var overlayActive = 0;

function activateOverlayControl(id, rel) {
	var overlayImage = document.getElementById('overlay_image');
	var overlayTitle = document.getElementById('overlay_title');
	
	overlayImage.src = 'images/stones/' + id + '_lrg.jpg';
	overlayImage.setAttribute('alt', rel + ' Large');
	overlayImage.setAttribute('title', rel);
	overlayTitle.innerHTML = rel;
	/*
	document.getElementById('overlay_image').src = 'images/stones/' + thisiD + '_lrg.jpg';
	document.getElementById('overlay_title').innerHTML = thisiD;
	*/
	var berkoBox = document.getElementById('berkobox');
	berkoBox.onclick = function() {
		window.event.cancelBubble = true;
	};
	
	var overlayControl = document.getElementById('overlay_control');
	var selectionImage = document.getElementById('selection_image');
	
	selectionImage.onmouseover = function() {
		this.style.cursor = 'pointer';
	};
	
	selectionImage.onclick = function() {
		activateOverlay();
		return false;
	};
	
	overlayControl.onclick = function() {
		activateOverlay();
		return false;
	};
}

function activateOverlay() {
	overlayActive = 1;
	var overlay = document.getElementById('overlay');
	overlay.style.display = 'block';
	overlay.style.width = '100%';
	overlay.style.height = '100%';
	setTimeout("showOverlay()", 250);
}

function showOverlay() {
	var animOverlay = new YAHOO.util.Anim('berkobox', { height: {to: 525}}, .350, YAHOO.util.Easing.easeIn);
	animOverlay.onComplete.subscribe(activateCloseControl);
	animOverlay.animate();
}

function activateCloseControl() {
	var overlayClose = document.getElementById('overlay_close');
	overlayClose.onclick = function() {
		hideOverlay();
		return false;
	};
	
	var overlay = document.getElementById('overlay');
	overlay.onclick = function() {
		hideOverlay();
		return false;
	};
	
	var arVersion = navigator.appVersion.split("MSIE");
	var version = parseFloat(arVersion[1]);
	if ((version >= 5.5 && version < 7) && (document.body.filters)) {
		window.onresize = function() {
			var overlay = document.getElementById('overlay');
			overlay.style.width = '100%';
			overlay.style.height = '100%';
		};
		
		window.onscroll = function() {
			var overlay = document.getElementById('overlay');
			overlay.style.top = getScrollY();
			overlay.style.height = getHeight();
		};
	}

	
}

function hideOverlay() {
	var animOverlay = new YAHOO.util.Anim('berkobox', { height: {to: 0}}, .250, YAHOO.util.Easing.easeIn);
	animOverlay.onComplete.subscribe(removeOverlay);
	animOverlay.animate();
}

function removeOverlay() {
	var overlay = document.getElementById('overlay');
	overlay.style.display = 'none';
	overlayActive = 0;
}

function getScrollY() {
  var scrOfY = 0;
  if( typeof( window.pageYOffset ) == 'number' ) {
    scrOfY = window.pageYOffset;
  } else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
    scrOfY = document.body.scrollTop;
  } else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
    scrOfY = document.documentElement.scrollTop;
  }
  return scrOfY;
}

function getHeight() {
  var myHeight = 0;
  if( typeof( window.innerWidth ) == 'number' ) {
    myHeight = window.innerHeight;
  } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
    myHeight = document.documentElement.clientHeight;
  } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
    myHeight = document.body.clientHeight;
  }
  return myHeight;
}