// This function is used to define if the browser supports the needed
// features
function hasSupport() {

  if (typeof hasSupport.support != "undefined")
    return hasSupport.support;
  
  var ie55 = /msie 5\.[56789]/i.test( navigator.userAgent );
  
  hasSupport.support = ( typeof document.implementation != "undefined" &&
      document.implementation.hasFeature( "html", "1.0" ) || ie55 )
      
  // IE55 has a serious DOM1 bug... Patch it!
  if ( ie55 ) {
    document._getElementsByTagName = document.getElementsByTagName;
    document.getElementsByTagName = function ( sTagName ) {
      if ( sTagName == "*" )
        return document.all;
      else
        return document._getElementsByTagName( sTagName );
    };
  }

  return hasSupport.support;
}

///////////////////////////////////////////////////////////////////////////////////
// The constructor for tab panes
//
// el : HTMLElement    The html element used to represent the tab pane
// bUseCookie : Boolean  Optional. Default is true. Used to determine whether to us
//            persistance using cookies or not
//
function WebFXTabPane( el, bUseCookie ) {
  if ( !hasSupport() || el == null ) return;
  
  this.element = el;
  this.element.tabPane = this;
  this.pages = [];
  this.selectedIndex = null;
  this.useCookie = bUseCookie != null ? bUseCookie : false;
  
  // add class name tag to class name
  this.element.className = this.classNameTag + " " + this.element.className;
  
  // add tab row
  this.tabRow = document.createElement( "div" );
  this.tabRow.className = "tab-row";
  el.insertBefore( this.tabRow, el.firstChild );

  var tabIndex = 0;
  if ( this.useCookie ) {
    tabIndex = Number( WebFXTabPane.getCookie( "webfxtab_" + this.element.id ) );
    if ( isNaN( tabIndex ) )
      tabIndex = 0;
  }
  this.selectedIndex = tabIndex;
  
  // loop through child nodes and add them
  var cs = el.childNodes;
  var n;
  for (var i = 0; i < cs.length; i++) {
    if (cs[i].nodeType == 1 && cs[i].className == "tab-page") {
      this.addTabPage( cs[i] );
    }
  }
}

WebFXTabPane.prototype.classNameTag = "dynamic-tab-pane-control";

WebFXTabPane.prototype.setSelectedIndex = function ( n ) {
  if (this.selectedIndex != n) {
    if (this.selectedIndex != null && this.pages[ this.selectedIndex ] != null )
      this.pages[ this.selectedIndex ].hide();
    this.selectedIndex = n;
    this.pages[ this.selectedIndex ].show();
    
    if ( this.useCookie )
      WebFXTabPane.setCookie( "webfxtab_" + this.element.id, n );  // session cookie
  }
};
  
WebFXTabPane.prototype.getSelectedIndex = function () {
  return this.selectedIndex;
};
  
WebFXTabPane.prototype.addTabPage = function ( oElement ) {
  if ( !hasSupport() ) return;
  
  if ( oElement.tabPage == this )  // already added
    return oElement.tabPage;

  var n = this.pages.length;
  var tp = this.pages[n] = new WebFXTabPage( oElement, this, n );
  tp.tabPane = this;
  
  // move the tab out of the box
  this.tabRow.appendChild( tp.tab );
      
  if ( n == this.selectedIndex )
    tp.show();
  else
    tp.hide();
    
  return tp;
};
  
WebFXTabPane.prototype.dispose = function () {
  this.element.tabPane = null;
  this.element = null;    
  this.tabRow = null;
  
  for (var i = 0; i < this.pages.length; i++) {
    this.pages[i].dispose();
    this.pages[i] = null;
  }
  this.pages = null;
};



// Cookie handling
WebFXTabPane.setCookie = function ( sName, sValue, nDays ) {
  var expires = "";
  if ( nDays ) {
    var d = new Date();
    d.setTime( d.getTime() + nDays * 24 * 60 * 60 * 1000 );
    expires = "; expires=" + d.toGMTString();
  }

  document.cookie = sName + "=" + sValue + expires + "; path=/";
};

WebFXTabPane.getCookie = function (sName) {
  var re = new RegExp( "(\;|^)[^;]*(" + sName + ")\=([^;]*)(;|$)" );
  var res = re.exec( document.cookie );
  return res != null ? res[3] : null;
};

WebFXTabPane.removeCookie = function ( name ) {
  setCookie( name, "", -1 );

