/*

 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 */

package com.sun.media.sound;

import javax.sound.sampled.AudioFormat;

import javax.sound.sampled.AudioSystem;

import javax.sound.sampled.Control;

import javax.sound.sampled.DataLine;

import javax.sound.sampled.LineEvent;

import javax.sound.sampled.LineUnavailableException;

/**

 * AbstractDataLine

 *

 * @author Kara Kytle

 */

abstract class AbstractDataLine extends AbstractLine implements DataLine {

    // DEFAULTS

    // default format

    private final AudioFormat defaultFormat;

    // default buffer size in bytes

    private final int defaultBufferSize;

    // the lock for synchronization

    protected final Object lock = new Object();

    // STATE

    // current format

    protected AudioFormat format;

    // current buffer size in bytes

    protected int bufferSize;

    protected boolean running = false;

    private boolean started = false;

    private boolean active = false;

    /**

     * Constructs a new AbstractLine.

     */

    protected AbstractDataLine(DataLine.Info info, AbstractMixer mixer, Control[] controls) {

        this(info, mixer, controls, null, AudioSystem.NOT_SPECIFIED);

    }

    /**

     * Constructs a new AbstractLine.

     */

    protected AbstractDataLine(DataLine.Info info, AbstractMixer mixer, Control[] controls, AudioFormat format, int bufferSize) {

        super(info, mixer, controls);

        // record the default values

        if (format != null) {

            defaultFormat = format;

        } else {

            // default CD-quality

            defaultFormat = new AudioFormat(44100.0f, 16, 2, true, Platform.isBigEndian());

        }

        if (bufferSize > 0) {

            defaultBufferSize = bufferSize;

        } else {

            // 0.5 seconds buffer

            defaultBufferSize = ((int) (defaultFormat.getFrameRate() / 2)) * defaultFormat.getFrameSize();

        }

        // set the initial values to the defaults

        this.format = defaultFormat;

        this.bufferSize = defaultBufferSize;

    }

    // DATA LINE METHODS

    public final void open(AudioFormat format, int bufferSize) throws LineUnavailableException {

        //$$fb 2001-10-09: Bug #4517739: avoiding deadlock by synchronizing to mixer !

        synchronized (mixer) {

            if (Printer.trace) Printer.trace("> AbstractDataLine.open(format, bufferSize) (class: "+getClass().getName());

            // if the line is not currently open, try to open it with this format and buffer size

            if (!isOpen()) {

                // make sure that the format is specified correctly

                // $$fb part of fix for 4679187: Clip.open() throws unexpected Exceptions

                Toolkit.isFullySpecifiedAudioFormat(format);

                if (Printer.debug) Printer.debug("  need to open the mixer...");

                // reserve mixer resources for this line

                //mixer.open(this, format, bufferSize);

                mixer.open(this);

                try {

                    // open the data line.  may throw LineUnavailableException.

                    implOpen(format, bufferSize);

                    // if we succeeded, set the open state to true and send events

                    setOpen(true);

                } catch (LineUnavailableException e) {

                    // release mixer resources for this line and then throw the exception

                    mixer.close(this);

                    throw e;

                }

            } else {

                if (Printer.debug) Printer.debug("  dataline already open");

                // if the line is already open and the requested format differs from the

                // current settings, throw an IllegalStateException

                //$$fb 2002-04-02: fix for 4661602: Buffersize is checked when re-opening line

                if (!format.matches(getFormat())) {

                    throw new IllegalStateException("Line is already open with format " + getFormat() +

                                                    " and bufferSize " + getBufferSize());

                }

                //$$fb 2002-07-26: allow changing the buffersize of already open lines

                if (bufferSize > 0) {

                    setBufferSize(bufferSize);

                }

            }

            if (Printer.trace) Printer.trace("< AbstractDataLine.open(format, bufferSize) completed");

        }

    }

    public final void open(AudioFormat format) throws LineUnavailableException {

        open(format, AudioSystem.NOT_SPECIFIED);

    }

    /**

     * This implementation always returns 0.

     */

    public int available() {

        return 0;

    }

    /**

     * This implementation does nothing.

