var workTrays = [];
var currentWorkTray = 1;
var currentMenuItem = null;

function InitPage() {			
	for(var i = 1; i < 6; i++) {			
		 var trayID = 'work' + i;
		 workTrays[i] = document.getElementById(trayID);
										 
		 if(i == currentWorkTray) {				 
			displayWorkTray(workTrays[i], true);
		 } else {
			displayWorkTray(workTrays[i], false);
		 }
	}
	
	var menuItem = document.getElementById('workMenu1');
	
	if(menuItem) {
		selectMenuItem(menuItem);
	}
	
	displayWorkTray(document.getElementById('workTrayMenu'), true);
}		

function displayWorkTray(workTrayElem, toDisplay) {		
	if(workTrayElem) {			
		if(toDisplay) {				
			RemoveStyle(workTrayElem, 'hidden');
		} else {
			AddStyle(workTrayElem, 'hidden');
		}				
	}
}

function selectMenuItem(menuItem) {
	if(currentMenuItem) {
		RemoveStyle(currentMenuItem, 'selectedMenu')
	}
	
	AddStyle(menuItem, 'selectedMenu');
	
	currentMenuItem = menuItem;		
}

function displayWorkTrayByNum(workTrayNum, menuItem) {		
	displayWorkTray(workTrays[currentWorkTray], false);
	displayWorkTray(workTrays[workTrayNum], true);
	
	selectMenuItem(menuItem);
												
	currentWorkTray = workTrayNum;
}			

function highliteSubMenu(elem) {			
	AddStyle(elem, 'highliteMenu');			
}

function dehighliteSubMenu(elem) {
	RemoveStyle(elem, 'highliteMenu')
}

function AddStyle( item, style ) {
	if ( !item ) {
		return;
	}						
	if ( item.className ) {			
		var x = item.className.indexOf( style );
		if ( x < 0 ) {
			item.className += " " + style;
		}
	} else {
		item.className += " " + style;
	}
}
	
function RemoveStyle( item, style ) {
	if ( !item ) {
		return;
	}
	if ( !item.className ) {
		item.className = "";
	}
	var x = item.className.indexOf( style );
	var len = style.length;
	
	if ( x >= 0 ) {
		if ( item.className.substring( x - 1, 1 ) == " " ) {
			--x;		// take out the preceding space as well
			++ len;
		}
		item.className = item.className.substring( 0, x - 1 ) + 
							item.className.substring( x + len );
	}						
}