// $Id: zptabs-core.js 5271 2006-11-22 09:30:49Z jcastro $
/**
 * @fileoverview Tabs widget. Extends base Widget class (utils/zpwidget.js).
 *
 * <pre>
 * Copyright (c) 2006 by SouthProjects
 * http://www.southprojects.com
 * Santiago, Chile,
 * Version 1.2 Dec 2006.
 * All rights reserved.
 * </pre>
 */

/**
 * southprojects.Tab constructor. Creates a new tab object with given
 * parameters.
 *
 * @constructor
 * @extends southprojects.Widget
 * @param {object} objArgs Tab configuration
 *
 * Constructor recognizes the following properties of the config object
 * \code
 *	property name			| description
 *-------------------------------------------------------------------------------------------------
 *	id			| [string] Id of the tab. Used to identify the tab uniquely.
 *	linkInnerHTML   | [string] The HTML content to be placed inside link part
 *          | of the tab. That is the one inside the tab bar that you click on
 *          | to activate the tab.
 *	accessKey			| [string] Access key that activates the tab when pressed
 *	content	| [object, optional] Reference to HTMLElement object holding
 *          | content of the tab
 *	url	| [string, optional] URL of the content
 *	tabType	| [string] "div" or "iframe" depending on what kind of pane is
 *          | needed for the tab
 *	tab2tab	| [boolean] If true, pressing Tab key will open next tab. If false,
 *          | Tab key will also navigate through anchors and form fields inside
 *          | tab. Default: false.
 *	tabParent	| [object] Reference to HTMLElement that this tab is to be added to.
 *  changeUrl | [boolean] Specifies if browser location hash is to be changed
 *          | on every tab change to reflect the current tab
 * \endcode
 *
 */
southprojects.Tab = function(objArgs) {
  if(arguments.length == 0){
    objArgs = {};
  }

  // Call constructor of superclass
  southprojects.Tab.SUPERconstructor.call(this, objArgs);
};

/**
 * Unique static id of the widget class. Gives ability for southprojects#inherit to
 * determine and store path to this file correctly when it is included using
 * southprojects#include. When this file is included using southprojects#include or path
 * to this file is gotten using southprojects#getPath, this value must be specified
 * as script id.
 * @private
 */
southprojects.Tab.id = 'southprojects.Tab';

// Inherit Widget
southprojects.inherit(southprojects.Tab, southprojects.Widget);

/**
 * Initializes object.
 *
 * @param {object} objArgs User configuration
 */
southprojects.Tab.prototype.init = function(objArgs) {

  // processing Widget functionality
  southprojects.Tab.SUPERclass.init.call(this, objArgs);

  this.createTab();
};

/**
 * Creates elements needed for the new tab
 */
southprojects.Tab.prototype.createTab = function ()  {
  // Reference to tab link element
  southprojects.Utils.createProperty(this, 'linkNode', null);
  // Reference to pane containing tab content
  southprojects.Utils.createProperty(this, 'container', null);
  // Child element which gets focus first (needed for keyboard navigation)
  southprojects.Utils.createProperty(this, 'focusOn', null);
  southprojects.Utils.createProperty(this, 'linkHash', null);
  // If set an onTabChange event is to be called after onContentLoad
  southprojects.Utils.createProperty(this, 'pendingOnTabChange', null);

  // Create content with pane
	this.container = new southprojects.Pane({
		containerType : this.config.tabType,
    parent : this.config.tabParent
  });
	this.container.removeBorder();

  var self = this;
  // Define pane content loaded handler
  var onContentLoaded = function() {
    if (self.pendingOnTabChange) {
      self.pendingOnTabChange(self);
      self.pendingOnTabChange = null;
    }

    self.fireEvent('tabOnLoad');
  }

  // Add pane contentLoaded listener
  this.container.addEventListener('contentLoaded', onContentLoaded);

  // Hide content
  this.container.getContainer().style.display = 'none';
  this.container.getContainer().style.width = '100%';
  this.container.getContainer().style.height = '100%';

  if (!this.config.url) {
    // Update tab content
    this.setPaneContent();
  }

  // Get id
  if (this.config.id) {
    this.id = this.config.id;
  } else {
    this.id = this.container.getContainer().getAttribute('id');
    if (typeof this.id == 'string') {
      this.container.getContainer().removeAttribute('id');
    }
  }
  if (typeof this.id != 'string' || !this.id.length) {
    // Generate unique id
    this.id = southprojects.Utils.generateID('tab');
  }
  // Create link node
  this.linkNode = southprojects.Utils.createElement('a');
  this.linkNode.name = this.id;
  // Need "<span><span>" for themes
  this.linkNode.innerHTML = '<span><span>' + this.config.linkInnerHTML +
   '</span></span>';
  if (this.config.accessKey) {
    this.linkNode.accessKey = this.config.accessKey;
  }
  if (this.config.title) {
    this.linkNode.setAttribute('title', this.config.title);
  }
  var self = this;
  // Mouse navigation support
  this.linkNode.onclick = function() {
    self.fireEvent('activateTab');

