/**
 * Keeps track of all objects/UML components that need to be represented and 
 * draws them. Will also be responsible for allowing dragging of UML components.
 *
 * @author Eric Liebowitz
 * @version 22jun11
 */
package simple_uml.view.canvas;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

import simple_uml.model.MainModel;
import simple_uml.model.SumlClassModel;

import java.util.Vector;

public class SumlCanvas extends Canvas
{
   /**
    * Width of rectangle used for clicking on objects to select them. If you
    * change this, be sure to make it an even number.
    */
   private static final int SELECT_WIDTH = 4;

   /**
    * Height of rectangle used for clicking on objects to select them. If you 
    * change this, be sure to make it an even number.
    */
   private static final int SELECT_HEIGHT = 4;

   /**
    * Rectangle used for making selections based on intersection w/ it
    */
   private static final Rectangle rSelector = 
      new Rectangle(SELECT_WIDTH, SELECT_HEIGHT);

   /**
    * Default, monospace font text can use to draw
    */
   protected static final Font MONO_FONT = 
      new Font ("Monospaced", Font.BOLD, 12);

   /**
    * Reference to the main model.
    */
   private MainModel mm;

   /**
    * List of shapes on this canvas that we'll be drawing.
    */
   private Vector<SumlShape> shapes = new Vector<SumlShape>();

   public SumlCanvas (MainModel mm)
   {
      super ();
      
      this.mm = mm;
      shapes.add(new SumlClassView(this, MainModel.ANIMAL));
      shapes.add(new SumlClassView(this, MainModel.HORSE));
      shapes.add(new SumlClassView(this, MainModel.ZOMBIE_HORSE));

      MovingListener ml = new MovingListener(this);
      addMouseListener(ml);
      addMouseMotionListener(ml);
   }

   /**
    * Gives you the shape under a given coordinate. Creates a
    * SELECT_WIDTH x SELECT_HEIGHT rectangle centered around the given point
    * and tests all the shapes on this canvas for intersection. 
    *
    * @param x The x-coord of your selection
    * @param y the y-coord of your selection
    *
    * @return The shape under your selection. If no shape is there, you'll get 
    *         null.
    */
   public SumlShape getSelectionAt (int x, int y)//==>
   {
      rSelector.setLocation(x - 2, y - 2);
      SumlShape r = null;

      for (SumlShape s: this.shapes)
      {
         if (s.intersects(rSelector))
         {
            r = s;
         }
      }

      return r;
   }//<==

   /**
    * Looks through all our shapes for one with a particular model backing it.
    * TODO: I assume everything is a SumlClassModel right now. I have to create
    * a generic class which all shape models can extend.
    *
    * @param cm The model to look for in our views/Shapes.
    */
   public SumlShape getClassShape (SumlClassModel cm)//==>
   {
      SumlShape r = null;
      for (SumlShape s: this.shapes)
      {
         if (s.getModel().equals(cm))
         {
            r = s;
         }
      }
      return r;
   }//<==

   /**
    * Goes through all the shapes in this canvas and paints each one.
    *
    * @param g Graphics object to paint  stuff with. We'll cast it to a 
    *          Graphics2D object before passing it to the shapes to draw.
    */
   public void paint (Graphics g)//==>
   {
      Graphics2D g2d = (Graphics2D)g;
      for (SumlShape s: this.shapes)
      {
         s.paint(g2d);
      }
   }//<==
}