package 
  {
    import mx.collections.ArrayCollection;
    import mx.containers.Canvas;
    import flash.events.MouseEvent;
    import mx.core.UIComponent;
    import mx.rpc.events.AbstractEvent;
    import mx.controls.Alert;
    
    public class @ax-graphic-flex-diagram-class-Designer
    {
      private var boxes:ArrayCollection = new ArrayCollection();
      private var lines:ArrayCollection = new ArrayCollection();
      private var designArea:Canvas;
      private var isDrawEnable:Boolean = false;
      private var isDrawing:Boolean = false;
      private var templateLine:graphic_flex_diagram_class_Line;
      private var currentFromBox:graphic_flex_diagram_class_Box;
      private var currentToBox:graphic_flex_diagram_class_Box;
      
      // designer is a manager class. 
      public function @ax-graphic-flex-diagram-class-Designer(){        
        templateLine = new graphic_flex_diagram_class_Line();
        templateLine.name="templateLine";
        templateLine.visible = false;
      }
      public function setIsDrawEnable(value:Boolean):void{
        this.isDrawEnable = value;
      }
      public function getIsDrawEnable():Boolean{
        return this.isDrawEnable;
      }
      public function setCurrentFromBox(value:graphic_flex_diagram_class_Box):void{
        this.currentFromBox = value;      
      }
      public function setCurrentToBox(value:graphic_flex_diagram_class_Box):void{
        this.currentToBox = value;  
      }
      public function getBoxList():ArrayCollection{
        return boxes;
      }
      public function getLineList():ArrayCollection{
        return lines;
      }
      private function getId(type:String):String{
        var idString:String  = type + Math.round(Math.random()*10000).toString();
        return idString;
      }
      
      // set design area and adding desing area events.    
      public function setDesignArea(value:Canvas):void{
        this.designArea = value;
        designArea.addChild(templateLine);      
        designArea.addEventListener(MouseEvent.MOUSE_MOVE,mouseMove);
        designArea.addEventListener(MouseEvent.MOUSE_UP,mouseUp);
      }
                  // this method checks mouse up event on the box or not .
                  // if not cancel drawing. 
                  // if there is no excpation add lines
                  public function mouseUp(event:MouseEvent):void{
        if (isDrawEnable){
          try{
            if (graphic_flex_diagram_class_Box(event.currentTarget)!= null){
              addLine();
            }                  
          }
          catch(e:Error){
              cancelDrawing();          
          }        
        }      
      }
      //when mouse move on the design area drawing template line if isDrawing true
      public function mouseMove(event:MouseEvent):void{
        if (isDrawing){
          drawLine();  
        }
      }
      // create box 
      public function addBox(x:int, y:int):void{
        var newBox:graphic_flex_diagram_class_Box = new graphic_flex_diagram_class_Box();
        var id:String = getId("Box");
        newBox.setDesigner(this);
        newBox.create(x,y,id);
        boxes.addItem(newBox);     
        designArea.addChild(newBox);
      } 
      // this method works when mouse down on the box 
      // it sets first point coordinae of template line
      public function prepareDrawing():void{    
        if (isDrawEnable){
          templateLine.graphics.clear();
          templateLine.setX1(designArea.mouseX);
          templateLine.setY1(designArea.mouseY);
          templateLine.visible = true;
          isDrawing = true;      
        }  
      }
      // this methods set second coordinate of template line and draw
      public function drawLine():void{   
        if (isDrawing){
          templateLine.setX2(designArea.mouseX);
          templateLine.setY2(designArea.mouseY);
          templateLine.draw();
        }
      }
      
      // this methods create new line and add line to box and designer
      public function addLine():void{ 
        if (isDrawing){
          var newLine:graphic_flex_diagram_class_Line = new graphic_flex_diagram_class_Line();
          newLine.setId(getId("Line"));
          newLine.setFromBox(currentFromBox);
          newLine.setToBox(currentToBox);
          newLine.draw();        
          currentFromBox.addFromLine(newLine);
          currentToBox.addToLine(newLine);          
          lines.addItem(newLine);
          designArea.addChild(newLine);
          templateLine.visible = false;        
          isDrawEnable = false;
          isDrawing = false;        
        }
        else{
          cancelDrawing();
        }
      }
      // this methods cancel drawing
      public function cancelDrawing():void{
        templateLine.visible = false;
        isDrawEnable = false;
        isDrawing = false;
      }
    }
  }