/*----------------------------------------------------------------------------\
|                               Help Tip 1.1                                  |
|-----------------------------------------------------------------------------|
|                         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.              |
|-----------------------------------------------------------------------------|
| 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 2002-10-04 |
\----------------------------------------------------------------------------*/

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;
		d.style.visibility = "hidden";
		d.style.top = - el.offsetHeight - 100 + "px"
		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;
		
		var dw = (window.innerWidth || document.documentElement.offsetWidth) - 25;
		
		if (d.offsetWidth >= dw)
			d.style.width = dw - 10 + "px";
		else
			d.style.width = "";
		
		if (e.clientX > dw - d.offsetWidth)
			d.style.left = dw - d.offsetWidth + scroll.x + "px";
		else
			d.style.left = e.clientX - 2 + scroll.x + "px";
		d.style.top = e.clientY + 18 + scroll.y + "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 {x : cont.scrollLeft, y : cont.scrollTop};
		}
		else {
			return {x : window.pageXOffset, y : window.pageYOffset};
		}
		
	}

};