// JavaScript Document
function showPic(whichPic) {
	if (document.getElementById) {
		var source = whichPic.getAttribute("href");
		var placeHolder = document.getElementById("imgholder");
		placeHolder.setAttribute("src",source);
		// show caption
		//showDesc('one');
	}
}

function showDesc(sChapNum) {
	if (document.getElementById) {
		var paraID = 'chap_' + sChapNum + '_desc';
		var childElements = document.getElementById("cutout").childNodes;
		for (var i = 0; i < childElements.length; i++) {
			if (childElements[i].tagName == 'P') {
				if (childElements[i].id == paraID) {
					childElements[i].style.display = "block"
				} else {
					childElements[i].style.display = "none"
				}
			}
		}
	}
}

function showThumbs(whichChap) {
	if (document.getElementById) {
		var sChapNum = whichChap.parentNode.id;
		var chapID = sChapNum + '_thumbs';
		var spanElements = document.getElementsByTagName("span");
		for (var i = 0; i < spanElements.length; i++) {
			if (spanElements[i].id == chapID) {
				spanElements[i].style.display = "block"
			} else {
				spanElements[i].style.display = "none"
			}
		}
		doSwap(whichChap, sChapNum, 'A')
	}
}

function doSwap(whichPic, sChapNum, sPicNum) {
	showPic(whichPic);
	showDesc(sChapNum);
	hiliteThumb(sChapNum,sPicNum)
}

// toggle the visibility of an element
function toggleVis(targetId){
	if (document.getElementById) {
		target = document.getElementById(targetId);
		if (target.style.display == "none") {
			target.style.display = "block";
		} else {
			target.style.display = "none";
		}

	}
}


// swap photos and collapse buttons 
function toggleVisButton(targetId,buttonId){
  if (document.getElementById)
        {
        target = document.getElementById(targetId);
        buttonName = document.getElementById(buttonId);
            if (target.style.display == "none")
                {
                target.style.display = "";
                } 
            
            else 
                {
                target.style.display = "none";
                }
                
            if (target.style.display == "none")
                {
                buttonName.src = "images/nav_close.gif";
                }
            else 
                {
                buttonName.src = "images/nav_open.gif";
                }
        }
}

// hilite selected thumbnail
function hiliteThumb(sChapNum,sPicNum) {
	if (document.getElementById) {
		var aPicNumList = new Array('A','B','C');
		var thumbID = 't_' + sChapNum + '_' + sPicNum;
		for (var i = 0; i < aPicNumList.length; i++) {
			var currThumbID = 't_' + sChapNum + '_' + aPicNumList[i];
			var target = document.getElementById(currThumbID);
			if (target != null) {
				var source = target.getAttribute("src");
				if (currThumbID == thumbID) {
					target.setAttribute("src",source.replace("1","2"));
				} else {
					target.setAttribute("src",source.replace("2","1"));
				}
			}
		}
	}
}

// swap photos and collapse buttons 
function hideVisButton(targetId,buttonId){
  if (document.getElementById) {
        target = document.getElementById(targetId);
        buttonName = document.getElementById(buttonId);
        target.style.display = "none";
        buttonName.src = "images/nav_close.gif";
   }
}