/*----------------------------------------------------------------------------\
|                               Help Tip 1.12                                 |
|-----------------------------------------------------------------------------|
|                         Created by Erik Arvidsson                           |
|                  (http://webfx.eae.net/contact.html#erik)                   |
|                      For WebFX (http://webfx.eae.net/)                      |
|-----------------------------------------------------------------------------|
|           A tool tip like script that can be used for context help          |
|-----------------------------------------------------------------------------|
|                  Copyright (c) 1999 - 2002 Erik Arvidsson                   |
|-----------------------------------------------------------------------------|
| This software is provided "as is", without warranty of any kind, express or |
| implied, including  but not limited  to the warranties of  merchantability, |
| fitness for a particular purpose and noninfringement. In no event shall the |
| authors or  copyright  holders be  liable for any claim,  damages or  other |
| liability, whether  in an  action of  contract, tort  or otherwise, arising |
| from,  out of  or in  connection with  the software or  the  use  or  other |
| dealings in the software.                                                   |
| - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
| This  software is  available under the  three different licenses  mentioned |
| below.  To use this software you must chose, and qualify, for one of those. |
| - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
| The WebFX Non-Commercial License          http://webfx.eae.net/license.html |
| Permits  anyone the right to use the  software in a  non-commercial context |
| free of charge.                                                             |
| - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
| The WebFX Commercial license           http://webfx.eae.net/commercial.html |
| Permits the  license holder the right to use  the software in a  commercial |
| context. Such license must be specifically obtained, however it's valid for |
| any number of  implementations of the licensed software.                    |
| - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
| GPL - The GNU General Public License    http://www.gnu.org/licenses/gpl.txt |
| Permits anyone the right to use and modify the software without limitations |
| as long as proper  credits are given  and the original  and modified source |
| code are included. Requires  that the final product, software derivate from |
| the original  source or any  software  utilizing a GPL  component, such  as |
| this, is also licensed under the GPL license.                               |
|-----------------------------------------------------------------------------|
| 2002-09-27 |                                                                |
| 2001-11-25 | Added a resize to the tooltip if the document width is too     |
|            | small.                                                         |
| 2002-05-19 | IE50 did not recognise the JS keyword undefined so the test    |
|            | for scroll support was updated to be IE50 friendly.            |
| 2002-07-06 | Added flag to hide selects for IE                              |
| 2002-10-04 | (1.1) Restructured and made code more IE garbage collector     |
|            | friendly. This solved the most nasty memory leaks. Also added  |
|            | support for hiding the tooltip if ESC is pressed.              |
| 2002-10-18 | Fixed verrical position in case of scrolled document.          |
| 2002-12-02 | Mozilla bug workaround related to mousedown and move.          |
|-----------------------------------------------------------------------------|
| Dependencies: helptip.css (To set up the CSS of the help-tooltip class)     |
|-----------------------------------------------------------------------------|
| Usage:                                                                      |
|                                                                             |
|   <script type="text/javascript" src="helptip.js">< /script>                |
|   <link type="text/css" rel="StyleSheet" href="helptip.css" />              |
|                                                                             |
|   <a class="helpLink" href="?" onclick="showHelp(event, 'String to show');  |
|      return false">Help</a>                                                 |
|-----------------------------------------------------------------------------|
| Created 2001-09-27 | All changes are in the log above. | Updated 2002-12-02 |
\----------------------------------------------------------------------------*/

function showHelpTip(e, sHtml, bHideSelects) {

   // find anchor element
   var el = e.target || e.srcElement;
   while (el.tagName != "A")
      el = el.parentNode;

   // is there already a tooltip? If so, remove it
   if (el._helpTip) {
      helpTipHandler.hideHelpTip(el);
   }

   helpTipHandler.hideSelects = Boolean(bHideSelects);

   // create element and insert last into the body
   helpTipHandler.createHelpTip(el, sHtml);

   // position tooltip
   helpTipHandler.positionToolTip(e);

