// DOCUMENTATION //////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Toto je nabidkova lista s polozkami ve forme obrazku. Zvyraznuje aktualni polozku a polzoku pdo mysi.
// Pro pouziti je potreba:
// - zalozit menu: var Menu = new TMenu("Menu", ...);
// - pridat do menu polozky: Menu.Add(...);
// - mit obrazky, jejich nazvy jsou odvozene od jmena polozky
// - mit v dokumentu elementy, kam se obrazky vlozi, jejich nazvy jsou odvozene od jmena polozky
// - v OnLoad dokumentu zavolat Menu.Run();
// - ridit vybraznou polozku pomoci Menu.Select() nebo Menu.Synchronize()


 // FUNCTIONS //////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function SameURL(urlA, urlB) {
   // porovnani koncu stringu
  var len = Math.min(urlA.length, urlB.length);
  return (len > 0) && (urlA.slice(urlA.length - len) == urlB.slice(urlB.length - len));
  };
  

 // CLASS TMenu ////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 // PUBLIC CLASS MEMBERS
function TMenu(name, target, elementPrefix, elementSuffix, imagePrefix, imageSuffix) {
   // public metody
  this.Add = TMenu_Add;
  this.Run = TMenu_Run;
  this.Synchronize = TMenu_Synchronize;
  this.Select = TMenu_Select;
  this.Hilight = TMenu_Hilight;
   // private metody
  this.find = TMenu_find;
   // inicializace poli
  this.name = name; 
  this.target = target;
  this.elementPrefix = elementPrefix;
  this.elementSuffix = elementSuffix;
  this.imagePrefix = imagePrefix;
  this.imageSuffix = imageSuffix;
  this.items = new Array();                             
  this.itemSelected = null;
  this.itemHilighted = null;
  };
  
function TMenu_Add(name, caption, url, target) {
   // pridani polozky do seznamu
  index = this.items.length;
  this.items[index] = new TMenuItem(this, name, caption, url, target);
  };
  
function TMenu_Run() {
   // pro vsechny polozky menu
  for (var i = 0; i < this.items.length; i++)
    this.items[i].build();
  };
    
function TMenu_Synchronize() {
   // urceni dokumentu v cilovem okne
  var frame = window.frames[this.target];
  var url = frame ? frame.document.URL :"";
   // vyhledani polozky menu se stejnou URL
  var selectItem = null;
  for (var i = 0; (i < this.items.length) && !selectItem; i++)
    selectItem = SameURL(this.items[i].url, url) ? this.items[i] : null;
   // vybrani odpovidajici polozky
  this.Select(selectItem ? selectItem.name : ""); 
  };
   
function TMenu_Select(selected) {
   // nastaveni vybrane polozky
  var prevSelected = this.itemSelected; 
  this.itemSelected = this.find(selected);
  if (this.itemSelected != prevSelected) {
    if (prevSelected) prevSelected.update();
    if (this.itemSelected) this.itemSelected.update();
    };
  };

function TMenu_Hilight(hilighted) {
   // nastaveni podbarvene polozky
  var prevHilighted = this.itemHilighted; 
  this.itemHilighted = this.find(hilighted);
  if (this.itemHilighted != prevHilighted) {
    if (prevHilighted) prevHilighted.update();
    if (this.itemHilighted) this.itemHilighted.update();
    };
  };
  
 // PRIVATE CLASS MEMBERS
function TMenu_find(name) {
   // prednastaveni navratove hodnoty
  var result = null;
   // vyhledani id
  for (var i = 0; !result && (i < this.items.length); i++) 
    result = (name == this.items[i].name) ? this.items[i] : null;
   // navratova hodnota
  return result;
  };
    
 // EVENT HANDLERS
function TMenu_mouseOverHandler() {
  eval(this.getAttribute("mouseOverHandler"));
  };
  
function TMenu_mouseOutHandler() {
  eval(this.getAttribute("mouseOutHandler"));
  };
  
function TMenu_loadHandler() {
  alert("Je to tady");
  // eval(this.getAttribute("loadHandler"));
  };


 // CLASS TMenuItem ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 // PUBLIC CLASS MEMBERS
function TMenuItem(menu, name, caption, url) {
   // public metody
  this.Width = TMenuItem_Width; 
  this.Height = TMenuItem_Height; 
   // private metody
  this.build = TMenuItem_build;
  this.update = TMenuItem_update;
   // inicializace poli
  this.menu = menu; 
  this.name = name;
  this.caption = caption;
  this.imageN = new Image;
  this.imageN.src = this.menu.imagePrefix + name + "N" + this.menu.imageSuffix;
  this.imageA = new Image;
  this.imageA.src = this.menu.imagePrefix + name + "A" + this.menu.imageSuffix;
  this.url = url;
  this.elemAnchor = null;
  this.elemImage = null;
  };
  
function TMenuItem_Width() {
   // velikost by mela byut shodna
  return Math.max(this.imageN.width, this.imageA.width);
  };

function TMenuItem_Height() {
   // velikost by mela byt shodna
  return Math.max(this.imageN.height, this.imageA.height);
  };
  
 // PRIVATE CLASS MEMBERS
function TMenuItem_build() {
   // nalezeni odpovidajiciho umisteni 
  var elemParent = document.getElementById(this.menu.elementPrefix + this.name + this.menu.elementSuffix);
  if (elemParent) {
     // vytvoreni odkazu
    this.elemAnchor = document.createElement("A");
    this.elemAnchor.href = this.url;
    this.elemAnchor.target = this.menu.target;
    this.elemAnchor.onmouseover = TMenu_mouseOverHandler;
    this.elemAnchor.setAttribute("mouseOverHandler", this.menu.name + ".Hilight('" + this.name + "')");
    this.elemAnchor.onmouseout = TMenu_mouseOutHandler;
    this.elemAnchor.setAttribute("mouseOutHandler", this.menu.name + ".Hilight('')");
     // vytvoreni obrazku
    this.elemImage = document.createElement("IMG");
    // this.elemImage.src = this.imageN.src;
    this.elemImage.width = this.Width();
    this.elemImage.height = this.Height();
    this.elemImage.alt = this.caption;
     // vlozeni elementu
    this.elemAnchor.appendChild(this.elemImage);
    elemParent.appendChild(this.elemAnchor);
    };
   // nastaveni obrazku dle aktivity
  this.update(); 
  };
  
function TMenuItem_update() {
   // prepinani obrazku dle aktivity
  if (this.elemImage)
    if ((this.menu.itemSelected == this) || (this.menu.itemHilighted == this))
      this.elemImage.src = this.imageA.src
    else 
      this.elemImage.src = this.imageN.src;
  };