001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.tools;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.GraphicsEnvironment;
007import java.io.IOException;
008import java.net.URL;
009
010import javax.sound.sampled.AudioFormat;
011import javax.sound.sampled.AudioInputStream;
012import javax.sound.sampled.AudioSystem;
013import javax.sound.sampled.DataLine;
014import javax.sound.sampled.LineUnavailableException;
015import javax.sound.sampled.SourceDataLine;
016import javax.sound.sampled.UnsupportedAudioFileException;
017import javax.swing.JOptionPane;
018
019import org.openstreetmap.josm.Main;
020
021/**
022 * Creates and controls a separate audio player thread.
023 *
024 * @author David Earl <david@frankieandshadow.com>
025 * @since 547
026 */
027public final class AudioPlayer extends Thread {
028
029    private static volatile AudioPlayer audioPlayer;
030
031    private enum State { INITIALIZING, NOTPLAYING, PLAYING, PAUSED, INTERRUPTED }
032
033    private enum Command { PLAY, PAUSE }
034
035    private enum Result { WAITING, OK, FAILED }
036
037    private State state;
038    private URL playingUrl;
039    private final double leadIn; // seconds
040    private final double calibration; // ratio of purported duration of samples to true duration
041    private double position; // seconds
042    private double bytesPerSecond;
043    private static long chunk = 4000; /* bytes */
044    private double speed = 1.0;
045
046    /**
047     * Passes information from the control thread to the playing thread
048     */
049    private class Execute {
050        private Command command;
051        private Result result;
052        private Exception exception;
053        private URL url;
054        private double offset; // seconds
055        private double speed; // ratio
056
057        /*
058         * Called to execute the commands in the other thread
059         */
060        protected void play(URL url, double offset, double speed) throws Exception {
061            this.url = url;
062            this.offset = offset;
063            this.speed = speed;
064            command = Command.PLAY;
065            result = Result.WAITING;
066            send();
067        }
068
069        protected void pause() throws Exception {
070            command = Command.PAUSE;
071            send();
072        }
073
074        private void send() throws Exception {
075            result = Result.WAITING;
076            interrupt();
077            while (result == Result.WAITING) {
078                sleep(10);
079            }
080            if (result == Result.FAILED)
081                throw exception;
082        }
083
084        private void possiblyInterrupt() throws InterruptedException {
085            if (interrupted() || result == Result.WAITING)
086                throw new InterruptedException();
087        }
088
089        protected void failed(Exception e) {
090            exception = e;
091            result = Result.FAILED;
092            state = State.NOTPLAYING;
093        }
094
095        protected void ok(State newState) {
096            result = Result.OK;
097            state = newState;
098        }
099
100        protected double offset() {
101            return offset;
102        }
103
104        protected double speed() {
105            return speed;
106        }
107
108        protected URL url() {
109            return url;
110        }
111
112        protected Command command() {
113            return command;
114        }
115    }
116
117    private final Execute command;
118
119    /**
120     * Plays a WAV audio file from the beginning. See also the variant which doesn't
121     * start at the beginning of the stream
122     * @param url The resource to play, which must be a WAV file or stream
123     * @throws Exception audio fault exception, e.g. can't open stream, unhandleable audio format
124     */
125    public static void play(URL url) throws Exception {
126        AudioPlayer instance = AudioPlayer.getInstance();
127        if (instance != null)
128            instance.command.play(url, 0.0, 1.0);
129    }
130
131    /**
132     * Plays a WAV audio file from a specified position.
133     * @param url The resource to play, which must be a WAV file or stream
134     * @param seconds The number of seconds into the audio to start playing
135     * @throws Exception audio fault exception, e.g. can't open stream, unhandleable audio format
136     */
137    public static void play(URL url, double seconds) throws Exception {
138        AudioPlayer instance = AudioPlayer.getInstance();
139        if (instance != null)
140            instance.command.play(url, seconds, 1.0);
141    }
142
143    /**
144     * Plays a WAV audio file from a specified position at variable speed.
145     * @param url The resource to play, which must be a WAV file or stream
146     * @param seconds The number of seconds into the audio to start playing
147     * @param speed Rate at which audio playes (1.0 = real time, > 1 is faster)
148     * @throws Exception audio fault exception, e.g. can't open stream,  unhandleable audio format
149     */
150    public static void play(URL url, double seconds, double speed) throws Exception {
151        AudioPlayer instance = AudioPlayer.getInstance();
152        if (instance != null)
153            instance.command.play(url, seconds, speed);
154    }
155
156    /**
157     * Pauses the currently playing audio stream. Does nothing if nothing playing.
