(function($){

	/*
	* debouncedresize: special jQuery event that happens once after a window resize
	*
	* latest version and complete README available on Github:
	* https://github.com/louisremi/jquery-smartresize/blob/master/jquery.debouncedresize.js
	*
	* Copyright 2011 @louis_remi
	* Licensed under the MIT license.
	*/
	var $event = $.event, $special, resizeTimeout;

	$special = $event.special.debouncedresize = {
		setup: function() {
			$( this ).on( "resize", $special.handler );
		},
		teardown: function() {
			$( this ).off( "resize", $special.handler );
		},
		handler: function( event, execAsap ) {
			// Save the context
			var context = this,
				args = arguments,
				dispatch = function() {
					// set correct event type
					event.type = "debouncedresize";
					$event.dispatch.apply( context, args );
				};

			if ( resizeTimeout ) {
				clearTimeout( resizeTimeout );
			}

			execAsap ?
				dispatch() :
				resizeTimeout = setTimeout( dispatch, $special.threshold );
		},
		threshold: 250
	};

	// ======================= imagesLoaded Plugin ===============================
	// https://github.com/desandro/imagesloaded

	// $('#my-container').imagesLoaded(myFunction)
	// execute a callback when all images have loaded.
	// needed because .load() doesn't work on cached images

	// callback function gets image collection as argument
	//  this is the container

	// original: MIT license. Paul Irish. 2010.
	// contributors: Oren Solomianik, David DeSandro, Yiannis Chatzikonstantinou

	// blank image data-uri bypasses webkit log warning (thx doug jones)
	var BLANK = 'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw==';

	$.fn.imagesLoaded = function( callback ) {
		var $this = this,
			deferred = $.isFunction($.Deferred) ? $.Deferred() : 0,
			hasNotify = $.isFunction(deferred.notify),
			$images = $this.find('img').add( $this.filter('img') ),
			loaded = [],
			proper = [],
			broken = [];

		// Register deferred callbacks
		if ($.isPlainObject(callback)) {
			$.each(callback, function (key, value) {
				if (key === 'callback') {
					callback = value;
				} else if (deferred) {
					deferred[key](value);
				}
			});
		}

		function doneLoading() {
			var $proper = $(proper),
				$broken = $(broken);

			if ( deferred ) {
				if ( broken.length ) {
					deferred.reject( $images, $proper, $broken );
				} else {
					deferred.resolve( $images );
				}
			}

			if ( $.isFunction( callback ) ) {
				callback.call( $this, $images, $proper, $broken );
			}
		}

		function imgLoaded( img, isBroken ) {
			// don't proceed if BLANK image, or image is already loaded
			if ( img.src === BLANK || $.inArray( img, loaded ) !== -1 ) {
				return;
			}

			// store element in loaded images array
			loaded.push( img );

			// keep track of broken and properly loaded images
			if ( isBroken ) {
				broken.push( img );
			} else {
				proper.push( img );
			}

			// cache image and its state for future calls
			$.data( img, 'imagesLoaded', { isBroken: isBroken, src: img.src } );

			// trigger deferred progress method if present
			if ( hasNotify ) {
				deferred.notifyWith( $(img), [ isBroken, $images, $(proper), $(broken) ] );
			}

			// call doneLoading and clean listeners if all images are loaded
			if ( $images.length === loaded.length ){
				setTimeout( doneLoading );
				$images.unbind( '.imagesLoaded' );
			}
		}

		// if no images, trigger immediately
		if ( !$images.length ) {
			doneLoading();
		} else {
			$images.bind( 'load.imagesLoaded error.imagesLoaded', function( event ){
				// trigger imgLoaded
				imgLoaded( event.target, event.type === 'error' );
			}).each( function( i, el ) {
				var src = el.src;

				// find out if this image has been already checked for status
				// if it was, and src has not changed, call imgLoaded on it
				var cached = $.data( el, 'imagesLoaded' );
				if ( cached && cached.src === src ) {
					imgLoaded( el, cached.isBroken );
					return;
				}

				// if complete is true and browser supports natural sizes, try
				// to check for image status manually
				if ( el.complete && el.naturalWidth !== undefined ) {
					imgLoaded( el, el.naturalWidth === 0 || el.naturalHeight === 0 );
					return;
				}

