/**
 * alertifyjs 1.11.4 http://alertifyjs.com
 * AlertifyJS is a javascript framework for developing pretty browser dialogs and notifications.
 * Copyright 2019 Mohammad Younes <Mohammad@alertifyjs.com> (http://alertifyjs.com) 
 * Licensed under GPL 3 <https://opensource.org/licenses/gpl-3.0>*/
( function ( window ) {
    'use strict';
    
    /**
     * Keys enum
     * @type {Object}
     */
    var keys = {
        ENTER: 13,
        ESC: 27,
        F1: 112,
        F12: 123,
        LEFT: 37,
        RIGHT: 39
    };
    /**
     * Default options 
     * @type {Object}
     */
    var defaults = {
        autoReset:true,
        basic:false,
        closable:true,
        closableByDimmer:true,
        frameless:false,
        maintainFocus:true, //global default not per instance, applies to all dialogs
        maximizable:true,
        modal:true,
        movable:true,
        moveBounded:false,
        overflow:true,
        padding: true,
        pinnable:true,
        pinned:true,
        preventBodyShift:false, //global default not per instance, applies to all dialogs
        resizable:true,
        startMaximized:false,
        transition:'pulse',
        notifier:{
            delay:5,
            position:'bottom-right',
            closeButton:false
        },
        glossary:{
            title:'AlertifyJS',
            ok: 'OK',
            cancel: 'Cancel',
            acccpt: 'Accept',
            deny: 'Deny',
            confirm: 'Confirm',
            decline: 'Decline',
            close: 'Close',
            maximize: 'Maximize',
            restore: 'Restore',
        },
        theme:{
            input:'ajs-input',
            ok:'ajs-ok',
            cancel:'ajs-cancel',
        }
    };
    
    //holds open dialogs instances
    var openDialogs = [];

    /**
     * [Helper]  Adds the specified class(es) to the element.
     *
     * @element {node}      The element
     * @className {string}  One or more space-separated classes to be added to the class attribute of the element.
     * 
     * @return {undefined}
     */
    function addClass(element,classNames){
        element.className += ' ' + classNames;
    }
    
    /**
     * [Helper]  Removes the specified class(es) from the element.
     *
     * @element {node}      The element
     * @className {string}  One or more space-separated classes to be removed from the class attribute of the element.
     * 
     * @return {undefined}
     */
    function removeClass(element, classNames) {
        var original = element.className.split(' ');
        var toBeRemoved = classNames.split(' ');
        for (var x = 0; x < toBeRemoved.length; x += 1) {
            var index = original.indexOf(toBeRemoved[x]);
            if (index > -1){
                original.splice(index,1);
            }
        }
        element.className = original.join(' ');
    }

    /**
     * [Helper]  Checks if the document is RTL
     *
     * @return {Boolean} True if the document is RTL, false otherwise.
     */
    function isRightToLeft(){
        return window.getComputedStyle(document.body).direction === 'rtl';
    }
    /**
     * [Helper]  Get the document current scrollTop
     *
     * @return {Number} current document scrollTop value
     */
    function getScrollTop(){
        return ((document.documentElement && document.documentElement.scrollTop) || document.body.scrollTop);
    }

    /**
     * [Helper]  Get the document current scrollLeft
     *
     * @return {Number} current document scrollLeft value
     */
    function getScrollLeft(){
        return ((document.documentElement && document.documentElement.scrollLeft) || document.body.scrollLeft);
    }

    /**
    * Helper: clear contents
    *
    */
    function clearContents(element){
        while (element.lastChild) {
            element.removeChild(element.lastChild);
        }
    }
    /**
     * Extends a given prototype by merging properties from base into sub.
     *
     * @sub {Object} sub The prototype being overwritten.
     * @base {Object} base The prototype being written.
     *
     * @return {Object} The extended prototype.
     */
    function copy(src) {
        if(null === src){
            return src;
        }
        var cpy;
        if(Array.isArray(src)){
            cpy = [];
            for(var x=0;x<src.length;x+=1){
                cpy.push(copy(src[x]));
            }
            return cpy;
        }
      
        if(src instanceof Date){
            return new Date(src.getTime());
        }
      
        if(src instanceof RegExp){
            cpy = new RegExp(src.source);
            cpy.global = src.global;
            cpy.ignoreCase = src.ignoreCase;
            cpy.multiline = src.multiline;
            cpy.lastIndex = src.lastIndex;
            return cpy;
        }
        
        if(typeof src === 'object'){
            cpy = {};
            // copy dialog pototype over definition.
            for (var prop in src) {
                if (src.hasOwnProperty(prop)) {
                    cpy[prop] = copy(src[prop]);
                }
            }
            return cpy;
        }
        return src;
    }
    /**
      * Helper: destruct the dialog
      *
      */
    function destruct(instance, initialize){
        if(instance.elements){
            //delete the dom and it's references.
            var root = instance.elements.root;
            root.parentNode.removeChild(root);
            delete instance.elements;
            //copy back initial settings.
            instance.settings = copy(instance.__settings);
            //re-reference init function.
            instance.__init = initialize;
            //delete __internal variable to allow re-initialization.
            delete instance.__internal;
        }
    }

    /**
     * Use a closure to return proper event listener method. Try to use
     * `addEventListener` by default but fallback to `attachEvent` for
     * unsupported browser. The closure simply ensures that the test doesn't
     * happen every time the method is called.
     *
     * @param    {Node}     el    Node element
     * @param    {String}   event Event type
     * @param    {Function} fn    Callback of event
     * @return   {Function}
     */
    var on = (function () {
        if (document.addEventListener) {
            return function (el, event, fn, useCapture) {
                el.addEventListener(event, fn, useCapture === true);
            };
        } else if (document.attachEvent) {
            return function (el, event, fn) {
                el.attachEvent('on' + event, fn);
            };
        }
    }());

    /**
     * Use a closure to return proper event listener method. Try to use
     * `removeEventListener` by default but fallback to `detachEvent` for
     * unsupported browser. The closure simply ensures that the test doesn't
     * happen every time the method is called.
     *
     * @param    {Node}     el    Node element
     * @param    {String}   event Event type
     * @param    {Function} fn    Callback of event
     * @return   {Function}
     */
    var off = (function () {
        if (document.removeEventListener) {
            return function (el, event, fn, useCapture) {
                el.removeEventListener(event, fn, useCapture === true);
            };
        } else if (document.detachEvent) {
            return function (el, event, fn) {
                el.detachEvent('on' + event, fn);
            };
        }
    }());

    /**
     * Prevent default event from firing
     *
     * @param  {Event} event Event object
     * @return {undefined}

    function prevent ( event ) {
        if ( event ) {
            if ( event.preventDefault ) {
                event.preventDefault();
            } else {
                event.returnValue = false;
            }
        }
    }
    */
    var transition = (function () {
        var t, type;
        var supported = false;
        var transitions = {
            'animation'        : 'animationend',
            'OAnimation'       : 'oAnimationEnd oanimationend',
            'msAnimation'      : 'MSAnimationEnd',
            'MozAnimation'     : 'animationend',
            'WebkitAnimation'  : 'webkitAnimationEnd'
        };

        for (t in transitions) {
            if (document.documentElement.style[t] !== undefined) {
                type = transitions[t];
                supported = true;
                break;
            }
        }

        return {
            type: type,
            supported: supported
        };
    }());

    /**
    * Creates event handler delegate that sends the instance as last argument.
    * 
    * @return {Function}    a function wrapper which sends the instance as last argument.
    */
    function delegate(context, method) {
        return function () {
            if (arguments.length > 0) {
                var args = [];
                for (var x = 0; x < arguments.length; x += 1) {
                    args.push(arguments[x]);
                }
                args.push(context);
                return method.apply(context, args);
            }
            return method.apply(context, [null, context]);
        };
    }
    /**
    * Helper for creating a dialog close event.
    * 
    * @return {object}
    */
    function createCloseEvent(index, button) {
        return {
            index: index,
            button: button,
            cancel: false
        };
    }
    /**
    * Helper for dispatching events.
    *
    * @param  {string} evenType The type of the event to disptach.
    * @param  {object} instance The dialog instance disptaching the event.
    *
    * @return   {any}   The result of the invoked function.
    */
    function dispatchEvent(eventType, instance) {
        if ( typeof instance.get(eventType) === 'function' ) {
            return instance.get(eventType).call(instance);
        }
    }


    /**
     * Super class for all dialogs
     *
     * @return {Object}		base dialog prototype
     */
    var dialog = (function () {
        var //holds the list of used keys.
            usedKeys = [],
            //dummy variable, used to trigger dom reflow.
            reflow = null,
            //holds body tab index in case it has any.
            tabindex = false,
            //condition for detecting safari
            isSafari = window.navigator.userAgent.indexOf('Safari') > -1 && window.navigator.userAgent.indexOf('Chrome') < 0,
            //dialog building blocks
            templates = {
                dimmer:'<div class="ajs-dimmer"></div>',
                /*tab index required to fire click event before body focus*/
                modal: '<div class="ajs-modal" tabindex="0"></div>',
                dialog: '<div class="ajs-dialog" tabindex="0"></div>',
                reset: '<button class="ajs-reset"></button>',
                commands: '<div class="ajs-commands"><button class="ajs-pin"></button><button class="ajs-maximize"></button><button class="ajs-close"></button></div>',
                header: '<div class="ajs-header"></div>',
                body: '<div class="ajs-body"></div>',
                content: '<div class="ajs-content"></div>',
                footer: '<div class="ajs-footer"></div>',
                buttons: { primary: '<div class="ajs-primary ajs-buttons"></div>', auxiliary: '<div class="ajs-auxiliary ajs-buttons"></div>' },
                button: '<button class="ajs-button"></button>',
                resizeHandle: '<div class="ajs-handle"></div>',
            },
            //common class names
            classes = {
                animationIn: 'ajs-in',
                animationOut: 'ajs-out',
                base: 'alertify',
                basic:'ajs-basic',
                capture: 'ajs-capture',
                closable:'ajs-closable',
                fixed: 'ajs-fixed',
                frameless:'ajs-frameless',
                hidden: 'ajs-hidden',
                maximize: 'ajs-maximize',
                maximized: 'ajs-maximized',
                maximizable:'ajs-maximizable',
                modeless: 'ajs-modeless',
                movable: 'ajs-movable',
                noSelection: 'ajs-no-selection',
                noOverflow: 'ajs-no-overflow',
                noPadding:'ajs-no-padding',
                pin:'ajs-pin',
                pinnable:'ajs-pinnable',
                prefix: 'ajs-',
                resizable: 'ajs-resizable',
                restore: 'ajs-restore',
                shake:'ajs-shake',
                unpinned:'ajs-unpinned',
            };

        /**
         * Helper: initializes the dialog instance
         * 
         * @return	{Number}	The total count of currently open modals.
         */
        function initialize(instance){
            
            if(!instance.__internal){

                //no need to expose init after this.
                delete instance.__init;
              
                //keep a copy of initial dialog settings
                if(!instance.__settings){
                    instance.__settings = copy(instance.settings);
                }
                
                //get dialog buttons/focus setup
                var setup;
                if(typeof instance.setup === 'function'){
                    setup = instance.setup();
                    setup.options = setup.options  || {};
                    setup.focus = setup.focus  || {};
                }else{
                    setup = {
                        buttons:[],
                        focus:{
                            element:null,
                            select:false
                        },
                        options:{
                        }
                    };
                }
                
                //initialize hooks object.
                if(typeof instance.hooks !== 'object'){
                    instance.hooks = {};
                }

