text: dojo.provide("dojox.sketch.SingleArrowAnnotation");
  dojo.require("dojox.sketch.Annotation");
  dojo.require("dojox.sketch.Anchor");
  
  (function(){
  	var ta=dojox.sketch;
  	ta.SingleArrowAnnotation=function(figure, id){
  		ta.Annotation.call(this, figure, id);
  		this.transform={ dx:0, dy:0 };
  		this.start={x:0, y:0};
  		this.control={x:100, y:-50};
  		this.end={x:200, y:0};
  		this.textPosition={ x:0, y:0 };
  		this.textOffset=4;
  		this.textAlign="middle";
  		this.textYOffset=10;
  		this.rotation=0;
  
  //		this.property('label',this.id);
  //		this.label=this.id;
  		this.pathShape=null;
  		this.arrowhead=null;
  		this.arrowheadGroup=null;
  		this.labelShape=null;
  
  		this.anchors.start=new ta.Anchor(this, "start");
  		this.anchors.control=new ta.Anchor(this, "control");
  		this.anchors.end=new ta.Anchor(this, "end");
  	};
  	ta.SingleArrowAnnotation.prototype=new ta.Annotation;
  	var p=ta.SingleArrowAnnotation.prototype;
  	p.constructor=ta.SingleArrowAnnotation;
  
  	p.type=function(){ return 'SingleArrow'; };
  	p.getType=function(){ return ta.SingleArrowAnnotation; };
  
  	//	helper functions
  	p._rot=function(){
  		//	arrowhead rotation
  		var opp=this.start.y-this.control.y;
  		var adj=this.start.x-this.control.x;
  		if(!adj){ adj=1; }
  		this.rotation=Math.atan(opp/adj);
  	};
  	p._pos=function(){
  		//	text position
  		var offset=this.textOffset, x=0, y=0;
  		var slope=this.calculate.slope(this.control, this.end);
  		if(Math.abs(slope)>=1){
  			x=this.end.x+this.calculate.dx(this.control, this.end, offset);
  			if(this.control.y>this.end.y){ y=this.end.y-offset; }
  			else{ y=this.end.y+offset+this.textYOffset; }
  		} else if(slope==0){
  			x=this.end.x+offset;
  			y=this.end.y+this.textYOffset;
  		} else {
  			if(this.start.x>this.end.x){
  				x=this.end.x-offset;
  				this.textAlign="end";
  			} else {
  				x=this.end.x+offset;
  				this.textAlign="start";
  			}
  			if(this.start.y<this.end.y){
  				y=this.end.y+this.calculate.dy(this.control, this.end, offset)+this.textYOffset;
  			} else { 
  				y=this.end.y+this.calculate.dy(this.control, this.end, -offset);
  			}
  		}
  		this.textPosition={ x:x, y:y };
  	};
  	
  	p.apply=function(obj){
  		if(!obj){ return; }
  		if(obj.documentElement){ obj=obj.documentElement; }
  		this.readCommonAttrs(obj);
  		
  		for(var i=0; i<obj.childNodes.length; i++){
  			var c=obj.childNodes[i];
  			if(c.localName=="text"){ 
  				this.property('label',c.childNodes.length?c.childNodes[0].nodeValue:'');
  			}
  			else if(c.localName=="path"){
  				//	the line
  				var d=c.getAttribute('d').split(" ");
  				var s=d[0].split(",");
  				this.start.x=parseFloat(s[0].substr(1),10);
  				this.start.y=parseFloat(s[1],10);
  				s=d[1].split(",");
  				this.control.x=parseFloat(s[0].substr(1),10);
  				this.control.y=parseFloat(s[1],10);
  				s=d[2].split(",");
  				this.end.x=parseFloat(s[0],10);
  				this.end.y=parseFloat(s[1],10);
  			}
  		}
  	};
  	p.initialize=function(obj){
  		//	create, based on passed DOM node if available.
  		var font=(ta.Annotation.labelFont)?ta.Annotation.labelFont:{family:"Times", size:"16px"};
  		this.apply(obj);
  
  		//	calculate the other positions
  		this._rot();
  		this._pos();
  
  		//	rotation matrix
  		var rot=this.rotation;
  		if(this.control.x>=this.end.x&&this.control.x<this.start.x){ rot+=Math.PI; }
  		var tRot=dojox.gfx.matrix.rotate(rot);
  
