space-android/src/main/java/com/owncloud/android/ui/preview/PreviewVideoActivity.java

/*
 *   ownCloud Android client application
 *
 *   @author David A. Velasco
 *   Copyright (C) 2015 ownCloud Inc.
 *
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License version 2,
 *   as published by the Free Software Foundation.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package com.owncloud.android.ui.preview;

import android.content.Intent;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnErrorListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.net.Uri;
import android.os.Bundle;

import com.google.android.exoplayer2.ExoPlayer;
import com.google.android.exoplayer2.MediaItem;
import com.google.android.exoplayer2.ui.StyledPlayerView;
import com.nextcloud.client.media.ErrorFormat;
import com.owncloud.android.R;
import com.owncloud.android.databinding.ActivityPreviewVideoBinding;
import com.owncloud.android.datamodel.OCFile;
import com.owncloud.android.lib.common.utils.Log_OC;
import com.owncloud.android.ui.activity.FileActivity;
import com.owncloud.android.utils.MimeTypeUtil;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AlertDialog;

/**
 *  Activity implementing a basic video player.
 *
 *  Used as an utility to preview video files contained in an ownCloud account.
 *
 *  Currently, it always plays in landscape mode, full screen. When the playback ends,
 *  the activity is finished.
 */
public class PreviewVideoActivity extends FileActivity implements OnCompletionListener, OnPreparedListener, OnErrorListener {

    /** Key to receive a flag signaling if the video should be started immediately */
    public static final String EXTRA_AUTOPLAY = "AUTOPLAY";

    /** Key to receive the position of the playback where the video should be put at start */
    public static final String EXTRA_START_POSITION = "START_POSITION";

    public static final String EXTRA_STREAM_URL = "STREAM_URL";

    private static final String TAG = PreviewVideoActivity.class.getSimpleName();

    private long mSavedPlaybackPosition = -1;         // in the unit time handled by MediaPlayer.getCurrentPosition()
    private boolean mAutoplay;                  // when 'true', the playback starts immediately with the activity
    private ExoPlayer exoPlayer;             // view to play the file; both performs and show the playback
    private Uri mStreamUri;
    private ActivityPreviewVideoBinding binding;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log_OC.v(TAG, "onCreate");

        binding = ActivityPreviewVideoBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

        Bundle extras = getIntent().getExtras();

        if (savedInstanceState == null && extras != null) {
            mSavedPlaybackPosition = extras.getLong(EXTRA_START_POSITION);
            mAutoplay = extras.getBoolean(EXTRA_AUTOPLAY);
            mStreamUri = (Uri) extras.get(EXTRA_STREAM_URL);
        } else if (savedInstanceState != null) {
            mSavedPlaybackPosition = savedInstanceState.getLong(EXTRA_START_POSITION);
            mAutoplay = savedInstanceState.getBoolean(EXTRA_AUTOPLAY);
            mStreamUri = (Uri) savedInstanceState.get(EXTRA_STREAM_URL);
        }

        StyledPlayerView playerView = findViewById(R.id.videoPlayer);
        exoPlayer = new ExoPlayer.Builder(this).build();
        playerView.setPlayer(exoPlayer);

        binding.getRoot().findViewById(R.id.exo_exit_fs).setOnClickListener(v -> onBackPressed());
        binding.getRoot().findViewById(R.id.exo_pause).setOnClickListener(v -> exoPlayer.pause());
        binding.getRoot().findViewById(R.id.exo_play).setOnClickListener(v -> exoPlayer.play());

        if (mSavedPlaybackPosition >= 0) {
            exoPlayer.seekTo(mSavedPlaybackPosition);
        }

        if (getSupportActionBar() != null) {
            getSupportActionBar().hide();
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void onSaveInstanceState(@NonNull Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putLong(PreviewVideoActivity.EXTRA_START_POSITION, exoPlayer.getCurrentPosition());
        outState.putBoolean(PreviewVideoActivity.EXTRA_AUTOPLAY, exoPlayer.isPlaying());
        outState.putParcelable(PreviewVideoActivity.EXTRA_STREAM_URL, mStreamUri);
    }


    @Override
    public void onBackPressed() {
        Log_OC.v(TAG, "onBackPressed");
        Intent i = new Intent();
        i.putExtra(EXTRA_AUTOPLAY, exoPlayer.isPlaying());
        i.putExtra(EXTRA_START_POSITION, exoPlayer.getCurrentPosition());
        setResult(RESULT_OK, i);

        exoPlayer.stop();
        exoPlayer.release();

        super.onBackPressed();
    }


    /**
     * Called when the file is ready to be played.
     *
     * Just starts the playback.
     *
     * @param   mp    {@link MediaPlayer} instance performing the playback.
     */
    @Override
    public void onPrepared(MediaPlayer mp) {
        Log_OC.v(TAG, "onPrepare");
        exoPlayer.seekTo(mSavedPlaybackPosition);
        if (mAutoplay) {
            exoPlayer.play();
        }
    }


    /**
     * Called when the file is finished playing.
     *
     * Rewinds the video
     *
     * @param   mp    {@link MediaPlayer} instance performing the playback.
     */
    @Override
    public void onCompletion(MediaPlayer  mp) {
        exoPlayer.seekTo(0);
    }


    /**
     * Called when an error in playback occurs.
     *
     * @param   mp      {@link MediaPlayer} instance performing the playback.
     * @param   what    Type of error
     * @param   extra   Extra code specific to the error
     */
    @Override
    public boolean onError(MediaPlayer mp, int what, int extra) {
        Log_OC.e(TAG, "Error in video playback, what = " + what + ", extra = " + extra);

        String message = ErrorFormat.toString(this, what, extra);
        new AlertDialog.Builder(this)
            .setMessage(message)
            .setPositiveButton(android.R.string.VideoView_error_button,
                               (dialog, whichButton) -> PreviewVideoActivity.this.onCompletion(null))
            .setCancelable(false)
            .show();
        return true;
    }

    @Override
    protected void onStart() {
        super.onStart();
        if (getAccount() != null) {
            OCFile file = getFile();
            /// Validate handled file  (first image to preview)
            if (file == null) {
                throw new IllegalStateException("Instanced with a NULL OCFile");
            }
            if (!MimeTypeUtil.isVideo(file)) {
                throw new IllegalArgumentException("Non-video file passed as argument");
            }
            file = getStorageManager().getFileById(file.getFileId());
            if (file != null) {
                if (file.isDown()) {
                    exoPlayer.addMediaItem(MediaItem.fromUri(file.getStorageUri()));
                } else {
                    exoPlayer.addMediaItem(MediaItem.fromUri(mStreamUri));
                }

                exoPlayer.prepare();
                exoPlayer.play();
            } else {
                finish();
            }
        } else {
            finish();
        }
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (exoPlayer.isPlaying()) {
            exoPlayer.pause();
        }
    }
}