/js/mage/adminhtml/loader.js

/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Academic Free License (AFL 3.0)
 * that is bundled with this package in the file LICENSE_AFL.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/afl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magento.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magento.com for more information.
 *
 * @category    Mage
 * @package     Mage_Adminhtml
 * @copyright   Copyright (c) 2006-2016 X.commerce, Inc. and affiliates (http://www.magento.com)
 * @license     http://opensource.org/licenses/afl-3.0.php  Academic Free License (AFL 3.0)
 */

var SessionError = Class.create();
SessionError.prototype = {
    initialize: function(errorText) {
        this.errorText = errorText;
    },
    toString: function()
    {
        return 'Session Error:' + this.errorText;
    }
};

Ajax.Request.addMethods({
    initialize: function($super, url, options){
        $super(options);
        this.transport = Ajax.getTransport();
        if (!url.match(new RegExp('[?&]isAjax=true',''))) {
            url = url.match(new RegExp('\\?',"g")) ? url + '&isAjax=true' : url + '?isAjax=true';
        }
        if (Object.isString(this.options.parameters)
            && this.options.parameters.indexOf('form_key=') == -1
        ) {
            this.options.parameters += '&' + Object.toQueryString({
                form_key: FORM_KEY
            });
        } else {
            if (!this.options.parameters) {
                this.options.parameters = {
                    form_key: FORM_KEY
                };
            }
            if (!this.options.parameters.form_key) {
                this.options.parameters.form_key = FORM_KEY;
            }
        }

        this.request(url);
    },
    respondToReadyState: function(readyState) {
        var state = Ajax.Request.Events[readyState], response = new Ajax.Response(this);

        if (state == 'Complete') {
            try {
                this._complete = true;
                if (response.responseText.isJSON()) {
                    var jsonObject = response.responseText.evalJSON();
                    if (jsonObject.ajaxExpired && jsonObject.ajaxRedirect) {
                        window.location.replace(jsonObject.ajaxRedirect);
                        throw new SessionError('session expired');
                    }
                }

                (this.options['on' + response.status]
                 || this.options['on' + (this.success() ? 'Success' : 'Failure')]
                 || Prototype.emptyFunction)(response, response.headerJSON);
            } catch (e) {
                this.dispatchException(e);
                if (e instanceof SessionError) {
                    return;
                }
            }

            var contentType = response.getHeader('Content-type');
            if (this.options.evalJS == 'force'
                || (this.options.evalJS && this.isSameOrigin() && contentType
                && contentType.match(/^\s*(text|application)\/(x-)?(java|ecma)script(;.*)?\s*$/i))) {
                this.evalResponse();
            }
        }

        try {
            (this.options['on' + state] || Prototype.emptyFunction)(response, response.headerJSON);
            Ajax.Responders.dispatch('on' + state, this, response, response.headerJSON);
        } catch (e) {
            this.dispatchException(e);
        }

        if (state == 'Complete') {
            // avoid memory leak in MSIE: clean up
            this.transport.onreadystatechange = Prototype.emptyFunction;
        }
    }
});

Ajax.Updater.respondToReadyState = Ajax.Request.respondToReadyState;
//Ajax.Updater = Object.extend(Ajax.Updater, {
//  initialize: function($super, container, url, options) {
//    this.container = {
//      success: (container.success || container),
//      failure: (container.failure || (container.success ? null : container))
//    };
//
//    options = Object.clone(options);
//    var onComplete = options.onComplete;
//    options.onComplete = (function(response, json) {
//      this.updateContent(response.responseText);
//      if (Object.isFunction(onComplete)) onComplete(response, json);
//    }).bind(this);
//
//    $super((url.match(new RegExp('\\?',"g")) ? url + '&isAjax=1' : url + '?isAjax=1'), options);
//  }
//});

var varienLoader = new Class.create();

varienLoader.prototype = {
    initialize : function(caching){
        this.callback= false;
        this.cache   = $H();
        this.caching = caching || false;
        this.url     = false;
    },

