/*
 *
 * Author: sandi.winter@gmail.com
 * http://www.alls-soft.com
 *
 */

function WImgChanger(){
	
	var imgEl;
	var imgList;
	var path;
  
	this.selectImg = selectImg;
	this.selectFirst = selectFirst;
	this.loadNext = loadNext;
	this.loadPrev = loadPrev;
	this.relPath  = relPath;
	this.selectImgByNum = selectImgByNum;
	
	function relPath(newpath){
		imgEl = document.getElementById("imgch1");
		imgList = document.getElementById("imglist");
		path=newpath;
	}
	
	function loadNext(){
		var curr = imgEl.alt;
		var lis = imgList.getElementsByTagName("a");
		for (var i=0; i<lis.length; i++) {
			if(lis[i].id==curr){
				if(i+1==lis.length){
					imgEl.src=path+lis[0].id+'_thumb.jpg';
					imgEl.alt=lis[0].id;
					break;
				}
				else{
					imgEl.src=path+lis[i+1].id+'_thumb.jpg';
					imgEl.alt=lis[i+1].id;
					break;
				}
			}
		}
	}
	
	function loadPrev(){
		var curr = imgEl.alt;
		var lis = imgList.getElementsByTagName("a");
		for (var i=0; i<lis.length; i++) {
			if(lis[i].id==curr){
				if(i==0){
					imgEl.src=path+lis[lis.length-1].id+'_thumb.jpg';
					imgEl.alt=lis[lis.length-1].id;
					break;
				}
				else{
					imgEl.src=path+lis[i-1].id+'_thumb.jpg';
					imgEl.alt=lis[i-1].id;
					break;
				}
			}
		}
	}
	
	function selectImg(imgalt){
		imgEl.src=path+imgalt+'_thumb.jpg';
		imgEl.alt=imgalt;
	}
	
	function selectImgByNum(num){
		var lis = imgList.getElementsByTagName("a");
		
		if(num<0){
			imgEl.src=path+lis[0].id+'_thumb.jpg';
			imgEl.alt=lis[0].id;
		}
		else if(num>=lis.length){
			imgEl.src=path+lis[lis.length-1].id+'_thumb.jpg';
			imgEl.alt=lis[lis.length-1].id;
		}
		else{
			imgEl.src=path+lis[num].id+'_thumb.jpg';
			imgEl.alt=lis[num].id;
		}
	}
	
	function selectFirst(){
		var lis = imgList.getElementsByTagName("a");
		imgEl.src=path+lis[0].id+'_thumb.jpg';
		imgEl.alt=lis[0].id;
	}
}