//args 1st = show, rest = hide
// to call function --> show_hide_layers(new Array(arg1,arg2,argN));

function show_hide_layers(a){

	document.getElementById(a[0]).style.visibility = "visible";
	
	for(var i=1;i<a.length;i++){
		document.getElementById(a[i]).style.visibility = "hidden";
	}
	
	
}

//hide submenus
function hidesubmenus(){

var layername

	layername = document.getElementById("Servicesmenu");
	layername.style.visibility = 'hidden';
	layername = document.getElementById("Activitiesmenu");
	layername.style.visibility = 'hidden';

}

// change page to newpage
function changePage(newpage){
	window.location = newpage;
}

//change text colour
function change_text_colour(src,c1){
var layername;

layername = document.getElementById(src);
layername.style.color = c1;
}

//change cursor to hand
function mOvr(src){ 
	src.style.cursor = 'pointer';
} 
//change cursor to default
function mOut(src){ 
	src.style.cursor = 'default';
}

function preloadimages(){
		leftarrowup       = new Image();
    		leftarrowup.src   = "pics/gallery/leftarrow1.jpg" ;
    		leftarrowdown     = new Image() ;
    		leftarrowdown.src = "pics/gallery/leftarrow.jpg" ;
		rightarrowup       = new Image();
    		rightarrowup.src   = "pics/gallery/rightarrow1.jpg" ;
    		rightarrowdown     = new Image() ;
    		rightarrowdown.src = "pics/gallery/rightarrow.jpg" ;
}

function preloadimages_dop(){
		leftarrowup       = new Image();
    		leftarrowup.src   = "pics/dop/nav/leftarrow1.jpg" ;
    		leftarrowdown     = new Image() ;
    		leftarrowdown.src = "pics/dop/nav/leftarrow.jpg" ;
		rightarrowup       = new Image();
    		rightarrowup.src   = "pics/dop/nav/rightarrow1.jpg" ;
    		rightarrowdown     = new Image() ;
    		rightarrowdown.src = "pics/dop/nav/rightarrow.jpg" ;
}

function preload_dop_images(){

	photo_buttonup       = new Image();
	photo_buttonup.src= "pics/dop/buttons/photo_buttondown.jpg"
	photo_buttondown      = new Image();
	photo_buttondown.src= "pics/dop/buttons/photo_buttonup.jpg"

	audio_buttonup       = new Image();
	audio_buttonup.src= "pics/dop/buttons/audio_buttondown.jpg"
	audio_buttondown      = new Image();
	audio_buttondown.src= "pics/dop/buttons/audio_buttonup.jpg"

	radio_buttonup       = new Image();
	radio_buttonup.src= "pics/dop/buttons/radio_buttondown.jpg"
	radio_buttondown      = new Image();
	radio_buttondown.src= "pics/dop/buttons/radio_buttonup.jpg"

	film_buttonup       = new Image();
	film_buttonup.src= "pics/dop/buttons/film_buttondown.jpg"
	film_buttondown      = new Image();
	film_buttondown.src= "pics/dop/buttons/film_buttonup.jpg"

	journal_buttonup       = new Image();
	journal_buttonup.src= "pics/dop/buttons/journal_buttondown.jpg"
	journal_buttondown      = new Image();
	journal_buttondown.src= "pics/dop/buttons/journal_buttonup.jpg"

	info_buttonup       = new Image();
	info_buttonup.src= "pics/dop/buttons/info_buttondown.jpg"
	info_buttondown      = new Image();
	info_buttondown.src= "pics/dop/buttons/info_buttonup.jpg"

}

function buttondown(buttonname)
{
	var imagename

	imagename = document.getElementById(buttonname);
	imagename.src = eval( buttonname + "down.src" );
}

function buttonup ( buttonname )
{
 	var imagename
	imagename = document.getElementById(buttonname);
	imagename.src = eval( buttonname + "up.src" );
}


function journalNav (week_no,direction)
{
	var week_displayed;
	var nextArrow;
	var prevArrow;
	var WeekLayerName;
	var weekString;

	nextArrow = document.getElementById("rightarrow");
	prevArrow = document.getElementById("leftarrow");
	
	for(var i=1;i<=week_no;i++){
		weekString = "week" + i;
		WeekLayerName = document.getElementById(weekString);

		if (WeekLayerName.style.visibility != "hidden")
		{
			week_displayed = i;
		}
		
	}	  		
	
	
	if (direction == "forward")
	{
		weekString = "week" + week_displayed;
		document.getElementById(weekString).style.visibility = "hidden";
		week_displayed = week_displayed + 1;
		weekString = "week" + week_displayed;		
		document.getElementById(weekString).style.visibility = "visible";

	}
	else
	{
		
		weekString = "week" + week_displayed;
		document.getElementById(weekString).style.visibility = "hidden";
		week_displayed = week_displayed - 1;
		weekString = "week" + week_displayed;		
		document.getElementById(weekString).style.visibility = "visible";
	
	}
	
	if (week_displayed == 1)
	{
		nextArrow.style.visibility = "visible";	
		prevArrow.style.visibility = "hidden";	
	}
	else if(week_displayed == week_no)
	{
		nextArrow.style.visibility = "hidden";	
		prevArrow.style.visibility = "visible";	
	}
	else
	{
		nextArrow.style.visibility = "visible";	
		prevArrow.style.visibility = "visible";	
	}
}