package measurements
{
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.display.MovieClip;
    
    import flash.display.BlendMode;
    
    import flash.display.LineScaleMode;
    import flash.display.CapsStyle;
    import flash.display.JointStyle;
    import flash.display.Shape;
    
    import flash.display.Stage;
    import flash.display.Graphics;
    import flash.display.Sprite;
    import flash.display.DisplayObject; 
    import flash.display.DisplayObjectContainer; 
    import flash.display.SimpleButton;
    
    import flash.geom.Point;

    import canvasses.CurvedCanvas;
    import measurements.Measurement;
    import measurements.Handle;
    import measurements.Anchor;

    public dynamic class CurvedMeasurement extends Measurement
    {
        
        // ------------------------------------------------------------------------------------------------------------------------
        // Variables
        // ------------------------------------------------------------------------------------------------------------------------

            // line
                private var segments            :Number;
                private var handle1             :Handle;
                private var handle2             :Handle;
                private var currentHandle       :Handle;
                
    
        // ------------------------------------------------------------------------------------------------------------------------
        // Constructor
        // ------------------------------------------------------------------------------------------------------------------------
        
            public function CurvedMeasurement(canvas:CurvedCanvas, index:uint = 0, start:Boolean = true)
            {
                super(canvas, index);
                this.LINE_COLOR    = 0xff0000;
                this.segments      = 100;

            }
        
        // ------------------------------------------------------------------------------------------------------------------------
        // Create
        // ------------------------------------------------------------------------------------------------------------------------

            public function create(anchor1Pos:Point, anchor2Pos:Point, handle1Pos:Point, handle2Pos:Point):void
            {
        
                trace('canvas:' + this.canvas);
        
                // objects
                    anchor1                = new Anchor();
                    anchor2                = new Anchor();
                    anchor1.name           = 'anchor1';
                    anchor2.name           = 'anchor2';
                    currentAnchor          = anchor2;
                    
                    handle1                = new Handle();
                    handle2                = new Handle();
                    handle1.name           = 'handle1';
                    handle2.name           = 'handle2';
                    currentHandle          = handle2;
                    
    
                    handle1.blendMode      = BlendMode.LAYER;
                // positions
                    anchor1.setPos(anchor1Pos.x, anchor1Pos.y);
                    anchor2.setPos(anchor2Pos.x, anchor2Pos.y);
                    handle1.setPos(handle1Pos.x, handle1Pos.y);
                    handle2.setPos(handle2Pos.x, handle2Pos.y);
            
                // display
                    this.canvas.addChild(this);
                    addChild(anchor1);
                    addChild(anchor2);
                    addChild(handle1);
                    addChild(handle2);
                    
                    rotateHandles(anchor1, handle1);
                    rotateHandles(anchor2, handle2);
                    
                    draw();
                
                // interactivity
                    addInteractivity()
    
            }
            
    
        // ------------------------------------------------------------------------------------------------------------------------
        // Handlers
        // ------------------------------------------------------------------------------------------------------------------------
   
            private function downHandler(evt:Event):Boolean
            {
                
                // events
                    evt.stopPropagation();
                    
                //do it
                    if(evt.target.constructor == Handle)
                    {
                        currentHandle = Handle(evt.target);
                        setChildIndex(currentHandle, 1);
                        canvas.stage.addEventListener(MouseEvent.MOUSE_MOVE, this.dragHandle);
                    }
                    else if(evt.target.constructor == Anchor)
                    {
                        currentHandle = Handle(Anchor(evt.target));
                        setChildIndex(currentHandle, 1);
                        canvas.stage.addEventListener(MouseEvent.MOUSE_MOVE, this.dragHandle);
                    }
                // return
                    return true;
            }
            
            private function upHandler(evt:Event):void
            {
                canvas.stage.removeEventListener(MouseEvent.MOUSE_MOVE, this.dragHandle);
            }

            private function dragHandle(evt:MouseEvent):void
            {
                // trace(currentHandle.name, currentHandle.constructor == Handle)
                
                currentHandle.x        = mouseX;
                currentHandle.y        = mouseY;
                
                this.rotateHandles(anchor1, handle1);
                this.rotateHandles(anchor2, handle2);
                draw();
                //this.updateLength();
                
                evt.updateAfterEvent();
                
            }
            
        // ------------------------------------------------------------------------------------------------------------------------
        // Utilities
        // ------------------------------------------------------------------------------------------------------------------------
    
            override public function draw():void
            {
                
                // variables
                    var length        :Number        = 0;
                    var step          :Number        = 1 / segments;
                    
                    var x             :Number;
                    var y             :Number;
                    
                    var xOld          :Number        = anchor1.x;
                    var yOld          :Number        = anchor1.y;
                    
                    var dx            :Number;
                    var dy            :Number;
                    
                // draw line
                    gfx.clear()
                    gfx.moveTo(xOld, yOld);
                    gfx.lineStyle(LINE_WIDTH, LINE_COLOR, LINE_ALPHA, false, LineScaleMode.VERTICAL, CapsStyle.NONE, JointStyle.MITER, 10);
                    
                // This loops draws each step of the curve
                    for (var i:Number = 0; i <= 1; i += step)
                    {
                        // position
                            x             = Math.pow(i, 3) * (anchor2.x + 3 * (handle1.x - handle2.x) - anchor1.x) + 3 * Math.pow(i, 2) * (anchor1.x - 2 * handle1.x + handle2.x) + 3 * i * (handle1.x - anchor1.x) + anchor1.x;
                            y             = Math.pow(i, 3) * (anchor2.y + 3 * (handle1.y - handle2.y) - anchor1.y) + 3 * Math.pow(i, 2) * (anchor1.y - 2 * handle1.y + handle2.y) + 3 * i * (handle1.y - anchor1.y) + anchor1.y;
                            gfx.lineTo(x, y);
                            
                        // length
                            dx            = x - xOld;
                            dy            = y - yOld;
                            xOld          = x;
                            yOld          = y;
                            length        += Math.sqrt(dx * dx + dy * dy);
                    } 
                    
                // As a final step, make sure the curve ends on the second anchor
                
                    // position
                        gfx.lineTo(anchor2.x, anchor2.y);
                        
                    // length
                        dx                = anchor2.x - xOld;
                        dy                = anchor2.y - yOld;
                        length            += Math.sqrt(dx * dx + dy * dy);
                        this.length       = length;
                        
                        
                // draw handles
                    gfx.lineStyle(LINE_WIDTH / 2, LINE_COLOR, LINE_ALPHA / 2, false, LineScaleMode.VERTICAL, CapsStyle.NONE, JointStyle.MITER, 10);
                    
                    gfx.moveTo(anchor1.x, anchor1.y);
                    gfx.lineTo(handle1.x, handle1.y);
                    
                    gfx.moveTo(anchor2.x, anchor2.y);
                    gfx.lineTo(handle2.x, handle2.y);
            }
            
            private function rotateHandles(a:DisplayObject, b:DisplayObject)
            {
                var dx            = a.x - b.x;
                var dy            = a.y - b.y;
                var r             = Math.atan2(dy, dx) * 180 /  Math.PI;
                a.rotation        = r;
                b.rotation        = r;
            }
            
        }
        

}