teapod/app/src/main/java/org/mosad/teapod/PlayerActivity.kt

package org.mosad.teapod

import android.net.Uri
import android.os.Build
import android.os.Bundle
import android.util.Log
import android.view.View
import android.view.WindowInsets
import android.view.WindowInsetsController
import androidx.appcompat.app.AppCompatActivity
import com.google.android.exoplayer2.ExoPlayer
import com.google.android.exoplayer2.MediaItem
import com.google.android.exoplayer2.Player
import com.google.android.exoplayer2.SimpleExoPlayer
import com.google.android.exoplayer2.source.hls.HlsMediaSource
import com.google.android.exoplayer2.upstream.DataSource
import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory
import com.google.android.exoplayer2.util.Util
import kotlinx.android.synthetic.main.activity_player.*


class PlayerActivity : AppCompatActivity() {

    private lateinit var player: SimpleExoPlayer
    private lateinit var dataSourceFactory: DataSource.Factory

    private var streamUrl = ""

    private var playWhenReady = true
    private var currentWindow = 0
    private var playbackPosition: Long = 0


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_player)
        hideBars() // Initial hide the bars

        savedInstanceState?.let {
            currentWindow = it.getInt(getString(R.string.state_resume_window))
            playbackPosition = it.getLong(getString(R.string.state_resume_position))
            playWhenReady = it.getBoolean(getString(R.string.state_is_playing))
        }

        streamUrl = intent.getStringExtra(getString(R.string.intent_stream_url)).toString()
    }


    override fun onStart() {
        super.onStart()
        if (Util.SDK_INT > 23) {
            initPlayer()
            if (video_view != null) video_view.onResume()
        }
    }

    override fun onResume() {
        super.onResume()
        if (Util.SDK_INT <= 23) {
            initPlayer()
            if (video_view != null) video_view.onResume()
        }
    }

    override fun onPause() {
        super.onPause()
        if (Util.SDK_INT <= 23) {
            if (video_view != null) video_view.onPause()
            releasePlayer()
        }
    }

    override fun onStop() {
        super.onStop()
        if (Util.SDK_INT > 23) {
            if (video_view != null) video_view.onPause()
            releasePlayer()
        }
    }

    override fun onSaveInstanceState(outState: Bundle) {
        outState.putInt(getString(R.string.state_resume_window), currentWindow)
        outState.putLong(getString(R.string.state_resume_position), playbackPosition)
        outState.putBoolean(getString(R.string.state_is_playing), playWhenReady)
        super.onSaveInstanceState(outState)
    }

    private fun initPlayer() {
        if (streamUrl.isEmpty()) {
            Log.e(javaClass.name, "No stream url was set.")
            return
        }

        player = SimpleExoPlayer.Builder(this).build()
        dataSourceFactory = DefaultDataSourceFactory(this, Util.getUserAgent(this, "Teapod"))

        val mediaSource = HlsMediaSource.Factory(dataSourceFactory)
            .createMediaSource(MediaItem.fromUri(Uri.parse(streamUrl)))

        player.playWhenReady = playWhenReady
        player.setMediaSource(mediaSource)
        player.seekTo(playbackPosition)
        player.prepare()


        player.addListener(object : Player.EventListener {
            override fun onPlaybackStateChanged(state: Int) {
                super.onPlaybackStateChanged(state)

                loading.visibility = when (state) {
                    ExoPlayer.STATE_READY -> View.GONE
                    ExoPlayer.STATE_BUFFERING -> View.VISIBLE
                    else -> View.GONE
                }
            }
        })

        // when the player controls get hidden, hide the bars too
        video_view.setControllerVisibilityListener {
            if (it == View.GONE) hideBars()
        }

        video_view.player = player
    }

    private fun releasePlayer(){
        playbackPosition = player.currentPosition
        currentWindow = player.currentWindowIndex
        playWhenReady = player.playWhenReady
        player.release()
    }

    /**
     * hide the status and navigation bar
     */
    private fun hideBars() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
            window.setDecorFitsSystemWindows(false)
            window.insetsController?.apply {
                hide(WindowInsets.Type.statusBars() or WindowInsets.Type.navigationBars())
                systemBarsBehavior = WindowInsetsController.BEHAVIOR_SHOW_BARS_BY_SWIPE
            }
        } else {
            @Suppress("deprecation")
            window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_IMMERSIVE
                    or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                    or View.SYSTEM_UI_FLAG_FULLSCREEN)
        }
    }
}