function SwatImagePreviewDisplay(id, preview_src, preview_width, preview_height,
	show_title, preview_title)
{
	this.id             = id;
	this.opened         = false;
	this.show_title     = show_title;
	this.preview_title  = preview_title;
	this.preview_src    = preview_src;
	this.preview_width  = preview_width;
	this.preview_height = preview_height;

	// list of select elements to hide for IE6
	this.select_elements = [];

	YAHOO.util.Event.onDOMReady(this.init, this, true);
}

SwatImagePreviewDisplay.ie6 = false /*@cc_on || @_jscript_version < 5.7 @*/;
SwatImagePreviewDisplay.close_text = 'Close';

/**
 * Padding of preview image
 *
 * @var Number
 */
SwatImagePreviewDisplay.padding = 16;

SwatImagePreviewDisplay.prototype.init = function()
{
	this.drawOverlay();

	// link up the thumbnail image
	var image_wrapper = document.getElementById(this.id + '_wrapper');
	if (image_wrapper.tagName == 'A') {

		image_wrapper.href = '#view';
		YAHOO.util.Event.on(image_wrapper, 'click', function(e) {
			YAHOO.util.Event.preventDefault(e);
			this.open();
		}, this, true);

	} else {
		var image_link = document.createElement('a');

		image_link.title     = image_wrapper.title;
		image_link.className = image_wrapper.className;
		image_link.href      = '#view';

		while (image_wrapper.firstChild) {
			image_link.appendChild(image_wrapper.firstChild);
		}

		image_wrapper.parentNode.replaceChild(image_link, image_wrapper);

		if (this.show_title) {
			var span_tag = document.createElement('span');
			span_tag.className = 'swat-image-preview-title';
			span_tag.appendChild(document.createTextNode(image_wrapper.title))
			image_link.appendChild(span_tag);
		}

		YAHOO.util.Event.on(image_link, 'click', function(e) {
			YAHOO.util.Event.preventDefault(e);
			this.open();
		}, this, true);
	}
}

SwatImagePreviewDisplay.prototype.open = function()
{
	YAHOO.util.Event.on(document, 'keydown', this.handleKeyDown, this, true);

	// get approximate max height and width excluding close text
	var padding = SwatImagePreviewDisplay.padding;
	var max_width = YAHOO.util.Dom.getViewportWidth() - (padding * 2);
	var max_height = YAHOO.util.Dom.getViewportHeight() - (padding * 2);

	this.showOverlay();

	this.scaleImage(max_width, max_height);

	this.preview_container.style.visibility = 'hidden';
	this.preview_container.style.display = 'block';

	// now that is it displayed, adjust height for the close text
	var region = YAHOO.util.Dom.getRegion(this.preview_header);
	max_height -= (region.bottom - region.top);
	this.scaleImage(max_width, max_height);

	this.preview_container.style.visibility = 'visible';

	// x is relative to center of page
	var scroll_top = YAHOO.util.Dom.getDocumentScrollTop();
	var x = -Math.round((this.preview_image.width + padding) / 2);
	var y = Math.round((max_height - this.preview_image.height + padding) / 2) +
		scroll_top;

	this.preview_container.style.top = y + 'px';

	// set x
	this.preview_container.style.left = '50%';
	this.preview_container.style.marginLeft = x + 'px';

	this.opened = true;
}

SwatImagePreviewDisplay.prototype.scaleImage = function(max_width, max_height)
{
	// if preview image is larger than viewport width, scale down
	if (this.preview_image.width > max_width) {
		this.preview_image.height = (this.preview_image.height *
			(max_width / this.preview_image.width));

		this.preview_image.width = max_width;
	}

	// if preview image is larger than viewport height, scale down
	if (this.preview_image.height > max_height) {
		this.preview_image.width = (this.preview_image.width *
			(max_height / this.preview_image.height));

		this.preview_image.height = max_height;
	}

	// For IE 6 & 7
	this.preview_container.style.width = this.preview_image.width + 'px';
}

SwatImagePreviewDisplay.prototype.drawOverlay = function()
{
	this.overlay = document.createElement('div');

	this.overlay.className = 'swat-image-preview-overlay';
	this.overlay.style.display = 'none';

	SwatZIndexManager.raiseElement(this.overlay);

	this.draw();

	this.overlay.appendChild(this.preview_mask);
	this.overlay.appendChild(this.preview_container);

	var body = document.getElementsByTagName('body')[0];
	body.appendChild(this.overlay);
}

