/*
 * Lazy Load - jQuery plugin for lazy loading images
 *
 * Copyright (c) 2007-2009 Mika Tuupola
 *
 * Licensed under the MIT license:
 *   http://www.opensource.org/licenses/mit-license.php
 *
 * Project home:
 *   http://www.appelsiini.net/projects/lazyload
 *
 * Version:  1.5.0
 *
 */
(function($) {

	imageLoaderDefaultConfig = {
	    LoadingImage: '/assets/loader.gif',
	    FailImage: '/assets/loader.png'
	}

	$.fn.loadImage = function(pConfig, pCallback) {
   		if (pConfig) {
			var config = jQuery.extend(imageLoaderDefaultConfig, pConfig);
    	} else { 
			var config = imageLoaderDefaultConfig;
		}
		
    	var loader = jQuery(this);    
		console.log('testing');
    	loader.html('<img class="loader" src="' + config.LoadingImage + '"/>');
    	var img_src = loader.attr('source');
    	loader.removeAttr('src');

    	img = jQuery(new Image());
    	img.hide();

	    img.load(function(){

			if (loader.get(0).hasAttribute('onload')){
			    cb_js = loader.get(0).getAttribute('onload')
			    onload_cb = function() { eval(cb_js); }
			    loader.removeAttr('onload');
			} else {
			    onload_cb = null;
			}
			
			loader.html(this);
	
			jQuery(this).fadeIn('fast');
	
			if (onload_cb) onload_cb(jQuery(this));
	
	    })
	    
	    .attr('src', img_src)
	    .error(function(){ 
	    	jQuery(this).attr('src', config.FailImage);
	    	jQuery(this).attr('class', 'loader');
	    })
	   //.fadeIn('slow);
	}

    $.fn.lazyload = function(options) {
        var settings = {
            threshold    : 0,
            failurelimit : 0,
            event        : "scroll",
            effect       : "show",
            container    : window
        };
                
        if(options) {
            $.extend(settings, options);
        }

        /* Fire one scroll event per scroll. Not one scroll event per image. */
        var elements = this;
        if ("scroll" == settings.event) {
            $(settings.container).scroll(function(event) {
                
                var counter = 0;
                elements.each(function() {
                
                    if ($.abovethetop(this, settings) ||
                        $.leftofbegin(this, settings)) {
                            /* Nothing. */
                    } else if (!$.belowthefold(this, settings) &&
                        !$.rightoffold(this, settings)) {
                            $(this).trigger("appear");
                    } else {
                        if (counter++ > settings.failurelimit) {
                            return false;
                        }
                    }
                });
                /* Remove image from array so it is not looped next time. */
                var temp = $.grep(elements, function(element) {
                    return !element.loaded;
                });
                elements = $(temp);
            });
            
            
        }
        
        this.each(function() {
            var self = this;
            
            /* Save original only if it is not defined in HTML. */
            if (undefined != $(self).attr("source")) {
             //   $(self).addClass("loader");
            }
            
            if ("scroll" != settings.event || 
                    undefined == $(self).attr("src") || 
                    settings.placeholder == $(self).attr("src") || 
                    ($.abovethetop(self, settings) ||
                     $.leftofbegin(self, settings) || 
                     $.belowthefold(self, settings) || 
                     $.rightoffold(self, settings) )) {
                        
                if (settings.placeholder) {
                    $(self).attr("src", settings.placeholder);      
                } else {
                    $(self).removeAttr("src");
                }
                self.loaded = false;
            
            
            
            } else {
            	$(self).attr("src", settings.placeholder);
            	$("<img />")
                .bind("load", function() {
                	$(self)
                    .hide()
                    .removeClass('loader')
                    [settings.effect](0);
                    self.loaded = true;
                	$(self)
                        .hide()
                        .attr("src", $(self).attr("original"))
                        [settings.effect](0);
                    
                })
                .attr("src", $(self).attr("original"));
            }
            
            /* When appear is triggered load original image. */
            
            
            $(self).one("appear", function() {
            	$(this).loadImage();
            
                //$(self).removeClass('loader');
            });

            /* When wanted event is triggered load original image */
            /* by triggering appear.                              */
            if ("scroll" != settings.event) {
            	
                $(self).bind(settings.event, function(event) {
                    if (!self.loaded) {
                        $(self).trigger("appear");   
                    }
                });
            }
        });
        
        /* Force initial check if images should appear. */
        $(settings.container).trigger(settings.event);
        
        return this;

    };

    /* Convenience methods in jQuery namespace.           */
    /* Use as  $.belowthefold(element, {threshold : 100, container : window}) */

    $.belowthefold = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
                var fold = $(window).height() + $(window).scrollTop();
        } else {
                var fold = $(settings.container).offset().top + $(settings.container).height();
        }
        return fold <= ($(element).offset().top - $(element).height() - $(window).scrollTop()) - settings.threshold;
	};
    
    $.rightoffold = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).width() + $(window).scrollLeft();
        } else {
            var fold = $(settings.container).offset().left + $(settings.container).width();
        }
        return fold <= $(element).offset().left - settings.threshold;
    };
        
    $.abovethetop = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).scrollTop();
        } else {
            var fold = $(settings.container).offset().top;
        }
        return fold >= $(element).offset().top + settings.threshold  + $(element).height();
    };
    
    $.leftofbegin = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).scrollLeft();
        } else {
            var fold = $(settings.container).offset().left;
        }
        return fold >= $(element).offset().left + settings.threshold + $(element).width();
    };
    /* Custom selectors for your convenience.   */
    /* Use as $("img:below-the-fold").something() */

    $.extend($.expr[':'], {
        "below-the-fold" : "$.belowthefold(a, {threshold : 0, container: window})",
        "above-the-fold" : "!$.belowthefold(a, {threshold : 0, container: window})",
        "right-of-fold"  : "$.rightoffold(a, {threshold : 0, container: window})",
        "left-of-fold"   : "!$.rightoffold(a, {threshold : 0, container: window})"
    });
    
})(jQuery);