/*!
* 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 marquee
$.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 = $li.outerWidth(), endPos = width * -1, curPos = parseInt($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: 12 // the speed of the scrolling (keep number low)
, pauseSpeed: 5000 // 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);