    if (this.blur) {
      this.blur();
    }
    if (self.config.changeUrl) {
      // Modify window URL
      window.location.hash = self.linkHash;
    }
    // Don't navigate to link (don't refresh the page)
    return false;
  };
  // Keyboard navigation support
  this.linkNode.tabIndex = southprojects.Tab.tabIndex;
  if (!this.tab2tab) {
    // Next tabIndex is reserved for tab content
    southprojects.Tab.tabIndex += 2;
  // } else {
    // No need to increase tabIndex
  }
  // Activate tab on focus
  this.linkNode.onfocus = function() {
    self.fireEvent('activateTab');
    // Continue event
    return true;
  };
  // Setup keys
  this.linkNode.onkeydown = function(ev) {
    ev || (ev = window.event);
    switch (ev.keyCode) {
      case 13: // Enter
      case 32: // Space
        if (self.focusOn && self.focusOn.focus) {
          self.focusOn.focus();
        }
        // Stop event
        return false;
    }
    // Continue event
    return true;
  }
  // Determine child element which gets focus first
  if (this.container.getContainer().hasChildNodes()) {
    this.getFocusOn();
  }
}

/**
 * Sets tab link href given the hash
 *
 * @private
 * @param {string} linkHash Bookmark hash to set to link href
 */
southprojects.Tab.prototype.setLinkHash = function(linkHash)  {
  this.linkHash = linkHash;

  this.linkNode.setAttribute('href', '#' + linkHash);
}

/**
 * Configures the widget. Gets called from init and reconfigure methods of
 * superclass.
 *
 * @private
 * @param {object} objArgs User configuration
 */
southprojects.Tab.prototype.configure = function(objArgs) {
  // Define config options

  // Id of the tab
  this.defineConfigOption('id', null);
  // Tab link inner html
  this.defineConfigOption('linkInnerHTML', '');
  // Tab access key
  this.defineConfigOption('accessKey', '');
  // Tab content
  this.defineConfigOption('content', null);
  // URL of the content
  this.defineConfigOption('url', '');
  //should we show content in IFRAME Pane or just simple div Pane
  this.defineConfigOption('tabType', "div");

  // Keyboard navigation type
  this.defineConfigOption('tab2tab', false);
  // Tab parent
  this.defineConfigOption('tabParent', null);
  this.defineConfigOption('title', null);

  // If browser url needs to be changed on every tab change
  this.defineConfigOption('changeUrl', true);

  // Call parent method
  southprojects.Tab.SUPERclass.configure.call(this, objArgs);

  // Check if required param "tabParent" is defined
  if(typeof(this.config.tabParent) == "undefined"){
    southprojects.Log({description: "No reference to tab parent!"})
    return false;
  }

  // Check keyboard navigation type
  if (this.config.tab2tab && false != this.config.tab2tab) {
    this.config.tab2tab = true;
  }

  // Check tabType
  if (typeof this.config.tabType == "string") {
    this.config.tabType = this.config.tabType.toLowerCase();
  }
  if(this.config.tabType != "div" && objArgs.tabType != "iframe")
  {
    this.config.tabType = "div";
  }

};

/**
 * Counter that gets increased after Tab is added. Required for keyboard
 * navigation support.
 *
 * Note:
 * In Opera tabIndex property value must be > 0, otherwise node is ignored.
 * Mozilla starts travelling from nodes with tabIndex > 0.
 * IE starts travelling from nodes with tabIndex == 0.
 * All nodes without tabIndex set explicitly have tabIndex == 0.
 */
southprojects.Tab.tabIndex = 1000;

/**
 * Determines child node of the container which gets focus first.
 * Needed for keyboard navigation.
 * @private
 */
southprojects.Tab.prototype.getFocusOn = function() {
  // Remove old value
  this.focusOn = null;
  // Check keyboard navigation type
  if (this.tab2tab) {
    return;
  }
  // Put it in separate process to speed up initialization
  var self = this;
  setTimeout(function() {
    // Flag to determine lower tabIndex
    var iTabIndex = 0;
    // Gets element with lower tabIndex
    function parse(objNode) {
      var objChild = objNode.firstChild;
      while (objChild) {
        if (objChild.nodeType == 1) { // ELEMENT_NODE
          var strTag = objChild.tagName.toLowerCase();
          if (strTag == 'a' || strTag == 'input' || strTag == 'select' ||
           strTag == 'textarea' || strTag == 'button') {
            // Element may obtain focus
            if (!self.focusOn) {
              self.focusOn = objChild;
            } else if (objChild.tabIndex && objChild.tabIndex > 0 &&
             (!iTabIndex || iTabIndex > objChild.tabIndex)) {
              self.focusOn = objChild;
              iTabIndex = objChild.tabIndex;
            }
            if (!objChild.tabIndex) {
              objChild.tabIndex = self.linkNode.tabIndex + 1;
            }
          }
          parse(objChild);
        }
        objChild = objChild.nextSibling;
      }
    };
    // Parse tab contenet
    parse(self.container);
  }, 0);
};

