var tijd_verschil = new Array();

function refresh_clock() 
{ 

	// verhoog server tijd met 1 seconde
	server_time++;

	for (var i = 0; i < tijd_verschil.length; i++)
	{
		tijd_verschil[i][1] -= 1000;
		
		var diff = tijd_verschil[i][1];
		
		var id = tijd_verschil[i][0];

		if ((diff <= 0) || (Math.floor(diff/1000) == 60))
		{
			window.location.reload();
		}
		else
		{
			var dagen = Math.floor(diff/1000/60/60/24);
			diff -= dagen*1000*60*60*24;
			var uren = Math.floor(diff/1000/60/60);
			diff -= uren*1000*60*60;
			var minuten = Math.floor(diff/1000/60);
			diff -= minuten*1000*60;
			var seconden = Math.floor(diff/1000);

			if ((uren > 0) || (dagen > 0))
				uren = '<strong> '+uren+'</strong>h';
			else
				uren = '';
			minuten = '<strong> '+minuten+'</strong>m';
			seconden = '<strong> '+seconden+'</strong>s';
			if (dagen > 0)
				dagen = '<strong> '+dagen+'</strong>d';
			else
				dagen = '';

			document.getElementById('timer_'+id).innerHTML = dagen+uren+minuten+seconden; 
		}
	}
}