//==================================================================
// NAME:
//		bioLocate.js
// PURPOSE:
//		Javascript location functions
// HISTORY:
//		09-05-2007, Craig Helgason (craig.helgason@und.edu)
//==================================================================

//------------------------------------------------------------------
// NAME:
//		findPosX
// PURPOSE:
//		Return the current left (X) position of the object on the page
// INPUTS:
//		obj = the object to find the position of
// RETURNS:
//		The X location.
// PROCEDURE:
//		If offsetParent is supported, traverse up the object tree, incrementing
//		the left position.  Else if obj.x is supported, add it to left position
//------------------------------------------------------------------
function findPosX(obj){
	var curleft = 0;
	if (obj.offsetParent){
		while (obj.offsetParent){
			curleft += obj.offsetLeft;
			obj = obj.offsetParent;
		}
	}
	else if (obj.x)
		curleft += obj.x;
	return curleft;
}

//------------------------------------------------------------------
// NAME:
//		findPosY
// PURPOSE:
//		Return the current top (Y) position of the object on the page
// INPUTS:
//		obj = the object to find the position of
// RETURNS:
//		The Y location.
// PROCEDURE:
//		If offsetParent is supported, traverse up the object tree, incrementing
//		the top position.  Else if obj.y is supported, add it to top position
//------------------------------------------------------------------
function findPosY(obj){
	var curtop = 0;
	if (obj.offsetParent){
		while (obj.offsetParent){
			curtop += obj.offsetTop
			obj = obj.offsetParent;
		}
	}
	else if (obj.y)
		curtop += obj.y;
	return curtop;
}

//------------------------------------------------------------------
// NAME:
//		toggle
// PURPOSE:
//		Toggles the visibility of expandable blocks of content
// INPUTS:
//		id = the id of the content block to toggle
// RETURNS:
//		none
// PROCEDURE:
//		Set object variables
//			- "section" to the content block
//			- "sectionImage" to the expand/contract graphic
//			  (in our case, small plus/minus graphics used throughtout UMAC sites)
//			- "main" to the sub content block below the link/title.
//		If the block is hidden, show it
//			- set display style to "block"
//			- set image source to minus/contract graphic
//			- get the top position of the sub content block
//			- scroll the window to display the entire sub content block
//			  (this is so the block won't expand beyond the bottom of the window)
//		Else if it's visible, hide it
//			- set display style to "none"
//			- set image source to plus/expand graphic
//------------------------------------------------------------------
function toggle(id){
	section = document.getElementById(id);
	sectionImage = document.getElementById("img_"+id);
	main = document.getElementById("main_"+id);
	if (section.style.display == 'none'){
		section.style.display = "block";
		sectionImage.src = "/images/minus.gif";
		main_Ypos = findPosY(main);
		// If expanding the content block will result in it spilling off the page,
		// reset the page scroll so the bottom of the bio lands on the bottom of the page.
		// If the (block Y + block height) > (window Y + window height)
		// then, set Y scroll = bottom of the block - window height.
		if(document.all){
			if(ie7) {
				scrollTop = document.documentElement.scrollTop;
				offsetHeight = document.documentElement.offsetHeight;
			} else {
				scrollTop = document.body.scrollTop;
				offsetHeight = document.body.offsetHeight;
			}
			if((main_Ypos+main.offsetHeight)>=(scrollTop+offsetHeight)){
				window.scrollTo(0,main_Ypos+main.offsetHeight-offsetHeight+20);
				}
		}else {
			if((main_Ypos+main.offsetHeight)>=(window.pageYOffset+window.innerHeight)){
				window.scrollTo(0,main_Ypos+main.offsetHeight-window.innerHeight+20);
			}
		}
		// NOTE: If you want to just point to the top of the block, add a named anchor above
		// each block, and uncomment this assignment to set the browser position to the hash.
		//location.hash = 'a_'+id;
	}else{
		section.style.display = "none";
		sectionImage.src = "/images/plus.gif";
	}
}