/**
 * jCarouselLite - jQuery plugin to navigate images/any content in a carousel style widget.
 * @requires jQuery v1.2 or above
 *
 * http://gmarwaha.com/jquery/jcarousellite/
 *
 * Copyright (c) 2007 Ganeshji Marwaha (gmarwaha.com)
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 *
 * Version: 1.0.1
 * Note: Requires jquery 1.2 or above from version 1.0.1
 */

/**
 * Creates a carousel-style navigation widget for images/any-content from a simple HTML markup.
 *
 * The HTML markup that is used to build the carousel can be as simple as...
 *
 *  <div class="carousel">
 *      <ul>
 *          <li><img src="image/1.jpg" alt="1"></li>
 *          <li><img src="image/2.jpg" alt="2"></li>
 *          <li><img src="image/3.jpg" alt="3"></li>
 *      </ul>
 *  </div>
 *
 * As you can see, this snippet is nothing but a simple div containing an unordered list of images.
 * You don't need any special "class" attribute, or a special "css" file for this plugin.
 * I am using a class attribute just for the sake of explanation here.
 *
 * To navigate the elements of the carousel, you need some kind of navigation buttons.
 * For example, you will need a "previous" button to go backward, and a "next" button to go forward.
 * This need not be part of the carousel "div" itself. It can be any element in your page.
 * Lets assume that the following elements in your document can be used as next, and prev buttons...
 *
 * <button class="prev">&lt;&lt;</button>
 * <button class="next">&gt;&gt;</button>
 *
 * Now, all you need to do is call the carousel component on the div element that represents it, and pass in the
 * navigation buttons as options.
 *
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev"
 * });
 *
 * That's it, you would have now converted your raw div, into a magnificient carousel.
 *
 * There are quite a few other options that you can use to customize it though.
 * Each will be explained with an example below.
 *
 * @param an options object - You can specify all the options shown below as an options object param.
 *
 * @option btnPrev, btnNext : string - no defaults
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev"
 * });
 * @desc Creates a basic carousel. Clicking "btnPrev" navigates backwards and "btnNext" navigates forward.
 *
 * @option btnGo - array - no defaults
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      btnGo: [".0", ".1", ".2"]
 * });
 * @desc If you don't want next and previous buttons for navigation, instead you prefer custom navigation based on
 * the item number within the carousel, you can use this option. Just supply an array of selectors for each element
 * in the carousel. The index of the array represents the index of the element. What i mean is, if the
 * first element in the array is ".0", it means that when the element represented by ".0" is clicked, the carousel
 * will slide to the first element and so on and so forth. This feature is very powerful. For example, i made a tabbed
 * interface out of it by making my navigation elements styled like tabs in css. As the carousel is capable of holding
 * any content, not just images, you can have a very simple tabbed navigation in minutes without using any other plugin.
 * The best part is that, the tab will "slide" based on the provided effect. :-)
 *
 * @option mouseWheel : boolean - default is false
 * @example
 * $(".carousel").jCarouselLite({
 *      mouseWheel: true
 * });
 * @desc The carousel can also be navigated using the mouse wheel interface of a scroll mouse instead of using buttons.
 * To get this feature working, you have to do 2 things. First, you have to include the mouse-wheel plugin from brandon.
 * Second, you will have to set the option "mouseWheel" to true. That's it, now you will be able to navigate your carousel
 * using the mouse wheel. Using buttons and mouseWheel or not mutually exclusive. You can still have buttons for navigation
 * as well. They complement each other. To use both together, just supply the options required for both as shown below.
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      mouseWheel: true
 * });
 *
 * @option auto : number - default is null, meaning autoscroll is disabled by default
 * @example
 * $(".carousel").jCarouselLite({
 *      auto: 800,
 *      speed: 500
 * });
 * @desc You can make your carousel auto-navigate itself by specfying a millisecond value in this option.
 * The value you specify is the amount of time between 2 slides. The default is null, and that disables auto scrolling.
 * Specify this value and magically your carousel will start auto scrolling.
 *
 * @option speed : number - 200 is default
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      speed: 800
 * });
 * @desc Specifying a speed will slow-down or speed-up the sliding speed of your carousel. Try it out with
 * different speeds like 800, 600, 1500 etc. Providing 0, will remove the slide effect.
 *
 * @option easing : string - no easing effects by default.
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      easing: "bounceout"
 * });
 * @desc You can specify any easing effect. Note: You need easing plugin for that. Once specified,
 * the carousel will slide based on the provided easing effect.
 *
 * @option vertical : boolean - default is false
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      vertical: true
 * });
 * @desc Determines the direction of the carousel. true, means the carousel will display vertically. The next and
 * prev buttons will slide the items vertically as well. The default is false, which means that the carousel will
 * display horizontally. The next and prev items will slide the items from left-right in this case.
 *
 * @option circular : boolean - default is true
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      circular: false
 * });
 * @desc Setting it to true enables circular navigation. This means, if you click "next" after you reach the last
 * element, you will automatically slide to the first element and vice versa. If you set circular to false, then
 * if you click on the "next" button after you reach the last element, you will stay in the last element itself
 * and similarly for "previous" button and first element.
 *
 * @option visible : number - default is 3
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      visible: 4
 * });
 * @desc This specifies the number of items visible at all times within the carousel. The default is 3.
 * You are even free to experiment with real numbers. Eg: "3.5" will have 3 items fully visible and the
 * last item half visible. This gives you the effect of showing the user that there are more images to the right.
 *
 * @option start : number - default is 0
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      start: 2
 * });
 * @desc You can specify from which item the carousel should start. Remember, the first item in the carousel
 * has a start of 0, and so on.
 *
 * @option scrool : number - default is 1
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      scroll: 2
 * });
 * @desc The number of items that should scroll/slide when you click the next/prev navigation buttons. By
 * default, only one item is scrolled, but you may set it to any number. Eg: setting it to "2" will scroll
 * 2 items when you click the next or previous buttons.
 *
 * @option beforeStart, afterEnd : function - callbacks
 * @example
 * $(".carousel").jCarouselLite({
 *      btnNext: ".next",
 *      btnPrev: ".prev",
 *      beforeStart: function(a) {
 *          alert("Before animation starts:" + a);
 *      },
 *      afterEnd: function(a) {
 *          alert("After animation ends:" + a);
 *      }
 * });
 * @desc If you wanted to do some logic in your page before the slide starts and after the slide ends, you can
 * register these 2 callbacks. The functions will be passed an argument that represents an array of elements that
 * are visible at the time of callback.
 *
 *
 * @cat Plugins/Image Gallery
 * @author Ganeshji Marwaha/ganeshread@gmail.com
 */