     */

    public void drain() {

        if (Printer.trace) Printer.trace("AbstractDataLine: drain");

    }

    /**

     * This implementation does nothing.

     */

    public void flush() {

        if (Printer.trace) Printer.trace("AbstractDataLine: flush");

    }

    public final void start() {

        //$$fb 2001-10-09: Bug #4517739: avoiding deadlock by synchronizing to mixer !

        synchronized(mixer) {

            if (Printer.trace) Printer.trace("> "+getClass().getName()+".start() - AbstractDataLine");

            // $$kk: 06.06.99: if not open, this doesn't work....???

            if (isOpen()) {

                if (!isStartedRunning()) {

                    mixer.start(this);

                    implStart();

                    running = true;

                }

            }

        }

        synchronized(lock) {

            lock.notifyAll();

        }

        if (Printer.trace) Printer.trace("< "+getClass().getName()+".start() - AbstractDataLine");

    }

    public final void stop() {

        //$$fb 2001-10-09: Bug #4517739: avoiding deadlock by synchronizing to mixer !

        synchronized(mixer) {

            if (Printer.trace) Printer.trace("> "+getClass().getName()+".stop() - AbstractDataLine");

            // $$kk: 06.06.99: if not open, this doesn't work.

            if (isOpen()) {

                if (isStartedRunning()) {

                    implStop();

                    mixer.stop(this);

                    running = false;

                    // $$kk: 11.10.99: this is not exactly correct, but will probably work

                    if (started && (!isActive())) {

                        setStarted(false);

                    }

                }

            }

        }

        synchronized(lock) {

            lock.notifyAll();

        }

        if (Printer.trace) Printer.trace("< "+getClass().getName()+".stop() - AbstractDataLine");

    }

    // $$jb: 12.10.99: The official API for this is isRunning().

    // Per the denied RFE 4297981,

    // the change to isStarted() is technically an unapproved API change.

    // The 'started' variable is false when playback of data stops.

    // It is changed throughout the implementation with setStarted().

    // This state is what should be returned by isRunning() in the API.

    // Note that the 'running' variable is true between calls to

    // start() and stop().  This state is accessed now through the

    // isStartedRunning() method, defined below.  I have not changed

    // the variable names at this point, since 'running' is accessed

    // in MixerSourceLine and MixerClip, and I want to touch as little

    // code as possible to change isStarted() back to isRunning().

    public final boolean isRunning() {

        return started;

    }

    public final boolean isActive() {

        return active;

    }

    public final long getMicrosecondPosition() {

        long microseconds = getLongFramePosition();

        if (microseconds != AudioSystem.NOT_SPECIFIED) {

            microseconds = Toolkit.frames2micros(getFormat(), microseconds);

        }

        return microseconds;

    }

    public final AudioFormat getFormat() {

        return format;

    }

    public final int getBufferSize() {

        return bufferSize;

    }

    /**

     * This implementation does NOT change the buffer size

     */

    public final int setBufferSize(int newSize) {

        return getBufferSize();

    }

    /**

     * This implementation returns AudioSystem.NOT_SPECIFIED.

     */

    public final float getLevel() {

        return (float)AudioSystem.NOT_SPECIFIED;

    }

    // HELPER METHODS

    /**

     * running is true after start is called and before stop is called,

     * regardless of whether data is actually being presented.

     */

    // $$jb: 12.10.99: calling this method isRunning() conflicts with

    // the official API that was once called isStarted().  Since we

    // use this method throughout the implementation, I am renaming

    // it to isStartedRunning().  This is part of backing out the

    // change denied in RFE 4297981.

    final boolean isStartedRunning() {

        return running;

    }

    /**

     * This method sets the active state and generates

     * events if it changes.