                //copy buttons defintion
                var buttonsDefinition = [];
                if(Array.isArray(setup.buttons)){
                    for(var b=0;b<setup.buttons.length;b+=1){
                        var ref  = setup.buttons[b],
                            cpy = {};
                        for (var i in ref) {
                            if (ref.hasOwnProperty(i)) {
                                cpy[i] = ref[i];
                            }
                        }
                        buttonsDefinition.push(cpy);
                    }
                }

                var internal = instance.__internal = {
                    /**
                     * Flag holding the open state of the dialog
                     * 
                     * @type {Boolean}
                     */
                    isOpen:false,
                    /**
                     * Active element is the element that will receive focus after
                     * closing the dialog. It defaults as the body tag, but gets updated
                     * to the last focused element before the dialog was opened.
                     *
                     * @type {Node}
                     */
                    activeElement:document.body,
                    timerIn:undefined,
                    timerOut:undefined,
                    buttons: buttonsDefinition,
                    focus: setup.focus,
                    options: {
                        title: undefined,
                        modal: undefined,
                        basic:undefined,
                        frameless:undefined,
                        pinned: undefined,
                        movable: undefined,
                        moveBounded:undefined,
                        resizable: undefined,
                        autoReset: undefined,
                        closable: undefined,
                        closableByDimmer: undefined,
                        maximizable: undefined,
                        startMaximized: undefined,
                        pinnable: undefined,
                        transition: undefined,
                        padding:undefined,
                        overflow:undefined,
                        onshow:undefined,
                        onclosing:undefined,
                        onclose:undefined,
                        onfocus:undefined,
                        onmove:undefined,
                        onmoved:undefined,
                        onresize:undefined,
                        onresized:undefined,
                        onmaximize:undefined,
                        onmaximized:undefined,
                        onrestore:undefined,
                        onrestored:undefined
                    },
                    resetHandler:undefined,
                    beginMoveHandler:undefined,
                    beginResizeHandler:undefined,
                    bringToFrontHandler:undefined,
                    modalClickHandler:undefined,
                    buttonsClickHandler:undefined,
                    commandsClickHandler:undefined,
                    transitionInHandler:undefined,
                    transitionOutHandler:undefined,
                    destroy:undefined
                };

                var elements = {};
                //root node
                elements.root = document.createElement('div');
                //prevent FOUC in case of async styles loading.
                elements.root.style.display = 'none';
                elements.root.className = classes.base + ' ' + classes.hidden + ' ';

                elements.root.innerHTML = templates.dimmer + templates.modal;
                
                //dimmer
                elements.dimmer = elements.root.firstChild;

                //dialog
                elements.modal = elements.root.lastChild;
                elements.modal.innerHTML = templates.dialog;
                elements.dialog = elements.modal.firstChild;
                elements.dialog.innerHTML = templates.reset + templates.commands + templates.header + templates.body + templates.footer + templates.resizeHandle + templates.reset;

                //reset links
                elements.reset = [];
                elements.reset.push(elements.dialog.firstChild);
                elements.reset.push(elements.dialog.lastChild);
                
                //commands
                elements.commands = {};
                elements.commands.container = elements.reset[0].nextSibling;
                elements.commands.pin = elements.commands.container.firstChild;
                elements.commands.maximize = elements.commands.pin.nextSibling;
                elements.commands.close = elements.commands.maximize.nextSibling;
                
                //header
                elements.header = elements.commands.container.nextSibling;

                //body
                elements.body = elements.header.nextSibling;
                elements.body.innerHTML = templates.content;
                elements.content = elements.body.firstChild;

                //footer
                elements.footer = elements.body.nextSibling;
                elements.footer.innerHTML = templates.buttons.auxiliary + templates.buttons.primary;
                
                //resize handle
                elements.resizeHandle = elements.footer.nextSibling;

                //buttons
                elements.buttons = {};
                elements.buttons.auxiliary = elements.footer.firstChild;
                elements.buttons.primary = elements.buttons.auxiliary.nextSibling;
                elements.buttons.primary.innerHTML = templates.button;
                elements.buttonTemplate = elements.buttons.primary.firstChild;
                //remove button template
                elements.buttons.primary.removeChild(elements.buttonTemplate);
                               
                for(var x=0; x < instance.__internal.buttons.length; x+=1) {
                    var button = instance.__internal.buttons[x];
                    
                    // add to the list of used keys.
                    if(usedKeys.indexOf(button.key) < 0){
                        usedKeys.push(button.key);
                    }

                    button.element = elements.buttonTemplate.cloneNode();
                    button.element.innerHTML = button.text;
                    if(typeof button.className === 'string' &&  button.className !== ''){
                        addClass(button.element, button.className);
                    }
                    for(var key in button.attrs){
                        if(key !== 'className' && button.attrs.hasOwnProperty(key)){
                            button.element.setAttribute(key, button.attrs[key]);
                        }
                    }
                    if(button.scope === 'auxiliary'){
                        elements.buttons.auxiliary.appendChild(button.element);
                    }else{
                        elements.buttons.primary.appendChild(button.element);
                    }
                }
                //make elements pubic
                instance.elements = elements;
                
                //save event handlers delegates
                internal.resetHandler = delegate(instance, onReset);
                internal.beginMoveHandler = delegate(instance, beginMove);
                internal.beginResizeHandler = delegate(instance, beginResize);
                internal.bringToFrontHandler = delegate(instance, bringToFront);
                internal.modalClickHandler = delegate(instance, modalClickHandler);
                internal.buttonsClickHandler = delegate(instance, buttonsClickHandler);
                internal.commandsClickHandler = delegate(instance, commandsClickHandler);
                internal.transitionInHandler = delegate(instance, handleTransitionInEvent);
                internal.transitionOutHandler = delegate(instance, handleTransitionOutEvent);

                //settings
                for(var opKey in internal.options){
                    if(setup.options[opKey] !== undefined){
                        // if found in user options
                        instance.set(opKey, setup.options[opKey]);
                    }else if(alertify.defaults.hasOwnProperty(opKey)) {
                        // else if found in defaults options
                        instance.set(opKey, alertify.defaults[opKey]);
                    }else if(opKey === 'title' ) {
                        // else if title key, use alertify.defaults.glossary
                        instance.set(opKey, alertify.defaults.glossary[opKey]);
                    }
                }

                // allow dom customization
                if(typeof instance.build === 'function'){
                    instance.build();
                }
            }
            
            //add to the end of the DOM tree.
            document.body.appendChild(instance.elements.root);
        }

        /**
         * Helper: maintains scroll position
         *
         */
        var scrollX, scrollY;
        function saveScrollPosition(){
            scrollX = getScrollLeft();
            scrollY = getScrollTop();
        }
        function restoreScrollPosition(){
            window.scrollTo(scrollX, scrollY);
        }

        /**
         * Helper: adds/removes no-overflow class from body
         *
         */
        function ensureNoOverflow(){
            var requiresNoOverflow = 0;
            for(var x=0;x<openDialogs.length;x+=1){
                var instance = openDialogs[x];
                if(instance.isModal() || instance.isMaximized()){
                    requiresNoOverflow+=1;
                }
            }
            if(requiresNoOverflow === 0 && document.body.className.indexOf(classes.noOverflow) >= 0){
                //last open modal or last maximized one
                removeClass(document.body, classes.noOverflow);
                preventBodyShift(false);
            }else if(requiresNoOverflow > 0 && document.body.className.indexOf(classes.noOverflow) < 0){
                //first open modal or first maximized one
                preventBodyShift(true);
                addClass(document.body, classes.noOverflow);
            }
        }
        var top = '', topScroll = 0;
        /**
         * Helper: prevents body shift.
         *
         */
        function preventBodyShift(add){
            if(alertify.defaults.preventBodyShift){
                if(add && document.documentElement.scrollHeight > document.documentElement.clientHeight ){//&& openDialogs[openDialogs.length-1].elements.dialog.clientHeight <= document.documentElement.clientHeight){
                    topScroll = scrollY;
                    top = window.getComputedStyle(document.body).top;
                    addClass(document.body, classes.fixed);
                    document.body.style.top = -scrollY + 'px';
                } else if(!add) {
                    scrollY = topScroll;
                    document.body.style.top = top;
                    removeClass(document.body, classes.fixed);
                    restoreScrollPosition();
                }
            }
        }
		
        /**
         * Sets the name of the transition used to show/hide the dialog
         * 
         * @param {Object} instance The dilog instance.
         *
         */
        function updateTransition(instance, value, oldValue){
            if(typeof oldValue === 'string'){
                removeClass(instance.elements.root,classes.prefix +  oldValue);
            }
            addClass(instance.elements.root, classes.prefix + value);
            reflow = instance.elements.root.offsetWidth;
        }
		
        /**
         * Toggles the dialog display mode
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function updateDisplayMode(instance){
            if(instance.get('modal')){

                //make modal
                removeClass(instance.elements.root, classes.modeless);

                //only if open
                if(instance.isOpen()){
                    unbindModelessEvents(instance);

                    //in case a pinned modless dialog was made modal while open.
                    updateAbsPositionFix(instance);

                    ensureNoOverflow();
                }
            }else{
                //make modelss
                addClass(instance.elements.root, classes.modeless);

                //only if open
                if(instance.isOpen()){
                    bindModelessEvents(instance);

                    //in case pin/unpin was called while a modal is open
                    updateAbsPositionFix(instance);

                    ensureNoOverflow();
                }
            }
        }

        /**
         * Toggles the dialog basic view mode 
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function updateBasicMode(instance){
            if (instance.get('basic')) {
                // add class
                addClass(instance.elements.root, classes.basic);
            } else {
                // remove class
                removeClass(instance.elements.root, classes.basic);
            }
        }

        /**
         * Toggles the dialog frameless view mode 
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function updateFramelessMode(instance){
            if (instance.get('frameless')) {
                // add class
                addClass(instance.elements.root, classes.frameless);
            } else {
                // remove class
                removeClass(instance.elements.root, classes.frameless);
            }
        }
		
        /**
         * Helper: Brings the modeless dialog to front, attached to modeless dialogs.
         *
         * @param {Event} event Focus event
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bringToFront(event, instance){
            
            // Do not bring to front if preceeded by an open modal
            var index = openDialogs.indexOf(instance);
            for(var x=index+1;x<openDialogs.length;x+=1){
                if(openDialogs[x].isModal()){
                    return;
                }
            }
			
            // Bring to front by making it the last child.
            if(document.body.lastChild !== instance.elements.root){
                document.body.appendChild(instance.elements.root);
                //also make sure its at the end of the list
                openDialogs.splice(openDialogs.indexOf(instance),1);
                openDialogs.push(instance);
                setFocus(instance);
            }
			
            return false;
        }
		
        /**
         * Helper: reflects dialogs options updates
         *
         * @param {Object} instance The dilog instance.
         * @param {String} option The updated option name.
         *
         * @return	{undefined}	
         */
        function optionUpdated(instance, option, oldValue, newValue){
            switch(option){
            case 'title':
                instance.setHeader(newValue);
                break;
            case 'modal':
                updateDisplayMode(instance);
                break;
            case 'basic':
                updateBasicMode(instance);
                break;
            case 'frameless':
                updateFramelessMode(instance);
                break;
            case 'pinned':
                updatePinned(instance);
                break;
            case 'closable':
                updateClosable(instance);
                break;
            case 'maximizable':
                updateMaximizable(instance);
                break;
            case 'pinnable':
                updatePinnable(instance);
                break;
            case 'movable':
                updateMovable(instance);
                break;
            case 'resizable':
                updateResizable(instance);
                break;
            case 'padding':
                if(newValue){
                    removeClass(instance.elements.root, classes.noPadding);
                }else if(instance.elements.root.className.indexOf(classes.noPadding) < 0){
                    addClass(instance.elements.root, classes.noPadding);
                }
                break;
            case 'overflow':
                if(newValue){
                    removeClass(instance.elements.root, classes.noOverflow);
                }else if(instance.elements.root.className.indexOf(classes.noOverflow) < 0){
                    addClass(instance.elements.root, classes.noOverflow);
                }
                break;
            case 'transition':
                updateTransition(instance,newValue, oldValue);
                break;
            }

            // internal on option updated event
            if(typeof instance.hooks.onupdate === 'function'){
                instance.hooks.onupdate.call(instance, option, oldValue, newValue);
            }
        }
		