				// cached images don't fire load sometimes, so we reset src, but only when
				// dealing with IE, or image is complete (loaded) and failed manual check
				// webkit hack from http://groups.google.com/group/$-dev/browse_thread/thread/eee6ab7b2da50e1f
				if ( el.readyState || el.complete ) {
					el.src = BLANK;
					el.src = src;
				}
			});
		}

		return deferred ? deferred.promise( $this ) : $this;
	};

	window.Grid = (function() {

		// list of items
		var $grid = $( '#og-grid' ),
			// the items
			$items = $grid.children( 'li' ),
			// current expanded item's index
			current = -1,
			// position (top) of the expanded item
			// used to know if the preview will expand in a different row
			previewPos = -1,
			// extra amount of pixels to scroll the window
			scrollExtra = 0,
			// extra margin when expanded (between preview overlay and the next items)
			marginExpanded = 10,
			$window = $( window ), winsize,
			$body = $( 'html, body' ),
			// transitionend events
			transEndEventNames = {
				'WebkitTransition' : 'webkitTransitionEnd',
				'MozTransition' : 'transitionend',
				'OTransition' : 'oTransitionEnd',
				'msTransition' : 'MSTransitionEnd',
				'transition' : 'transitionend'
			},
			transEndEventName = transEndEventNames[ Modernizr.prefixed( 'transition' ) ],
			// support for csstransitions
			support = Modernizr.csstransitions,
			// default settings
			settings = {
				minHeight : 500,
				speed : 350,
				easing : 'ease'
			};

		function init( config ) {
			
			// the settings..
			settings = $.extend( true, {}, settings, config );

			// preload all images
			$grid.imagesLoaded( function() {

				// save item´s size and offset
				saveItemInfo( true );
				// get window´s size
				getWinSize();
				// initialize some events
				initEvents();

			} );

		}

		// add more items to the grid.
		// the new items need to appended to the grid.
		// after that call Grid.addItems(theItems);
		function addItems( $newitems ) {

			$items = $items.add( $newitems );

			$newitems.each( function() {
				var $item = $( this );
				$item.data( {
					offsetTop : $item.offset().top,
					height : $item.height()
				} );
			} );

			initItemsEvents( $newitems );

		}

		// saves the item´s offset top and height (if saveheight is true)
		function saveItemInfo( saveheight ) {
			$items.each( function() {
				var $item = $( this );
				$item.data( 'offsetTop', $item.offset().top );
				if( saveheight ) {
					$item.data( 'height', $item.height() );
				}
			} );
		}

		function initEvents() {
			
			// when clicking an item, show the preview with the item´s info and large image.
			// close the item if already expanded.
			// also close if clicking on the item´s cross
			initItemsEvents( $items );
			
			// on window resize get the window´s size again
			// reset some values..
			$window.on( 'debouncedresize', function() {
				
				scrollExtra = 0;
				previewPos = -1;
				// save item´s offset
				saveItemInfo();
				getWinSize();
				var preview = $.data( this, 'preview' );
				if( typeof preview != 'undefined' ) {
					hidePreview();
				}

			} );

		}

		function initItemsEvents( $items ) {
			$items.on( 'click', 'span.og-close', 'a.og-close', function() {
				hidePreview();
				return false;
			} ).children( 'a' ).on( 'click', function(e) {

				var $item = $( this ).parent();
				// check if item already opened
				current === $item.index() ? hidePreview() : showPreview( $item );
				return false;

			} );
		}

		function getWinSize() {
			winsize = { width : $window.width(), height : $window.height() };
		}

		function showPreview( $item ) {

			var preview = $.data( this, 'preview' ),
				// item´s offset top
				position = $item.data( 'offsetTop' );

			scrollExtra = 0;

			// if a preview exists and previewPos is different (different row) from item´s top then close it
			if( typeof preview != 'undefined' ) {

				// not in the same row
				if( previewPos !== position ) {
					// if position > previewPos then we need to take te current preview´s height in consideration when scrolling the window
					if( position > previewPos ) {
						scrollExtra = preview.height;
					}
					hidePreview();
				}
				// same row
				else {
					preview.update( $item );
					return false;
				}
				
			}

			// update previewPos
			previewPos = position;
			// initialize new preview for the clicked item
			preview = $.data( this, 'preview', new Preview( $item ) );
			// expand preview overlay
			preview.open();

		}

		function hidePreview() {
			current = -1;
			var preview = $.data( this, 'preview' );
			preview.close();
			$.removeData( this, 'preview' );
		}

		// the preview obj / overlay
		function Preview( $item ) {
			this.$item = $item;
			this.expandedIdx = this.$item.index();
			this.create();
			this.update();
		}

		Preview.prototype = {

			create : function() {
				// create Preview structure:
				this.$title        = $( '<h2></h2>' );
				this.$description  = $( '<p></p>' );
				this.$online   = $( '<div class="online_demo"></div>' );
				this.$plugins      = $( '<div class="plugin_items"></div>' );
				this.$importdemo   = $( '<div class="importdemo_panel"></div>' );
				this.$details      = $( '<div class="og-details"></div>' ).append( this.$title, this.$description, this.$online, this.$plugins, this.$importdemo );
				this.$loading      = $( '<div class="og-loading"></div>' );
				this.$fullimage    = $( '<div class="og-fullimg"></div>' ).append( this.$loading );
				this.$closePreview = $( '<span class="og-close"></span>' );
				this.$previewInner = $( '<div class="og-expander-inner"></div>' ).append( this.$closePreview, this.$fullimage, this.$details );
				this.$previewEl    = $( '<div class="og-expander"></div>' ).append( this.$previewInner );
				// append preview element to the item
				this.$item.append( this.getEl() );
				// set the transitions for the preview and the item
				if( support ) {
					this.setTransition();
				}
			},
			update : function( $item ) {

				if( $item ) {
					this.$item = $item;
				}
				
				// if already expanded remove class "og-expanded" from current item and add it to new item
				if( current !== -1 ) {
					var $currentItem = $items.eq( current );
					$currentItem.removeClass( 'og-expanded' );
					this.$item.addClass( 'og-expanded' );
					// position the preview correctly
					this.positionPreview();
				}

