/*
 * @author     Andrei Eftimie
 * @email      k3liutZu@gmail.com
 * @copyright  (c) Andrei Eftimie 
 * @web        http://www.eftimie.ro
 * 
 * 
 * If you want persistance, you should use the jquery.cookie.js plugin
 * 
 * You should call this plugin on the element you have defined the lowest font-size denominator.
 * Usually the body or the html, sometimes on a #content or #wrapper.
 * 
 * You site must be built using em's, or this plugin wont work. It only changes the font-size of 1 element.
 * If the other elements are not related to that element (by using em's), no font-resize magic will happen
 * 
 * Calling
 * -------
 * $('body').textResize({
 * 		plus: 		'.increase-text-size',		//Increase text size button
 * 		minus: 		'.decrease-text-size',		//Decrease text size button
 * 		reset: 		'.default-text-size',		//Reset text size button {optionally}
 * 		pace: 		1,							//How big the textsize jump will be (default 1px)
 * 		original:	16,							//The original value, to where .reset updates the text-size
 * 		limit:		[10,24]						//Lower and High limit values. It won't let the text go beyond these
 * });         
 * 
 */

(function($) {
    $.fn.textResize = function(options) {

        var defaults = {
            plus: '.increase-text-size',
            minus: '.decrease-text-size',
            reset: '.default-text-size',
            pace: 1,
            original: 12,
            limit: [8, 24] //lower and higher limit
        };

        var options = $.extend(defaults, options);
        return this.each(function() {

            var body = $(this);
            var plus = options.plus;
            var minus = options.minus;
            var reset = options.reset;
            var pace = options.pace;
            var textSize = 12;
            var original = options.original;
            var limit = options.limit;

            //we read the cookie
            var cookie = $.cookie('text-size');

            if (cookie == null || isNaN(cookie))
                cookie = 12;
            
            //we update the document with the cookie value (persistance)
            if (cookie) {
                update(cookie);
            }

            //Initialize the size variable
            init();

            //Apply events to the buttons
            $(plus).click(function() {
                if (textSize < limit[1]) {
                    newText = textSize + pace;
                    if (newText > limit[1]) newText = limit[1];
                    update(newText);
                }
                init();
                return false;
            });

            $(minus).click(function() {
                if (textSize > limit[0]) {
                    newText = textSize - pace;
                    if (newText < limit[0]) newText = limit[0];
                    update(newText);
                }
                init();
                return false;
            });

            $(reset).click(function() {
                update(original);
                init();
                return false;
            });

            function init() {
                //Current font-size
                textSize = body.css('font-size');
                if (textSize == undefined) textSize = '12px';
                textSize = parseInt(textSize.substring(0, textSize.length - 2));

                //Write cookie
                $.cookie('text-size', textSize);
            }

            function update(value) {
               body.css('font-size', value + 'px');
            }
        })

    };
})(jQuery);