     */

    final void setActive(boolean active) {

        if (Printer.trace) Printer.trace("> AbstractDataLine: setActive(" + active + ")");

        //boolean sendEvents = false;

        //long position = getLongFramePosition();

        synchronized (this) {

            //if (Printer.debug) Printer.debug("    AbstractDataLine: setActive: this.active: " + this.active);

            //if (Printer.debug) Printer.debug("                                 active: " + active);

            if (this.active != active) {

                this.active = active;

                //sendEvents = true;

            }

        }

        //if (Printer.debug) Printer.debug("                                 this.active: " + this.active);

        //if (Printer.debug) Printer.debug("                                 sendEvents: " + sendEvents);

        // $$kk: 11.19.99: take ACTIVE / INACTIVE / EOM events out;

        // putting them in is technically an API change.

        // do not generate ACTIVE / INACTIVE events for now

        // if (sendEvents) {

        //

        //      if (active) {

        //              sendEvents(new LineEvent(this, LineEvent.Type.ACTIVE, position));

        //      } else {

        //              sendEvents(new LineEvent(this, LineEvent.Type.INACTIVE, position));

        //      }

        //}

    }

    /**

     * This method sets the started state and generates

     * events if it changes.

     */

    final void setStarted(boolean started) {

        if (Printer.trace) Printer.trace("> AbstractDataLine: setStarted(" + started + ")");

        boolean sendEvents = false;

        long position = getLongFramePosition();

        synchronized (this) {

            //if (Printer.debug) Printer.debug("    AbstractDataLine: setStarted: this.started: " + this.started);

            //if (Printer.debug) Printer.debug("                                  started: " + started);

            if (this.started != started) {

                this.started = started;

                sendEvents = true;

            }

        }

        //if (Printer.debug) Printer.debug("                                  this.started: " + this.started);

        //if (Printer.debug) Printer.debug("                                  sendEvents: " + sendEvents);

        if (sendEvents) {

            if (started) {

                sendEvents(new LineEvent(this, LineEvent.Type.START, position));

            } else {

                sendEvents(new LineEvent(this, LineEvent.Type.STOP, position));

            }

        }

        if (Printer.trace) Printer.trace("< AbstractDataLine: setStarted completed");

    }

    /**

     * This method generates a STOP event and sets the started state to false.

     * It is here for historic reasons when an EOM event existed.

     */

    final void setEOM() {

        if (Printer.trace) Printer.trace("> AbstractDataLine: setEOM()");

        //$$fb 2002-04-21: sometimes, 2 STOP events are generated.

        // better use setStarted() to send STOP event.

        setStarted(false);

        if (Printer.trace) Printer.trace("< AbstractDataLine: setEOM() completed");

    }

    // OVERRIDES OF ABSTRACT LINE METHODS

    /**

     * Try to open the line with the current format and buffer size values.

     * If the line is not open, these will be the defaults.  If the

     * line is open, this should return quietly because the values

     * requested will match the current ones.

     */

    public final void open() throws LineUnavailableException {

        if (Printer.trace) Printer.trace("> "+getClass().getName()+".open() - AbstractDataLine");

        // this may throw a LineUnavailableException.

        open(format, bufferSize);

        if (Printer.trace) Printer.trace("< "+getClass().getName()+".open() - AbstractDataLine");

    }

    /**

     * This should also stop the line.  The closed line should not be running or active.

     * After we close the line, we reset the format and buffer size to the defaults.

     */

    public final void close() {

        //$$fb 2001-10-09: Bug #4517739: avoiding deadlock by synchronizing to mixer !

        synchronized (mixer) {

            if (Printer.trace) Printer.trace("> "+getClass().getName()+".close() - in AbstractDataLine.");

            if (isOpen()) {

                // stop

                stop();

                // set the open state to false and send events

                setOpen(false);

                // close resources for this line

                implClose();

                // release mixer resources for this line

                mixer.close(this);

                // reset format and buffer size to the defaults

                format = defaultFormat;

                bufferSize = defaultBufferSize;

            }

        }

        if (Printer.trace) Printer.trace("< "+getClass().getName()+".close() - in AbstractDataLine");

    }

    // IMPLEMENTATIONS OF ABSTRACT LINE ABSTRACE METHODS

    // ABSTRACT METHODS

    abstract void implOpen(AudioFormat format, int bufferSize) throws LineUnavailableException;

    abstract void implClose();

    abstract void implStart();

    abstract void implStop();

}