function calc_position(popWidth, popHeight) {
	popLeft = (screen.width/2)-(popWidth/2);
	popTop = (screen.height/2)-(popHeight/2);
	var returnRay = new Array(popWidth, popHeight, popLeft, popTop);
	return returnRay;
}

function forum_edit_window(action, id, label, forum, width, height) {
	var link = '/popup/forum.php?action='+action+'&i_id='+id+'&i_label='+label;
	if(forum!='') {
		link+= '&i_forum='+forum;
	}
	
	if(width==undefined) width = 300;
	if(height==undefined) height = 100;
	
	popProps = calc_position(width, height);
	window.open(link, 'forumPopup', 'scrollbars=no, width='+popProps[0]+', height='+popProps[1]+', left='+popProps[2]+', top='+popProps[3]);
}

/*
* Forum reactie formulier toon verberg code
*/
function forumreactieForm_submit() {
	var form=document.getElementById('forumreactieForm');
    if(form.style.display == 'none') {
		form.style.display = 'block';
		window.scroll(0,form.offsetTop);
	} else if (form.style.display == 'block') {
	    var fields = form.elements;
	    var form_errors=document.getElementById('forumformErrors');
	    form_errors.innerHTML='';
	    var do_submit=true;
        for(var i=0;i<fields.length;i++) {
           var field=fields[i];
	       if(field.type=='hidden') continue;
	       var regex = /^[\w\.-]+@[\w\.-]+\.[a-zA-Z]{2,3}$/;
           if(field.value=='' || (field.name=='email' && !regex.test(field.value))) {
                form_errors.innerHTML+=field.title+' is verplicht om in te vullen<br />';
                do_submit=false;
           }
        }
        if(do_submit) {
            form.submit();
        }
	}
}
function cancelforumreactieForm() {
    var form=document.getElementById('forumreactieForm');
	form.reset();
	form.style.display = 'none';
	return false;
}

/*
* Forum functions
*/

function ToggleForum(id,obj) { 
	if(document.getElementById('ForumCat'+id).style.display == 'none') {
		document.getElementById('ForumCat'+id).style.display = 'block';
		document.getElementById('ForumCat'+id+'_OC').innerHTML = '-';
	} else if(document.getElementById('ForumCat'+id).style.display == 'block') {
		document.getElementById('ForumCat'+id).style.display = 'none';
		document.getElementById('ForumCat'+id+'_OC').innerHTML = '+';
	}
	obj.blur();
	return false;
}