var flagNext = true;
var flagPrev = true;

function showHideElement(id,display,visibility) {		
	var idObj = document.getElementById(id);
	idObj.style.display = display;
	idObj.style.visibility = visibility;
}

function getNextPrev(flag,imageArr,jsonArr,styleId) {

	id = document.getElementById(styleId);
	/********* Get Imeage *********/
	if(flag == 0 && !flagNext) index = imageArr.length - 2;
	if(flag == 1 && !flagPrev) index = 1;
	id.style.backgroundImage = 	"url(" + imageArr[index].src + ")"; //Set Background
	changeDescription(jsonArr);
	
	if(flag == 1) {
		if(flagNext) index++;	
		if(index == imageArr.length) {
			 index = index - 1; 
			 flagNext = false;
		}
		flagPrev = true;
	} else if(flag == 0) {
		index--;
		flagNext = true;
		flagPrev = false;
	}
	 
	if(index < 0) index = 0;	
	if(index > 1)showHideElement('prev_pic','block','visible');
}

function changeDescription(jsonArr) {
	var idTitle = document.getElementById('r_box2_txt');
	idTitle.innerHTML = "<a href=\"article.php?id=" + jsonArr.imagesL[index].id + "\">" + jsonArr.imagesL[index].nameArt + "</a>";
	document['tnImg'].src = loadedImagesTn[index].src;
}