/*
Script: Element.Dimensions.js
	Contains methods to work with size, scroll, or positioning of Elements and the window object.

License:
	MIT-style license.

Credits:
	- Element positioning based on the [qooxdoo](http://qooxdoo.org/) code and smart browser fixes, [LGPL License](http://www.gnu.org/licenses/lgpl.html).
	- Viewport dimensions based on [YUI](http://developer.yahoo.com/yui/) code, [BSD License](http://developer.yahoo.com/yui/license.html).
*/

(function(){

Element.implement({

	scrollTo: function(x, y){
		if (isBody(this)){
			this.getWindow().scrollTo(x, y);
		} else {
			this.scrollLeft = x;
			this.scrollTop = y;
		}
		return this;
	},

	getSize: function(){
		if (isBody(this)) return this.getWindow().getSize();
		return {x: this.offsetWidth, y: this.offsetHeight};
	},

	getScrollSize: function(){
		if (isBody(this)) return this.getWindow().getScrollSize();
		return {x: this.scrollWidth, y: this.scrollHeight};
	},

	getScroll: function(){
		if (isBody(this)) return this.getWindow().getScroll();
		return {x: this.scrollLeft, y: this.scrollTop};
	},

	getScrolls: function(){
		var element = this, position = {x: 0, y: 0};
		while (element && !isBody(element)){
			position.x += element.scrollLeft;
			position.y += element.scrollTop;
			element = element.parentNode;
		}
		return position;
	},
	
	getOffsetParent: function(){
		var element = this;
		if (isBody(element)) return null; 
		if (!Browser.Engine.trident) return element.offsetParent;
		while ((element = element.parentNode) && !isBody(element)){ 
			if (styleString(element, 'position') != 'static') return element;
		} 
		return null;
	},

	getOffsets: function(){
		var element = this, position = {x: 0, y: 0};
		if (isBody(this)) return position;

		while (element && !isBody(element)){
			position.x += element.offsetLeft;
			position.y += element.offsetTop;

			if (Browser.Engine.gecko){
				if (!borderBox(element)){
					position.x += leftBorder(element);
					position.y += topBorder(element);
				}
				var parent = element.parentNode;
				if (parent && styleString(parent, 'overflow') != 'visible'){
					position.x += leftBorder(parent);
					position.y += topBorder(parent);
				}
			} else if (element != this && (Browser.Engine.trident || Browser.Engine.webkit)){
				position.x += leftBorder(element);
				position.y += topBorder(element);
			}

			element = element.offsetParent;
			if (Browser.Engine.trident){
				while (element && !element.currentStyle.hasLayout) element = element.offsetParent;
			}
		}
		if (Browser.Engine.gecko && !borderBox(this)){
			position.x -= leftBorder(this);
			position.y -= topBorder(this);
		}
		return position;
	},

	getPosition: function(relative){
		if (isBody(this)) return {x: 0, y: 0};
		var offset = this.getOffsets(), scroll = this.getScrolls();
		var position = {x: offset.x - scroll.x, y: offset.y - scroll.y};
		var relativePosition = (relative && (relative = $(relative))) ? relative.getPosition() : {x: 0, y: 0};
		return {x: position.x - relativePosition.x, y: position.y - relativePosition.y};
	},

	getCoordinates: function(element){
		if (isBody(this)) return this.getWindow().getCoordinates();
		var position = this.getPosition(element), size = this.getSize();
		var obj = {left: position.x, top: position.y, width: size.x, height: size.y};
		obj.right = obj.left + obj.width;
		obj.bottom = obj.top + obj.height;
		return obj;
	},

	computePosition: function(obj){
		return {left: obj.x - styleNumber(this, 'margin-left'), top: obj.y - styleNumber(this, 'margin-top')};
	},

	position: function(obj){
		return this.setStyles(this.computePosition(obj));
	}

});

// private methods

var styleString = Element.getComputedStyle;

function styleNumber(element, style){
	return styleString(element, style).toInt() || 0;
};

function borderBox(element){
	return styleString(element, '-moz-box-sizing') == 'border-box';
};

function topBorder(element){
	return styleNumber(element, 'border-top-width');
};

function leftBorder(element){
	return styleNumber(element, 'border-left-width');
};

function isBody(element){
	return (/^(?:body|html)$/i).test(element.tagName);
};

function getCompatElement(element){
	var doc = element.getDocument();
	return (!doc.compatMode || doc.compatMode == 'CSS1Compat') ? doc.html : doc.body;
};

})();

//aliases

Native.implement([Window, Document, Element], {

	getHeight: function(){
		return this.getSize().y;
	},

	getWidth: function(){
		return this.getSize().x;
	},

	getScrollTop: function(){
		return this.getScroll().y;
	},

	getScrollLeft: function(){
		return this.getScroll().x;
	},

	getScrollHeight: function(){
		return this.getScrollSize().y;
	},

	getScrollWidth: function(){
		return this.getScrollSize().x;
	},

	getTop: function(){
		return this.getPosition().y;
	},

	getLeft: function(){
		return this.getPosition().x;
	}

});



/*
Script: JSON.js
	JSON encoder and decoder.

License:
	MIT-style license.

See Also:
	<http://www.json.org/>
*/

var JSON = new Hash({

	encode: function(obj){
		switch ($type(obj)){
			case 'string':
				return '"' + obj.replace(/[\x00-\x1f\\"]/g, JSON.$replaceChars) + '"';
			case 'array':
				return '[' + String(obj.map(JSON.encode).filter($defined)) + ']';
			case 'object': case 'hash':
				var string = [];
				Hash.each(obj, function(value, key){
					var json = JSON.encode(value);
					if (json) string.push(JSON.encode(key) + ':' + json);
				});
				return '{' + string + '}';
			case 'number': case 'boolean': return String(obj);
			case false: return 'null';
		}
		return null;
	},

	$specialChars: {'\b': '\\b', '\t': '\\t', '\n': '\\n', '\f': '\\f', '\r': '\\r', '"' : '\\"', '\\': '\\\\'},

	$replaceChars: function(chr){
		return JSON.$specialChars[chr] || '\\u00' + Math.floor(chr.charCodeAt() / 16).toString(16) + (chr.charCodeAt() % 16).toString(16);
	},

	decode: function(string, secure){
		if ($type(string) != 'string' || !string.length) return null;
		if (secure && !(/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(string.replace(/\\./g, '@').replace(/"[^"\\\n\r]*"/g, ''))) return null;
		return eval('(' + string + ')');
	}

});

Native.implement([Hash, Array, String, Number], {

	toJSON: function(){
		return JSON.encode(this);
	}

});