/**
 * Sets tab content from given HTML fragment.
 *
 * @param {string} strHtml HTML fragment.
 * @private
 */
southprojects.Tab.prototype.setInnerHtml = function(strHtml) {
  // Set tab content
  southprojects.Transport.setInnerHtml({
    html: strHtml,
    container: this.container.getContainer()
  });
  // Determine child element which gets focus first
  this.getFocusOn();
}

/**
 * Sets tab pane content
 *
 * @public
 * @param {mixed} content value for the content
 * @param {string} type type of content: "html", "html/text", "html/url"
 * @return {boolean} true if successfull, otherwise false.
 */
southprojects.Tab.prototype.setPaneContent = function(content, type)  {
  var self = this;

  if(!this.container.isReady()){
    setTimeout(function(){self.setPaneContent(content, type)}, 50);
    return null;
  }


  if (typeof content != "undefined") {
    this.container.setPaneContent(content, type);
  }
  else if (this.config.url && 0 < this.config.url.length) {
	  this.container.setPaneContent(this.config.url, 'html/url');
	} else {
	  this.container.setPaneContent(this.config.content);
	}
}




/**
 * southprojects.Tabs constructor. Creates a new tabs object with given
 * parameters.
 *
 * @constructor
 * @extends southprojects.Widget
 * @param {object} objArgs Tab configuration
 *
 * Constructor recognizes the following properties of the config object
 * \code
 *	property name			| description
 *-------------------------------------------------------------------------------------------------
 *	tabBar		| [object or string] Element or id of element that will hold
 *            | the tab bar.
 *	tabs			| [object or string] Element or id of element that will hold the
 *            | tabs. This option is also used as "source" if the last is not
 *            | specified.
 *	onInit		| [function] Called when tabs are created. Users can perform
 *            | problem-specific initializations at this stage. No arguments.
 *	onTabChange		| [function] Called after the tab was changed. Receives
 *            |  following object:
 *            |  {
 *            |  oldTabId: [string] id of the old tab,
 *            |  newTabId: [string] id of the new tab
 *            |  }
 *	onBeforeTabChange		| [function] Called when the tab is about to be changed,
 *            | just before. Receives following object:
 *            | {
 *            |  oldTabId: [string] id of the old tab,
 *            |  newTabId: [string] id of the new tab
 *            | }
 *            | Should return boolean. If returns other than "true", tab will
 *            | not be changed.
 *	ignoreUrl		| [boolean] If true, "#tabId" part of URL is ignored and first
 *            | tab is opened after initialization.
 *  changeUrl | [boolean] Specifies if browser location hash is to be changed
 *          | on every tab change to reflect the current tab
 *	tab2tab		| [boolean] If true, pressing Tab key will open next tab.
 *            | If false, Tab key will also navigate through anchors and form
 *            | fields inside tab. Default: false.
 *	scrollMultiple | [boolean] If true, scrolls the tabs one 'page' at a time.
 *            | Otherwise, scrolls singly.
 *	iframeContent | [boolean] Marks the pane content as being an <iframe>
 *	refreshIframes | [boolean] Flag whether iframes should refreshed on tab change
 *	windowOnLoad | [function] If set, this is run on window load.
 */
southprojects.Tabs = function(objArgs) {
  if(arguments.length == 0){
    objArgs = {};
  }

  southprojects.Tabs.SUPERconstructor.call(this, objArgs);
};

/**
 * Unique static id of the widget class. Gives ability for southprojects#inherit to
 * determine and store path to this file correctly when it is included using
 * southprojects#include. When this file is included using southprojects#include or path
 * to this file is gotten using southprojects#getPath, this value must be specified
 * as script id.
 * @private
 */
southprojects.Tabs.id = 'southprojects.Tabs';

// Inherit Widget
southprojects.inherit(southprojects.Tabs, southprojects.Widget);

/**
 * Initializes object.
 *
 * @param {object} objArgs User configuration
 */
southprojects.Tabs.prototype.init = function(objArgs) {

  // Call init method of superclass
  southprojects.Tabs.SUPERclass.init.call(this, objArgs);

  this.createTabs();

  this.initTabBar();
};