158     * @throws Exception audio fault exception, e.g. can't open stream,  unhandleable audio format
159     */
160    public static void pause() throws Exception {
161        AudioPlayer instance = AudioPlayer.getInstance();
162        if (instance != null)
163            instance.command.pause();
164    }
165
166    /**
167     * To get the Url of the playing or recently played audio.
168     * @return url - could be null
169     */
170    public static URL url() {
171        AudioPlayer instance = AudioPlayer.getInstance();
172        return instance == null ? null : instance.playingUrl;
173    }
174
175    /**
176     * Whether or not we are paused.
177     * @return boolean whether or not paused
178     */
179    public static boolean paused() {
180        AudioPlayer instance = AudioPlayer.getInstance();
181        return instance == null ? false : (instance.state == State.PAUSED);
182    }
183
184    /**
185     * Whether or not we are playing.
186     * @return boolean whether or not playing
187     */
188    public static boolean playing() {
189        AudioPlayer instance = AudioPlayer.getInstance();
190        return instance == null ? false : (instance.state == State.PLAYING);
191    }
192
193    /**
194     * How far we are through playing, in seconds.
195     * @return double seconds
196     */
197    public static double position() {
198        AudioPlayer instance = AudioPlayer.getInstance();
199        return instance == null ? -1 : instance.position;
200    }
201
202    /**
203     * Speed at which we will play.
204     * @return double, speed multiplier
205     */
206    public static double speed() {
207        AudioPlayer instance = AudioPlayer.getInstance();
208        return instance == null ? -1 : instance.speed;
209    }
210
211    /**
212     * Returns the singleton object, and if this is the first time, creates it along with
213     * the thread to support audio
214     * @return the unique instance
215     */
216    private static AudioPlayer getInstance() {
217        if (audioPlayer != null)
218            return audioPlayer;
219        try {
220            audioPlayer = new AudioPlayer();
221            return audioPlayer;
222        } catch (RuntimeException ex) {
223            Main.error(ex);
224            return null;
225        }
226    }
227
228    /**
229     * Resets the audio player.
230     */
231    public static void reset() {
232        if (audioPlayer != null) {
233            try {
234                pause();
235            } catch (Exception e) {
236                Main.warn(e);
237            }
238            audioPlayer.playingUrl = null;
239        }
240    }
241
242    private AudioPlayer() {
243        state = State.INITIALIZING;
244        command = new Execute();
245        playingUrl = null;
246        leadIn = Main.pref.getDouble("audio.leadin", 1.0 /* default, seconds */);
247        calibration = Main.pref.getDouble("audio.calibration", 1.0 /* default, ratio */);
248        start();
249        while (state == State.INITIALIZING) {
250            yield();
251        }
252    }
253
254    /**
255     * Starts the thread to actually play the audio, per Thread interface
256     * Not to be used as public, though Thread interface doesn't allow it to be made private
257     */
258    @Override public void run() {
259        /* code running in separate thread */
260
261        playingUrl = null;
262        AudioInputStream audioInputStream = null;
263        SourceDataLine audioOutputLine = null;
264        AudioFormat audioFormat;
265        byte[] abData = new byte[(int) chunk];
266
267        for (;;) {
268            try {
269                switch (state) {
270                    case INITIALIZING:
271                        // we're ready to take interrupts
272                        state = State.NOTPLAYING;
273                        break;
274                    case NOTPLAYING:
275                    case PAUSED:
276                        sleep(200);
277                        break;
278                    case PLAYING:
279                        command.possiblyInterrupt();
280                        for (;;) {
281                            int nBytesRead;
282                            nBytesRead = audioInputStream.read(abData, 0, abData.length);
283                            position += nBytesRead / bytesPerSecond;
284                            command.possiblyInterrupt();
285                            if (nBytesRead < 0) {
286                                break;
287                            }
288                            audioOutputLine.write(abData, 0, nBytesRead); // => int nBytesWritten
289                            command.possiblyInterrupt();
290                        }
291                        // end of audio, clean up
292                        audioOutputLine.drain();
293                        audioOutputLine.close();
294                        audioOutputLine = null;
295                        Utils.close(audioInputStream);
296                        audioInputStream = null;
297                        playingUrl = null;
298                        state = State.NOTPLAYING;
299                        command.possiblyInterrupt();
300                        break;
301                    default: // Do nothing
302                }
303            } catch (InterruptedException e) {
304                interrupted(); // just in case we get an interrupt
305                State stateChange = state;
306                state = State.INTERRUPTED;
307                try {
