/*!

 * Marquee jQuery Plug-in

 *

 * Copyright 2009 Giva, Inc. (http://www.givainc.com/labs/) 

 * 

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 * 

 * 	http://www.apache.org/licenses/LICENSE-2.0

 * 

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 *

 * Date: 2009-05-20

 * Rev:  1.0.01

 */

;(function($){

	// set the version of the link select

	$.marquee = {version: "1.0.01"};

	

	$.fn.marquee = function(options) {

		var method = typeof arguments[0] == "string" && arguments[0];

		var args = method && Array.prototype.slice.call(arguments, 1) || arguments;

		// get a reference to the first marquee found

		var self = (this.length == 0) ? null : $.data(this[0], "marquee");

		

		// if a method is supplied, execute it for non-empty results

		if( self && method && this.length ){



			// if request a copy of the object, return it			

			if( method.toLowerCase() == "object" ) return self;

			// if method is defined, run it and return either it's results or the chain

			else if( self[method] ){

				// define a result variable to return to the jQuery chain

				var result;

				this.each(function (i){

					// apply the method to the current element

					var r = $.data(this, "marquee")[method].apply(self, args);

					// if first iteration we need to check if we're done processing or need to add it to the jquery chain

					if( i == 0 && r ){

						// if this is a jQuery item, we need to store them in a collection

						if( !!r.jquery ){

							result = $([]).add(r);

						// otherwise, just store the result and stop executing

						} else {

							result = r;

							// since we're a non-jQuery item, just cancel processing further items

							return false;

						}

					// keep adding jQuery objects to the results

					} else if( !!r && !!r.jquery ){

						result = result.add(r);

					}

				});



				// return either the results (which could be a jQuery object) or the original chain

				return result || this;

			// everything else, return the chain

			} else return this;

		// initializing request

		} else {

			// create a new marquee for each object found

			return this.each(function (){

				new $.Marquee(this, options);

			});

		};

	};



	$.Marquee = function (marquee, options){

		options = $.extend({}, $.Marquee.defaults, options);

		

		var self = this, $marquee = $(marquee), $lis = $marquee.find("> li"), current = -1, hard_paused = false, paused = false, loop_count = 0;



		// store a reference to this marquee

		$.data($marquee[0], "marquee", self);

		

		// pause the marquee

		this.pause = function (){

			// mark as hard pause (no resume on hover)

			hard_paused = true;

			// pause scrolling

			pause();

		}

		

		// resume the marquee

		this.resume = function (){

			// mark as hard pause (no resume on hover)

			hard_paused = false;

			// resume scrolling

			resume();

		}

		

		// update the marquee

		this.update = function (){

			var iCurrentCount = $lis.length;



			// update the line items

			$lis = $marquee.find("> li");

			

			// if we only have one item, show the next item by resuming playback (which will scroll to the next item)

			if( iCurrentCount <= 1 ) resume();

		}



		// code to introduce the new marquee message

		function show(i){

			// if we're already scrolling an item, stop processing

			if( $lis.filter("." + options.cssShowing).length > 0 ) return false;

			

			var $li = $lis.eq(i);

			

			// run the beforeshow callback

			if( $.isFunction(options.beforeshow) ) options.beforeshow.apply(self, [$marquee, $li]);



			var params = {

				top: (options.yScroll == "top" ? "-" : "+") + $li.outerHeight() + "px"

				, left: 0

			};

			

			$marquee.data("marquee.showing", true);

			$li.addClass(options.cssShowing);

	

			$li.css(params).animate({top: "0px"}, options.showSpeed, options.fxEasingShow, function (){ 

				// run the show callback

				if( $.isFunction(options.show) ) options.show.apply(self, [$marquee, $li]);

				$marquee.data("marquee.showing", false);

				scroll($li);

			});

		}



		// keep the message on the screen for the user to read, scrolling long messages

		function scroll($li, delay){

			// if paused, stop processing

			if( paused == true ) return false;



			// get the delay speed

			delay = delay || options.pauseSpeed;

