//========================================================
// Chained select menus
//========================================================

function dynamicSelect(id1, id2) {
	// Feature test to see if there is enough W3C DOM support
	if (document.getElementById && document.getElementsByTagName) {
		// Obtain references to both select boxes
		var sel1 = document.getElementById(id1);
		var sel2 = document.getElementById(id2);
		// Clone the dynamic select box
		var clone = sel2.cloneNode(true);
		// Obtain references to all cloned options 
		var clonedOptions = clone.getElementsByTagName("option");
		// Onload init: call a generic function to display the related options in the dynamic select box
		refreshDynamicSelectOptions(sel1, sel2, clonedOptions);
		// Onchange of the main select box: call a generic function to display the related options in the dynamic select box
		sel1.onchange = function() {
			refreshDynamicSelectOptions(sel1, sel2, clonedOptions);
		};
	}
}
function refreshDynamicSelectOptions(sel1, sel2, clonedOptions) {
	// Delete all options of the dynamic select box
	while (sel2.options.length) {
		sel2.remove(0);
	}
	// Create regular expression objects for "select" and the value of the selected option of the main select box as class names
	var pattern1 = /( |^)(select)( |$)/;
	var pattern2 = new RegExp("( |^)(" + sel1.options[sel1.selectedIndex].value + ")( |$)");
	// Iterate through all cloned options
	for (var i = 0; i < clonedOptions.length; i++) {
		// If the classname of a cloned option either equals "select" or equals the value of the selected option of the main select box
		if (clonedOptions[i].className.match(pattern1) || clonedOptions[i].className.match(pattern2)) {
			// Clone the option from the hidden option pool and append it to the dynamic select box
			sel2.appendChild(clonedOptions[i].cloneNode(true));
		}
	}
}


//========================================================
// DOM script for expand collapse divs
//========================================================


function expandFirst() {
			document.getElementById(expandFirst.arguments[0]).style.display = "block";
			for (var i=1; i<expandFirst.arguments.length; i++) {
				document.getElementById(expandFirst.arguments[i]).style.display = "none";
			}
		}
function expandCollapse() {
	for (var i=0; i<expandCollapse.arguments.length; i++) {
		var element = document.getElementById(expandCollapse.arguments[i]);
		element.style.display = (element.style.display == "none") ? "block" : "none";
	}
}


//========================================================
// DOM script for mouseovers on adtech advertisements
//========================================================


function show_advert(info) {
	document.getElementById("adplaceholder").style.display = "none";
	document.getElementById("info"+info).style.display = "block";
}

function hide_advert_advert_advert(info) {
	document.getElementById("adplaceholder").style.display = "block";
	document.getElementById("info"+info).style.display = "none";
}

function hide_advert(info) {
	document.getElementById("adplaceholder").style.display = "block";
	document.getElementById("info"+info).style.display = "none";
}

//========================================================
// DOM script for picture gallery
//========================================================

function showPic(whichpic) {
  if (!document.getElementById("placeholder")) return true;
  var source = whichpic.getAttribute("href");
  var placeholder = document.getElementById("placeholder");

  placeholder.setAttribute("src",source);
  if (!document.getElementById("picdescription")) return false;
  if (whichpic.getAttribute("title")) {
    var text = whichpic.getAttribute("title");
  } else {
    var text = "";
  }
  var description = document.getElementById("picdescription");
  if (description.firstChild.nodeType == 3) {
    description.firstChild.nodeValue = text;
  }
  return false;
}

function prepareGallery() {
  if (!document.getElementsByTagName) return false;
  if (!document.getElementById) return false;
  if (!document.getElementById("imagegallery")) return false;
  var gallery = document.getElementById("imagegallery");
  var links = gallery.getElementsByTagName("a");
  for ( var i=0; i < links.length; i++) {
    links[i].onclick = function() {
      return showPic(this);
	}
    links[i].onkeypress = links[i].onclick;
  }
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

addLoadEvent(prepareGallery);