/* 
Copyright (c) 2005 Tim Taylor Consulting <http://tool-man.org/>

Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE 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.
 */

ToolMan._coordinatesFactory = {

	create : function(x, y) {
		// FIXME: Safari won't parse 'throw' and aborts trying to do anything with this file
		//if (isNaN(x) || isNaN(y)) throw "invalid x,y: " + x + "," + y
		return new _ToolManCoordinate(this, x, y)
	},

	origin : function() {
		return this.create(0, 0)
	},

	/*
	 * FIXME: Safari 1.2, returns (0,0) on absolutely positioned elements
	 */
	topLeftPosition : function(element) {
		var left = parseInt(ToolMan.css().readStyle(element, "left"))
		var left = isNaN(left) ? 0 : left
		var top = parseInt(ToolMan.css().readStyle(element, "top"))
		var top = isNaN(top) ? 0 : top

		return this.create(left, top)
	},

	bottomRightPosition : function(element) {
		return this.topLeftPosition(element).plus(this._size(element))
	},

	topLeftOffset : function(element) {
		var offset = this._offset(element) 

		var parent = element.offsetParent
		while (parent) {
			offset = offset.plus(this._offset(parent))
			parent = parent.offsetParent
		}
		return offset
	},

	bottomRightOffset : function(element) {
		return this.topLeftOffset(element).plus(
				this.create(element.offsetWidth, element.offsetHeight))
	},

	scrollOffset : function() {
		if (window.pageXOffset) {
			return this.create(window.pageXOffset, window.pageYOffset)
		} else if (document.documentElement) {
			return this.create(
					document.body.scrollLeft + document.documentElement.scrollLeft, 
					document.body.scrollTop + document.documentElement.scrollTop)
		} else if (document.body.scrollLeft >= 0) {
			return this.create(document.body.scrollLeft, document.body.scrollTop)
		} else {
			return this.create(0, 0)
		}
	},

	clientSize : function() {
		if (window.innerHeight >= 0) {
			return this.create(window.innerWidth, window.innerHeight)
		} else if (document.documentElement) {
			return this.create(document.documentElement.clientWidth,
					document.documentElement.clientHeight)
		} else if (document.body.clientHeight >= 0) {
			return this.create(document.body.clientWidth,
					document.body.clientHeight)
		} else {
			return this.create(0, 0)
		}
	},

	mousePosition : function(event) {
		event = ToolMan.events().fix(event)
		return this.create(event.clientX, event.clientY)
	},

	mouseOffset : function(event) {
		event = ToolMan.events().fix(event)
		if (event.pageX >= 0 || event.pageX < 0) {
			return this.create(event.pageX, event.pageY)
		} else if (event.clientX >= 0 || event.clientX < 0) {
			return this.mousePosition(event).plus(this.scrollOffset())
		}
	},

	_size : function(element) {
	/* TODO: move to a Dimension class */
		return this.create(element.offsetWidth, element.offsetHeight)
	},

	_offset : function(element) {
		return this.create(element.offsetLeft, element.offsetTop)
	}
}

function _ToolManCoordinate(factory, x, y) {
	this.factory = factory
	this.x = isNaN(x) ? 0 : x
	this.y = isNaN(y) ? 0 : y
}

_ToolManCoordinate.prototype = {
	toString : function() {
		return "(" + this.x + "," + this.y + ")"
	},

	plus : function(that) {
		return this.factory.create(this.x + that.x, this.y + that.y)
	},

	minus : function(that) {
		return this.factory.create(this.x - that.x, this.y - that.y)
	},

	min : function(that) {
		return this.factory.create(
				Math.min(this.x , that.x), Math.min(this.y , that.y))
	},

	max : function(that) {
		return this.factory.create(
				Math.max(this.x , that.x), Math.max(this.y , that.y))
	},

	constrainTo : function (one, two) {
		var min = one.min(two)
		var max = one.max(two)

		return this.max(min).min(max)
	},

	distance : function (that) {
		return Math.sqrt(Math.pow(this.x - that.x, 2) + Math.pow(this.y - that.y, 2))
	},

	reposition : function(element) {
		element.style["top"] = this.y + "px"
		element.style["left"] = this.x + "px"
	}
}