        /**
         * Helper: reflects dialogs options updates
         *
         * @param {Object} instance The dilog instance.
         * @param {Object} obj The object to set/get a value on/from.
         * @param {Function} callback The callback function to call if the key was found.
         * @param {String|Object} key A string specifying a propery name or a collection of key value pairs.
         * @param {Object} value Optional, the value associated with the key (in case it was a string).
         * @param {String} option The updated option name.
         *
         * @return	{Object} result object 
         *	The result objects has an 'op' property, indicating of this is a SET or GET operation.
         *		GET: 
         *		- found: a flag indicating if the key was found or not.
         *		- value: the property value.
         *		SET:
         *		- items: a list of key value pairs of the properties being set.
         *				each contains:
         *					- found: a flag indicating if the key was found or not.
         *					- key: the property key.
         *					- value: the property value.
         */
        function update(instance, obj, callback, key, value){
            var result = {op:undefined, items: [] };
            if(typeof value === 'undefined' && typeof key === 'string') {
                //get
                result.op = 'get';
                if(obj.hasOwnProperty(key)){
                    result.found = true;
                    result.value = obj[key];
                }else{
                    result.found = false;
                    result.value = undefined;
                }
            }
            else
            {
                var old;
                //set
                result.op = 'set';
                if(typeof key === 'object'){
                    //set multiple
                    var args = key;
                    for (var prop in args) {
                        if (obj.hasOwnProperty(prop)) {
                            if(obj[prop] !== args[prop]){
                                old = obj[prop];
                                obj[prop] = args[prop];
                                callback.call(instance,prop, old, args[prop]);
                            }
                            result.items.push({ 'key': prop, 'value': args[prop], 'found':true});
                        }else{
                            result.items.push({ 'key': prop, 'value': args[prop], 'found':false});
                        }
                    }
                } else if (typeof key === 'string'){
                    //set single
                    if (obj.hasOwnProperty(key)) {
                        if(obj[key] !== value){
                            old  = obj[key];
                            obj[key] = value;
                            callback.call(instance,key, old, value);
                        }
                        result.items.push({'key': key, 'value': value , 'found':true});

                    }else{
                        result.items.push({'key': key, 'value': value , 'found':false});
                    }
                } else {
                    //invalid params
                    throw new Error('args must be a string or object');
                }
            }
            return result;
        }


        /**
         * Triggers a close event.
         *
         * @param {Object} instance	The dilog instance.
         * 
         * @return {undefined}
         */
        function triggerClose(instance) {
            var found;
            triggerCallback(instance, function (button) {
                return found = (button.invokeOnClose === true);
            });
            //none of the buttons registered as onclose callback
            //close the dialog
            if (!found && instance.isOpen()) {
                instance.close();
            }
        }

        /**
         * Dialogs commands event handler, attached to the dialog commands element.
         *
         * @param {Event} event	DOM event object.
         * @param {Object} instance	The dilog instance.
         * 
         * @return {undefined}
         */
        function commandsClickHandler(event, instance) {
            var target = event.srcElement || event.target;
            switch (target) {
            case instance.elements.commands.pin:
                if (!instance.isPinned()) {
                    pin(instance);
                } else {
                    unpin(instance);
                }
                break;
            case instance.elements.commands.maximize:
                if (!instance.isMaximized()) {
                    maximize(instance);
                } else {
                    restore(instance);
                }
                break;
            case instance.elements.commands.close:
                triggerClose(instance);
                break;
            }
            return false;
        }

        /**
         * Helper: pins the modeless dialog.
         *
         * @param {Object} instance	The dialog instance.
         * 
         * @return {undefined}
         */
        function pin(instance) {
            //pin the dialog
            instance.set('pinned', true);
        }

        /**
         * Helper: unpins the modeless dialog.
         *
         * @param {Object} instance	The dilog instance.
         * 
         * @return {undefined}
         */
        function unpin(instance) {
            //unpin the dialog 
            instance.set('pinned', false);
        }


        /**
         * Helper: enlarges the dialog to fill the entire screen.
         *
         * @param {Object} instance	The dilog instance.
         * 
         * @return {undefined}
         */
        function maximize(instance) {
            // allow custom `onmaximize` method
            dispatchEvent('onmaximize', instance);
            //maximize the dialog 
            addClass(instance.elements.root, classes.maximized);
            if (instance.isOpen()) {
                ensureNoOverflow();
            }
            // allow custom `onmaximized` method
            dispatchEvent('onmaximized', instance);
        }

        /**
         * Helper: returns the dialog to its former size.
         *
         * @param {Object} instance	The dilog instance.
         * 
         * @return {undefined}
         */
        function restore(instance) {
            // allow custom `onrestore` method
            dispatchEvent('onrestore', instance);
            //maximize the dialog 
            removeClass(instance.elements.root, classes.maximized);
            if (instance.isOpen()) {
                ensureNoOverflow();
            }
            // allow custom `onrestored` method
            dispatchEvent('onrestored', instance);
        }

        /**
         * Show or hide the maximize box.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to add the behavior, removes it otherwise.
         *
         * @return {undefined}
         */
        function updatePinnable(instance) {
            if (instance.get('pinnable')) {
                // add class
                addClass(instance.elements.root, classes.pinnable);
            } else {
                // remove class
                removeClass(instance.elements.root, classes.pinnable);
            }
        }

        /**
         * Helper: Fixes the absolutly positioned modal div position.
         *
         * @param {Object} instance The dialog instance.
         *
         * @return {undefined}
         */
        function addAbsPositionFix(instance) {
            var scrollLeft = getScrollLeft();
            instance.elements.modal.style.marginTop = getScrollTop() + 'px';
            instance.elements.modal.style.marginLeft = scrollLeft + 'px';
            instance.elements.modal.style.marginRight = (-scrollLeft) + 'px';
        }

        /**
         * Helper: Removes the absolutly positioned modal div position fix.
         *
         * @param {Object} instance The dialog instance.
         *
         * @return {undefined}
         */
        function removeAbsPositionFix(instance) {
            var marginTop = parseInt(instance.elements.modal.style.marginTop, 10);
            var marginLeft = parseInt(instance.elements.modal.style.marginLeft, 10);
            instance.elements.modal.style.marginTop = '';
            instance.elements.modal.style.marginLeft = '';
            instance.elements.modal.style.marginRight = '';

            if (instance.isOpen()) {
                var top = 0,
                    left = 0
                ;
                if (instance.elements.dialog.style.top !== '') {
                    top = parseInt(instance.elements.dialog.style.top, 10);
                }
                instance.elements.dialog.style.top = (top + (marginTop - getScrollTop())) + 'px';

                if (instance.elements.dialog.style.left !== '') {
                    left = parseInt(instance.elements.dialog.style.left, 10);
                }
                instance.elements.dialog.style.left = (left + (marginLeft - getScrollLeft())) + 'px';
            }
        }
        /**
         * Helper: Adds/Removes the absolutly positioned modal div position fix based on its pinned setting.
         *
         * @param {Object} instance The dialog instance.
         *
         * @return {undefined}
         */
        function updateAbsPositionFix(instance) {
            // if modeless and unpinned add fix
            if (!instance.get('modal') && !instance.get('pinned')) {
                addAbsPositionFix(instance);
            } else {
                removeAbsPositionFix(instance);
            }
        }
        /**
         * Toggles the dialog position lock | modeless only.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to make it modal, false otherwise.
         *
         * @return {undefined}
         */
        function updatePinned(instance) {
            if (instance.get('pinned')) {
                removeClass(instance.elements.root, classes.unpinned);
                if (instance.isOpen()) {
                    removeAbsPositionFix(instance);
                }
            } else {
                addClass(instance.elements.root, classes.unpinned);
                if (instance.isOpen() && !instance.isModal()) {
                    addAbsPositionFix(instance);
                }
            }
        }

        /**
         * Show or hide the maximize box.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to add the behavior, removes it otherwise.
         *
         * @return {undefined}
         */
        function updateMaximizable(instance) {
            if (instance.get('maximizable')) {
                // add class
                addClass(instance.elements.root, classes.maximizable);
            } else {
                // remove class
                removeClass(instance.elements.root, classes.maximizable);
            }
        }

        /**
         * Show or hide the close box.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to add the behavior, removes it otherwise.
         *
         * @return {undefined}
         */
        function updateClosable(instance) {
            if (instance.get('closable')) {
                // add class
                addClass(instance.elements.root, classes.closable);
                bindClosableEvents(instance);
            } else {
                // remove class
                removeClass(instance.elements.root, classes.closable);
                unbindClosableEvents(instance);
            }
        }

        
        var cancelClick = false,// flag to cancel click event if already handled by end resize event (the mousedown, mousemove, mouseup sequence fires a click event.).
            modalClickHandlerTS=0 // stores last click timestamp to prevent executing the handler twice on double click.
            ;

        /**
         * Helper: closes the modal dialog when clicking the modal
         *
         * @param {Event} event	DOM event object.
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function modalClickHandler(event, instance) {
            if(event.timeStamp - modalClickHandlerTS > 200 && (modalClickHandlerTS = event.timeStamp) && !cancelClick){
                var target = event.srcElement || event.target;
                if (instance.get('closableByDimmer') === true && target === instance.elements.modal) {
                    triggerClose(instance);
                }
                cancelClick = false;
                return false;
            }
        }

        // stores last call timestamp to prevent triggering the callback twice.
        var callbackTS = 0;
        // flag to cancel keyup event if already handled by click event (pressing Enter on a focusted button).
        var cancelKeyup = false;
        /** 
         * Helper: triggers a button callback
         *
         * @param {Object}		The dilog instance.
         * @param {Function}	Callback to check which button triggered the event.
         *
         * @return {undefined}
         */
        function triggerCallback(instance, check) {
            if(Date.now() - callbackTS > 200 && (callbackTS = Date.now())){
                for (var idx = 0; idx < instance.__internal.buttons.length; idx += 1) {
                    var button = instance.__internal.buttons[idx];
                    if (!button.element.disabled && check(button)) {
                        var closeEvent = createCloseEvent(idx, button);
                        if (typeof instance.callback === 'function') {
                            instance.callback.apply(instance, [closeEvent]);
                        }
                        //close the dialog only if not canceled.
                        if (closeEvent.cancel === false) {
                            instance.close();
                        }
                        break;
                    }
                }
            }
        }

        /**
         * Clicks event handler, attached to the dialog footer.
         *
         * @param {Event}		DOM event object.
         * @param {Object}		The dilog instance.
         * 
         * @return {undefined}
         */
        function buttonsClickHandler(event, instance) {
            var target = event.srcElement || event.target;
            triggerCallback(instance, function (button) {
                // if this button caused the click, cancel keyup event
                return button.element === target && (cancelKeyup = true);
            });
        }

        /**
         * Keyup event handler, attached to the document.body
         *
         * @param {Event}		DOM event object.
         * @param {Object}		The dilog instance.
         * 
         * @return {undefined}
         */
        function keyupHandler(event) {
            //hitting enter while button has focus will trigger keyup too.
            //ignore if handled by clickHandler
            if (cancelKeyup) {
                cancelKeyup = false;
                return;
            }
            var instance = openDialogs[openDialogs.length - 1];
            var keyCode = event.keyCode;
            if (instance.__internal.buttons.length === 0 && keyCode === keys.ESC && instance.get('closable') === true) {
                triggerClose(instance);
                return false;
            }else if (usedKeys.indexOf(keyCode) > -1) {
                triggerCallback(instance, function (button) {
                    return button.key === keyCode;
                });
                return false;
            }
        }
        /**
        * Keydown event handler, attached to the document.body
        *
        * @param {Event}		DOM event object.
        * @param {Object}		The dilog instance.
        * 
        * @return {undefined}
        */
        function keydownHandler(event) {
            var instance = openDialogs[openDialogs.length - 1];
            var keyCode = event.keyCode;
            if (keyCode === keys.LEFT || keyCode === keys.RIGHT) {
                var buttons = instance.__internal.buttons;
                for (var x = 0; x < buttons.length; x += 1) {
                    if (document.activeElement === buttons[x].element) {
                        switch (keyCode) {
                        case keys.LEFT:
                            buttons[(x || buttons.length) - 1].element.focus();
                            return;
                        case keys.RIGHT:
                            buttons[(x + 1) % buttons.length].element.focus();
                            return;
                        }
                    }
                }
            }else if (keyCode < keys.F12 + 1 && keyCode > keys.F1 - 1 && usedKeys.indexOf(keyCode) > -1) {
                event.preventDefault();
                event.stopPropagation();
                triggerCallback(instance, function (button) {
                    return button.key === keyCode;
                });
                return false;
            }
        }