308                    switch (command.command()) {
309                        case PLAY:
310                            double offset = command.offset();
311                            speed = command.speed();
312                            if (playingUrl != command.url() ||
313                                    stateChange != State.PAUSED ||
314                                    offset != 0) {
315                                if (audioInputStream != null) {
316                                    Utils.close(audioInputStream);
317                                }
318                                playingUrl = command.url();
319                                audioInputStream = AudioSystem.getAudioInputStream(playingUrl);
320                                audioFormat = audioInputStream.getFormat();
321                                long nBytesRead;
322                                position = 0.0;
323                                offset -= leadIn;
324                                double calibratedOffset = offset * calibration;
325                                bytesPerSecond = audioFormat.getFrameRate() /* frames per second */
326                                * audioFormat.getFrameSize() /* bytes per frame */;
327                                if (speed * bytesPerSecond > 256_000.0) {
328                                    speed = 256_000 / bytesPerSecond;
329                                }
330                                if (calibratedOffset > 0.0) {
331                                    long bytesToSkip = (long) (calibratedOffset /* seconds (double) */ * bytesPerSecond);
332                                    // skip doesn't seem to want to skip big chunks, so reduce it to smaller ones
333                                    while (bytesToSkip > chunk) {
334                                        nBytesRead = audioInputStream.skip(chunk);
335                                        if (nBytesRead <= 0)
336                                            throw new IOException(tr("This is after the end of the recording"));
337                                        bytesToSkip -= nBytesRead;
338                                    }
339                                    while (bytesToSkip > 0) {
340                                        long skippedBytes = audioInputStream.skip(bytesToSkip);
341                                        bytesToSkip -= skippedBytes;
342                                        if (skippedBytes == 0) {
343                                            // Avoid inifinite loop
344                                            Main.warn("Unable to skip bytes from audio input stream");
345                                            bytesToSkip = 0;
346                                        }
347                                    }
348                                    position = offset;
349                                }
350                                if (audioOutputLine != null) {
351                                    audioOutputLine.close();
352                                }
353                                audioFormat = new AudioFormat(audioFormat.getEncoding(),
354                                        audioFormat.getSampleRate() * (float) (speed * calibration),
355                                        audioFormat.getSampleSizeInBits(),
356                                        audioFormat.getChannels(),
357                                        audioFormat.getFrameSize(),
358                                        audioFormat.getFrameRate() * (float) (speed * calibration),
359                                        audioFormat.isBigEndian());
360                                DataLine.Info info = new DataLine.Info(SourceDataLine.class, audioFormat);
361                                audioOutputLine = (SourceDataLine) AudioSystem.getLine(info);
362                                audioOutputLine.open(audioFormat);
363                                audioOutputLine.start();
364                            }
365                            stateChange = State.PLAYING;
366                            break;
367                        case PAUSE:
368                            stateChange = State.PAUSED;
369                            break;
370                        default: // Do nothing
371                    }
372                    command.ok(stateChange);
373                } catch (LineUnavailableException | IOException | UnsupportedAudioFileException |
374                        SecurityException | IllegalArgumentException startPlayingException) {
375                    Main.error(startPlayingException);
376                    command.failed(startPlayingException); // sets state
377                }
378            } catch (IOException e) {
379                state = State.NOTPLAYING;
380                Main.error(e);
381            }
382        }
383    }
384
385    /**
386     * Shows a popup audio error message for the given exception.
387     * @param ex The exception used as error reason. Cannot be {@code null}.
388     */
389    public static void audioMalfunction(Exception ex) {
390        String msg = ex.getMessage();
391        if (msg == null)
392            msg = tr("unspecified reason");
393        else
394            msg = tr(msg);
395        Main.error(msg);
396        if (!GraphicsEnvironment.isHeadless()) {
397            JOptionPane.showMessageDialog(Main.parent,
398                    "<html><p>" + msg + "</p></html>",
399                    tr("Error playing sound"), JOptionPane.ERROR_MESSAGE);
400        }
401    }
402}