source: main/trunk/model-sites-dev/respooled/collect/popup-video-respooled/js/midi/util/dom_request_script.js@ 29863

/*
    -----------------------------------------------------------
    dom.loadScript.js : 0.1.4 : 2014/02/12 : http://mudcu.be
    -----------------------------------------------------------
    Copyright 2011-2014 Mudcube. All rights reserved.
    -----------------------------------------------------------
    /// No verification
    dom.loadScript.add("../js/jszip/jszip.js");
    /// Strict loading order and verification.
    dom.loadScript.add({
        strictOrder: true,
        urls: [
            {
                url: "../js/jszip/jszip.js",
                verify: "JSZip",
                onsuccess: function() {
                    console.log(1)
                }
            },
            { 
                url: "../inc/downloadify/js/swfobject.js",
                verify: "swfobject",
                onsuccess: function() {
                    console.log(2)
                }
            }
        ],
        onsuccess: function() {
            console.log(3)
        }
    });
    /// Just verification.
    dom.loadScript.add({
        url: "../js/jszip/jszip.js",
        verify: "JSZip",
        onsuccess: function() {
            console.log(1)
        }
    });
*/

if (typeof(dom) === "undefined") var dom = {};

(function() { "use strict";

dom.loadScript = function() {
    this.loaded = {};
    this.loading = {};
    return this;
};

dom.loadScript.prototype.add = function(config) {
    var that = this;
    if (typeof(config) === "string") {
        config = { url: config };
    }
    var urls = config.urls;
    if (typeof(urls) === "undefined") {
        urls = [{ 
            url: config.url, 
            verify: config.verify
        }];
    }
    /// adding the elements to the head
    var doc = document.getElementsByTagName("head")[0];
    /// 
    var testElement = function(element, test) {
        if (that.loaded[element.url]) return;
        if (test && globalExists(test) === false) return;
        that.loaded[element.url] = true;
        //
        if (that.loading[element.url]) that.loading[element.url]();
        delete that.loading[element.url];
        //
        if (element.onsuccess) element.onsuccess();
        if (typeof(getNext) !== "undefined") getNext();
    };
    ///
    var hasError = false;
    var batchTest = [];
    var addElement = function(element) {
        if (typeof(element) === "string") {
            element = {
                url: element,
                verify: config.verify
            };
        }
        if (/([\w\d.\[\]\'\"])$/.test(element.verify)) { // check whether its a variable reference
            var verify = element.test = element.verify;
            if (typeof(verify) === "object") {
                for (var n = 0; n < verify.length; n ++) {
                    batchTest.push(verify[n]);
                }           
            } else {
                batchTest.push(verify);
            }
        }
        if (that.loaded[element.url]) return;
        var script = document.createElement("script");
        script.onreadystatechange = function() {
            if (this.readyState !== "loaded" && this.readyState !== "complete") return;
            testElement(element);
        };
        script.onload = function() {
            testElement(element);
        };
        script.onerror = function() {
            hasError = true;
            delete that.loading[element.url];
            if (typeof(element.test) === "object") {
                for (var key in element.test) {
                    removeTest(element.test[key]);
                }           
            } else {
                removeTest(element.test);
            }
        };
        script.setAttribute("type", "text/javascript");
        script.setAttribute("src", element.url);
        doc.appendChild(script);
        that.loading[element.url] = function() {};
    };
    /// checking to see whether everything loaded properly
    var removeTest = function(test) {
        var ret = [];
        for (var n = 0; n < batchTest.length; n ++) {
            if (batchTest[n] === test) continue;
            ret.push(batchTest[n]);
        }
        batchTest = ret;
    };
    var onLoad = function(element) {
        if (element) {
            testElement(element, element.test);
        } else {
            for (var n = 0; n < urls.length; n ++) {
                testElement(urls[n], urls[n].test);
            }
        }
        var istrue = true;
        for (var n = 0; n < batchTest.length; n ++) {
            if (globalExists(batchTest[n]) === false) {
                istrue = false;
            }
        }
        if (!config.strictOrder && istrue) { // finished loading all the requested scripts
            if (hasError) {
                if (config.error) {
                    config.error();
                }
            } else if (config.onsuccess) {
                config.onsuccess();
            }
        } else { // keep calling back the function
            setTimeout(function() { //- should get slower over time?
                onLoad(element);
            }, 10);
        }
    };
    /// loading methods;  strict ordering or loose ordering
    if (config.strictOrder) {
        var ID = -1;
        var getNext = function() {
            ID ++;
            if (!urls[ID]) { // all elements are loaded
                if (hasError) {
                    if (config.error) {
                        config.error();
                    }
                } else if (config.onsuccess) {
                    config.onsuccess();
                }
            } else { // loading new script
                var element = urls[ID];
                var url = element.url;
                if (that.loading[url]) { // already loading from another call (attach to event)
                    that.loading[url] = function() {
                        if (element.onsuccess) element.onsuccess();
                        getNext();
                    }
                } else if (!that.loaded[url]) { // create script element
                    addElement(element);
                    onLoad(element);
                } else { // it's already been successfully loaded
                    getNext();
                }
            }
        };
        getNext();
    } else { // loose ordering
        for (var ID = 0; ID < urls.length; ID ++) {
            addElement(urls[ID]);
            onLoad(urls[ID]);
        }
    }
};

dom.loadScript = new dom.loadScript();

var globalExists = function(path, root) {
    try {
        path = path.split('"').join('').split("'").join('').split(']').join('').split('[').join('.');
        var parts = path.split(".");
        var length = parts.length;
        var object = root || window;
        for (var n = 0; n < length; n ++) {
            var key = parts[n];
            if (object[key] == null) {
                return false;
            } else { //
                object = object[key];
            }
        }
        return true;
    } catch(e) {
        return false;
    }
};

})();

/// For NodeJS
if (typeof (module) !== "undefined" && module.exports) {
    module.exports = dom.loadScript;
}