        /**
         * Sets focus to proper dialog element
         *
         * @param {Object} instance The dilog instance.
         * @param {Node} [resetTarget=undefined] DOM element to reset focus to.
         *
         * @return {undefined}
         */
        function setFocus(instance, resetTarget) {
            // reset target has already been determined.
            if (resetTarget) {
                resetTarget.focus();
            } else {
                // current instance focus settings
                var focus = instance.__internal.focus;
                // the focus element.
                var element = focus.element;

                switch (typeof focus.element) {
                // a number means a button index
                case 'number':
                    if (instance.__internal.buttons.length > focus.element) {
                        //in basic view, skip focusing the buttons.
                        if (instance.get('basic') === true) {
                            element = instance.elements.reset[0];
                        } else {
                            element = instance.__internal.buttons[focus.element].element;
                        }
                    }
                    break;
                // a string means querySelector to select from dialog body contents.
                case 'string':
                    element = instance.elements.body.querySelector(focus.element);
                    break;
                // a function should return the focus element.
                case 'function':
                    element = focus.element.call(instance);
                    break;
                }
                
                // if no focus element, default to first reset element.
                if ((typeof element === 'undefined' || element === null) && instance.__internal.buttons.length === 0) {
                    element = instance.elements.reset[0];
                }
                // focus
                if (element && element.focus) {
                    element.focus();
                    // if selectable
                    if (focus.select && element.select) {
                        element.select();
                    }
                }
            }
        }

        /**
         * Focus event handler, attached to document.body and dialogs own reset links.
         * handles the focus for modal dialogs only.
         *
         * @param {Event} event DOM focus event object.
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function onReset(event, instance) {

            // should work on last modal if triggered from document.body 
            if (!instance) {
                for (var x = openDialogs.length - 1; x > -1; x -= 1) {
                    if (openDialogs[x].isModal()) {
                        instance = openDialogs[x];
                        break;
                    }
                }
            }
            // if modal
            if (instance && instance.isModal()) {
                // determine reset target to enable forward/backward tab cycle.
                var resetTarget, target = event.srcElement || event.target;
                var lastResetElement = target === instance.elements.reset[1] || (instance.__internal.buttons.length === 0 && target === document.body);

                // if last reset link, then go to maximize or close
                if (lastResetElement) {
                    if (instance.get('maximizable')) {
                        resetTarget = instance.elements.commands.maximize;
                    } else if (instance.get('closable')) {
                        resetTarget = instance.elements.commands.close;
                    }
                }
                // if no reset target found, try finding the best button
                if (resetTarget === undefined) {
                    if (typeof instance.__internal.focus.element === 'number') {
                        // button focus element, go to first available button
                        if (target === instance.elements.reset[0]) {
                            resetTarget = instance.elements.buttons.auxiliary.firstChild || instance.elements.buttons.primary.firstChild;
                        } else if (lastResetElement) {
                            //restart the cycle by going to first reset link
                            resetTarget = instance.elements.reset[0];
                        }
                    } else {
                        // will reach here when tapping backwards, so go to last child
                        // The focus element SHOULD NOT be a button (logically!).
                        if (target === instance.elements.reset[0]) {
                            resetTarget = instance.elements.buttons.primary.lastChild || instance.elements.buttons.auxiliary.lastChild;
                        }
                    }
                }
                // focus
                setFocus(instance, resetTarget);
            }
        }
        /**
         * Transition in transitionend event handler. 
         *
         * @param {Event}		TransitionEnd event object.
         * @param {Object}		The dilog instance.
         *
         * @return {undefined}
         */
        function handleTransitionInEvent(event, instance) {
            // clear the timer
            clearTimeout(instance.__internal.timerIn);

            // once transition is complete, set focus
            setFocus(instance);

            //restore scroll to prevent document jump
            restoreScrollPosition();

            // allow handling key up after transition ended.
            cancelKeyup = false;

            // allow custom `onfocus` method
            dispatchEvent('onfocus', instance);

            // unbind the event
            off(instance.elements.dialog, transition.type, instance.__internal.transitionInHandler);

            removeClass(instance.elements.root, classes.animationIn);
        }

        /**
         * Transition out transitionend event handler. 
         *
         * @param {Event}		TransitionEnd event object.
         * @param {Object}		The dilog instance.
         *
         * @return {undefined}
         */
        function handleTransitionOutEvent(event, instance) {
            // clear the timer
            clearTimeout(instance.__internal.timerOut);
            // unbind the event
            off(instance.elements.dialog, transition.type, instance.__internal.transitionOutHandler);

            // reset move updates
            resetMove(instance);
            // reset resize updates
            resetResize(instance);

            // restore if maximized
            if (instance.isMaximized() && !instance.get('startMaximized')) {
                restore(instance);
            }

            // return focus to the last active element
            if (alertify.defaults.maintainFocus && instance.__internal.activeElement) {
                instance.__internal.activeElement.focus();
                instance.__internal.activeElement = null;
            }
            
            //destory the instance
            if (typeof instance.__internal.destroy === 'function') {
                instance.__internal.destroy.apply(instance);
            }
        }
        /* Controls moving a dialog around */
        //holde the current moving instance
        var movable = null,
            //holds the current X offset when move starts
            offsetX = 0,
            //holds the current Y offset when move starts
            offsetY = 0,
            xProp = 'pageX',
            yProp = 'pageY',
            bounds = null,
            refreshTop = false,
            moveDelegate = null
        ;

        /**
         * Helper: sets the element top/left coordinates
         *
         * @param {Event} event	DOM event object.
         * @param {Node} element The element being moved.
         * 
         * @return {undefined}
         */
        function moveElement(event, element) {
            var left = (event[xProp] - offsetX),
                top  = (event[yProp] - offsetY);

            if(refreshTop){
                top -= document.body.scrollTop;
            }
           
            element.style.left = left + 'px';
            element.style.top = top + 'px';
           
        }
        /**
         * Helper: sets the element top/left coordinates within screen bounds
         *
         * @param {Event} event	DOM event object.
         * @param {Node} element The element being moved.
         * 
         * @return {undefined}
         */
        function moveElementBounded(event, element) {
            var left = (event[xProp] - offsetX),
                top  = (event[yProp] - offsetY);

            if(refreshTop){
                top -= document.body.scrollTop;
            }
            
            element.style.left = Math.min(bounds.maxLeft, Math.max(bounds.minLeft, left)) + 'px';
            if(refreshTop){
                element.style.top = Math.min(bounds.maxTop, Math.max(bounds.minTop, top)) + 'px';
            }else{
                element.style.top = Math.max(bounds.minTop, top) + 'px';
            }
        }
            

        /**
         * Triggers the start of a move event, attached to the header element mouse down event.
         * Adds no-selection class to the body, disabling selection while moving.
         *
         * @param {Event} event	DOM event object.
         * @param {Object} instance The dilog instance.
         * 
         * @return {Boolean} false
         */
        function beginMove(event, instance) {
            if (resizable === null && !instance.isMaximized() && instance.get('movable')) {
                var eventSrc, left=0, top=0;
                if (event.type === 'touchstart') {
                    event.preventDefault();
                    eventSrc = event.targetTouches[0];
                    xProp = 'clientX';
                    yProp = 'clientY';
                } else if (event.button === 0) {
                    eventSrc = event;
                }

                if (eventSrc) {

                    var element = instance.elements.dialog;
                    addClass(element, classes.capture);

                    if (element.style.left) {
                        left = parseInt(element.style.left, 10);
                    }

                    if (element.style.top) {
                        top = parseInt(element.style.top, 10);
                    }
                    
                    offsetX = eventSrc[xProp] - left;
                    offsetY = eventSrc[yProp] - top;

                    if(instance.isModal()){
                        offsetY += instance.elements.modal.scrollTop;
                    }else if(instance.isPinned()){
                        offsetY -= document.body.scrollTop;
                    }
                    
                    if(instance.get('moveBounded')){
                        var current = element,
                            offsetLeft = -left,
                            offsetTop = -top;
                        
                        //calc offset
                        do {
                            offsetLeft += current.offsetLeft;
                            offsetTop += current.offsetTop;
                        } while (current = current.offsetParent);
                        
                        bounds = {
                            maxLeft : offsetLeft,
                            minLeft : -offsetLeft,
                            maxTop  : document.documentElement.clientHeight - element.clientHeight - offsetTop,
                            minTop  : -offsetTop
                        };
                        moveDelegate = moveElementBounded;
                    }else{
                        bounds = null;
                        moveDelegate = moveElement;
                    }
                    
                    // allow custom `onmove` method
                    dispatchEvent('onmove', instance);

                    refreshTop = !instance.isModal() && instance.isPinned();
                    movable = instance;
                    moveDelegate(eventSrc, element);
                    addClass(document.body, classes.noSelection);
                    return false;
                }
            }
        }

        /**
         * The actual move handler,  attached to document.body mousemove event.
         *
         * @param {Event} event	DOM event object.
         * 
         * @return {undefined}
         */
        function move(event) {
            if (movable) {
                var eventSrc;
                if (event.type === 'touchmove') {
                    event.preventDefault();
                    eventSrc = event.targetTouches[0];
                } else if (event.button === 0) {
                    eventSrc = event;
                }
                if (eventSrc) {
                    moveDelegate(eventSrc, movable.elements.dialog);
                }
            }
        }

        /**
         * Triggers the end of a move event,  attached to document.body mouseup event.
         * Removes no-selection class from document.body, allowing selection.
         *
         * @return {undefined}
         */
        function endMove() {
            if (movable) {
                var instance = movable;
                movable = bounds = null;
                removeClass(document.body, classes.noSelection);
                removeClass(instance.elements.dialog, classes.capture);
                // allow custom `onmoved` method
                dispatchEvent('onmoved', instance);
            }
        }

        /**
         * Resets any changes made by moving the element to its original state,
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function resetMove(instance) {
            movable = null;
            var element = instance.elements.dialog;
            element.style.left = element.style.top = '';
        }

        /**
         * Updates the dialog move behavior.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to add the behavior, removes it otherwise.
         *
         * @return {undefined}
         */
        function updateMovable(instance) {
            if (instance.get('movable')) {
                // add class
                addClass(instance.elements.root, classes.movable);
                if (instance.isOpen()) {
                    bindMovableEvents(instance);
                }
            } else {

                //reset
                resetMove(instance);
                // remove class
                removeClass(instance.elements.root, classes.movable);
                if (instance.isOpen()) {
                    unbindMovableEvents(instance);
                }
            }
        }

        /* Controls moving a dialog around */
        //holde the current instance being resized		
        var resizable = null,
            //holds the staring left offset when resize starts.
            startingLeft = Number.Nan,
            //holds the staring width when resize starts.
            startingWidth = 0,
            //holds the initial width when resized for the first time.
            minWidth = 0,
            //holds the offset of the resize handle.
            handleOffset = 0
        ;

        /**
         * Helper: sets the element width/height and updates left coordinate if neccessary.
         *
         * @param {Event} event	DOM mousemove event object.
         * @param {Node} element The element being moved.
         * @param {Boolean} pinned A flag indicating if the element being resized is pinned to the screen.
         * 
         * @return {undefined}
         */
        function resizeElement(event, element, pageRelative) {

            //calculate offsets from 0,0
            var current = element;
            var offsetLeft = 0;
            var offsetTop = 0;
            do {
                offsetLeft += current.offsetLeft;
                offsetTop += current.offsetTop;
            } while (current = current.offsetParent);

            // determine X,Y coordinates.
            var X, Y;
            if (pageRelative === true) {
                X = event.pageX;
                Y = event.pageY;
            } else {
                X = event.clientX;
                Y = event.clientY;
            }
            // rtl handling
            var isRTL = isRightToLeft();
            if (isRTL) {
                // reverse X 
                X = document.body.offsetWidth - X;
                // if has a starting left, calculate offsetRight
                if (!isNaN(startingLeft)) {
                    offsetLeft = document.body.offsetWidth - offsetLeft - element.offsetWidth;
                }
            }

            // set width/height
            element.style.height = (Y - offsetTop + handleOffset) + 'px';
            element.style.width = (X - offsetLeft + handleOffset) + 'px';

