function toggle_hidden(box_id)
{
  if (document.getElementById(box_id).className=='commentshidden') {
    document.getElementById(box_id).className='commentsshow'
 } else {
    document.getElementById(box_id).className='commentshidden'
  }
}

function stat_write(name,at)
{
  window.status='mailto:'+name+'@'+at;
}

function stat_write_blank()
{
  window.status='';
}

function email(name,at)
{
  location.href='mailto:'+name+'@'+at
}

function update_info(layer,url) {
  update(layer,url);
  change_tab(5);
}

function update(layer,url) {
  document.getElementById(layer).innerHTML='<p><i>Loading Page...</i></p>';
  xmlhttp.open("GET",url,true);
  xmlhttp.onreadystatechange=function() {
   if (xmlhttp.readyState==4) {
    document.getElementById(layer).innerHTML=xmlhttp.responseText;
   }
  }
 xmlhttp.setRequestHeader('Accept','message/x-formresult')
 xmlhttp.send(null)
 return false
}

function filter() {
   map.clearOverlays();
   if (document.filter_form.marker1.checked == true) {  filtered_overlay(1, 0); }
   if (document.filter_form.marker2.checked == true) {  filtered_overlay(2, 0); }
   if (document.filter_form.marker3.checked == true) {  filtered_overlay(3, 0); }
   if (document.filter_form.marker4.checked == true) {  filtered_overlay(4, 0); }
   if (document.filter_form.marker5.checked == true) {  filtered_overlay(5, 0); }
   if (document.filter_form.marker6.checked == true) {  filtered_overlay(6, 0); }
   if (document.filter_form.marker7.checked == true) {  filtered_overlay(7, 0); }
   if (document.filter_form.marker8.checked == true) {  filtered_overlay(8, 0); }
   if (document.filter_form.marker9.checked == true) {  filtered_overlay(9, 0); }
   if (document.filter_form.marker10.checked == true) {  filtered_overlay(10, 0); }
   if (document.filter_form.marker11.checked == true) {  filtered_overlay(11, 0); }
}
     
function filtered_overlay(cat, zoom) {
   var file = "route_data_" + cat + ".xml"
   GDownloadUrl(file, function(data, responseCode) {
      var xml = GXml.parse(data);
      var markers = xml.documentElement.getElementsByTagName("marker");
      for (var i = 0; i < markers.length; i++) {
         var point = new GLatLng(parseFloat(markers[i].getAttribute("lat")),
                                 parseFloat(markers[i].getAttribute("lng")));
         map.addOverlay(createMarker(point, markers[i].getAttribute("name"), markers[i].getAttribute("length"), markers[i].getAttribute("link"), markers[i].getAttribute("cmts"), markers[i].getAttribute("id"), markers[i].getAttribute("cat")));
         if ((zoom == 1) && (markers[i].getAttribute("id") == "<?=$route?>"))
         {
            map.setCenter(point, 12);
            map.openInfoWindowHtml(point,get_info_text(markers[i].getAttribute("id"), markers[i].getAttribute("name"), markers[i].getAttribute("length"), markers[i].getAttribute("link"), markers[i].getAttribute("cmts")));
            update('comments','http://www.fogma.co.uk/mtb_routes/comments/<?=$route?>');
         }
      }
   });
}

function change_tab(tab_number) {
  var content_name = "content_" + tab_number;
  var tab          = "tab_" + tab_number
  document.getElementById("content_1").className = 'hide_tab';
  document.getElementById("content_2").className = 'hide_tab';
  document.getElementById("content_3").className = 'hide_tab';
  document.getElementById("content_4").className = 'hide_tab';
  document.getElementById("content_5").className = 'hide_tab';
  
  document.getElementById("tab_1").className = 'unselected';
  document.getElementById("tab_2").className = 'unselected';
  document.getElementById("tab_3").className = 'unselected';
  document.getElementById("tab_4").className = 'unselected';
  document.getElementById("tab_5").className = 'unselected';
  
  document.getElementById(content_name).className='show_tab';
  document.getElementById(tab).className='selected';
}

    
function openinfowindow(i) {
//    map.setCenter(centres[i], 12);
    gmarkers[i].openInfoWindowHtml(htmls[i]);
}