/**
* Creates tabs DOM elements
* @private
*/
southprojects.Tabs.prototype.createTabs = function() {
  // To maintain by id
  southprojects.Utils.createProperty(this, 'tabs', {});
  // To maintain by index
  southprojects.Utils.createProperty(this, 'tabsArray', []);

  if (null == this.tabsThemeSuffix) {
    this.tabsThemeSuffix = 'Content';
  }

  // Apply theme
  southprojects.Utils.addClass(this.config.tabs, this.getClassName({
    prefix: 'zpTabs',
    suffix: this.tabsThemeSuffix
  }));

  // Call parent method to load data from the specified source
  this.loadData();

  // Index of the current tab
  this.currentIndex = -1;
  // onInit
  if (typeof this.config.onInit == 'function') {
    this.config.onInit();
  }

  // Go to first tab
  if (this.tabsArray.length) {
    var strId = this.tabsArray[0].id;
    if (!this.config.ignoreUrl) {
      if (/#tabInfo=([^\/]+)$/.test(document.URL) && this.tabs[RegExp.$1]) {
        strId = RegExp.$1;
      }
    }
    this.changeTab(strId);
  }

  // If windowOnLoad is set, run it
  if(this.config.windowOnLoad!=null)
  {
	  this.config.windowOnLoad();
  }

  // If tab bar is not disabled
  if (true != this.noTabBar) {
    // Make tabs visible
    this.addEventListener('loadThemeEnd', function() {
      this.config.tabBar.style.display = 'block';
    });
  }
}

/**
 * Configures the widget. Gets called from init and reconfigure methods of
 * superclass.
 *
 * @private
 * @param {object} objArgs User configuration
 */
southprojects.Tabs.prototype.configure = function(objArgs) {
  // Define config options
  this.defineConfigOption('tabBar', null);
  this.defineConfigOption('tabs', null);
  this.defineConfigOption('onInit', null);
  this.defineConfigOption('onTabChange', null);
  this.defineConfigOption('onBeforeTabChange', null);

  // If location hash is to be parsed on page initialization
  this.defineConfigOption('ignoreUrl', false);
  // If browser url needs to be changed on every tab change
  this.defineConfigOption('changeUrl', true);

  this.defineConfigOption('tab2tab', false);
  this.defineConfigOption('scrollMultiple', null);

  //should we show content in IFRAME Pane or just simple div Pane
  this.defineConfigOption('iframeContent', null);
  this.defineConfigOption('tabType', false);

  this.defineConfigOption('refreshIframes', false);
  this.defineConfigOption('windowOnLoad', null);

  this.defineConfigOption('scrolls', false);
  this.defineConfigOption('noMoreTabsLeft', false);
  this.defineConfigOption('lastIndexLeft', 0);
  this.defineConfigOption('noMoreTabsRight', true);
  this.defineConfigOption('lastIndexRight', null);

  // Determine scroll type
  if(this.config.scroll==null)
  {
	  this.config.scrollMultiple = false;
  }
  else if(this.config.scrollMultiple!=true && this.config.scrollMultiple!=false)
  {
	  this.config.scrollMultiple = false;
  }

  // Call parent method
  southprojects.Tabs.SUPERclass.configure.call(this, objArgs);

  // If tab bar is not disabled
  if (true != this.noTabBar) {
    this.config.tabBar = southprojects.Widget.getElementById(this.config.tabBar);
    if (!this.config.tabBar) {
      southprojects.Log({description: "Can't find container for tab bar (\"tabBar\" config option)"});
      return;
    }
  }

  if ("string" == typeof this.config.tabs) {
    this.config.tabs = southprojects.Widget.getElementById(this.config.tabs);
  }

  if (!this.config.tabs) {
    southprojects.Log({description: "Can't find container for tab contents (\"tabs\" config option)"});
    return;
  }

  // Check tabType
  if (typeof this.config.tabType == "string") {
    this.config.tabType = this.config.tabType.toLowerCase();
  }
  if(this.config.tabType != "div" && objArgs.tabType != "iframe")
  {
    this.config.tabType = "div";
  }

  if (true == this.config.iframeContent) {
    this.config.tabType = "iframe";
  }
};

/**
 * Initializes the tab bar based on tabBar config property.
 */
southprojects.Tabs.prototype.initTabBar = function() {
  // If tab bar is disabled
  if (true == this.noTabBar) {
    return;
  }

  // Apply theme
  southprojects.Utils.addClass(this.config.tabBar, this.getClassName({
    prefix: 'zpTabs'
  }));

  // Determine width of content of tab bar
  var _tabBarContentWidth = 0;
  var items = this.config.tabBar.childNodes;
  var tmp = '';

  for(var i=0; i<items.length; i++){
      if(items[i].nodeType != 1){
        continue;
      }

	  // Must "cast" this to an absolutely positioned element for IE to get the correct width
	  tmp = items[i].style.position;
	  items[i].style.position = 'absolute';