				// update current value
				current = this.$item.index();

				// update preview´s content
				var $itemEl = this.$item.children( 'a' ),
					eldata = {
						importdemo : $itemEl.data( 'importdemo' ),
						largesrc : $itemEl.data( 'largesrc' ),
						title : $itemEl.data( 'title' ),
						description : $itemEl.data( 'description' ),
						online : $itemEl.data( 'online' ),
						plugins : $itemEl.data( 'plugins' )
					};

				this.$title.html( eldata.title );
				this.$description.html( eldata.description );
				this.$online.html( eldata.online );
				this.$plugins.html( eldata.plugins );
				this.$importdemo.html( eldata.importdemo );

				var self = this;
				
				// remove the current image in the preview
				if( typeof self.$largeImg != 'undefined' ) {
					self.$largeImg.remove();
				}

				// preload large image and add it to the preview
				// for smaller screens we don´t display the large image (the media query will hide the fullimage wrapper)
				if( self.$fullimage.is( ':visible' ) ) {
					this.$loading.show();
					$( '<img/>' ).load( function() {
						var $img = $( this );
						if( $img.attr( 'src' ) === self.$item.children('a').data( 'largesrc' ) ) {
							self.$loading.hide();
							self.$fullimage.find( 'img' ).remove();
							self.$largeImg = $img.fadeIn( 350 );
							self.$fullimage.append( self.$largeImg );
						}
					} ).attr( 'src', eldata.largesrc );	
				}

			},
			open : function() {

				setTimeout( $.proxy( function() {	
					// set the height for the preview and the item
					this.setHeights();
					// scroll to position the preview in the right place
					this.positionPreview();
				}, this ), 25 );

			},
			close : function() {

				var self = this,
					onEndFn = function() {
						if( support ) {
							$( this ).off( transEndEventName );
						}
						self.$item.removeClass( 'og-expanded' );
						self.$previewEl.remove();
					};

				setTimeout( $.proxy( function() {

					if( typeof this.$largeImg !== 'undefined' ) {
						this.$largeImg.fadeOut( 'fast' );
					}
					this.$previewEl.css( 'height', 0 );
					// the current expanded item (might be different from this.$item)
					var $expandedItem = $items.eq( this.expandedIdx );
					$expandedItem.css( 'height', $expandedItem.data( 'height' ) ).on( transEndEventName, onEndFn );

					if( !support ) {
						onEndFn.call();
					}

				}, this ), 25 );
				
				return false;

			},
			calcHeight : function() {

				var heightPreview = winsize.height - this.$item.data( 'height' ) - marginExpanded,
					itemHeight = winsize.height;

				if( heightPreview < settings.minHeight ) {
					heightPreview = settings.minHeight;
					itemHeight = settings.minHeight + this.$item.data( 'height' ) + marginExpanded;
				}

				this.height = heightPreview;
				this.itemHeight = itemHeight;

			},
			setHeights : function() {

				var self = this,
					onEndFn = function() {
						if( support ) {
							self.$item.off( transEndEventName );
						}
						self.$item.addClass( 'og-expanded' );
					};

				this.calcHeight();
				this.$previewEl.css( 'height', this.height );
				this.$item.css( 'height', this.itemHeight ).on( transEndEventName, onEndFn );

				if( !support ) {
					onEndFn.call();
				}

			},
			positionPreview : function() {

				// scroll page
				// case 1 : preview height + item height fits in window´s height
				// case 2 : preview height + item height does not fit in window´s height and preview height is smaller than window´s height
				// case 3 : preview height + item height does not fit in window´s height and preview height is bigger than window´s height
				var position = this.$item.data( 'offsetTop' ),
					previewOffsetT = this.$previewEl.offset().top - scrollExtra,
					scrollVal = this.height + this.$item.data( 'height' ) + marginExpanded <= winsize.height ? position : this.height < winsize.height ? previewOffsetT - ( winsize.height - this.height ) : previewOffsetT;
				
				$body.animate( { scrollTop : scrollVal }, settings.speed );

			},
			setTransition  : function() {
				this.$previewEl.css( 'transition', 'height ' + settings.speed + 'ms ' + settings.easing );
				this.$item.css( 'transition', 'height ' + settings.speed + 'ms ' + settings.easing );
			},
			getEl : function() {
				return this.$previewEl;
			}
		}

		return { 
			init    : init,
			addItems: addItems
		};

	})();

}(jQuery))