            // if the element being resized has a starting left, maintain it.
            // the dialog is centered, divide by half the offset to maintain the margins.
            if (!isNaN(startingLeft)) {
                var diff = Math.abs(element.offsetWidth - startingWidth) * 0.5;
                if (isRTL) {
                    //negate the diff, why?
                    //when growing it should decrease left
                    //when shrinking it should increase left
                    diff *= -1;
                }
                if (element.offsetWidth > startingWidth) {
                    //growing
                    element.style.left = (startingLeft + diff) + 'px';
                } else if (element.offsetWidth >= minWidth) {
                    //shrinking
                    element.style.left = (startingLeft - diff) + 'px';
                }
            }
        }

        /**
         * Triggers the start of a resize event, attached to the resize handle element mouse down event.
         * Adds no-selection class to the body, disabling selection while moving.
         *
         * @param {Event} event	DOM event object.
         * @param {Object} instance The dilog instance.
         * 
         * @return {Boolean} false
         */
        function beginResize(event, instance) {
            if (!instance.isMaximized()) {
                var eventSrc;
                if (event.type === 'touchstart') {
                    event.preventDefault();
                    eventSrc = event.targetTouches[0];
                } else if (event.button === 0) {
                    eventSrc = event;
                }
                if (eventSrc) {
                    // allow custom `onresize` method
                    dispatchEvent('onresize', instance);
                    
                    resizable = instance;
                    handleOffset = instance.elements.resizeHandle.offsetHeight / 2;
                    var element = instance.elements.dialog;
                    addClass(element, classes.capture);
                    startingLeft = parseInt(element.style.left, 10);
                    element.style.height = element.offsetHeight + 'px';
                    element.style.minHeight = instance.elements.header.offsetHeight + instance.elements.footer.offsetHeight + 'px';
                    element.style.width = (startingWidth = element.offsetWidth) + 'px';

                    if (element.style.maxWidth !== 'none') {
                        element.style.minWidth = (minWidth = element.offsetWidth) + 'px';
                    }
                    element.style.maxWidth = 'none';
                    addClass(document.body, classes.noSelection);
                    return false;
                }
            }
        }

        /**
         * The actual resize handler,  attached to document.body mousemove event.
         *
         * @param {Event} event	DOM event object.
         * 
         * @return {undefined}
         */
        function resize(event) {
            if (resizable) {
                var eventSrc;
                if (event.type === 'touchmove') {
                    event.preventDefault();
                    eventSrc = event.targetTouches[0];
                } else if (event.button === 0) {
                    eventSrc = event;
                }
                if (eventSrc) {
                    resizeElement(eventSrc, resizable.elements.dialog, !resizable.get('modal') && !resizable.get('pinned'));
                }
            }
        }

        /**
         * Triggers the end of a resize event,  attached to document.body mouseup event.
         * Removes no-selection class from document.body, allowing selection.
         *
         * @return {undefined}
         */
        function endResize() {
            if (resizable) {
                var instance = resizable;
                resizable = null;
                removeClass(document.body, classes.noSelection);
                removeClass(instance.elements.dialog, classes.capture);
                cancelClick = true;
                // allow custom `onresized` method
                dispatchEvent('onresized', instance);
            }
        }

        /**
         * Resets any changes made by resizing the element to its original state.
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function resetResize(instance) {
            resizable = null;
            var element = instance.elements.dialog;
            if (element.style.maxWidth === 'none') {
                //clear inline styles.
                element.style.maxWidth = element.style.minWidth = element.style.width = element.style.height = element.style.minHeight = element.style.left = '';
                //reset variables.
                startingLeft = Number.Nan;
                startingWidth = minWidth = handleOffset = 0;
            }
        }


        /**
         * Updates the dialog move behavior.
         *
         * @param {Object} instance The dilog instance.
         * @param {Boolean} on True to add the behavior, removes it otherwise.
         *
         * @return {undefined}
         */
        function updateResizable(instance) {
            if (instance.get('resizable')) {
                // add class
                addClass(instance.elements.root, classes.resizable);
                if (instance.isOpen()) {
                    bindResizableEvents(instance);
                }
            } else {
                //reset
                resetResize(instance);
                // remove class
                removeClass(instance.elements.root, classes.resizable);
                if (instance.isOpen()) {
                    unbindResizableEvents(instance);
                }
            }
        }

        /**
         * Reset move/resize on window resize.
         *
         * @param {Event} event	window resize event object.
         *
         * @return {undefined}
         */
        function windowResize(/*event*/) {
            for (var x = 0; x < openDialogs.length; x += 1) {
                var instance = openDialogs[x];
                if (instance.get('autoReset')) {
                    resetMove(instance);
                    resetResize(instance);
                }
            }
        }
        /**
         * Bind dialogs events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bindEvents(instance) {
            // if first dialog, hook global handlers
            if (openDialogs.length === 1) {
                //global
                on(window, 'resize', windowResize);
                on(document.body, 'keyup', keyupHandler);
                on(document.body, 'keydown', keydownHandler);
                on(document.body, 'focus', onReset);

                //move
                on(document.documentElement, 'mousemove', move);
                on(document.documentElement, 'touchmove', move);
                on(document.documentElement, 'mouseup', endMove);
                on(document.documentElement, 'touchend', endMove);
                //resize
                on(document.documentElement, 'mousemove', resize);
                on(document.documentElement, 'touchmove', resize);
                on(document.documentElement, 'mouseup', endResize);
                on(document.documentElement, 'touchend', endResize);
            }

            // common events
            on(instance.elements.commands.container, 'click', instance.__internal.commandsClickHandler);
            on(instance.elements.footer, 'click', instance.__internal.buttonsClickHandler);
            on(instance.elements.reset[0], 'focus', instance.__internal.resetHandler);
            on(instance.elements.reset[1], 'focus', instance.__internal.resetHandler);

            //prevent handling key up when dialog is being opened by a key stroke.
            cancelKeyup = true;
            // hook in transition handler
            on(instance.elements.dialog, transition.type, instance.__internal.transitionInHandler);

            // modelss only events
            if (!instance.get('modal')) {
                bindModelessEvents(instance);
            }

            // resizable
            if (instance.get('resizable')) {
                bindResizableEvents(instance);
            }

            // movable
            if (instance.get('movable')) {
                bindMovableEvents(instance);
            }
        }

        /**
         * Unbind dialogs events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function unbindEvents(instance) {
            // if last dialog, remove global handlers
            if (openDialogs.length === 1) {
                //global
                off(window, 'resize', windowResize);
                off(document.body, 'keyup', keyupHandler);
                off(document.body, 'keydown', keydownHandler);
                off(document.body, 'focus', onReset);
                //move
                off(document.documentElement, 'mousemove', move);
                off(document.documentElement, 'mouseup', endMove);
                //resize
                off(document.documentElement, 'mousemove', resize);
                off(document.documentElement, 'mouseup', endResize);
            }

            // common events
            off(instance.elements.commands.container, 'click', instance.__internal.commandsClickHandler);
            off(instance.elements.footer, 'click', instance.__internal.buttonsClickHandler);
            off(instance.elements.reset[0], 'focus', instance.__internal.resetHandler);
            off(instance.elements.reset[1], 'focus', instance.__internal.resetHandler);

            // hook out transition handler
            on(instance.elements.dialog, transition.type, instance.__internal.transitionOutHandler);

            // modelss only events
            if (!instance.get('modal')) {
                unbindModelessEvents(instance);
            }

            // movable
            if (instance.get('movable')) {
                unbindMovableEvents(instance);
            }

            // resizable
            if (instance.get('resizable')) {
                unbindResizableEvents(instance);
            }

        }

        /**
         * Bind modeless specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bindModelessEvents(instance) {
            on(instance.elements.dialog, 'focus', instance.__internal.bringToFrontHandler, true);
        }

        /**
         * Unbind modeless specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function unbindModelessEvents(instance) {
            off(instance.elements.dialog, 'focus', instance.__internal.bringToFrontHandler, true);
        }



        /**
         * Bind movable specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bindMovableEvents(instance) {
            on(instance.elements.header, 'mousedown', instance.__internal.beginMoveHandler);
            on(instance.elements.header, 'touchstart', instance.__internal.beginMoveHandler);
        }

        /**
         * Unbind movable specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function unbindMovableEvents(instance) {
            off(instance.elements.header, 'mousedown', instance.__internal.beginMoveHandler);
            off(instance.elements.header, 'touchstart', instance.__internal.beginMoveHandler);
        }



        /**
         * Bind resizable specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bindResizableEvents(instance) {
            on(instance.elements.resizeHandle, 'mousedown', instance.__internal.beginResizeHandler);
            on(instance.elements.resizeHandle, 'touchstart', instance.__internal.beginResizeHandler);
        }

        /**
         * Unbind resizable specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function unbindResizableEvents(instance) {
            off(instance.elements.resizeHandle, 'mousedown', instance.__internal.beginResizeHandler);
            off(instance.elements.resizeHandle, 'touchstart', instance.__internal.beginResizeHandler);
        }

        /**
         * Bind closable events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function bindClosableEvents(instance) {
            on(instance.elements.modal, 'click', instance.__internal.modalClickHandler);
        }

        /**
         * Unbind closable specific events
         *
         * @param {Object} instance The dilog instance.
         *
         * @return {undefined}
         */
        function unbindClosableEvents(instance) {
            off(instance.elements.modal, 'click', instance.__internal.modalClickHandler);
        }
        // dialog API
        return {
            __init:initialize,
            /**
             * Check if dialog is currently open
             *
             * @return {Boolean}
             */
            isOpen: function () {
                return this.__internal.isOpen;
            },
            isModal: function (){
                return this.elements.root.className.indexOf(classes.modeless) < 0;
            },
            isMaximized:function(){
                return this.elements.root.className.indexOf(classes.maximized) > -1;
            },
            isPinned:function(){
                return this.elements.root.className.indexOf(classes.unpinned) < 0;
            },
            maximize:function(){
                if(!this.isMaximized()){
                    maximize(this);
                }
                return this;
            },
            restore:function(){
                if(this.isMaximized()){
                    restore(this);
                }
                return this;
            },
            pin:function(){
                if(!this.isPinned()){
                    pin(this);
                }
                return this;
            },
            unpin:function(){
                if(this.isPinned()){
                    unpin(this);
                }
                return this;
            },
            bringToFront:function(){
                bringToFront(null, this);
                return this;
            },
            /**
             * Move the dialog to a specific x/y coordinates
             *
             * @param {Number} x    The new dialog x coordinate in pixels.
             * @param {Number} y    The new dialog y coordinate in pixels.
             *
             * @return {Object} The dialog instance.
             */
            moveTo:function(x,y){
                if(!isNaN(x) && !isNaN(y)){
                    // allow custom `onmove` method
                    dispatchEvent('onmove', this);
                    
                    var element = this.elements.dialog,
                        current = element,
                        offsetLeft = 0,
                        offsetTop = 0;
                    
                    //subtract existing left,top
                    if (element.style.left) {
                        offsetLeft -= parseInt(element.style.left, 10);
                    }
                    if (element.style.top) {
                        offsetTop -= parseInt(element.style.top, 10);
                    }
                    //calc offset
                    do {
                        offsetLeft += current.offsetLeft;
                        offsetTop += current.offsetTop;
                    } while (current = current.offsetParent);

                    //calc left, top
                    var left = (x - offsetLeft);
                    var top  = (y - offsetTop);

                    //// rtl handling
                    if (isRightToLeft()) {
                        left *= -1;
                    }

                    element.style.left = left + 'px';
                    element.style.top = top + 'px';
                    