	  // Store real width in element for future use
	  // Opera reports the widths of elements outside the content tab to have width of -1.
	  // For this reason, hide elements you've recorded to allow other elements to come into viewport
	  // Get the display type for all tabs, default to 'inline'
	  items[i].originalDisplayType = items[i].style.display != '' ? items[i].style.display : 'inline';
	  _tabBarContentWidth += items[i].offsetWidth;
	  items[i].realWidth = items[i].offsetWidth;
	  items[i].style.display = 'none';

	  // "Cast" back to original positioning
	  items[i].style.position = tmp;

	  // Capture tabs index in the tab bar
	  items[i].arrayPosition = i;
  }

  // Restore display to all tabs
  for(var i=0; i<items.length; i++)
  {
      if(items[i].nodeType != 1){
        continue;
      }

	  items[i].style.display = items[i].originalDisplayType;
  }

  // If the content width of the tab bar exceeds the current width of the tab bar...
  var _tabBarWidth = this.config.tabBar.offsetWidth;
  if(_tabBarContentWidth>_tabBarWidth)
  {
	  this.config.scrolls = true;

	  // Find the first child node within the tab bar, which extends beyond tab bar's border
	  var tmp = 0;
	  var i = 0; while(tmp<_tabBarWidth) tmp += items[i++].realWidth;

	  // Scroll page at a time
	  //if(this.config.scrollMultiple)
	  //{
		  	  i--;
	  //}

	  // Hide all elements of tab bar, which extend beyond tab bar's border
	  for(i; i<items.length; i++)
	  {
		  items[i].style.display = 'none';
	  }

	  // Display scrollies for tabs
	  var _leftScrolly = southprojects.Utils.createElement('span');
	  _leftScrolly.innerHTML = '&lt;';
	  var _rightScrolly = southprojects.Utils.createElement('span');
	  _rightScrolly.innerHTML = '&gt;';

	  // Attach scrolling functions
	  var self = this;
	  _rightScrolly.onclick = (this.config.scrollMultiple) ? function () {self.scrollTabsLeft(true)} : function () {self.scrollOneTabLeft(true)};
	  _leftScrolly.onclick = (this.config.scrollMultiple) ? function () {self.scrollTabsRight(true)} : function () {self.scrollOneTabRight(true)};

	  // Make mouseover effects for the scrolly buttons
	  var mouseoverFunc = function ()
	  {
		  this.style.color = 'black';
	  }
	  _leftScrolly.onmouseover = mouseoverFunc;
	  _rightScrolly.onmouseover = mouseoverFunc;

	  var mouseoutFunc = function ()
	  {
		  this.style.color = '#aaa';
	  }
	  _leftScrolly.onmouseout = mouseoutFunc;
	  _rightScrolly.onmouseout = mouseoutFunc;

	  var _scrollyContainer = southprojects.Utils.createElement('div');
	  _scrollyContainer.className = 'zpTabsScrolly';
	  _scrollyContainer.appendChild(_leftScrolly);
	  _scrollyContainer.appendChild(_rightScrolly);

	  if(this.config.scrollMultiple)
	  {
		  this.config.tabBar.parentNode.insertBefore(_scrollyContainer,
              this.config.tabBar.nextSibling);
	  }
  }

}

/**
 * Adds a tab link to the tab bar
 *
 * @param {object} objTab object tab.
 */
southprojects.Tabs.prototype.addToTabBar = function(objTab) {
  if (true != this.noTabBar) {
    // Put this tab on tab bar
    this.config.tabBar.appendChild(objTab.linkNode);
  }
}

/**
 * Attaches a tab to the tabs
 *
 * @param {object} objTab object tab.
 */
southprojects.Tabs.prototype.appendTab = function(objTab) {

  objTab.index = this.tabsArray.length;
  // Attach this Tab to Tabs object
  this.tabsArray[objTab.index] = objTab;
  this.tabs[objTab.id] = objTab;

  // Set tab link hash
  var linkHash = this.config.tabs.id + "=" + objTab.id;
  objTab.setLinkHash(linkHash);

  var self = this;
  objTab.addEventListener("activateTab", function() {
    self.changeTab(objTab.id);
  } );
}

/**
 * Scrolls tabs to the left
 *
 * @private
 * @param {boolean} setTab Whether the function should set the selected tab
 * on its own.
 */
southprojects.Tabs.prototype.scrollOneTabLeft = function(setTab) {
	var tabBar = this.config.tabBar;

	// Get tabs
	var items = tabBar.childNodes;

	// Find first visible tab
	var i = 0;
	for(i; i<items.length; i++)
	{
		if(items[i].style.display!='none')
		{
			break;
		}
	}

	// Find first hidden tab
	var j = i;
	for(j; j<items.length; j++)
	{
		if(items[j].style.display=='none')
		{
			break;
		}
	}

	if(j>=items.length)
	{
		return;
	}

	// Hide first visible tab, show first hidden tab
	items[i].style.display = 'none';

