/**
 * $Id: mxEllipse.js,v 1.20 2012-04-04 07:34:50 gaudenz Exp $
 * Copyright (c) 2006-2010, JGraph Ltd
 */
/**
 * Class: mxEllipse
 *
 * Extends <mxShape> to implement an ellipse shape.
 * This shape is registered under <mxConstants.SHAPE_ELLIPSE>
 * in <mxCellRenderer>.
 * 
 * Constructor: mxEllipse
 *
 * Constructs a new ellipse shape.
 * 
 * Parameters:
 * 
 * bounds - <mxRectangle> that defines the bounds. This is stored in
 * <mxShape.bounds>.
 * fill - String that defines the fill color. This is stored in <fill>.
 * stroke - String that defines the stroke color. This is stored in <stroke>.
 * strokewidth - Optional integer that defines the stroke width. Default is
 * 1. This is stored in <strokewidth>.
 */
function mxEllipse(bounds, fill, stroke, strokewidth)
{
	this.bounds = bounds;
	this.fill = fill;
	this.stroke = stroke;
	this.strokewidth = (strokewidth != null) ? strokewidth : 1;
};

/**
 * Extends mxShape.
 */
mxEllipse.prototype = new mxShape();
mxEllipse.prototype.constructor = mxEllipse;

/**
 * Variable: mixedModeHtml
 *
 * Overrides the parent value with false, meaning it will
 * draw in VML in mixed Html mode.
 */
mxEllipse.prototype.mixedModeHtml = false;

/**
 * Variable: preferModeHtml
 *
 * Overrides the parent value with false, meaning it will
 * draw as VML in prefer Html mode.
 */
mxEllipse.prototype.preferModeHtml = false;

/**
 * Function: createVml
 *
 * Creates and returns the VML node to represent this shape.
 */
mxEllipse.prototype.createVml = function()
{
	// Uses an arc not an oval to make sure the
	// textbox fills out the outer bounds of the
	// circle, not just the inner rectangle
	var node = document.createElement('v:arc');
	node.startangle = '0';
	node.endangle = '360';
	this.configureVmlShape(node);

	return node;
};

/**
 * Function: createSvg
 *
 * Creates and returns the SVG node(s) to represent this shape.
 */
mxEllipse.prototype.createSvg = function()
{
	return this.createSvgGroup('ellipse');
};

/**
 * Function: redrawSvg
 *
 * Updates the SVG node(s) to reflect the latest bounds and scale.
 */
mxEllipse.prototype.redrawSvg = function()
{
	if (this.crisp)
	{
		this.innerNode.setAttribute('shape-rendering', 'crispEdges');
	}
	else
	{
		this.innerNode.removeAttribute('shape-rendering');
	}
	
	this.updateSvgNode(this.innerNode);
	this.updateSvgNode(this.shadowNode);
};

/**
 * Function: updateSvgNode
 *
 * Updates the given node to reflect the new <bounds> and <scale>.
 */
mxEllipse.prototype.updateSvgNode = function(node)
{
	if (node != null)
	{
		var strokeWidth = Math.round(Math.max(1, this.strokewidth * this.scale));
		node.setAttribute('stroke-width', strokeWidth);
		
		node.setAttribute('cx', this.bounds.x + this.bounds.width / 2);
		node.setAttribute('cy', this.bounds.y + this.bounds.height / 2);
		node.setAttribute('rx', this.bounds.width / 2);
		node.setAttribute('ry', this.bounds.height / 2);
		
		// Updates the shadow offset
		if (this.shadowNode != null)
		{
			this.shadowNode.setAttribute('transform',  this.getSvgShadowTransform());
		}

		if (this.isDashed)
		{
			var phase = Math.max(1, Math.round(3 * this.scale * this.strokewidth));
			node.setAttribute('stroke-dasharray', phase + ' ' + phase);
		}
	}
};