                    // allow custom `onmoved` method
                    dispatchEvent('onmoved', this);
                }
                return this;
            },
            /**
             * Resize the dialog to a specific width/height (the dialog must be 'resizable').
             * The dialog can be resized to:
             *  A minimum width equal to the initial display width
             *  A minimum height equal to the sum of header/footer heights.
             *
             *
             * @param {Number or String} width    The new dialog width in pixels or in percent.
             * @param {Number or String} height   The new dialog height in pixels or in percent.
             *
             * @return {Object} The dialog instance.
             */
            resizeTo:function(width,height){
                var w = parseFloat(width),
                    h = parseFloat(height),
                    regex = /(\d*\.\d+|\d+)%/
                ;

                if(!isNaN(w) && !isNaN(h) && this.get('resizable') === true){
                    
                    // allow custom `onresize` method
                    dispatchEvent('onresize', this);
                    
                    if(('' + width).match(regex)){
                        w = w / 100 * document.documentElement.clientWidth ;
                    }

                    if(('' + height).match(regex)){
                        h = h / 100 * document.documentElement.clientHeight;
                    }

                    var element = this.elements.dialog;
                    if (element.style.maxWidth !== 'none') {
                        element.style.minWidth = (minWidth = element.offsetWidth) + 'px';
                    }
                    element.style.maxWidth = 'none';
                    element.style.minHeight = this.elements.header.offsetHeight + this.elements.footer.offsetHeight + 'px';
                    element.style.width = w + 'px';
                    element.style.height = h + 'px';
                    
                    // allow custom `onresized` method
                    dispatchEvent('onresized', this);
                }
                return this;
            },
            /**
             * Gets or Sets dialog settings/options 
             *
             * @param {String|Object} key A string specifying a propery name or a collection of key/value pairs.
             * @param {Object} value Optional, the value associated with the key (in case it was a string).
             *
             * @return {undefined}
             */
            setting : function (key, value) {
                var self = this;
                var result = update(this, this.__internal.options, function(k,o,n){ optionUpdated(self,k,o,n); }, key, value);
                if(result.op === 'get'){
                    if(result.found){
                        return result.value;
                    }else if(typeof this.settings !== 'undefined'){
                        return update(this, this.settings, this.settingUpdated || function(){}, key, value).value;
                    }else{
                        return undefined;
                    }
                }else if(result.op === 'set'){
                    if(result.items.length > 0){
                        var callback = this.settingUpdated || function(){};
                        for(var x=0;x<result.items.length;x+=1){
                            var item = result.items[x];
                            if(!item.found && typeof this.settings !== 'undefined'){
                                update(this, this.settings, callback, item.key, item.value);
                            }
                        }
                    }
                    return this;
                }
            },
            /**
             * [Alias] Sets dialog settings/options 
             */
            set:function(key, value){
                this.setting(key,value);
                return this;
            },
            /**
             * [Alias] Gets dialog settings/options 
             */
            get:function(key){
                return this.setting(key);
            },
            /**
            * Sets dialog header
            * @content {string or element}
            *
            * @return {undefined}
            */
            setHeader:function(content){
                if(typeof content === 'string'){
                    clearContents(this.elements.header);
                    this.elements.header.innerHTML = content;
                }else if (content instanceof window.HTMLElement && this.elements.header.firstChild !== content){
                    clearContents(this.elements.header);
                    this.elements.header.appendChild(content);
                }
                return this;
            },
            /**
            * Sets dialog contents
            * @content {string or element}
            *
            * @return {undefined}
            */
            setContent:function(content){
                if(typeof content === 'string'){
                    clearContents(this.elements.content);
                    this.elements.content.innerHTML = content;
                }else if (content instanceof window.HTMLElement && this.elements.content.firstChild !== content){
                    clearContents(this.elements.content);
                    this.elements.content.appendChild(content);
                }
                return this;
            },
            /**
             * Show the dialog as modal
             *
             * @return {Object} the dialog instance.
             */
            showModal: function(className){
                return this.show(true, className);
            },
            /**
             * Show the dialog
             *
             * @return {Object} the dialog instance.
             */
            show: function (modal, className) {
                
                // ensure initialization
                initialize(this);

                if ( !this.__internal.isOpen ) {

                    // add to open dialogs
                    this.__internal.isOpen = true;
                    openDialogs.push(this);

                    // save last focused element
                    if(alertify.defaults.maintainFocus){
                        this.__internal.activeElement = document.activeElement;
                    }

                    // set tabindex attribute on body element this allows script to give it focusable
                    if(!document.body.hasAttribute('tabindex')) {
                        document.body.setAttribute( 'tabindex', tabindex = '0');
                    }

                    //allow custom dom manipulation updates before showing the dialog.
                    if(typeof this.prepare === 'function'){
                        this.prepare();
                    }

                    bindEvents(this);

                    if(modal !== undefined){
                        this.set('modal', modal);
                    }

                    //save scroll to prevent document jump
                    saveScrollPosition();

                    ensureNoOverflow();

                    // allow custom dialog class on show
                    if(typeof className === 'string' && className !== ''){
                        this.__internal.className = className;
                        addClass(this.elements.root, className);
                    }

                    // maximize if start maximized
                    if ( this.get('startMaximized')) {
                        this.maximize();
                    }else if(this.isMaximized()){
                        restore(this);
                    }

                    updateAbsPositionFix(this);
                    this.elements.root.removeAttribute('style');
                    removeClass(this.elements.root, classes.animationOut);
                    addClass(this.elements.root, classes.animationIn);

                    // set 1s fallback in case transition event doesn't fire
                    clearTimeout( this.__internal.timerIn);
                    this.__internal.timerIn = setTimeout( this.__internal.transitionInHandler, transition.supported ? 1000 : 100 );

                    if(isSafari){
                        // force desktop safari reflow
                        var root = this.elements.root;
                        root.style.display  = 'none';
                        setTimeout(function(){root.style.display  = 'block';}, 0);
                    }

                    //reflow
                    reflow = this.elements.root.offsetWidth;
                  
                    // show dialog
                    removeClass(this.elements.root, classes.hidden);

                    // internal on show event
                    if(typeof this.hooks.onshow === 'function'){
                        this.hooks.onshow.call(this);
                    }

                    // allow custom `onshow` method
                    dispatchEvent('onshow', this);

                }else{
                    // reset move updates
                    resetMove(this);
                    // reset resize updates
                    resetResize(this);
                    // shake the dialog to indicate its already open
                    addClass(this.elements.dialog, classes.shake);
                    var self = this;
                    setTimeout(function(){
                        removeClass(self.elements.dialog, classes.shake);
                    },200);
                }
                return this;
            },
            /**
             * Close the dialog
             *
             * @return {Object} The dialog instance
             */
            close: function () {
                if (this.__internal.isOpen ) {
                    // custom `onclosing` event
                    if(dispatchEvent('onclosing', this) !== false){

                        unbindEvents(this);

                        removeClass(this.elements.root, classes.animationIn);
                        addClass(this.elements.root, classes.animationOut);

                        // set 1s fallback in case transition event doesn't fire
                        clearTimeout( this.__internal.timerOut );
                        this.__internal.timerOut = setTimeout( this.__internal.transitionOutHandler, transition.supported ? 1000 : 100 );
                        // hide dialog
                        addClass(this.elements.root, classes.hidden);
                        //reflow
                        reflow = this.elements.modal.offsetWidth;

                        // remove custom dialog class on hide
                        if (typeof this.__internal.className !== 'undefined' && this.__internal.className !== '') {
                            removeClass(this.elements.root, this.__internal.className);
                        }

                        // internal on close event
                        if(typeof this.hooks.onclose === 'function'){
                            this.hooks.onclose.call(this);
                        }

                        // allow custom `onclose` method
                        dispatchEvent('onclose', this);

                        //remove from open dialogs
                        openDialogs.splice(openDialogs.indexOf(this),1);
                        this.__internal.isOpen = false;

                        ensureNoOverflow();
                    }

                }
                // last dialog and tab index was set by us, remove it.
                if(!openDialogs.length && tabindex === '0'){
                    document.body.removeAttribute('tabindex');
                }
                return this;
            },
            /**
             * Close all open dialogs except this.
             *
             * @return {undefined}
             */
            closeOthers:function(){
                alertify.closeAll(this);
                return this;
            },
            /**
             * Destroys this dialog instance
             *
             * @return {undefined}
             */
            destroy:function(){
                if(this.__internal) {
                    if (this.__internal.isOpen ) {
                        //mark dialog for destruction, this will be called on tranistionOut event.
                        this.__internal.destroy = function(){
                            destruct(this, initialize);
                        };
                        //close the dialog to unbind all events.
                        this.close();
                    }else if(!this.__internal.destroy){
                        destruct(this, initialize);
                    }
                }
                return this;
            },
        };
	} () );
    var notifier = (function () {
        var reflow,
            element,
            openInstances = [],
            classes = {
                base: 'alertify-notifier',
                message: 'ajs-message',
                top: 'ajs-top',
                right: 'ajs-right',
                bottom: 'ajs-bottom',
                left: 'ajs-left',
                center: 'ajs-center',
                visible: 'ajs-visible',
                hidden: 'ajs-hidden',
                close: 'ajs-close'
            };
        /**
         * Helper: initializes the notifier instance
         *
         */
        function initialize(instance) {

            if (!instance.__internal) {
                instance.__internal = {
                    position: alertify.defaults.notifier.position,
                    delay: alertify.defaults.notifier.delay,
                };

                element = document.createElement('DIV');

                updatePosition(instance);
            }

            //add to DOM tree.
            if (element.parentNode !== document.body) {
                document.body.appendChild(element);
            }
        }

        function pushInstance(instance) {
            instance.__internal.pushed = true;
            openInstances.push(instance);
        }
        function popInstance(instance) {
            openInstances.splice(openInstances.indexOf(instance), 1);
            instance.__internal.pushed = false;
        }
        /**
         * Helper: update the notifier instance position
         *
         */
        function updatePosition(instance) {
            element.className = classes.base;
            switch (instance.__internal.position) {
            case 'top-right':
                addClass(element, classes.top + ' ' + classes.right);
                break;
            case 'top-left':
                addClass(element, classes.top + ' ' + classes.left);
                break;
            case 'top-center':
                addClass(element, classes.top + ' ' + classes.center);
                break;
            case 'bottom-left':
                addClass(element, classes.bottom + ' ' + classes.left);
                break;
            case 'bottom-center':
                addClass(element, classes.bottom + ' ' + classes.center);
                break;

            default:
            case 'bottom-right':
                addClass(element, classes.bottom + ' ' + classes.right);
                break;
            }
        }

        /**
        * creates a new notification message
        *
        * @param  {DOMElement} message	The notifier message element
        * @param  {Number} wait   Time (in ms) to wait before the message is dismissed, a value of 0 means keep open till clicked.
        * @param  {Function} callback A callback function to be invoked when the message is dismissed.
        *
        * @return {undefined}
        */
        function create(div, callback) {

            function clickDelegate(event, instance) {
                if(!instance.__internal.closeButton || event.target.getAttribute('data-close') === 'true'){
                    instance.dismiss(true);
                }
            }

            function transitionDone(event, instance) {
                // unbind event
                off(instance.element, transition.type, transitionDone);
                // remove the message
                element.removeChild(instance.element);
            }

            function initialize(instance) {
                if (!instance.__internal) {
                    instance.__internal = {
                        pushed: false,
                        delay : undefined,
                        timer: undefined,
                        clickHandler: undefined,
                        transitionEndHandler: undefined,
                        transitionTimeout: undefined
                    };
                    instance.__internal.clickHandler = delegate(instance, clickDelegate);
                    instance.__internal.transitionEndHandler = delegate(instance, transitionDone);
                }
                return instance;
            }
            function clearTimers(instance) {
                clearTimeout(instance.__internal.timer);
                clearTimeout(instance.__internal.transitionTimeout);
            }
            return initialize({
                /* notification DOM element*/
                element: div,
                /*
                 * Pushes a notification message
                 * @param {string or DOMElement} content The notification message content
                 * @param {Number} wait The time (in seconds) to wait before the message is dismissed, a value of 0 means keep open till clicked.
                 *
                 */
                push: function (_content, _wait) {
                    if (!this.__internal.pushed) {

                        pushInstance(this);
                        clearTimers(this);