	// If there aren't any hidden tabs left, don't try to display any
	if(j<items.length)
	{
		items[j].style.display = items[j].originalDisplayType;
	}
}

/**
 * Scrolls tabs to the left
 *
 * @private
 * @param {boolean} setTab Whether the function should set the selected tab
 * on its own.
 */
southprojects.Tabs.prototype.scrollOneTabRight = function(setTab) {
	var tabBar = this.config.tabBar;

	// Get tabs
	var items = tabBar.childNodes;

	// Find first visible tab
	var i = 0;
	for(i; i<items.length; i++)
	{
		if(items[i].style.display!='none')
		{
			break;
		}
	}

	// If i==0, you're at the beginning of the tabs, just exit
	if(i==0)
	{
		return;
	}

	// Find first hidden tab
	var j = i;
	for(j; j<items.length; j++)
	{
		if(items[j].style.display=='none')
		{
			break;
		}
	}

	// Hide last visible tab, show first hidden tab previous to the first visible tab
	items[j-1].style.display = 'none';
	items[i-1].style.display = items[i-1].originalDisplayType;
}

/**
 * Scrolls tabs to the left
 *
 * @private
 * @param {boolean} setTab Whether the function should set the selected tab
 * on its own.
 */
southprojects.Tabs.prototype.scrollTabsLeft = function(setTab) {
	// Quit if you're at the end
	if(this.config.noMoreTabsLeft)
	{
		return;
	}

	// Mark that there are now (or will be) hidden tabs on the left
	this.config.noMoreTabsRight = false;

	// Check arguments
	if(!this.config.tabBar)
	{
		return;
	}
	var tabBar = this.config.tabBar;

	// Content width of the tab bar
	var contentWidth = parseInt(tabBar.style.width);

	// Run through tabs hiding those that are currently visible
	var items = tabBar.childNodes;
	var i = this.config.lastIndexLeft - 1;
	while(++i<items.length)
	{
		if(items[i].style.display!='none')
		{
			items[i].style.display = 'none';
		}
		else
		{
			this.config.lastIndexLeft = i;
			break;
		}
	}

	// Now, make elements visible until you run out of room, or until there aren't any left
	var contentWidth = 0;
	var tabBarWidth = parseInt(tabBar.style.width);
	for(i=this.config.lastIndexLeft; i<items.length; i++)
	{
		items[i].style.display = items[i].originalDisplayType;
		contentWidth += items[i].realWidth;

		// If you've exceeded viewable area, retract
		if(contentWidth>tabBarWidth)
		{
			items[i].style.display = 'none';
			this.config.lastIndexRight = i - 1;

			// Make first visible tab the current tab
			if(setTab)
			{
				this.changeTab(items[this.config.lastIndexLeft].name);
			}

			return;
		}
	}

	// Adjust lastIndexRight for last increment performed in for loop
	this.config.lastIndexRight = i - 1;

	// Make first visible tab the current tab
	if(setTab)
	{
		this.changeTab(items[this.config.lastIndexLeft].name);
	}

	this.config.noMoreTabsLeft = true;
}

/**
 * Scrolls tabs to the right
 *
 * @private
 * @param {boolean} setTab Whether the function should set the selected tab
 * on its own.
 */
southprojects.Tabs.prototype.scrollTabsRight = function(setTab) {
	// Quit if you're at the end
	if(this.config.noMoreTabsRight)
	{
		return;
	}

	// Mark that there are now (or will be) hidden tabs on the right
	this.config.noMoreTabsLeft = false;

	// Check arguments
	if(!this.config.tabBar)
	{
		return;
	}
	var tabBar = this.config.tabBar;

	// Content width of the tab bar
	var contentWidth = parseInt(tabBar.style.width);

	// Run through tabs hiding those that are currently visible
	// Need some sort of pagination here
	var items = tabBar.childNodes;
	var i = this.config.lastIndexRight + 1;
	while(--i>=0)
	{
		if(items[i].style.display!='none')
		{
			items[i].style.display = 'none';
		}
		else
		{
			this.config.lastIndexRight = i;
			break;
		}
	}

	// Now, make elements visible until you run out of room, or until there aren't any left
	var contentWidth = 0;
	var tabBarWidth = parseInt(tabBar.style.width);
	for(i=this.config.lastIndexRight; i>=0; i--)
	{
		items[i].style.display = items[i].originalDisplayType;
		contentWidth += items[i].realWidth;

		// If you've exceeded viewable area, retract
		if(contentWidth>tabBarWidth)
		{
			items[i].style.display = 'none';
			this.config.lastIndexLeft = i + 1;

			// Make first visible tab the current tab
			if(setTab)
			{
				this.changeTab(items[this.config.lastIndexRight].name);
			}

			return;
		}
	}

	// Adjust lastIndexLeft for last decrement performed in for loop
	this.config.lastIndexLeft = i + 1;

