function is_catswitch(cat,force) {
	currentstate = document.getElementById('category_' + cat + '_container').style.display == 'none' ? 'closed' : 'open';
	
	if(currentstate == 'closed' || force == 'open') {
		document.getElementById('category_' + cat + '_switch').src = 'http://static.gameparty.net/sitegfx/inschrijf/open.gif';
		document.getElementById('category_' + cat + '_container').style.display = '';
		document.getElementById('category_' + cat + '_switch').value = ' - ';
		document.getElementById('category_' + cat + '_switch').alt = txt_items_closecategory;
	} else if(currentstate == 'open' || force == 'close') {
		document.getElementById('category_' + cat + '_switch').src = 'http://static.gameparty.net/sitegfx/inschrijf/closed.gif';
		document.getElementById('category_' + cat + '_container').style.display = 'none';
		document.getElementById('category_' + cat + '_switch').value = ' + ';
		document.getElementById('category_' + cat + '_switch').alt = txt_items_opencategory;
	}
}

function is_itemswitch(item,force) {
	currentstate = document.getElementById('item_' + item + '_container').style.display == 'none' ? 'closed' : 'open';
	
	if(currentstate == 'closed' || force == 'open') {
		document.getElementById('item_' + item + '_switch').src = 'http://static.gameparty.net/sitegfx/inschrijf/open.gif';
		document.getElementById('item_' + item + '_container').style.display = '';
		document.getElementById('item_' + item + '_switch').value = ' - ';
		document.getElementById('item_' + item + '_switch').alt = txt_items_closeitem;
	} else if(currentstate == 'open' || force == 'close') {
		document.getElementById('item_' + item + '_switch').src = 'http://static.gameparty.net/sitegfx/inschrijf/closed.gif';
		document.getElementById('item_' + item + '_container').style.display = 'none';
		document.getElementById('item_' + item + '_switch').value = ' + ';
		document.getElementById('item_' + item + '_switch').alt = txt_items_openitem;
	}
}

function is_buy(itemid) {
	type = document.getElementById('item_' + itemid + '_input').type == 'checkbox' ? 'boolean' : 'integer';
	
	if(type == 'integer') {
		value = document.getElementById('item_' + itemid + '_input').value;
		if(value != '' && parseInt(value) != value) {
			alert(txt_items_error_js_integer);
			document.getElementById('item_' + itemid + '_input').value = '';
		}
	}
	
	return true;
}

function is_groupbuy(itemid,userid) {
	type = document.getElementById('item_' + itemid + '_input[' + userid + ']').type == 'checkbox' ? 'boolean' : 'integer';
	
	if(type == 'boolean') {
		if(userid == 'all') {
			for(j in userids) {
				document.getElementById('item_' + itemid + '_input[' + userids[j] + ']').checked = document.getElementById('item_' + itemid + '_input[all]').checked;
			}
		} else {
			if(document.getElementById('item_' + itemid + '_input[all]').checked == true && document.getElementById('item_' + itemid + '_input[' + userid + ']').checked == false) {
				document.getElementById('item_' + itemid + '_input[all]').checked = false;
			}
		}
	} else if(type == 'integer') {
		value = document.getElementById('item_' + itemid + '_input[' + userid + ']').value;
		if(value != '' && parseInt(value) != value) {
			alert(txt_items_error_js_integer);
			document.getElementById('item_' + itemid + '_input[' + userid + ']').value = '';
		} else {
			if(userid == 'all') {
				for(j in userids) {
					document.getElementById('item_' + itemid + '_input[' + userids[j] + ']').value = value;
				}
			}
		}
	}
}

function is_makevisible(type,id) {
	if(type == 'cat') {
		is_catswitch(id,'open');
	} else if(type == 'item') {
		is_makevisible('cat',item2cat[id]);
		is_itemswitch(id,'open');
	}
}

function groupmember_add_fromlist() {
	var boxLength = document.isform['users[]'].length;
	var selectedItem = document.isform['users_available[]'].selectedIndex;
	if(selectedItem != -1) {
		var selectedText = document.isform['users_available[]'].options[selectedItem].text;
		var selectedValue = document.isform['users_available[]'].options[selectedItem].value;
		newoption = new Option(selectedText, selectedValue, false, false);
		document.isform['users[]'].options[boxLength] = newoption;
		document.isform['users_available[]'].options[selectedItem]=null;
		document.isform.groupmember_add_fromlist_button.disabled = true;
	} else {
		alert(txt_group_error_js_memberadd);
	}
}

function check_freefield() {
	if(document.isform['users_free'].value.length < 1) {
		alert(txt_group_error_js_freeadd);
		return false;
	} else {
		return true;
	}
}

function selectall() {
	if (document.isform['users[]'].length != 0) {
		for (i = 0; i < document.isform['users[]'].length; i++) {
			document.isform['users[]'].options[i].selected = true;
		}
	}
	
	if (document.isform['users_available[]'].length != 0) {
		for (i = 0; i < document.isform['users_available[]'].length; i++) {
			document.isform['users_available[]'].options[i].selected = true;
		}
	}
	
}

function groupmember_add_free_onkeydown(e) {
	var key = (navigator.appName == 'Netscape') ? e.which : e.keyCode;
	if (key == 13) groupmember_add_free_submit();
}


function groupmember_del() {
	var boxLength = document.isform['users_available[]'].length;
	var selectedItem = document.isform['users[]'].selectedIndex;
	if(selectedItem != -1) {
		var selectedText = document.isform['users[]'].options[selectedItem].text;
		var selectedValue = document.isform['users[]'].options[selectedItem].value;
	
		if(selectedText != username || selectedValue != userid) {
			newoption = new Option(selectedText, selectedValue, false, false);
			document.isform['users_available[]'].options[boxLength] = newoption;
			document.isform['users[]'].options[selectedItem]=null;
			document.isform.groupmember_del_button.disabled = true;
		} else {
			alert(txt_group_error_js_selfdelete);
		}
	} else {
		alert(txt_group_error_js_memberdel);
	}
}

function doonsubmit() {
	if(document.isform['users[]'].length == 0) {
		alert(txt_group_error_js_nomembers);
		return false;
	} else if(document.isform['users[]'].length == 1) {
		for (i = 0; i < document.isform['users[]'].length; i++) {
			id = document.isform['users[]'].options[i].value;
		}
		
		if(id == userid && mode == 'register') {
			alert(txt_group_error_js_useronlymember);
		} else if(id != userid) {
			alert(txt_group_error_js_selfdelete);
		} else if(mode == 'registration') {
			selectall();
			return true;
		}
		return false;
	} else {
		selectall();
		return true;
	}
}

function helpitem(title, content, height) {
	win = window.open('about:blank', 'is_help', 'width=300,height=' + height + ',status=no,toolbar=no,menubar=no,menubar=no');
	d = win.document;
	d.write('<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><link rel="stylesheet" href="http://static.gameparty.net/css/inschrijf.css" media="screen" type="text/css"><title>Help: ' + title + '</title></head><body class="is_overzicht"><div class="is_main">');
	d.write('<table width="100%" class="is_inset"><tr><th>' + title + '</th></tr><tr><td>' + content + '</td></tr></table>');
	d.write('<table width="100%" class="is_inset"><tr><td align="center"><button type="button" onClick="top.close()">Sluiten</button></td></tr></table>');
	d.write('</table>');
	d.write('</div></body></html>');
}