/**

 * 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($) {                                          // Compliant with jquery.noConflict()

$.fn.jCarouselLite = function(o) {

    o = $.extend({

        btnPrev: null,

        btnNext: null,

        btnGo: null,

        mouseWheel: false,

        auto: null,



        speed: 200,

        easing: null,



        vertical: true,

        circular: true,

        visible: 3,

        start: 0,

        scroll: 1,



        beforeStart: null,

        afterEnd: null

    }, o || {});



    return this.each(function() {                           // Returns the element collection. Chainable.



        var running = false, animCss=o.vertical?"top":"left", sizeCss=o.vertical?"height":"width";

        var div = $(this), ul = $("ul", div), 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 li = $("li", ul), itemLength = li.size(), curr = o.start;

        div.css("visibility", "visible");



        li.css({overflow: "hidden", float: o.vertical ? "none" : "left"});

        ul.css({margin: "0", padding: "0", position: "relative", "list-style-type": "none", "z-index": "1"});

        div.css({overflow: "hidden", position: "relative", "z-index": "2", left: "0px"});



        var liSize = o.vertical ? height(li) : width(li);   // Full li size(incl margin)-Used for animation

        var ulSize = liSize * itemLength;                   // size of full ul(total length, not just for the visible items)

        var divSize = liSize * v;                           // size of entire div(total length for just the visible items)



        li.css({width: li.width(), height: li.height()});

        ul.css(sizeCss, ulSize+"px").css(animCss, -(curr*liSize));



        div.css(sizeCss, "470px");                     // Width of the DIV. length of visible images



        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, val) {

                $(val).click(function() {

                    return go(o.circular ? o.visible+i : i);

                });

            });



        if(o.mouseWheel && div.mousewheel)

            div.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 li.slice(curr).slice(0,v);

        };



        function go(to) {

            if(!running) {



                if(o.beforeStart)

                    o.beforeStart.call(this, vis());



                if(o.circular) {            // If circular we are in first or last, then goto the other end

                    if(to<=o.start-v-1) {           // If first, then goto last

                        ul.css(animCss, -((itemLength-(v*2))*liSize)+"px");

                        // If "scroll" > 1, then the "to" might not be equal to the condition; it can be lesser depending on the number of elements.

                        curr = to==o.start-v-1 ? itemLength-(v*2)-1 : itemLength-(v*2)-o.scroll;

                    } else if(to>=itemLength-v+1) { // If last, then goto first

                        ul.css(animCss, -( (v) * liSize ) + "px" );

                        // If "scroll" > 1, then the "to" might not be equal to the condition; it can be greater depending on the number of elements.

                        curr = to==itemLength-v+1 ? v+1 : v+o.scroll;

                    } else curr = to;

                } else {                    // If non-circular and to points to first or last, we just return.

                    if(to<0 || to>itemLength-v) return;

                    else curr = to;

                }                           // If neither overrides it, the curr will still be "to" and we can proceed.



                running = true;



                ul.animate(

                    animCss == "left" ? { left: -(curr*liSize) } : { top: -(curr*liSize) } , o.speed, o.easing,

                    function() {

                        if(o.afterEnd)

                            o.afterEnd.call(this, vis());

                        running = false;

                    }

                );

                // Disable buttons when the carousel reaches the last/first, and enable when not

                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(el, prop) {

    return parseInt($.css(el[0], prop)) || 0;

};

function width(el) {

    return  el[0].offsetWidth + css(el, 'marginLeft') + css(el, 'marginRight');

};

function height(el) {

    return el[0].offsetHeight + css(el, 'marginTop') + css(el, 'marginBottom');

};



})(jQuery);
