/*
    newsTicker.js v0.1a
    Last updated: 04 October 2010
    Created by: Ed Cousins (Perform Group)
*/

(function($) {
    
    $.fn.newsticker = function(options) {
        
        var config = {
            velocity: 0.05,
            type: "scroll",
            direction: "ltr"
            //debug: "true"
        };
        
    if(options) $.extend(config, options);
    
    return this.each(function(){
         
        var ticker = $(this);
        ticker.addClass('ticker');
        
        var tickerWrap = ticker.wrap("<div class='tickerWrap'></div>"); // This wrap is the mask
        var tickerWidth = 0;
        var containerWidth = tickerWrap.width();    // This sets the width of the mask
        var individualTickerWidth = 0;
		var itemWidth;
		
        // Find the li's within the ticker and work out the total width
        ticker.find("li").each(function(i){
			if(i==0){
				itemWidth = jQuery(this, i).outerWidth(true);
			}
            tickerWidth += jQuery(this, i).outerWidth(true);
		});
		
		
        ticker.width(tickerWidth);
        
        // Calculate the distance and timing for the ticker items to follow
        var totalDistance = tickerWidth + containerWidth;
        var loopTime = totalDistance/config.velocity;

		switch(config.type){
			case "fade":
				fadeTicker();
				break;
			case "scroll":
				scrollTicker();
		}

		function fadeTicker() {
			var newsInterval;
			var finalLeft = (ticker.children().size() - 1) * -itemWidth;
			var leftage = 0;
			var playing = true;
			
			function moveNext() {
				if (leftage <= finalLeft) {
					leftage = 0;
				} else {
					leftage = leftage - itemWidth
				}
				ticker.css("left", leftage);
			};
			
			function movePrevious() {
				if (leftage >= 0) {
					leftage = finalLeft;
				} else {
					leftage = leftage + itemWidth
				}
				ticker.css("left", leftage);
			};
			
			function fadeNext(){
				ticker.fadeOut(2000, function(){
					moveNext();
					ticker.fadeIn(2000);
				});
			};
			
			function startPlaying(backwards){
				newsInterval = setInterval(function(){fadeNext()}, 4000);
				playing = true;
			};
			
			function stopPlaying(){
				clearInterval(newsInterval);
				ticker.show();
				playing = false;
			};
			
			$(".rewind").bind('click', function() {
				stopPlaying();
				movePrevious();
			});
			
			$(".fastforward").bind('click', function() {
				stopPlaying();
				moveNext();
			});
			
			$(".pause").bind('click', function() {
				if(playing){
					stopPlaying();
				}else{
					startPlaying();
				}
			});
			
			startPlaying();
		}
		
		function scrollTicker() {
			// Scroll direction
			if(config.direction == "ltr") {
				ticker.css("left", containerWidth); // Set the left CSS for the UL to outside the right of the mask
				function scrollLeft(distance, velocity){
					ticker.animate({left: '-='+ distance}, velocity, "linear", function(){
						ticker.css("left", containerWidth);
						scrollLeft(totalDistance, loopTime);
					});
				}
				scrollLeft(totalDistance, loopTime);
				
				ticker.hover(function() {
					ticker.stop();
				},
				function(){
					var offset = ticker.offset();   // find current relative position of ticker
					var remainingDistance = offset.left + tickerWidth;  // work out the remaining distance to travel
					var remainingTime = remainingDistance/config.velocity; // work out the remaining time to complete the loop
					scrollLeft(remainingDistance, remainingTime);
				});
			}        
			else {
				ticker.css("left", -tickerWidth);   // Set the left CSS for the UL to outside the left of the mask
				function scrollRight(distance, velocity){
					ticker.animate({left: '+='+ distance}, velocity, "linear", function(){
						ticker.css("left", -tickerWidth);
						scrollRight(totalDistance, loopTime);
					});
				}
				scrollRight(totalDistance, loopTime);
				
				ticker.hover(function() {
					ticker.stop();
				},
				function(){
					var offset = ticker.offset();   // find current relative position of ticker
					var remainingDistance = containerWidth - offset.left; // work out the remaining distance to travel
					var remainingTime = remainingDistance/config.velocity; // work out the remaining time to complete the loop
					scrollRight(remainingDistance, remainingTime);
				});
			}
		}
    });
    };    
})(jQuery);