source: main/trunk/model-sites-dev/respooled/collect/popup-video-respooled/js/midi/inc/shim/WebAudioAPI.js@ 29863

/**
 * @license -------------------------------------------------------------------
 *   module: WebAudioShim - Fix naming issues for WebAudioAPI supports
 *      src: https://github.com/Dinahmoe/webaudioshim
 *   author: Dinahmoe AB
 * -------------------------------------------------------------------
 * Copyright (c) 2012 DinahMoe AB
 * 
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

window.AudioContext = window.AudioContext || window.webkitAudioContext || null;
window.OfflineAudioContext = window.OfflineAudioContext || window.webkitOfflineAudioContext || null;

(function (Context) {
    var isFunction = function (f) {
        return Object.prototype.toString.call(f) === "[object Function]" ||
            Object.prototype.toString.call(f) === "[object AudioContextConstructor]";
    };
    var contextMethods = [
        ["createGainNode", "createGain"],
        ["createDelayNode", "createDelay"],
        ["createJavaScriptNode", "createScriptProcessor"]
    ];
    ///
    var proto;
    var instance;
    var sourceProto;
    ///
    if (!isFunction(Context)) {
        return;
    }
    instance = new Context();
    if (!instance.destination || !instance.sampleRate) {
        return;
    }
    proto = Context.prototype;
    sourceProto = Object.getPrototypeOf(instance.createBufferSource());

    if (!isFunction(sourceProto.start)) {
        if (isFunction(sourceProto.noteOn)) {
            sourceProto.start = function (when, offset, duration) {
                switch (arguments.length) {
                    case 0:
                        throw new Error("Not enough arguments.");
                    case 1:
                        this.noteOn(when);
                        break;
                    case 2:
                        if (this.buffer) {
                            this.noteGrainOn(when, offset, this.buffer.duration - offset);
                        } else {
                            throw new Error("Missing AudioBuffer");
                        }
                        break;
                    case 3:
                        this.noteGrainOn(when, offset, duration);
                }
            };
        }
    }

    if (!isFunction(sourceProto.noteOn)) {
        sourceProto.noteOn = sourceProto.start;
    }

    if (!isFunction(sourceProto.noteGrainOn)) {
        sourceProto.noteGrainOn = sourceProto.start;
    }

    if (!isFunction(sourceProto.stop)) {
        sourceProto.stop = sourceProto.noteOff;
    }

    if (!isFunction(sourceProto.noteOff)) {
        sourceProto.noteOff = sourceProto.stop;
    }

    contextMethods.forEach(function (names) {
        var name1;
        var name2;
        while (names.length) {
            name1 = names.pop();
            if (isFunction(this[name1])) {
                this[names.pop()] = this[name1];
            } else {
                name2 = names.pop();
                this[name1] = this[name2];
            }
        }
    }, proto);
})(window.AudioContext);