	// Make first visible tab the current tab
	if(setTab)
	{
		this.changeTab(items[this.config.lastIndexRight].name);
	}

	this.config.noMoreTabsRight = true;
}

/**
 * Loads data from the JSON source.
 *
 * @private
 * Following format is recognized:
 * \code
 * {
 *   tabs: [
 *     {
 *       id: [string, optional] id of the tab,
 *       innerHTML: [string] label,
 *       accessKey: [string, optional] access key,
 *       title: [string] title,
 *       url: [string] URL of the content,
 *		 tabType: [string] "div" or "iframe" for the content pane
 *     },
 *     ...
 *   ]
 * }
 * \endcode
 *
 * @param {object} objSource JSON object.
 */
southprojects.Tabs.prototype.loadDataJson = function(objSource) {
  // Check arguments
  if ((true != this.noTabBar && !this.config.tabBar) || !this.config.tabs) {
    return;
  }
  if (!objSource || !objSource.tabs || !objSource.tabs.length) {
    return;
  }
  // Parse source
  var iLen = objSource.tabs.length;
  for (var iTab = 0; iTab < iLen; iTab++) {
    var objTabDef = objSource.tabs[iTab];
    // If no tabType is set to this tab
    if (!objTabDef.tabType) {
      // Use config option from Tabs
      objTabDef.tabType = this.config.tabType;
    }
    objTabDef.tabParent = this.config.tabs;
    objTabDef.changeUrl = this.config.changeUrl;
    // Create tab
    var objTab = this.newTab(objTabDef);

    // Return id of the tab trough objSource
    if (objTab.id) {
      objTabDef.id = objTab.id;
    }

    this.addToTabBar(objTab);

    this.appendTab(objTab);

  }
};

/**
 * Create a new tab instance
 *
 * @param {object} objArgs tab configuration
 */
southprojects.Tabs.prototype.newTab = function(objArgs) {
  var objTab = new southprojects.Tab(objArgs);
  return objTab;
}

/**
 * Loads data from the HTML source.
 *
 * @private
 * Following format is recognized:
 * \code
 * <div id="tabs">
 *   <div id="tab-begin">
 *     <label>The first tab</label>
 *     ... the tab contents here ...
 *   </div>
 *   <div id="tab-second">
 *     <label>The second tab</label>
 *     ... the tab contents here ...
 *   </div>
 *   ...
 * </div>
 * \endcode
 *
 * @param {object} objSource HTMLElement object.
 */
southprojects.Tabs.prototype.loadDataHtml = function(objSource) {
  // Check arguments
  if ((true != this.noTabBar && !this.config.tabBar) || !this.config.tabs) {
    return;
  }
  if (!objSource) {
    objSource = this.config.tabs;
  }

  var childs = [];
  for(var ii = 0; ii < objSource.childNodes.length; ii++){
    childs.push(objSource.childNodes[ii]);
  }

  // Parse source
  for (var iChild = 0; iChild < childs.length; iChild++) {
    var objChild = childs[iChild];

    if (objChild.nodeType == 1) { // ELEMENT_NODE
      // Get label
      var objLabel = southprojects.Utils.getFirstChild(objChild, 'label');
      if (!objLabel) {
        continue;
      }

      // Remove label
      objLabel.parentNode.removeChild(objLabel);
      // Remove child
      objChild.parentNode.removeChild(objChild);

      var objArgs = {
        tabParent: this.config.tabs,
        linkInnerHTML: objLabel.innerHTML,
        accessKey: objLabel.getAttribute('accesskey'),
        title: objLabel.getAttribute('title'),
        content: objChild,
        tabType: objChild.getAttribute('name')
      };

      objArgs.changeUrl = this.config.changeUrl;
      // Create tab
      var objTab = this.newTab(objArgs);

      this.addToTabBar(objTab);

      this.appendTab(objTab);

      // Return id of the tab trough container element
      if (objTab.id) {
        objTab.container.getContainer().setAttribute('id', objTab.id);
      }
    }
  }
};

/**
 * Display a new tab. If onBeforeTabChange() returns false, the operation is
 * cancelled.
 *
 * @param {string} strNewTabId id of the new tab.
 */
southprojects.Tabs.prototype.changeTab = function(strNewTabId) {
  var strCurrTabId = null;
  var objTab = null;
  if (this.tabsArray[this.currentIndex]) {
    strCurrTabId = this.tabsArray[this.currentIndex].id;
    objTab = this.tabsArray[this.currentIndex];
  }
  if (strCurrTabId != strNewTabId) {
    // Check if callback function allows to change tab
    var boolChangeTab = true;
    if (typeof this.config.onBeforeTabChange == 'function') {
      boolChangeTab = this.config.onBeforeTabChange({
        oldTabId: strCurrTabId,
        newTabId: strNewTabId
      });
    }
    if (!boolChangeTab) {
      // Return focus back
      if (objTab && objTab.linkNode.focus) {
        // Need to focus on tab first because FF 1.5 seems to have separate
        // focus for links
        objTab.linkNode.focus();
        // Focus on content (in separate thread to let it focus on tab first)
        setTimeout(function() {
          if (objTab.focusOn && objTab.focusOn.focus) {
            objTab.focusOn.focus();
          }
        }, 0);
      }
      return;
    }

