/*
 * ***** BEGIN LICENSE BLOCK *****
 * Version: ZAPL 1.1
 * 
 * The contents of this file are subject to the Zimbra AJAX Public
 * License Version 1.1 ("License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.zimbra.com/license
 * 
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 * 
 * The Original Code is: Zimbra AJAX Toolkit.
 * 
 * The Initial Developer of the Original Code is Zimbra, Inc.
 * Portions created by Zimbra are Copyright (C) 2005 Zimbra, Inc.
 * All Rights Reserved.
 * 
 * Contributor(s):
 * 
 * ***** END LICENSE BLOCK *****
 */

function DwtUiEvent(init) {
	if (arguments.length == 0) return;
	DwtEvent.call(this, true);
	this.reset();
}

DwtUiEvent.prototype = new DwtEvent;
DwtUiEvent.prototype.constructor = DwtUiEvent;

DwtUiEvent.prototype.toString = 
function() {
	return "DwtUiEvent";
}

DwtUiEvent.prototype.reset =
function() {
	this.dwtObj = null
	this.altKey = false;
	this.ctrlKey = false;
	this.shiftKey = false;
	this.target = null;
	this.type = null;
	this.docX = -1;
	this.docY = -1;
	this.elementX = -1;
	this.elementY = -1;
	this._stopPropagation = false;
	this._returnValue = true;
}

DwtUiEvent.getEvent =
function(ev) {
	return (ev) ? ev : ((window.event) ? window.event : null);
}

DwtUiEvent.getTarget =
function(ev)  {
	ev = DwtUiEvent.getEvent(ev);
	if (ev.target) {
		/* if text node (like on Safari) return parent */
		if (ev.target.nodeType == 3) {
			return ev.target.parentNode;
		} else {
			return ev.target;
		}
	} else if (ev.srcElement) {
		return ev.srcElement;
	} else {
		return null;
	}
}

/**
* Returns the first element with a non-null value for the given property, working its way up the element chain.
*
* @param ev		a UI event
* @param prop	the name of a property
* @returns		an element
*/
DwtUiEvent.getTargetWithProp =
function(ev, prop)  {
	var htmlEl = DwtUiEvent.getTarget(ev);
	while (htmlEl) {
		if (htmlEl[prop] != null) {
			return htmlEl;
		}
		htmlEl = htmlEl.parentNode;
	}
	return null;
}

/**
* Returns the first element with a non-null value for the given properties, working its way up the element chain.
*
* @param ev		a UI event
* @param props	a list of property names
* @returns		an element
*/
DwtUiEvent.getTargetWithProps =
function(ev, props)  {
	var htmlEl = DwtUiEvent.getTarget(ev);
	while (htmlEl) {
		var okay = true;
		for (var i in props) {
			if (htmlEl[props[i]] == null) {
				htmlEl = htmlEl.parentNode;
				okay = false;
				break;
			}
		}
		if (okay)
			return htmlEl;
	}
	return null;
}

DwtUiEvent.getDwtObjFromEvent =
function(ev) {
	var htmlEl = DwtUiEvent.getTargetWithProp(ev, "dwtObj");
	return htmlEl ? Dwt.getObjectFromElement(htmlEl) : null;
}

DwtUiEvent.getDwtObjWithProp =
function(ev, prop) {
	var htmlEl = DwtUiEvent.getTargetWithProps(ev, ["dwtObj", prop]);
	return htmlEl ? Dwt.getObjectFromElement(htmlEl) : null;
}

DwtUiEvent.copy = 
function(dest, src) {
	dest.altKey = src.altKey;
	dest.ctrlKey = src.ctrlKey;
	dest.shiftKey = src.shiftKey;
	dest.target = src.target;
	dest.type = src.type;
	dest.dwtObj = src.dwtObj;
	dest.docX = src.docX;
	dest.docY = src.docY;
	dest.elementX = src.elementX;
	dest.elementY = src.elementY;
	dest._stopPropagation = src._stopPropagation;
	dest._returnValue = src._returnValue;
}

DwtUiEvent.prototype.setFromDhtmlEvent =
function(ev) {
	ev = DwtUiEvent.getEvent(ev);
	if (!ev) return;
	this.altKey = ev.altKey;
	this.ctrlKey = ev.ctrlKey;
	this.shiftKey = ev.shiftKey;
	this.type = ev.type;
	this.target = DwtUiEvent.getTarget(ev);
	var target = this.target;
	while (target != null) {
		if (target.dwtObj != null) {
			this.dwtObj = Dwt.getObjectFromElement(target);
			break;
		}
		target = target.parentNode;
	}

	// Compute document coordinates
	if (ev.pageX != null) {
		this.docX = ev.pageX;
		this.docY = ev.pageY;
	} else if (ev.clientX != null) {
		this.docX = ev.clientX + document.body.scrollLeft - document.body.clientLeft;
		this.docY = ev.clientY + document.body.scrollTop - document.body.clientTop;
		if (document.body.parentElement) {
				var bodParent = document.body.parentElement;
				this.docX += bodParent.scrollLeft - bodParent.clientLeft;
				this.docY += bodParent.scrollTop - bodParent.clientTop;
		}
	}
	// Compute Element coordinates
	if (ev.offsetX != null) {
		this.elementX = ev.offsetX;
		this.elementY = ev.offsetY;
	} else if (ev.layerX != null) {
		this.elementX = ev.layerX;
		this.elementY = ev.layerY;
	} else { // fail hard for others
		this.elementX = Dwt.DEFAULT;
		this.elementY = Dwt.DEFAULT;
	}
	return ev;
}

DwtUiEvent.prototype.setToDhtmlEvent =
function(ev) {
	DwtUiEvent.setBehaviour(ev, this._stopPropagation, this._returnValue);	
}

DwtUiEvent.setBehaviour =
function(ev, stopPropagation, allowDefault) {
	ev = DwtUiEvent.getEvent(ev);
	
	// stopPropagation is referring to the function found in Mozilla's event object
	if (ev.stopPropagation != null) {
		if (stopPropagation)
			ev.stopPropagation();
		if (!allowDefault)
			ev.preventDefault();
	} else {
		// IE only..
		ev.returnValue = allowDefault; 
		ev.cancelBubble = stopPropagation;
	}
}