package com.example.sergey.notiremove

import android.app.Activity
import android.app.NotificationChannel
import android.app.NotificationManager
import android.app.PendingIntent
import android.content.ContentValues
import android.content.Context
import android.content.Intent
import android.database.Cursor
import android.database.sqlite.SQLiteDatabase
import android.graphics.Color
import android.os.Bundle
import android.support.v4.app.NotificationCompat
import android.support.v4.app.TaskStackBuilder
import android.util.Log
import android.view.View
import android.view.View.OnClickListener
import android.widget.Button

class MainActivity : Activity(), OnClickListener {

    var channelId = "my_channel_01"  // accommodate API >= 26

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // ---I deliberately left out onClick attributes in XML, to connect up the buttons
        //   at runtime. This is excessive. Instead, just add  android:onClick="onClick"
        //   to the activity_main layout and remove the redundant OnClickListener from Activity.
        val b1 : Button = findViewById(R.id.button1)
        b1.setOnClickListener( { v: View -> this.onClick(v) } ) // spurious lambda, type checks;
                                                                // can be converted to a reference, this::onClick

        // also not necessary if XML of Button 2 has onClick set as above
        val b2 : Button = findViewById(R.id.button2)
        b2.setOnClickListener(this)
        // ---end excessive code

        createChannel(channelId)
    }

    // This handler function is called for both buttons, but can distinguish
    //   which one was pressed, by checking the ID of the View passed in as argument
    //   (which will be either Button 1 or Button 2).
    override fun onClick(v: View) {
        Log.d("Notify", "onClick() called" + v.id.toString())
        when (v.id) {
            R.id.button1 -> createAndGenerateNotifcation()
            R.id.button2 -> RemoveAllNotifications()
        }
    }

    fun createAndGenerateNotifcation() {

        Log.d("Notify", "createAndGenerateNotifcation() called")

        // This works for APIs >= 15, due to using NotificationCompat rather than Notification
        val mBuilder : NotificationCompat.Builder
            = NotificationCompat.Builder(
                this, channelId).setSmallIcon(R.drawable.ic_launcher)
                .setContentTitle("Notification Title").setContentText("Body")

        mBuilder.setAutoCancel(true)  // notification goes away if clicked

        val resultIntent = Intent()

        // See https://developer.android.com/training/notify-user/navigation.html
        val stackBuilder : TaskStackBuilder = TaskStackBuilder.create(this)
        stackBuilder.addNextIntent(resultIntent)

        val notiId : Long = System.currentTimeMillis()  // use system time for IDs of notifications
        insertNotificationIntoDb(notiId)

        var resultPendingIntent : PendingIntent
                = stackBuilder.getPendingIntent(0, // 0 causes bugs on some systems!
                                                 PendingIntent.FLAG_UPDATE_CURRENT);
        mBuilder.setContentIntent(resultPendingIntent)

        var mNotificationManager : NotificationManager =
                getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        mNotificationManager.notify(notiId.toInt(), mBuilder.build())
    }

    // This code uses a SQLite database to keep track of notification IDs persistently,
    //   to cancel each one of them individually.
    //   This is overkill, because notifications can be all cancelled at once with
    //     cancelAll().
    fun insertNotificationIntoDb(id: Long) {

        Log.d("Notify", "insetNotificationIntoDb() called")
        
        var mBase : DataBase = DataBase(this)
        var cValues : ContentValues = ContentValues()   // what a SQL database query expects for a row

        cValues.put("noti_id", id);  // values for this table's new row

        var db : SQLiteDatabase = mBase.getWritableDatabase()
        var i = db.insert("noti", null, cValues);

        Log.i("Insert", i.toString())
        try {
            db.close();
        } catch ( e : Exception) {
            Log.d("Exception", "caught exception in insertNotifi")
        }
    }

    fun RemoveAllNotifications() {
        var mBase : DataBase = DataBase(this);

        var cur : Cursor = mBase.getWritableDatabase().query("noti", null, null,
                null, null, null, null, null)

        cur.moveToFirst();

        var mNotificationManager : NotificationManager
                = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        do {
            var id : Int = cur.getInt(0);

            mNotificationManager.cancel(id);

        } while (cur.moveToNext());

        try {
            cur.close();
        } catch ( e : Exception) {
            Log.d("Exception", "caught exception in RemoveAllNotification")
        }
    }

    private fun createChannel(id: String) {
        if (android.os.Build.VERSION.SDK_INT >= 26) {
            val mNotificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
            // The user-visible name of the channel.
            val importance = NotificationManager.IMPORTANCE_LOW
            val mChannel = NotificationChannel(id, "Notify Channel", importance)
            // Configure the notification channel.
            mChannel.description = "My Notification Channel"
            mChannel.enableLights(true)
            // Sets the notification light color for notifications posted to this
            // channel, if the device supports this feature.
            mChannel.lightColor = Color.RED
            mChannel.enableVibration(true)
            mChannel.vibrationPattern = longArrayOf(100, 200, 300, 400, 500, 400, 300, 200, 400)
            mNotificationManager.createNotificationChannel(mChannel)
        }
    }
}