  		//	draw the shapes
  		this.shape=this.figure.group.createGroup();
  		this.shape.getEventSource().setAttribute("id", this.id);
  		if(this.transform.dx||this.transform.dy){ this.shape.setTransform(this.transform); }
  
  		this.pathShape=this.shape.createPath("M"+this.start.x+","+this.start.y+" Q"+this.control.x+","+this.control.y+" "+this.end.x+","+this.end.y+" l0,0")
  			.setStroke(this.property('stroke'));
  
  		this.arrowheadGroup=this.shape.createGroup().setTransform({ dx:this.start.x, dy:this.start.y }).applyTransform(tRot);
  		this.arrowhead=this.arrowheadGroup.createPath("M0,0 l20,-5 -3,5 3,5 Z").setFill(this.property('fill'));
  
  		this.labelShape=this.shape.createText({
  				x:this.textPosition.x, 
  				y:this.textPosition.y, 
  				text:this.property('label'), 
  				align:this.textAlign
  			})
  			.setFont(font)
  			.setFill(this.property('fill'));
  	};
  
  	p.destroy=function(){
  		if(!this.shape){ return; }
  		this.arrowheadGroup.remove(this.arrowhead);
  		this.shape.remove(this.arrowheadGroup);
  		this.shape.remove(this.pathShape);
  		this.shape.remove(this.labelShape);
  		this.figure.group.remove(this.shape);
  		this.shape=this.pathShape=this.labelShape=this.arrowheadGroup=this.arrowhead=null;
  	};
  
  	p.draw=function(obj){
  		this.apply(obj);
  		this._rot();
  		this._pos();
  
  		//	rotation matrix
  		var rot=this.rotation;
  		if(this.control.x<this.start.x){ rot+=Math.PI; }
  		var tRot=dojox.gfx.matrix.rotate(rot);
  
  		this.shape.setTransform(this.transform);
  		this.pathShape.setShape("M"+this.start.x+","+this.start.y+" Q"+this.control.x+","+this.control.y+" "+this.end.x+","+this.end.y+" l0,0")
  			.setStroke(this.property('stroke'));
  
  		this.arrowheadGroup.setTransform({dx:this.start.x,dy:this.start.y}).applyTransform(tRot);
  		this.arrowhead.setFill(this.property('fill'));
  
  		this.labelShape.setShape({
  				x:this.textPosition.x, 
  				y:this.textPosition.y, 
  				text:this.property('label'), 
  				align:this.textAlign
  			})
  			.setFill(this.property('fill'));
  	};
  
  	p.getBBox=function(){
  		var x=Math.min(this.start.x, this.control.x, this.end.x);
  		var y=Math.min(this.start.y, this.control.y, this.end.y);
  		var w=Math.max(this.start.x, this.control.x, this.end.x)-x;
  		var h=Math.max(this.start.y, this.control.y, this.end.y)-y;
  		return { x:x, y:y, width:w, height:h };
  	};
  
  	p.serialize=function(){
  		var s=this.property('stroke');
  		var r=this.rotation*(180/Math.PI);
  		if(this.start.x>this.end.x){ r-=180; }
  		r=Math.round(r*Math.pow(10,4))/Math.pow(10,4);
  		return '<g '+this.writeCommonAttrs()+'>'
  			+ '<path style="stroke:'+s.color+';stroke-width:'+s.width+';fill:none;" d="'
  			+ "M"+this.start.x+","+this.start.y+" "
  			+ "Q"+this.control.x+","+this.control.y+" "
  			+ this.end.x+","+this.end.y
  			+ '" />'
  			+ '<g transform="translate(' + this.start.x + "," + this.start.y + ") "
  			+ 'rotate(' + r + ')">'
  			+ '<path style="fill:'+s.color+';" d="M0,0 l20,-5, -3,5, 3,5 Z" />'
  			+ '</g>'
  			+ '<text style="fill:'+s.color+';text-anchor:'+this.textAlign+'" font-weight="bold" '
  			+ 'x="' + this.textPosition.x + '" '
  			+ 'y="' + this.textPosition.y + '">'
  			+ this.property('label')
  			+ '</text>'
  			+ '</g>';
  	};
  
  	ta.Annotation.register("SingleArrow");
  })();
  