    getCache : function(url){
        if(this.cache.get(url)){
            return this.cache.get(url)
        }
        return false;
    },

    load : function(url, params, callback){
        this.url      = url;
        this.callback = callback;

        if(this.caching){
            var transport = this.getCache(url);
            if(transport){
                this.processResult(transport);
                return;
            }
        }

        if (typeof(params.updaterId) != 'undefined') {
            new varienUpdater(params.updaterId, url, {
                evalScripts : true,
                onComplete: this.processResult.bind(this),
                onFailure: this._processFailure.bind(this)
            });
        }
        else {
            new Ajax.Request(url,{
                method: 'post',
                parameters: params || {},
                onComplete: this.processResult.bind(this),
                onFailure: this._processFailure.bind(this)
            });
        }
    },

    _processFailure : function(transport){
        location.href = BASE_URL;
    },

    processResult : function(transport){
        if(this.caching){
            this.cache.set(this.url, transport);
        }
        if(this.callback){
            this.callback(transport.responseText);
        }
    }
}

if (!window.varienLoaderHandler)
    var varienLoaderHandler = new Object();

varienLoaderHandler.handler = {
    onCreate: function(request) {
        if(request.options.loaderArea===false){
            return;
        }

        request.options.loaderArea = $$('#html-body .wrapper')[0]; // Blocks all page

        if(request && request.options.loaderArea){
            Element.clonePosition($('loading-mask'), $(request.options.loaderArea), {offsetLeft:-2})
            toggleSelectsUnderBlock($('loading-mask'), false);
            Element.show('loading-mask');
            setLoaderPosition();
            if(request.options.loaderArea=='html-body'){
                //Element.show('loading-process');
            }
        }
        else{
            //Element.show('loading-process');
        }
    },

    onComplete: function(transport) {
        if(Ajax.activeRequestCount == 0) {
            //Element.hide('loading-process');
            toggleSelectsUnderBlock($('loading-mask'), true);
            Element.hide('loading-mask');
        }
    }
};

/**
 * @todo need calculate middle of visible area and scroll bind
 */
function setLoaderPosition(){
    var elem = $('loading_mask_loader');
    if (elem && Prototype.Browser.IE) {
        var elementDims = elem.getDimensions();
        var viewPort = document.viewport.getDimensions();
        var offsets = document.viewport.getScrollOffsets();
        elem.style.left = Math.floor(viewPort.width / 2 + offsets.left - elementDims.width / 2) + 'px';
        elem.style.top = Math.floor(viewPort.height / 2 + offsets.top - elementDims.height / 2) + 'px';
        elem.style.position = 'absolute';
    }
}

/*function getRealHeight() {
    var body = document.body;
    if (window.innerHeight && window.scrollMaxY) {
        return window.innerHeight + window.scrollMaxY;
    }
    return Math.max(body.scrollHeight, body.offsetHeight);
}*/



function toggleSelectsUnderBlock(block, flag){
    if(Prototype.Browser.IE){
        var selects = document.getElementsByTagName("select");
        for(var i=0; i<selects.length; i++){
            /**
             * @todo: need check intersection
             */
            if(flag){
                if(selects[i].needShowOnSuccess){
                    selects[i].needShowOnSuccess = false;
                    // Element.show(selects[i])
                    selects[i].style.visibility = '';
                }
            }
            else{
                if(Element.visible(selects[i])){
                    // Element.hide(selects[i]);
                    selects[i].style.visibility = 'hidden';
                    selects[i].needShowOnSuccess = true;
                }
            }
        }
    }
}

Ajax.Responders.register(varienLoaderHandler.handler);

var varienUpdater = Class.create(Ajax.Updater, {
    updateContent: function($super, responseText) {
        if (responseText.isJSON()) {
            var responseJSON = responseText.evalJSON();
            if (responseJSON.ajaxExpired && responseJSON.ajaxRedirect) {
                window.location.replace(responseJSON.ajaxRedirect);
            }
        } else {
            $super(responseText);
        }
    }
});