var zoom_factor = 1;

var ZOOM_MIN 		= 1;
var ZOOM_MAX		= 2.5;


/**
 * Writes the zoom with the specified factor.
 */
/*void*/ function ingrease(intFactor)
{
	if (!intFactor)
		return;

	// is internet explorer
	if (document.all && document.getElementById)
	{
		// save zoom factor
		var newZoom = zoom_factor;

		if (intFactor < 0)
		{
			newZoom /= Math.abs(intFactor);
		}
		else
		{
			newZoom *= intFactor;
		}

		// assign new zoom if it is valid
		if (newZoom >= ZOOM_MIN && newZoom <= ZOOM_MAX)
		{
			document.body.style.zoom = zoom_factor = newZoom;
		}
	}
}
function hide(arr){
	//var isactive = document.getElementById(id).checked;
	//if(isactive == true){
		var usealert = 'no';
		var messagetext = '';
		if(arr !=''){
			alleboxen = arr.split(',');
			for(i = 0; i < alleboxen.length; i++){
				if(document.getElementById(alleboxen[i]).checked == true){
					usealert = 'yes';
					messagetext = messagetext + '\"' + document.getElementById(alleboxen[i]).title + '\"\n';
					document.getElementById(alleboxen[i]).checked = false;			
				}		
			} 
			if(usealert == 'yes'){
				//alert('Attention!\nBy clicking this item, previous selections will be changed!\nPlease check for changes!');
				alert('Attention!\nBy clicking this item, following item(s) will be changed:\n' + messagetext + '\nPlease check for changes!');
			}
		}
	//}
}
function show(arr,clkbox){
	if(arr !=''){
		var checkstatus = false;
		var messagetext = '';
		alleboxen = arr.split(',');
		for(i = 0; i < alleboxen.length; i++){
			if(document.getElementById(alleboxen[i]).checked == true){
				checkstatus = true;
			}else{
			if(messagetext !=''){
			messagetext = messagetext + 'or\n';
			}
			messagetext = messagetext + '\"' + document.getElementById(alleboxen[i]).title + '\"\n';	
			
			}
		}//loop
		if(checkstatus != true){
			var answer = alert("Previous selection must be\n" + messagetext + "\nbefore you can select this item!");
			document.getElementById(clkbox).checked = false;
		}			
	}//arr !=''
}


function gebucht(id){
	if(id != ''){
		alert('Sie haben diese Veranstaltung bereits gebucht!');
		document.getElementById(id).checked = false;
	}
}
function voll(id){
	if(id != ''){
		alert('Diese Veranstaltung ist bereits ausgebucht!');
		document.getElementById(id).checked = false;
	}
}

function sw(id){
	var elem = document.getElementById(id);
	if(elem.style.display=='none'){
		elem.style.display='block';
	}else{
		elem.style.display='none';	
	}
}

function spezialscript(id){
	usealerter = 'no';
	if(id == 53){
		usealerter = 'yes';
	}
	if(id == 33){
		usealerter = 'yes';	
	}
	if(id == 54){
		usealerter = 'yes';	
	}
	if(usealerter == 'yes'){
		if(document.getElementById(id).checked == true){
			alert('Please indicate the number of persons!');
		}
	}
}