   // add a listener to the blur event.
   // When blurred remove tooltip and restore anchor
   el.onblur = helpTipHandler.anchorBlur;
   el.onkeydown = helpTipHandler.anchorKeyDown;
}

var helpTipHandler = {
   hideSelects:   false,

   helpTip:      null,

   showSelects:   function (bVisible) {
      if (!this.hideSelects) return;
      // only IE actually do something in here
      var selects = [];
      if (document.all)
         selects = document.all.tags("SELECT");
      var l = selects.length;
      for   (var i = 0; i < l; i++)
         selects[i].runtimeStyle.visibility = bVisible ? "" : "hidden";
   },

   create:   function () {
      var d = document.createElement("DIV");
      d.className = "help-tooltip";
      d.onmousedown = this.helpTipMouseDown;
      d.onmouseup = this.helpTipMouseUp;
      document.body.appendChild(d);
      this.helpTip = d;
   },

   createHelpTip:   function (el, sHtml) {
      if (this.helpTip == null) {
         this.create();
      }

      var d = this.helpTip;
      d.innerHTML = sHtml;
      d._boundAnchor = el;
      el._helpTip = d;
      return d;
   },

   // Allow clicks on A elements inside tooltip
   helpTipMouseDown:   function (e) {
      var d = this;
      var el = d._boundAnchor;
      if (!e) e = event;
      var t = e.target || e.srcElement;
      while (t.tagName != "A" && t != d)
         t = t.parentNode;
      if (t == d) return;

      el._onblur = el.onblur;
      el.onblur = null;
   },

   helpTipMouseUp:   function () {
      var d = this;
      var el = d._boundAnchor;
      el.onblur = el._onblur;
      el._onblur = null;
      el.focus();
   },

   anchorBlur:   function (e) {
      var el = this;
      helpTipHandler.hideHelpTip(el);
   },

   anchorKeyDown:   function (e) {
      if (!e) e = window.event
      if (e.keyCode == 27) {   // ESC
         helpTipHandler.hideHelpTip(this);
      }
   },

   removeHelpTip:   function (d) {
      d._boundAnchor = null;
      d.style.filter = "none";
      d.innerHTML = "";
      d.onmousedown = null;
      d.onmouseup = null;
      d.parentNode.removeChild(d);
      //d.style.display = "none";
   },

   hideHelpTip:   function (el) {
      var d = el._helpTip;
      /*   Mozilla (1.2+) starts a selection session when moved
         and this destroys the mouse events until reloaded
      d.style.top = -el.offsetHeight - 100 + "px";
      */

      d.style.visibility = "hidden";
      //d._boundAnchor = null;

      el.onblur = null;
      el._onblur = null;
      el._helpTip = null;
      el.onkeydown = null;

      this.showSelects(true);
   },

   positionToolTip:   function (e) {
      this.showSelects(false);
      var scroll = this.getScroll();
      var d = this.helpTip;

      // width
      if (d.offsetWidth >= scroll.width)
         d.style.width = scroll.width - 10 + "px";
      else
         d.style.width = "";

      // left
      if (e.clientX > scroll.width - d.offsetWidth)
         d.style.left = scroll.width - d.offsetWidth + scroll.left + "px";
      else
         d.style.left = e.clientX - 2 + scroll.left + "px";

      // top
      if (e.clientY + d.offsetHeight + 18 < scroll.height)
         d.style.top = e.clientY + 18 + scroll.top + "px";
      else if (e.clientY - d.offsetHeight > 0)
         d.style.top = e.clientY + scroll.top - d.offsetHeight + "px";
      else
         d.style.top = scroll.top + 5 + "px";

      d.style.visibility = "visible";
   },

   // returns the scroll left and top for the browser viewport.
   getScroll:   function () {
      if (document.all && typeof document.body.scrollTop != "undefined") {   // IE model
         var ieBox = document.compatMode != "CSS1Compat";
         var cont = ieBox ? document.body : document.documentElement;
         return {
            left:   cont.scrollLeft,
            top:   cont.scrollTop,
            width:   cont.clientWidth,
            height:   cont.clientHeight
         };
      }
      else {
         return {
            left:   window.pageXOffset,
            top:   window.pageYOffset,
            width:   window.innerWidth,
            height:   window.innerHeight
         };
      }

   }

};