY_LOW)
            .build()

    override fun onDestroy() {
        scope.cancel()
        super.onDestroy()
    }

    override fun onBind(intent: Intent?): IBinder? = null

    companion object {
        private const val NOTIF_ID = 1001

        fun start(ctx: Context) {
            val i = Intent(ctx, CallMonitorService::class.java)
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                ctx.startForegroundService(i)
            } else {
                ctx.startService(i)
            }
        }
    }
}