/**
 * jQuery custom checkboxes
 * 
 * Copyright (c) 2008 Khavilo Dmitry (http://widowmaker.kiev.ua/checkbox/)
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 *
 * @version 1.3.0 Beta 1
 * @author Khavilo Dmitry
 * @mailto wm.morgun@gmail.com
**/

(function($){
    /* Little trick to remove event bubbling that causes events recursion */
    var CB = function(e)
    {
        if (!e) var e = window.event;
        e.cancelBubble = true;
        if (e.stopPropagation) e.stopPropagation();
    };
    
    $.fn.checkbox = function(options) {
        /* IE6 background flicker fix */
        try { document.execCommand('BackgroundImageCache', false, true);    } catch (e) {}
        
        /* Default settings */
        var settings = {
            cls: 'jquery-checkbox',  /* checkbox  */
            empty: 'empty.png'  /* checkbox  */
        };
        
        /* Processing settings */
        settings = $.extend(settings, options || {});
        
        /* Adds check/uncheck & disable/enable events */
        var addEvents = function(object)
        {
            var checked = object.checked;
            var disabled = object.disabled;
            var $object = $(object);
            
            if ( object.stateInterval )
                clearInterval(object.stateInterval);
            
            object.stateInterval = setInterval(
                function() 
                {
                    if ( object.disabled != disabled )
                        $object.trigger( (disabled = !!object.disabled) ? 'disable' : 'enable');
                    if ( object.checked != checked )
                        $object.trigger( (checked = !!object.checked) ? 'check' : 'uncheck');
                }, 
                10 /* in miliseconds. Low numbers this can decrease performance on slow computers, high will increase responce time */
            );
            return $object;
        };
        //try { console.log(this); } catch(e) {}
        
        /* Wrapping all passed elements */
        return this.each(function() 
        {
            var ch = this; /* Reference to DOM Element*/
            var $ch = addEvents(ch); /* Adds custom events and returns, jQuery enclosed object */
            
            /* Removing wrapper if already applied  */
            if (ch.wrapper) ch.wrapper.remove();
            
            /* Creating wrapper for checkbox and assigning "hover" event */
            ch.wrapper = $('<span class="' + settings.cls + '"><span class="mark"><img src="' + settings.empty + '" ' + (ch.title ? 'title="' + ch.title + '"' : '') + ' /></span></span>');
            ch.wrapperInner = ch.wrapper.children('span:eq(0)');
            ch.wrapper.hover(
                function(e) { ch.wrapperInner.addClass(settings.cls + '-hover');CB(e); },
                function(e) { ch.wrapperInner.removeClass(settings.cls + '-hover');CB(e); }
            );
            
            /* Wrapping checkbox */
            $ch.css({position: 'absolute', zIndex: -1, visibility: 'hidden'}).after(ch.wrapper);
            
            /* Ttying to find "our" label */
            var label = false;
            if ($ch.attr('id'))
            {
                label = $('label[for='+$ch.attr('id')+']');
                if (!label.length) label = false;
            }
            if (!label)
            {
                /* Trying to utilize "closest()" from jQuery 1.3+ */
                label = $ch.closest ? $ch.closest('label') : $ch.parents('label:eq(0)');
                if (!label.length) label = false;
            }
            /* Labe found, applying event hanlers */
            if (label)
            {
                label.hover(
                    function(e) { ch.wrapper.trigger('mouseover', [e]); },
                    function(e) { ch.wrapper.trigger('mouseout', [e]); }
                );
                label.click(function(e) { $ch.trigger('click',[e]); CB(e); return false;});
            }
            ch.wrapper.click(function(e) { $ch.trigger('click',[e]); CB(e); return false;});
            $ch.click(function(e) { CB(e); });
            $ch.bind('disable', function() { ch.wrapperInner.addClass(settings.cls+'-disabled');}).bind('enable', function() { ch.wrapperInner.removeClass(settings.cls+'-disabled');});
            $ch.bind('check', function() { ch.wrapper.addClass(settings.cls+'-checked' );}).bind('uncheck', function() { ch.wrapper.removeClass(settings.cls+'-checked' );});
            
            /* Disable image drag-n-drop for IE */
            $('img', ch.wrapper).bind('dragstart', function () {return false;}).bind('mousedown', function () {return false;});
            
            /* Firefox antiselection hack */
            if ( window.getSelection )
                ch.wrapper.css('MozUserSelect', 'none');
            
            /* Applying checkbox state */
            if ( ch.checked )
                ch.wrapper.addClass(settings.cls + '-checked');
            if ( ch.disabled )
                ch.wrapperInner.addClass(settings.cls + '-disabled');           
        });
    }
})(jQuery);