/*
		(c) 2007 SubscriberMail
		dependencies: none
		
		This script replaces an element, specified by id, with the image associated in the replacement_entity object
		
			format:
				object structure example in object literal form
				{
					container_element_id: 'the-id-of-the-element-to-be-replaced',
					replacement_img: 'the-file-path-of-the-image-to-be-replaced'
				}
			
			example:
				subscribermail_image_replacement.swap
				(
					{
					container_element_id: 'email-marketing-tools',
					replacement_img: '/img/email_marketing_tools.gif'
					}
				);
		
		That way we can have elements such as, <h1>Awesome SEO Keyword</h1> read for search engines yet
		still use an image in it's place if CSS and normal text don't work out for the design
		
		~Gavin Brady Lynch
	*/
	
	/*
		main object
	*/
	var subscribermail_image_replacement = {
		swap: function(replacement_entity) {
			var original_element = document.getElementById(replacement_entity.container_element_id);
			var img = document.createElement("img");
			img.src = replacement_entity.replacement_img;
                        img.alt = replacement_entity.replacement_alt;
			original_element.parentNode.appendChild(img);
			original_element.parentNode.removeChild(original_element);
		},
		createImage: function(replacement_entity) {
			var img = document.createElement('img');
			img.setAttribute('id', replacement_entity.container_element_id);
			img.setAttribute('src', replacement_entity.replacement_img);
			return img;
		}
	}