// JavaScript Document

/*******************************
*
* lm_Images.js
* 
* Image Pre-caching and Rollover class
* Ver = 1.0
*
* Author: John Hutcheson, control.option
*
*******************************/



//Images Object Class Constructor
function LmImages() {
	//alert("lmImages created");
	if (document.images) {
		// Images Off Object Constructor
		this.imagesOff = new Object();
		
		// Images Over Object Object Constructor
		this.imagesOver = new Object();
	}
}




//Precache images - triggered by img onload eventhandler
LmImages.prototype.addImage =  function(imgId, imgWidth, imgHeight, onstate) {
 	//alert(imgId);
	if (this.imagesOff && this.imagesOver) {
		if (this.imagesOff[imgId] && this.imagesOver[imgId]) {
			//alert("already taken");
			return true;
		} else {
			//alert(document.getElementById(imgId).src);
			var srcStringOff = document.getElementById(imgId).src;
			var offindicator = (onstate == "on") ? "_on\." : "_off\.";
			var overindicator = "_on\.";
			var srcStringOver = srcStringOff.replace(offindicator, overindicator);
			this.imagesOff[imgId] = new Image(imgWidth, imgHeight);
			this.imagesOff[imgId].src = srcStringOff;
			this.imagesOver[imgId] = new Image(imgWidth, imgHeight);
			this.imagesOver[imgId].src = srcStringOver;
			
			return true;
		}
	}
	return false;
}





//Image Roll Over 
LmImages.prototype.swpImage = function(imgId, type, img2Id) {
	if (document.images) {
		if (this.imagesOff && this.imagesOver) {
			if (type == "on") {
				document.getElementById(imgId).src = this.imagesOver[imgId].src;
				if (img2Id) {
					document.getElementById(img2Id).src = this.imagesOver[img2Id].src;
				}
				return true;
			} else if (type == "off") {
				document.getElementById(imgId).src = this.imagesOff[imgId].src;
				if (img2Id) {
					document.getElementById(img2Id).src = this.imagesOff[img2Id].src;
				}
				return true;
			}
		}
	}
	return false;
}

//Create new object
//var lmImg = new LmImages();