};

function WebFXTabPage( el, tabPane, nIndex ) {
  if ( !hasSupport() || el == null ) return;
  
  this.element = el;
  this.element.tabPage = this;
  this.index = nIndex;
  
  var cs = el.childNodes;
  for (var i = 0; i < cs.length; i++) {
    if (cs[i].nodeType == 1 && cs[i].className == "tab") {
      this.tab = cs[i];
      break;
    }
  }
  
  // insert a tag around content to support keyboard navigation
  
  
  var a = document.createElement( "A" );
  this.aElement = a;
  a.href = "#";
  a.onclick = function () { return false; };
  while ( this.tab.hasChildNodes() )
    a.appendChild( this.tab.firstChild );
  this.tab.appendChild( a );

  
  // hook up events, using DOM0
  var oThis = this;
  this.tab.onclick = function () { oThis.select(); };
  this.tab.onmouseover = function () { WebFXTabPage.tabOver( oThis ); };
  this.tab.onmouseout = function () { WebFXTabPage.tabOut( oThis ); };
}

WebFXTabPage.prototype.show = function () {
  var el = this.tab;
  var s = el.className + " selected";
  s = s.replace(/ +/g, " ");
  el.className = s;
  
  this.element.style.display = "block";
};

WebFXTabPage.prototype.hide = function () {
  var el = this.tab;
  var s = el.className;
  s = s.replace(/ selected/g, "");
  el.className = s;

  this.element.style.display = "none";
};
  
WebFXTabPage.prototype.select = function () {
  this.tabPane.setSelectedIndex( this.index );
};
  
WebFXTabPage.prototype.dispose = function () {
  this.aElement.onclick = null;
  this.aElement = null;
  this.element.tabPage = null;
  this.tab.onclick = null;
  this.tab.onmouseover = null;
  this.tab.onmouseout = null;
  this.tab = null;
  this.tabPane = null;
  this.element = null;
};

WebFXTabPage.tabOver = function ( tabpage ) {
  var el = tabpage.tab;
  var s = el.className + " hover";
  s = s.replace(/ +/g, " ");
  el.className = s;
};

WebFXTabPage.tabOut = function ( tabpage ) {
  var el = tabpage.tab;
  var s = el.className;
  s = s.replace(/ hover/g, "");
  el.className = s;
};


// This function initializes all uninitialized tab panes and tab pages
function setupAllTabs() {
  if ( !hasSupport() ) return;

  var all = document.getElementsByTagName( "*" );
  var l = all.length;
  var tabPaneRe = /tab\-pane/;
  var tabPageRe = /tab\-page/;
  var cn, el;
  var parentTabPane;
  
  for ( var i = 0; i < l; i++ ) {
    el = all[i]
    cn = el.className;

    // no className
    if ( cn == "" ) continue;
    
    // uninitiated tab pane
    if ( tabPaneRe.test( cn ) && !el.tabPane )
      new WebFXTabPane( el );
  
    // unitiated tab page wit a valid tab pane parent
    else if ( tabPageRe.test( cn ) && !el.tabPage &&
          tabPaneRe.test( el.parentNode.className ) ) {
      el.parentNode.tabPane.addTabPage( el );      
    }
  }
}

function disposeAllTabs() {
  if ( !hasSupport() ) return;
  
  var all = document.getElementsByTagName( "*" );
  var l = all.length;
  var tabPaneRe = /tab\-pane/;
  var cn, el;
  var tabPanes = [];
  
  for ( var i = 0; i < l; i++ ) {
    el = all[i]
    cn = el.className;

    // no className
    if ( cn == "" ) continue;
    
    // tab pane
    if ( tabPaneRe.test( cn ) && el.tabPane )
      tabPanes[tabPanes.length] = el.tabPane;
  }
  
  for (var i = tabPanes.length - 1; i >= 0; i--) {
    tabPanes[i].dispose();
    tabPanes[i] = null;
  }
}


// initialization hook up

// DOM2
if ( typeof window.addEventListener != "undefined" )
  window.addEventListener( "load", setupAllTabs, false );

// IE 
else if ( typeof window.attachEvent != "undefined" ) {
  window.attachEvent( "onload", setupAllTabs );
  window.attachEvent( "onunload", disposeAllTabs );
}

else {
  if ( window.onload != null ) {
    var oldOnload = window.onload;
    window.onload = function ( e ) {
      oldOnload( e );
      setupAllTabs();
    };
  }
  else 
    window.onload = setupAllTabs;
}