			// if	item is wider than marquee, then scroll

			if( doScroll($li) ){

				setTimeout(function (){

					// if paused, stop processing (we need to check to see if the pause state has changed)

					if( paused == true ) return false;



					var width = $li.outerWidth(), endPos = - 60 + width * -1, curPos = parseInt($li.css("left"), 10);



					// scroll the message to the left					

					$li.animate({left: endPos + "px"}, ((width + curPos) * options.scrollSpeed), options.fxEasingScroll, function (){ finish($li); });

				}, delay);

			} else if ( $lis.length > 1 ){

				setTimeout(function (){

					// if paused, stop processing (we need to check to see if the pause state has changed)

					if( paused == true ) return false;



					// scroll the message down

					$li.animate({top: (options.yScroll == "top" ? "+" : "-") + $marquee.innerHeight() + "px"}, options.showSpeed, options.fxEasingScroll);

					// finish showing this message

					finish($li);

				}, delay);

			}

			

		}

		

		function finish($li){

			// run the aftershow callback, only after we've displayed the first option

			if( $.isFunction(options.aftershow) ) options.aftershow.apply(self, [$marquee, $li]);

			

			// mark that we're done scrolling this element

			$li.removeClass(options.cssShowing);

			

			// show the next message

			showNext();

		}



		// this function will pause the current animation

		function pause(){

			// mark the message as paused

			paused = true;

			// don't stop animation if we're just beginning to show the marquee message

			if( $marquee.data("marquee.showing") != true ){

				// we must dequeue() the animation to ensure that it does indeed stop animation

				$lis.filter("." + options.cssShowing).dequeue().stop();

			}

		}

		

		// this function will resume the previous animation

		function resume(){

			// mark the message as resumed

			paused = false;

			// don't resume animation if we haven't completed introducing the message

			if( $marquee.data("marquee.showing") != true ) scroll($lis.filter("." + options.cssShowing), 1);

		}



		// determine if we should pause on hover

		if( options.pauseOnHover ){

			$marquee.hover(

				function (){

					// if hard paused, prevent hover events

					if( hard_paused ) return false;

					// pause scrolling

					pause();

				}

				, function (){

					// if hard paused, prevent hover events

					if( hard_paused ) return false;

					// resume scrolling

					resume();

				}

			);

		}

		

		// determines if the message needs to be scrolled to read

		function doScroll($li){

			return ($li.outerWidth() > $marquee.innerWidth());

		}



		// show the next message in the queue		

		function showNext(){

			// increase the current counter (starts at -1, to indicate a new marquee beginning)

			current++;

			

			// if we only have 1 entry and it doesn't need to scroll, just cancel processing

			if( current >= $lis.length ){

				// if we've reached our loop count, cancel processing

				if( !isNaN(options.loop) && options.loop > 0 && (++loop_count >= options.loop ) ) return false;

				current = 0;

			} 

			

			// show the next message

			show(current);

		}

		

		// run the init callback

		if( $.isFunction(options.init) ) options.init.apply(self, [$marquee, options]);

		

		// show the first item

		showNext();

	};



	$.Marquee.defaults = {

		  yScroll: "top"                          // the position of the marquee initially scroll (can be either "top" or "bottom")

		, showSpeed: 850                          // the speed of to animate the initial dropdown of the messages

		, scrollSpeed: 10                         // the speed of the scrolling (keep number low)

		, pauseSpeed: 2000                        // the time to wait before showing the next message or scrolling current message

		, pauseOnHover: true                      // determine if we should pause on mouse hover

		, loop: -1                                // determine how many times to loop through the marquees (#'s < 0 = infinite)

		, fxEasingShow: "swing"                   // the animition easing to use when showing a new marquee

		, fxEasingScroll: "linear"                // the animition easing to use when showing a new marquee



		// define the class statements

		, cssShowing: "marquee-showing"



		// event handlers

		, init: null                              // callback that occurs when a marquee is initialized

		, beforeshow: null                        // callback that occurs before message starts scrolling on screen

		, show: null                              // callback that occurs when a new marquee message is displayed

		, aftershow: null                         // callback that occurs after the message has scrolled

	};



})(jQuery);