// Resize the slideshow images

addLoadListener(resizeSlideshow);


function resizeSlideshow()
{
	if(!document.getElementsByTagName) return false;
	if(document.getElementById("slideshowsummary")) {
	
	var image = document.getElementById("enlarge");

	// Work out the height of the viewport
	var viewportHeight = getViewportHeight();
	
	// work out the distance from the top of the viewport to the top of the image
	var positionEnlarge = getPosition(image);
	
	//Define the sizes of the image
	// height = viewportHeight less distance to the top of the image less distance for 'chrome' around the image
	var resizeWidth = 594;
	var resizeHeight = viewportHeight-positionEnlarge-15;

	
	
	var width = image.clientWidth;
	var height = image.clientHeight;
	var aspect = width/height;
	//alert ("Original: "+ width +" x "+ height);
	
	
	// Image is landscape	
	if (width > height) {
		
		// Check to see if it is larger than the resize dimensions
		if (width >= resizeWidth) {
			finalWidth=resizeWidth;
			finalHeight=resizeWidth/aspect;
			
			// If the height is higher than the resize height
			if (finalHeight >= resizeHeight) {
				// Resize it based on the height
				image.setAttribute("height",resizeHeight);	
				//alert ("Resized: "+ Math.round(resizeHeight*aspect) +" x "+ resizeHeight);
			} else {
				//Just resize it based on the width
				image.setAttribute("width",resizeWidth);				
				//alert ("Resized: "+ resizeWidth +" x "+ Math.round(resizeWidth/aspect));
			}
		} //else {
			// It isn't wider than the resize width so scale on the height.
			//image.setAttribute("height",resizeHeight);	
			//alert ("Resized: "+ Math.round(resizeHeight*aspect) +" x "+ resizeHeight);
		//} 
	}
	
	
	// Image is Portrait or square
	if (width <= height && height > resizeHeight) {
			// We need to check that the width isn't greater than the resize width before determining the final height
			finalWidth=resizeHeight*aspect;
			if (finalWidth > resizeWidth) {
				resizeHeight = finalHeight=resizeWidth/aspect;
			}			
			image.setAttribute("height",resizeHeight);		
	}
	
	
	// This is a little hack to fix a rendering issue in IE6 where the position of the 
	// TLF id isn't repositioned correctly after the image has been resized
	var tlf = document.getElementById("tlf");
	tlf.style.bottom = 0;
	
	
}
}



function getViewportHeight()
{
	var size = [0,0];

	if (typeof window.innerWidth != 'undefined')
	{
		size = [
			window.innerHeight
			];
	}
	else if (typeof document.documentElement != 'undefined'
	&& typeof document.documentElement.clientWidth != 'undefined' 
	&& document.documentElement.clientWidth != 0)
	{
		size = [
			document.documentElement.clientHeight
			];
	}
	else if (document.getElementsByTagName('body')[0] != null)
	{
		size = [
			document.getElementsByTagName('body')[0].clientHeight
			];
	}

	return size;
};




function getPosition(theElement)
{
    var positionY = 0;

    while (theElement != null)
    {
        positionY += theElement.offsetTop;
        theElement = theElement.offsetParent;
    }
    
    return [positionY];
};