SwatImagePreviewDisplay.prototype.draw = function()
{
	// overlay mask
	this.preview_mask = document.createElement('a');
	this.preview_mask.className = 'swat-image-preview-mask';
	this.preview_mask.href = '#close';

	SwatZIndexManager.raiseElement(this.preview_mask);

	YAHOO.util.Event.on(this.preview_mask, 'click',
		this.handleClick, this, true);

	YAHOO.util.Event.on(this.preview_mask, 'mouseover', function(e) {
		YAHOO.util.Dom.addClass(this.preview_close_link,
			'swat-image-preview-close-hover');
	}, this, true);

	YAHOO.util.Event.on(this.preview_mask, 'mouseout', function(e) {
		YAHOO.util.Dom.removeClass(this.preview_close_link,
			'swat-image-preview-close-hover');
	}, this, true);

	// preview title
	this.title = document.createElement('span');
	this.title.className = 'swat-image-preview-title';
	if (this.preview_title) {
		this.title.appendChild(document.createTextNode(this.preview_title));
	} else {
		// non-breaking space to hold container open when there is no title
		this.title.appendChild(document.createTextNode(' '));
	}

	// close link
	this.preview_close_link = document.createElement('span');
	this.preview_close_link.href = '#close';
	this.preview_close_link.className = 'swat-image-preview-close';
	this.preview_close_link.appendChild(
		document.createTextNode(
			SwatImagePreviewDisplay.close_text
		)
	);

	SwatZIndexManager.raiseElement(this.preview_close_link);

	// header
	this.preview_header = document.createElement('span');
	this.preview_header.className = 'swat-image-preview-header';
	this.preview_header.appendChild(this.preview_close_link);
	this.preview_header.appendChild(this.title);

	SwatZIndexManager.raiseElement(this.preview_header);

	// image
	this.preview_image = document.createElement('img');
	this.preview_image.id = this.id + '_preview';
	this.preview_image.src = this.preview_src;
	this.preview_image.width = this.preview_width;
	this.preview_image.height = this.preview_height;

	// image container
	this.preview_container = document.createElement('a');
	this.preview_container.href = '#close';
	this.preview_container.className = 'swat-image-preview-container';
	this.preview_container.style.display = 'none';
	this.preview_container.appendChild(this.preview_header);
	this.preview_container.appendChild(this.preview_image);

	// For IE6 & 7
	this.preview_container.style.width = this.preview_width + 'px';

	SwatZIndexManager.raiseElement(this.preview_container);

	YAHOO.util.Event.on(this.preview_container, 'click',
		this.handleClick, this, true);

	YAHOO.util.Event.on(this.preview_container, 'mouseover', function(e) {
		YAHOO.util.Dom.addClass(this.preview_close_link,
			'swat-image-preview-close-hover');
	}, this, true);

	YAHOO.util.Event.on(this.preview_container, 'mouseout', function(e) {
		YAHOO.util.Dom.removeClass(this.preview_close_link,
			'swat-image-preview-close-hover');
	}, this, true);
}

SwatImagePreviewDisplay.prototype.showOverlay = function()
{
	if (SwatImagePreviewDisplay.ie6) {
		this.select_elements = document.getElementsByTagName('select');
		for (var i = 0; i < this.select_elements.length; i++) {
			this.select_elements[i].style._visibility =
				this.select_elements[i].style.visibility;

			this.select_elements[i].style.visibility = 'hidden';
		}
	}
	this.overlay.style.height = YAHOO.util.Dom.getDocumentHeight() + 'px';
	this.overlay.style.display = 'block';
}

SwatImagePreviewDisplay.prototype.hideOverlay = function()
{
	this.overlay.style.display = 'none';
	if (SwatImagePreviewDisplay.ie6) {
		for (var i = 0; i < this.select_elements.length; i++) {
			this.select_elements[i].style.visibility =
				this.select_elements[i].style._visibility;
		}
	}
}

SwatImagePreviewDisplay.prototype.close = function()
{
	YAHOO.util.Event.removeListener(document, 'keydown', this.handleKeyDown);

	this.hideOverlay();

	this.preview_container.style.display = 'none';

	this.opened = false;
}

SwatImagePreviewDisplay.prototype.handleClick = function(e)
{
	YAHOO.util.Event.preventDefault(e);
	this.close();
}

SwatImagePreviewDisplay.prototype.handleKeyDown = function(e)
{
	// close preview on backspace or escape
	if (e.keyCode == 8 || e.keyCode == 27) {
		YAHOO.util.Event.preventDefault(e);
		this.close();
	}
}