                        var content, wait;
                        switch (arguments.length) {
                        case 0:
                            wait = this.__internal.delay;
                            break;
                        case 1:
                            if (typeof (_content) === 'number') {
                                wait = _content;
                            } else {
                                content = _content;
                                wait = this.__internal.delay;
                            }
                            break;
                        case 2:
                            content = _content;
                            wait = _wait;
                            break;
                        }
                        this.__internal.closeButton = alertify.defaults.notifier.closeButton;
                        // set contents
                        if (typeof content !== 'undefined') {
                            this.setContent(content);
                        }
                        // append or insert
                        if (notifier.__internal.position.indexOf('top') < 0) {
                            element.appendChild(this.element);
                        } else {
                            element.insertBefore(this.element, element.firstChild);
                        }
                        reflow = this.element.offsetWidth;
                        addClass(this.element, classes.visible);
                        // attach click event
                        on(this.element, 'click', this.__internal.clickHandler);
                        return this.delay(wait);
                    }
                    return this;
                },
                /*
                 * {Function} callback function to be invoked before dismissing the notification message.
                 * Remarks: A return value === 'false' will cancel the dismissal
                 *
                 */
                ondismiss: function () { },
                /*
                 * {Function} callback function to be invoked when the message is dismissed.
                 *
                 */
                callback: callback,
                /*
                 * Dismisses the notification message
                 * @param {Boolean} clicked A flag indicating if the dismissal was caused by a click.
                 *
                 */
                dismiss: function (clicked) {
                    if (this.__internal.pushed) {
                        clearTimers(this);
                        if (!(typeof this.ondismiss === 'function' && this.ondismiss.call(this) === false)) {
                            //detach click event
                            off(this.element, 'click', this.__internal.clickHandler);
                            // ensure element exists
                            if (typeof this.element !== 'undefined' && this.element.parentNode === element) {
                                //transition end or fallback
                                this.__internal.transitionTimeout = setTimeout(this.__internal.transitionEndHandler, transition.supported ? 1000 : 100);
                                removeClass(this.element, classes.visible);

                                // custom callback on dismiss
                                if (typeof this.callback === 'function') {
                                    this.callback.call(this, clicked);
                                }
                            }
                            popInstance(this);
                        }
                    }
                    return this;
                },
                /*
                 * Delays the notification message dismissal
                 * @param {Number} wait The time (in seconds) to wait before the message is dismissed, a value of 0 means keep open till clicked.
                 *
                 */
                delay: function (wait) {
                    clearTimers(this);
                    this.__internal.delay = typeof wait !== 'undefined' && !isNaN(+wait) ? +wait : notifier.__internal.delay;
                    if (this.__internal.delay > 0) {
                        var  self = this;
                        this.__internal.timer = setTimeout(function () { self.dismiss(); }, this.__internal.delay * 1000);
                    }
                    return this;
                },
                /*
                 * Sets the notification message contents
                 * @param {string or DOMElement} content The notification message content
                 *
                 */
                setContent: function (content) {
                    if (typeof content === 'string') {
                        clearContents(this.element);
                        this.element.innerHTML = content;
                    } else if (content instanceof window.HTMLElement && this.element.firstChild !== content) {
                        clearContents(this.element);
                        this.element.appendChild(content);
                    }
                    if(this.__internal.closeButton){
                        var close = document.createElement('span');
                        addClass(close, classes.close);
                        close.setAttribute('data-close', true);
                        this.element.appendChild(close);
                    }
                    return this;
                },
                /*
                 * Dismisses all open notifications except this.
                 *
                 */
                dismissOthers: function () {
                    notifier.dismissAll(this);
                    return this;
                }
            });
        }

        //notifier api
        return {
            /**
             * Gets or Sets notifier settings.
             *
             * @param {string} key The setting name
             * @param {Variant} value The setting value.
             *
             * @return {Object}	if the called as a setter, return the notifier instance.
             */
            setting: function (key, value) {
                //ensure init
                initialize(this);

                if (typeof value === 'undefined') {
                    //get
                    return this.__internal[key];
                } else {
                    //set
                    switch (key) {
                    case 'position':
                        this.__internal.position = value;
                        updatePosition(this);
                        break;
                    case 'delay':
                        this.__internal.delay = value;
                        break;
                    }
                }
                return this;
            },
            /**
             * [Alias] Sets dialog settings/options
             */
            set:function(key,value){
                this.setting(key,value);
                return this;
            },
            /**
             * [Alias] Gets dialog settings/options
             */
            get:function(key){
                return this.setting(key);
            },
            /**
             * Creates a new notification message
             *
             * @param {string} type The type of notification message (simply a CSS class name 'ajs-{type}' to be added).
             * @param {Function} callback  A callback function to be invoked when the message is dismissed.
             *
             * @return {undefined}
             */
            create: function (type, callback) {
                //ensure notifier init
                initialize(this);
                //create new notification message
                var div = document.createElement('div');
                div.className = classes.message + ((typeof type === 'string' && type !== '') ? ' ajs-' + type : '');
                return create(div, callback);
            },
            /**
             * Dismisses all open notifications.
             *
             * @param {Object} excpet [optional] The notification object to exclude from dismissal.
             *
             */
            dismissAll: function (except) {
                var clone = openInstances.slice(0);
                for (var x = 0; x < clone.length; x += 1) {
                    var  instance = clone[x];
                    if (except === undefined || except !== instance) {
                        instance.dismiss();
                    }
                }
            }
        };
    })();

    /**
     * Alertify public API
     * This contains everything that is exposed through the alertify object.
     *
     * @return {Object}
     */
    function Alertify() {

        // holds a references of created dialogs
        var dialogs = {};

        /**
         * Extends a given prototype by merging properties from base into sub.
         *
         * @sub {Object} sub The prototype being overwritten.
         * @base {Object} base The prototype being written.
         *
         * @return {Object} The extended prototype.
         */
        function extend(sub, base) {
            // copy dialog pototype over definition.
            for (var prop in base) {
                if (base.hasOwnProperty(prop)) {
                    sub[prop] = base[prop];
                }
            }
            return sub;
        }


        /**
        * Helper: returns a dialog instance from saved dialogs.
        * and initializes the dialog if its not already initialized.
        *
        * @name {String} name The dialog name.
        *
        * @return {Object} The dialog instance.
        */
        function get_dialog(name) {
            var dialog = dialogs[name].dialog;
            //initialize the dialog if its not already initialized.
            if (dialog && typeof dialog.__init === 'function') {
                dialog.__init(dialog);
            }
            return dialog;
        }

        /**
         * Helper:  registers a new dialog definition.
         *
         * @name {String} name The dialog name.
         * @Factory {Function} Factory a function resposible for creating dialog prototype.
         * @transient {Boolean} transient True to create a new dialog instance each time the dialog is invoked, false otherwise.
         * @base {String} base the name of another dialog to inherit from.
         *
         * @return {Object} The dialog definition.
         */
        function register(name, Factory, transient, base) {
            var definition = {
                dialog: null,
                factory: Factory
            };

            //if this is based on an existing dialog, create a new definition
            //by applying the new protoype over the existing one.
            if (base !== undefined) {
                definition.factory = function () {
                    return extend(new dialogs[base].factory(), new Factory());
                };
            }

            if (!transient) {
                //create a new definition based on dialog
                definition.dialog = extend(new definition.factory(), dialog);
            }
            return dialogs[name] = definition;
        }

        return {
            /**
             * Alertify defaults
             * 
             * @type {Object}
             */
            defaults: defaults,
            /**
             * Dialogs factory 
             *
             * @param {string}      Dialog name.
             * @param {Function}    A Dialog factory function.
             * @param {Boolean}     Indicates whether to create a singleton or transient dialog.
             * @param {String}      The name of the base type to inherit from.
             */
            dialog: function (name, Factory, transient, base) {

                // get request, create a new instance and return it.
                if (typeof Factory !== 'function') {
                    return get_dialog(name);
                }

                if (this.hasOwnProperty(name)) {
                    throw new Error('alertify.dialog: name already exists');
                }

                // register the dialog
                var definition = register(name, Factory, transient, base);

                if (transient) {

                    // make it public
                    this[name] = function () {
                        //if passed with no params, consider it a get request
                        if (arguments.length === 0) {
                            return definition.dialog;
                        } else {
                            var instance = extend(new definition.factory(), dialog);
                            //ensure init
                            if (instance && typeof instance.__init === 'function') {
                                instance.__init(instance);
                            }
                            instance['main'].apply(instance, arguments);
                            return instance['show'].apply(instance);
                        }
                    };
                } else {
                    // make it public
                    this[name] = function () {
                        //ensure init
                        if (definition.dialog && typeof definition.dialog.__init === 'function') {
                            definition.dialog.__init(definition.dialog);
                        }
                        //if passed with no params, consider it a get request
                        if (arguments.length === 0) {
                            return definition.dialog;
                        } else {
                            var dialog = definition.dialog;
                            dialog['main'].apply(definition.dialog, arguments);
                            return dialog['show'].apply(definition.dialog);
                        }
                    };
                }
            },
            /**
             * Close all open dialogs.
             *
             * @param {Object} excpet [optional] The dialog object to exclude from closing.
             *
             * @return {undefined}
             */
            closeAll: function (except) {
                var clone = openDialogs.slice(0);
                for (var x = 0; x < clone.length; x += 1) {
                    var instance = clone[x];
                    if (except === undefined || except !== instance) {
                        instance.close();
                    }
                }
            },
            /**
             * Gets or Sets dialog settings/options. if the dialog is transient, this call does nothing.
             *
             * @param {string} name The dialog name.
             * @param {String|Object} key A string specifying a propery name or a collection of key/value pairs.
             * @param {Variant} value Optional, the value associated with the key (in case it was a string).
             *
             * @return {undefined}
             */
            setting: function (name, key, value) {

                if (name === 'notifier') {
                    return notifier.setting(key, value);
                }

                var dialog = get_dialog(name);
                if (dialog) {
                    return dialog.setting(key, value);
                }
            },
            /**
             * [Alias] Sets dialog settings/options 
             */
            set: function(name,key,value){
                return this.setting(name, key,value);
            },
            /**
             * [Alias] Gets dialog settings/options 
             */
            get: function(name, key){
                return this.setting(name, key);
            },
            /**
             * Creates a new notification message.
             * If a type is passed, a class name "ajs-{type}" will be added.
             * This allows for custom look and feel for various types of notifications.
             *
             * @param  {String | DOMElement}    [message=undefined]		Message text
             * @param  {String}                 [type='']				Type of log message
             * @param  {String}                 [wait='']				Time (in seconds) to wait before auto-close
             * @param  {Function}               [callback=undefined]	A callback function to be invoked when the log is closed.
             *
             * @return {Object} Notification object.
             */
            notify: function (message, type, wait, callback) {
                return notifier.create(type, callback).push(message, wait);
            },
            /**
             * Creates a new notification message.
             *
             * @param  {String}		[message=undefined]		Message text
             * @param  {String}     [wait='']				Time (in seconds) to wait before auto-close
             * @param  {Function}	[callback=undefined]	A callback function to be invoked when the log is closed.
             *
             * @return {Object} Notification object.
             */
            message: function (message, wait, callback) {
                return notifier.create(null, callback).push(message, wait);
            },
            /**
             * Creates a new notification message of type 'success'.
             *
             * @param  {String}		[message=undefined]		Message text
             * @param  {String}     [wait='']				Time (in seconds) to wait before auto-close
             * @param  {Function}	[callback=undefined]	A callback function to be invoked when the log is closed.
             *
             * @return {Object} Notification object.
             */
            success: function (message, wait, callback) {
                return notifier.create('success', callback).push(message, wait);
            },
            /**
             * Creates a new notification message of type 'error'.
             *
             * @param  {String}		[message=undefined]		Message text
             * @param  {String}     [wait='']				Time (in seconds) to wait before auto-close
             * @param  {Function}	[callback=undefined]	A callback function to be invoked when the log is closed.
             *
             * @return {Object} Notification object.
             */
            error: function (message, wait, callback) {
                return notifier.create('error', callback).push(message, wait);
            },
            /**
             * Creates a new notification message of type 'warning'.
             *
             * @param  {String}		[message=undefined]		Message text
             * @param  {String}     [wait='']				Time (in seconds) to wait before auto-close
             * @param  {Function}	[callback=undefined]	A callback function to be invoked when the log is closed.
             *
             * @return {Object} Notification object.
             */
            warning: function (message, wait, callback) {
                return notifier.create('warning', callback).push(message, wait);
            },
            /**
             * Dismisses all open notifications
             *
             * @return {undefined}
             */
            dismissAll: function () {
                notifier.dismissAll();
            }
        };
    }
    var alertify = new Alertify();

