/**
 *
 * jquery.charcounter.js version 1.2
 * requires jQuery version 1.2 or higher
 * Copyright (c) 2007 Tom Deater (http://www.tomdeater.com)
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 * 
 */
 
(function($) {
    /**
     * attaches a character counter to each textarea element in the jQuery object
     * usage: $("#myTextArea").charCounter(max, settings);
     */
    
    $.fn.charCounter = function (max, settings) {
        max = max || 100;
        settings = $.extend({
            container: "<span></span>",
            classname: "charcounter",
            warn_classname: "zero",
            format: "(%1 characters remaining)",
            pulse: true,
            delay: 0
        }, settings);
        var p, timeout;
        
        function count(el, container) {
            el = $(el);
            if (el.val().length >= max) {
                el.val(el.val().substring(0, max));
                if (settings.pulse && !p) {
                    pulse(container, true);
                };
                if (settings.warn_classname) {
                    $(container).addClass(settings.warn_classname);
                };
            } else {
                $(container).removeClass(settings.warn_classname);
            };
            if (settings.delay > 0) {
                if (timeout) {
                    window.clearTimeout(timeout);
                }
                timeout = window.setTimeout(function () {
                    container.html(settings.format.replace(/%1/, (max - el.val().length)));
                }, settings.delay);
            } else {
                container.html(settings.format.replace(/%1/, (max - el.val().length)));
            }
        };
        
        function pulse(el, again) {
            if (p) {
                window.clearTimeout(p);
                p = null;
            };
            el.animate({ opacity: 0.1 }, 100, function () {
                $(this).animate({ opacity: 1.0 }, 100);
            });
            if (again) {
                p = window.setTimeout(function () { pulse(el) }, 200);
            };
        };
        
        return this.each(function () {
            var container;
            if (!settings.container.match(/^<.+>$/)) {
                // use existing element to hold counter message
                container = $(settings.container);
            } else {
                // append element to hold counter message (clean up old element first)
                $(this).next("." + settings.classname).remove();
                container = $(settings.container)
                                .insertBefore(this)
                                .addClass(settings.classname);
            }
            $(this)
                .unbind(".charCounter")
                .bind("keydown.charCounter", function () { count(this, container); })
                .bind("keypress.charCounter", function () { count(this, container); })
                .bind("keyup.charCounter", function () { count(this, container); })
                .bind("focus.charCounter", function () { count(this, container); })
                .bind("mouseover.charCounter", function () { count(this, container); })
                .bind("mouseout.charCounter", function () { count(this, container); })
                .bind("paste.charCounter", function () { 
                    var me = this;
                    setTimeout(function () { count(me, container); }, 10);
                });
            if (this.addEventListener) {
                this.addEventListener('input', function () { count(this, container); }, false);
            };
            count(this, container);
        });
    };

})(jQuery);