lib/common/plugin/Media.js

var utils = require('cordova/utils'),
    exec = require('cordova/exec');

var mediaObjects = {};

/**
 * This class provides access to the device media, interfaces to both sound and video
 *
 * @constructor
 * @param src                   The file name or url to play
 * @param successCallback       The callback to be called when the file is done playing or recording.
 *                                  successCallback()
 * @param errorCallback         The callback to be called if there is an error.
 *                                  errorCallback(int errorCode) - OPTIONAL
 * @param statusCallback        The callback to be called when media status has changed.
 *                                  statusCallback(int statusCode) - OPTIONAL
 */
var Media = function(src, successCallback, errorCallback, statusCallback) {

    // successCallback optional
    if (successCallback && (typeof successCallback !== "function")) {
        console.log("Media Error: successCallback is not a function");
        return;
    }

    // errorCallback optional
    if (errorCallback && (typeof errorCallback !== "function")) {
        console.log("Media Error: errorCallback is not a function");
        return;
    }

    // statusCallback optional
    if (statusCallback && (typeof statusCallback !== "function")) {
        console.log("Media Error: statusCallback is not a function");
        return;
    }

    this.id = utils.createUUID();
    mediaObjects[this.id] = this;
    this.src = src;
    this.successCallback = successCallback;
    this.errorCallback = errorCallback;
    this.statusCallback = statusCallback;
    this._duration = -1;
    this._position = -1;
    exec(null, this.errorCallback, "Media", "create", [this.id, this.src]);
};

// Media messages
Media.MEDIA_STATE = 1;
Media.MEDIA_DURATION = 2;
Media.MEDIA_POSITION = 3;
Media.MEDIA_ERROR = 9;

// Media states
Media.MEDIA_NONE = 0;
Media.MEDIA_STARTING = 1;
Media.MEDIA_RUNNING = 2;
Media.MEDIA_PAUSED = 3;
Media.MEDIA_STOPPED = 4;
Media.MEDIA_MSG = ["None", "Starting", "Running", "Paused", "Stopped"];

// "static" function to return existing objs.
Media.get = function(id) {
    return mediaObjects[id];
};

/**
 * Start or resume playing audio file.
 */
Media.prototype.play = function(options) {
    exec(null, null, "Media", "startPlayingAudio", [this.id, this.src, options]);
};

/**
 * Stop playing audio file.
 */
Media.prototype.stop = function() {
    var me = this;
    exec(function() {
        me._position = 0;
        me.successCallback();
    }, this.errorCallback, "Media", "stopPlayingAudio", [this.id]);
};

/**
 * Seek or jump to a new time in the track..
 */
Media.prototype.seekTo = function(milliseconds) {
    var me = this;
    exec(function(p) {
        me._position = p;
    }, this.errorCallback, "Media", "seekToAudio", [this.id, milliseconds]);
};

/**
 * Pause playing audio file.
 */
Media.prototype.pause = function() {
    exec(null, this.errorCallback, "Media", "pausePlayingAudio", [this.id]);
};

/**
 * Get duration of an audio file.
 * The duration is only set for audio that is playing, paused or stopped.
 *
 * @return      duration or -1 if not known.
 */
Media.prototype.getDuration = function() {
    return this._duration;
};

/**
 * Get position of audio.
 */
Media.prototype.getCurrentPosition = function(success, fail) {
    var me = this;
    exec(function(p) {
        me._position = p;
        success(p);
    }, fail, "Media", "getCurrentPositionAudio", [this.id]);
};

/**
 * Start recording audio file.
 */
Media.prototype.startRecord = function() {
    exec(this.successCallback, this.errorCallback, "Media", "startRecordingAudio", [this.id, this.src]);
};

/**
 * Stop recording audio file.
 */
Media.prototype.stopRecord = function() {
    exec(this.successCallback, this.errorCallback, "Media", "stopRecordingAudio", [this.id]);
};

/**
 * Release the resources.
 */
Media.prototype.release = function() {
    exec(null, this.errorCallback, "Media", "release", [this.id]);
};

/**
 * Adjust the volume.
 */
Media.prototype.setVolume = function(volume) {
    exec(null, null, "Media", "setVolume", [this.id, volume]);
};

/**
 * Audio has status update.
 * PRIVATE
 *
 * @param id            The media object id (string)
 * @param status        The status code (int)
 * @param msg           The status message (string)
 */
Media.onStatus = function(id, msg, value) {
    var media = mediaObjects[id];
    // If state update
    if (msg === Media.MEDIA_STATE) {
        if (value === Media.MEDIA_STOPPED) {
            if (media.successCallback) {
                media.successCallback();
            }
        }
        if (media.statusCallback) {
            media.statusCallback(value);
        }
    }
    else if (msg === Media.MEDIA_DURATION) {
        media._duration = value;
    }
    else if (msg === Media.MEDIA_ERROR) {
        if (media.errorCallback) {
            // value should be a MediaError object when msg == MEDIA_ERROR
            media.errorCallback(value);
        }
    }
    else if (msg === Media.MEDIA_POSITION) {
        media._position = value;
    }
};

module.exports = Media;