    /**
    * Alert dialog definition
    *
    * invoked by:
    *	alertify.alert(message);
    *	alertify.alert(title, message);
    *	alertify.alert(message, onok);
    *	alertify.alert(title, message, onok);
     */
    alertify.dialog('alert', function () {
        return {
            main: function (_title, _message, _onok) {
                var title, message, onok;
                switch (arguments.length) {
                case 1:
                    message = _title;
                    break;
                case 2:
                    if (typeof _message === 'function') {
                        message = _title;
                        onok = _message;
                    } else {
                        title = _title;
                        message = _message;
                    }
                    break;
                case 3:
                    title = _title;
                    message = _message;
                    onok = _onok;
                    break;
                }
                this.set('title', title);
                this.set('message', message);
                this.set('onok', onok);
                return this;
            },
            setup: function () {
                return {
                    buttons: [
                        {
                            text: alertify.defaults.glossary.ok,
                            key: keys.ESC,
                            invokeOnClose: true,
                            className: alertify.defaults.theme.ok,
                        }
                    ],
                    focus: {
                        element: 0,
                        select: false
                    },
                    options: {
                        maximizable: false,
                        resizable: false
                    }
                };
            },
            build: function () {
                // nothing
            },
            prepare: function () {
                //nothing
            },
            setMessage: function (message) {
                this.setContent(message);
            },
            settings: {
                message: undefined,
                onok: undefined,
                label: undefined,
            },
            settingUpdated: function (key, oldValue, newValue) {
                switch (key) {
                case 'message':
                    this.setMessage(newValue);
                    break;
                case 'label':
                    if (this.__internal.buttons[0].element) {
                        this.__internal.buttons[0].element.innerHTML = newValue;
                    }
                    break;
                }
            },
            callback: function (closeEvent) {
                if (typeof this.get('onok') === 'function') {
                    var returnValue = this.get('onok').call(this, closeEvent);
                    if (typeof returnValue !== 'undefined') {
                        closeEvent.cancel = !returnValue;
                    }
                }
            }
        };
    });
    /**
     * Confirm dialog object
     *
     *	alertify.confirm(message);
     *	alertify.confirm(message, onok);
     *	alertify.confirm(message, onok, oncancel);
     *	alertify.confirm(title, message, onok, oncancel);
     */
    alertify.dialog('confirm', function () {

        var autoConfirm = {
            timer: null,
            index: null,
            text: null,
            duration: null,
            task: function (event, self) {
                if (self.isOpen()) {
                    self.__internal.buttons[autoConfirm.index].element.innerHTML = autoConfirm.text + ' (&#8207;' + autoConfirm.duration + '&#8207;) ';
                    autoConfirm.duration -= 1;
                    if (autoConfirm.duration === -1) {
                        clearAutoConfirm(self);
                        var button = self.__internal.buttons[autoConfirm.index];
                        var closeEvent = createCloseEvent(autoConfirm.index, button);

                        if (typeof self.callback === 'function') {
                            self.callback.apply(self, [closeEvent]);
                        }
                        //close the dialog.
                        if (closeEvent.close !== false) {
                            self.close();
                        }
                    }
                } else {
                    clearAutoConfirm(self);
                }
            }
        };

        function clearAutoConfirm(self) {
            if (autoConfirm.timer !== null) {
                clearInterval(autoConfirm.timer);
                autoConfirm.timer = null;
                self.__internal.buttons[autoConfirm.index].element.innerHTML = autoConfirm.text;
            }
        }

        function startAutoConfirm(self, index, duration) {
            clearAutoConfirm(self);
            autoConfirm.duration = duration;
            autoConfirm.index = index;
            autoConfirm.text = self.__internal.buttons[index].element.innerHTML;
            autoConfirm.timer = setInterval(delegate(self, autoConfirm.task), 1000);
            autoConfirm.task(null, self);
        }


        return {
            main: function (_title, _message, _onok, _oncancel) {
                var title, message, onok, oncancel;
                switch (arguments.length) {
                case 1:
                    message = _title;
                    break;
                case 2:
                    message = _title;
                    onok = _message;
                    break;
                case 3:
                    message = _title;
                    onok = _message;
                    oncancel = _onok;
                    break;
                case 4:
                    title = _title;
                    message = _message;
                    onok = _onok;
                    oncancel = _oncancel;
                    break;
                }
                this.set('title', title);
                this.set('message', message);
                this.set('onok', onok);
                this.set('oncancel', oncancel);
                return this;
            },
            setup: function () {
                return {
                    buttons: [
                        {
                            text: alertify.defaults.glossary.ok,
                            key: keys.ENTER,
                            className: alertify.defaults.theme.ok,
                        },
                        {
                            text: alertify.defaults.glossary.cancel,
                            key: keys.ESC,
                            invokeOnClose: true,
                            className: alertify.defaults.theme.cancel,
                        }
                    ],
                    focus: {
                        element: 0,
                        select: false
                    },
                    options: {
                        maximizable: false,
                        resizable: false
                    }
                };
            },
            build: function () {
                //nothing
            },
            prepare: function () {
                //nothing
            },
            setMessage: function (message) {
                this.setContent(message);
            },
            settings: {
                message: null,
                labels: null,
                onok: null,
                oncancel: null,
                defaultFocus: null,
                reverseButtons: null,
            },
            settingUpdated: function (key, oldValue, newValue) {
                switch (key) {
                case 'message':
                    this.setMessage(newValue);
                    break;
                case 'labels':
                    if ('ok' in newValue && this.__internal.buttons[0].element) {
                        this.__internal.buttons[0].text = newValue.ok;
                        this.__internal.buttons[0].element.innerHTML = newValue.ok;
                    }
                    if ('cancel' in newValue && this.__internal.buttons[1].element) {
                        this.__internal.buttons[1].text = newValue.cancel;
                        this.__internal.buttons[1].element.innerHTML = newValue.cancel;
                    }
                    break;
                case 'reverseButtons':
                    if (newValue === true) {
                        this.elements.buttons.primary.appendChild(this.__internal.buttons[0].element);
                    } else {
                        this.elements.buttons.primary.appendChild(this.__internal.buttons[1].element);
                    }
                    break;
                case 'defaultFocus':
                    this.__internal.focus.element = newValue === 'ok' ? 0 : 1;
                    break;
                }
            },
            callback: function (closeEvent) {
                clearAutoConfirm(this);
                var returnValue;
                switch (closeEvent.index) {
                case 0:
                    if (typeof this.get('onok') === 'function') {
                        returnValue = this.get('onok').call(this, closeEvent);
                        if (typeof returnValue !== 'undefined') {
                            closeEvent.cancel = !returnValue;
                        }
                    }
                    break;
                case 1:
                    if (typeof this.get('oncancel') === 'function') {
                        returnValue = this.get('oncancel').call(this, closeEvent);
                        if (typeof returnValue !== 'undefined') {
                            closeEvent.cancel = !returnValue;
                        }
                    }
                    break;
                }
            },
            autoOk: function (duration) {
                startAutoConfirm(this, 0, duration);
                return this;
            },
            autoCancel: function (duration) {
                startAutoConfirm(this, 1, duration);
                return this;
            }
        };
    });
    /**
     * Prompt dialog object
     *
     * invoked by:
     *	alertify.prompt(message);
     *	alertify.prompt(message, value);
     *	alertify.prompt(message, value, onok);
     *	alertify.prompt(message, value, onok, oncancel);
     *	alertify.prompt(title, message, value, onok, oncancel);
     */
    alertify.dialog('prompt', function () {
        var input = document.createElement('INPUT');
        var p = document.createElement('P');
        return {
            main: function (_title, _message, _value, _onok, _oncancel) {
                var title, message, value, onok, oncancel;
                switch (arguments.length) {
                case 1:
                    message = _title;
                    break;
                case 2:
                    message = _title;
                    value = _message;
                    break;
                case 3:
                    message = _title;
                    value = _message;
                    onok = _value;
                    break;
                case 4:
                    message = _title;
                    value = _message;
                    onok = _value;
                    oncancel = _onok;
                    break;
                case 5:
                    title = _title;
                    message = _message;
                    value = _value;
                    onok = _onok;
                    oncancel = _oncancel;
                    break;
                }
                this.set('title', title);
                this.set('message', message);
                this.set('value', value);
                this.set('onok', onok);
                this.set('oncancel', oncancel);
                return this;
            },
            setup: function () {
                return {
                    buttons: [
                        {
                            text: alertify.defaults.glossary.ok,
                            key: keys.ENTER,
                            className: alertify.defaults.theme.ok,
                        },
                        {
                            text: alertify.defaults.glossary.cancel,
                            key: keys.ESC,
                            invokeOnClose: true,
                            className: alertify.defaults.theme.cancel,
                        }
                    ],
                    focus: {
                        element: input,
                        select: true
                    },
                    options: {
                        maximizable: false,
                        resizable: false
                    }
                };
            },
            build: function () {
                input.className = alertify.defaults.theme.input;
                input.setAttribute('type', 'text');
                input.value = this.get('value');
                this.elements.content.appendChild(p);
                this.elements.content.appendChild(input);
            },
            prepare: function () {
                //nothing
            },
            setMessage: function (message) {
                if (typeof message === 'string') {
                    clearContents(p);
                    p.innerHTML = message;
                } else if (message instanceof window.HTMLElement && p.firstChild !== message) {
                    clearContents(p);
                    p.appendChild(message);
                }
            },
            settings: {
                message: undefined,
                labels: undefined,
                onok: undefined,
                oncancel: undefined,
                value: '',
                type:'text',
                reverseButtons: undefined,
            },
            settingUpdated: function (key, oldValue, newValue) {
                switch (key) {
                case 'message':
                    this.setMessage(newValue);
                    break;
                case 'value':
                    input.value = newValue;
                    break;
                case 'type':
                    switch (newValue) {
                    case 'text':
                    case 'color':
                    case 'date':
                    case 'datetime-local':
                    case 'email':
                    case 'month':
                    case 'number':
                    case 'password':
                    case 'search':
                    case 'tel':
                    case 'time':
                    case 'week':
                        input.type = newValue;
                        break;
                    default:
                        input.type = 'text';
                        break;
                    }
                    break;
                case 'labels':
                    if (newValue.ok && this.__internal.buttons[0].element) {
                        this.__internal.buttons[0].element.innerHTML = newValue.ok;
                    }
                    if (newValue.cancel && this.__internal.buttons[1].element) {
                        this.__internal.buttons[1].element.innerHTML = newValue.cancel;
                    }
                    break;
                case 'reverseButtons':
                    if (newValue === true) {
                        this.elements.buttons.primary.appendChild(this.__internal.buttons[0].element);
                    } else {
                        this.elements.buttons.primary.appendChild(this.__internal.buttons[1].element);
                    }
                    break;
                }
            },
            callback: function (closeEvent) {
                var returnValue;
                switch (closeEvent.index) {
                case 0:
                    this.settings.value = input.value;
                    if (typeof this.get('onok') === 'function') {
                        returnValue = this.get('onok').call(this, closeEvent, this.settings.value);
                        if (typeof returnValue !== 'undefined') {
                            closeEvent.cancel = !returnValue;
                        }
                    }
                    break;
                case 1:
                    if (typeof this.get('oncancel') === 'function') {
                        returnValue = this.get('oncancel').call(this, closeEvent);
                        if (typeof returnValue !== 'undefined') {
                            closeEvent.cancel = !returnValue;
                        }
                    }
                    if(!closeEvent.cancel){
                        input.value = this.settings.value;
                    }
                    break;
                }
            }
        };
    });

    // CommonJS
    if ( typeof module === 'object' && typeof module.exports === 'object' ) {
        module.exports = alertify;
    // AMD
    } else if ( typeof define === 'function' && define.amd) {
        define( [], function () {
            return alertify;
        } );
    // window
    } else if ( !window.alertify ) {
        window.alertify = alertify;
    }

} ( typeof window !== 'undefined' ? window : this ) );