    if(this.config.scrolls)
    {
		// If you're moving out of the visible tabs, scroll accordingly
		var _newTab = this.tabsArray[this.tabs[strNewTabId].index].linkNode;
		if(this.tabsArray[this.currentIndex])
		{
			var _curTab = this.tabsArray[this.currentIndex].linkNode;
		}
		else
		{
			var _curTab = this.tabsArray[0].linkNode;
		}
		if(_curTab.arrayPosition<_newTab.arrayPosition)
		{
			if(this.config.scrollMultiple)
			{
				while(_newTab.style.display=='none')
				{
					this.scrollTabsLeft(false);
				}
			}
			else
			{
				while(_newTab.style.display=='none')
				{
					this.scrollOneTabLeft(false);
				}
			}
		}
		else if(_curTab.arrayPosition>_newTab.arrayPosition)
		{
			if(this.config.scrollMultiple)
			{
				while(_newTab.style.display=='none')
				{
					this.scrollTabsRight(false);
				}
			}
			else
			{
				while(_newTab.style.display=='none')
				{
					this.scrollOneTabRight(false);
				}
			}
		}
	}

    // Change tab
    if (objTab) {
      // Hide old tab
      objTab.container.getContainer().style.display = 'none';
      southprojects.Utils.removeClass(objTab.linkNode, 'zpTabsActive');
    }
    objTab = this.tabs[strNewTabId];
    // Show new tab
    objTab.container.getContainer().style.display = 'block';

    // Refresh iframe element?
    if(this.config.refreshIframes)
    {
		var iframes = objTab.container.getContainer().getElementsByTagName('iframe');

		for(var i=0; i<iframes.length; i++)
		{
			window.parent.frames[iframes[i].name].location.reload(true)
		}
	}

    southprojects.Utils.addClass(objTab.linkNode, 'zpTabsActive');
    this.currentIndex = objTab.index;
    // If tab is still empty and
    // tab is configured to load content from external source
    if (!objTab.container.getContainer().childNodes.length && objTab.config.url) {
      // If onTabChange handler is specified
      if (typeof this.config.onTabChange == 'function') {
        var self = this;
        objTab.pendingOnTabChange = function() {
          // Call onTabChange event handler
          self.config.onTabChange({
            oldTabId: strCurrTabId,
            newTabId: strNewTabId
          });
        }
      }

      // Load remote url inside tab
      objTab.setPaneContent(this.config.url, 'html/url');
    }
    else {
      if (!objTab.config.url) {
        // Update tab content
        objTab.setPaneContent();
      }

      if (typeof this.config.onTabChange == 'function') {
        // Call onTabChange event handler
        this.config.onTabChange({
          oldTabId: strCurrTabId,
          newTabId: strNewTabId
        });
      }
    }
  }
};

/**
 * Gets a tab with a given id
 *
 * @param {string} tabId id of the tab to get
 */
southprojects.Tabs.prototype.getTab = function(tabId) {
  var objTab = this.tabs[tabId];
  return objTab;
};

/**
 * Moves to the next tab.
 */
southprojects.Tabs.prototype.nextTab = function() {

  if (this.currentIndex < this.tabsArray.length - 1) {

	this.changeTab(this.tabsArray[this.currentIndex + 1].id);

  } else {
    this.firstTab();
  }
};

/**
 * Moves to the previous tab.
 */
southprojects.Tabs.prototype.prevTab = function() {
  if (this.currentIndex > 0) {

    this.changeTab(this.tabsArray[this.currentIndex - 1].id);

  } else {
    this.lastTab();
  }
};

/**
 * Moves to the first tab.
 */
southprojects.Tabs.prototype.firstTab = function() {
  this.changeTab(this.tabsArray[0].id);
};

/**
 * Moves to the last tab.
 */
southprojects.Tabs.prototype.lastTab = function() {
  this.changeTab(this.tabsArray[this.tabsArray.length - 1].id);
};

/**
 * Indicates if current tab is first.
 *
 * @return {boolean} true if we are at the first tab, false otherwise.
 */
southprojects.Tabs.prototype.isFirstTab = function() {
  return this.currentIndex == 0;
};

/**
 * Indicates if current tab is last.
 *
 * @return {boolean} true if we are at the last tab, false otherwise.
 */
southprojects.Tabs.prototype.isLastTab = function() {
  return this.currentIndex == this.tabsArray.length - 1;
};
