/* 
   * Fügt den Listeneinträgen Eventhandler und CSS Klassen hinzu,
   * um die Menüpunkte am Anfang zu schließen.
   * 
   * menu: Referenz auf die Liste.
   * data: String, der die Nummern aufgeklappter Menüpunkte enthält.
   */
  function treeMenu_init(menu) {
	  var selected_node = null;
    var array = new Array(0);
    var items = menu.getElementsByTagName("li");
		var opend = false;
    for (var i = 0; i < items.length; i++) {
      items[i].onclick = treeMenu_handleClick;
			if (selected_node == null) {
				var anchors = items[i].getElementsByTagName("a");
				if (anchors.length>0) {
					for (var k = 0; k < anchors.length; ++k) {
					  var classes_ = treeMenu_getClasses(anchors[k]);
						if (treeMenu_contains(classes_, "selected")) {
							selected_node = anchors[k];
							break;
						}
					}
				}
			}
			var classes = treeMenu_getClasses(items[i]);
			opend = treeMenu_contains(classes, "treeMenu_opened");
			opend = opend || treeMenu_contains(classes, "selected");
      if (!opend
          && items[i].getElementsByTagName("ul").length
            + items[i].getElementsByTagName("ol").length > 0) {
				
        if (array.length > 0 && array[0] == i) {
          classes.push("treeMenu_opened")
        }
        else {
          classes.push("treeMenu_closed")
        }
        items[i].className = classes.join(" ");
        if (array.length > 0 && array[0] == i) {
          array.shift();
        }
      }
    }
		treeMenu_selectTree(selected_node);
		var root = document.getElementById("tree_root");
		classes = treeMenu_getClasses(root);		
		for (var i = 0; i < classes.length; i++) {
		  if (classes[i] == "closed") {
        classes[i] = "opened";
				break;
      }
		}
		root.className = classes.join(" ");
  }

function treeMenu_selectTree(leaf) {
  var item = leaf;
	while (item) {
		var array = treeMenu_getClasses(item);
		for (var i = 0; i < array.length; i++) {
			if (array[i] == "treeMenu_closed") {
				array[i] = "treeMenu_opened";
			}
		}
		if (item.nodeName.toLowerCase() == "li") {
			var anchors = item.getElementsByTagName("a");
			if (anchors.length > 0) {
				for (var k = 0; k < anchors.length; ++k) {
					if (item.firstChild != anchors[k]) {
						continue;
					}

					var classes_ = treeMenu_getClasses(anchors[k]);
					if (!treeMenu_contains(classes_, "selected")) {
						classes_.push("selected");
						anchors[k].className = classes_.join(" ");
						break;
					}
				}
			}
		}
		item.className = array.join(" ");
		item = item.parentNode;
	}
}
	
  function treeMenu_closeAll(thisNot) {
    var items = menu.getElementsByTagName("li");
    for (var k = 0; k < items.length; k++) {
      if (items[k] == thisNot) {
        continue;
      }
      var array = treeMenu_getClasses(items[k]);
      for (var i = 0; i < array.length; i++) {
        if (array[i] == "treeMenu_opened") {
          array[i] = "treeMenu_closed";
        }
      }
      items[k].className = array.join(" ");
    }
  }
  
  /*
   * Ändert die Klasse eines angeclickten Listenelements, sodass
   * geöffnete Menüpunkte geschlossen und geschlossene geöffnet
   * werden.
   *
   * event: Das Event Objekt, dass der Browser übergibt.
   */
  function treeMenu_handleClick(event) {
    if (event == null) { //Workaround für die fehlenden DOM Eigenschaften im IE
      event = window.event;
      event.currentTarget = event.srcElement;
      while (event.currentTarget.nodeName.toLowerCase() != "li") {
        event.currentTarget = event.currentTarget.parentNode;
      }
      event.cancelBubble = true;
    }
    else {
      event.stopPropagation();
    }
    //treeMenu_closeAll(event.currentTarget);
    var array = treeMenu_getClasses(event.currentTarget);
    for (var i = 0; i < array.length; i++) {
      if (array[i] == "treeMenu_closed") {
        array[i] = "treeMenu_opened";
				break;
      }
      else if (array[i] == "treeMenu_opened") {
        array[i] = "treeMenu_closed";
				break;
      }
    }
    event.currentTarget.className = array.join(" ");
		treeMenu_selectTree(event.currentTarget);
  }
  
  /*
   * Gibt alle Klassen zurück, die einem HTML-Element zugeordnet sind.
   * 
   * element: Das HTML-Element
   * return: Die zugeordneten Klassen.
   */
  function treeMenu_getClasses(element) {
    if (element.className) {
      return element.className.match(/[^ \t\n\r]+/g);
    }
    else {
      return new Array(0);
    }
  }
  
  /*
   * Überprüft, ob ein Array ein bestimmtes Element enthält.
   * 
   * array: Das Array
   * element: Das Element
   * return: true, wenn das Array das Element enthält.
   */
  function treeMenu_contains(array, element) {
    for(var i = 0; i < array.length; i++) {
      if(array[i] == element) {
        return true;
      }
    }
    return false;
  }
  
  /*
   * Gibt einen String zurück, indem die Nummern aller geöffneten
   * Menüpunkte stehen. 
   *
   * menu: Referenz auf die Liste
   * return: Der String
   */
  function treeMenu_store(menu) {
    var result = new Array();
    var items = menu.getElementsByTagName("li");
    for (var i = 0; i < items.length; i++) {
      if (treeMenu_contains(treeMenu_getClasses(items[i]), "treeMenu_opened")) {
        result.push(i);
      }
    }
    return result.join(" ");
  }