(function ($) {
    $.fn.jCarouselLite = function (o) {
        o = $.extend({
            btnPrev: null,
            btnNext: null,
            btnGo: null,
            mouseWheel: false,
            auto: null,
            speed: 200,
            easing: null,
            vertical: false,
            circular: true,
            visible: 3,
            start: 0,
            scroll: 1,
            beforeStart: null,
            afterEnd: null
        }, o || {});
        return this.each(function () {
            var b = false,
                animCss = o.vertical ? "top" : "left",
                sizeCss = o.vertical ? "height" : "width";
            var c = $(this),
                ul = $("ul", c),
                tLi = $("li", ul),
                tl = tLi.size(),
                v = o.visible;
            if (o.circular) {
                ul.prepend(tLi.slice(tl - v - 1 + 1).clone()).append(tLi.slice(0, v).clone());
                o.start += v
            }
            var f = $("li", ul),
                itemLength = f.size(),
                curr = o.start;
            c.css("visibility", "visible");
            f.css({
                overflow: "hidden",
                float: o.vertical ? "none" : "left"
            });
            ul.css({
                margin: "0",
                padding: "0",
                position: "relative",
                "list-style-type": "none",
                "z-index": "1"
            });
            c.css({
                overflow: "hidden",
                position: "relative",
                "z-index": "2",
                left: "0px"
            });
            var g = o.vertical ? height(f) : width(f);
            var h = g * itemLength;
            var j = g * v;
            f.css({
                width: f.width(),
                height: f.height()
            });
            ul.css(sizeCss, h + "px").css(animCss, -(curr * g));
            c.css(sizeCss, j + "px");
            
            if(itemLength < 5) {
                $(".next").css({
                    display: "none"
                });
                $(".prev").css({
                    display: "none"
                })
            }
            
            if (o.btnPrev) $(o.btnPrev).click(function () {
                return go(curr - o.scroll)
            });
            if (o.btnNext) $(o.btnNext).click(function () {
                return go(curr + o.scroll)
            });
            if (o.btnGo) $.each(o.btnGo, function (i, a) {
                $(a).click(function () {
                    return go(o.circular ? o.visible + i : i)
                })
            });
            if (o.mouseWheel && c.mousewheel) c.mousewheel(function (e, d) {
                return d > 0 ? go(curr - o.scroll) : go(curr + o.scroll)
            });
            if (o.auto) setInterval(function () {
                go(curr + o.scroll)
            }, o.auto + o.speed);

            function vis() {
                return f.slice(curr).slice(0, v)
            };

            function go(a) {
                if (!b) {
                    if (o.beforeStart) o.beforeStart.call(this, vis());
                    if (o.circular) {
                        if (a <= o.start - v - 1) {
                            ul.css(animCss, -((itemLength - (v * 2)) * g) + "px");
                            curr = a == o.start - v - 1 ? itemLength - (v * 2) - 1 : itemLength - (v * 2) - o.scroll
                        } else if (a >= itemLength - v + 1) {
                            ul.css(animCss, -((v) * g) + "px");
                            curr = a == itemLength - v + 1 ? v + 1 : v + o.scroll
                        } else curr = a
                    } else {
                        if (a < 0 || a > itemLength - v) return;
                        else curr = a
                    }
                    b = true;
                    ul.animate(animCss == "left" ? {
                        left: -(curr * g)
                    } : {
                        top: -(curr * g)
                    }, o.speed, o.easing, function () {
                        if (o.afterEnd) o.afterEnd.call(this, vis());
                        b = false
                    });
                    if (!o.circular) {
                        $(o.btnPrev + "," + o.btnNext).removeClass("disabled");
                        $((curr - o.scroll < 0 && o.btnPrev) || (curr + o.scroll > itemLength - v && o.btnNext) || []).addClass("disabled")
                    }
                }
                return false
            }
        })
    };

    function css(a, b) {
        return parseInt($.css(a[0], b)) || 0
    };

    function width(a) {
        return a[0].offsetWidth + css(a, 'marginLeft') + css(a, 'marginRight')
    };

    function height(a) {
        if ($.browser.msie)
            return a[0].offsetHeight + css(a, 'marginTop') + css(a, 'marginBottom') + 4;
        else return a[0].offsetHeight + css(a, 'marginTop') + css(a, 'marginBottom')
    }
})(jQuery);