package fr.ove.openmath.jome.ctrlview.bidim;
   
   import java.awt.*;
   import java.awt.image.ImageObserver;
   import fr.ove.openmath.jome.ctrlview.bidim.*;
   import fr.ove.openmath.jome.ctrlview.bidim.images.ImageLoader;
   
   
   /***
  * The curly bracket.
  *
  * @author © 1999 DIRAT Laurent
  * @version 2.0 19/07/1999
  */
  public class CurlySymbol extends DisplayableImpl {
      /***
      * The initial images which are parts of the representation of the curly bracket.<BR>
      * The curly bracket is made of 4 parts : top, middle, bottom and bar.<BR>
      * The top, middle and bottom are unique during the rendering, and according to the height of the
      * bracketted display, mutiple instance of the bar are displayed to give the right size
      * to the curly bracket.
      */
      private Image topInit;
      private Image middleInit;
      private Image bottomInit;
      private Image barInit;
      
      /***
      * The scale images of the initials ones.
      */
      private Image top;
      private Image middle;
      private Image bottom;
      private Image bar;
      
      /***
      * The height of the top and the bottom of the symbol.
      */
      private int heightExtremities;
      
      /***
      * Object to be notified as more of the image is converted. 
      */
      ImageObserver observer;
       
      /***
      * The constructor.
      * @param isLeftBracket <CODE>true<CODE> if the instance represents a left bracket. <CODE>false</CODE>
      * otherwise.
      * @param heightExtremities the height of the extremities of the bracket.
      * @param observer the object to be notified as more of the image is converted.
      */
      public CurlySymbol(boolean isLeftBracket, int heightExtremities, ImageObserver observer) {
          if (isLeftBracket) {
              topInit = ImageLoader.getImage("LeftTopCurl");
              middleInit = ImageLoader.getImage("LeftMiddleCurl");
              bottomInit = ImageLoader.getImage("LeftBottomCurl");
              barInit = ImageLoader.getImage("LeftBarCurl");
          }
          else {
              topInit = ImageLoader.getImage("RightTopCurl");
              middleInit = ImageLoader.getImage("RightMiddleCurl");
              bottomInit = ImageLoader.getImage("RightBottomCurl");
              barInit = ImageLoader.getImage("RightBarCurl");
          }
  
          this.heightExtremities = heightExtremities;
          this.observer = observer;
      }
      
      /***
      * The paint method of the object to display.
      * @param g the drawing area of the symbol.
      */
      public void paint(Graphics g) {
          int height = getHeight();
          
          // On dessine la partie supÈrieure de l'accolade
          g.drawImage(top, 3, 0, observer);
          
          // On dessine les "barres", i.e. la partie que l'on va faire croitre pour ajuster correctement
          // la taille de l'accolade
          for (int i = heightExtremities; i < height - heightExtremities; i += heightExtremities)
              g.drawImage(bar, 3, i, observer);
          
          // On dessine la partie infÈrieure de l'accolade
          g.drawImage(bottom, 3, height - heightExtremities, observer);
          
          // On dessine la partie centrale de l'accolade
          // On essaie de faire en sorte que le milieu de l'accolade se trouve un peu au dessus de la baseline
          // Par exemple, alignÈ avec le +. La barre horizontale du + se trouve grosso modo ? la moitiÈ de
          // son ascent. Il se trouve que c'est la hauteur de middle.
          g.drawImage(middle, 3, getAscent() - middle.getHeight(observer), observer);
      }
      
      /***
      * Returns the preferred size of the display.
      */
      public Dimension getPreferredSize() {
 		MediaTracker tracker = new MediaTracker((Component) observer);
 		
 		// La hauteur de la partie du milieu est Ègale ? environ 2 fois les extrÈmitÈs.
 		
         // Le -1 signifie que la largeur sera proportionnelle ? la hauteur.
         top = topInit.getScaledInstance(-1, heightExtremities, Image.SCALE_SMOOTH);
         tracker.addImage(top, 0);
         middle = middleInit.getScaledInstance(-1, heightExtremities*2, Image.SCALE_SMOOTH);
         tracker.addImage(middle, 0);
         bottom = bottomInit.getScaledInstance(-1, heightExtremities, Image.SCALE_SMOOTH);
         tracker.addImage(bottom, 0);
         bar = barInit.getScaledInstance(-1, heightExtremities, Image.SCALE_SMOOTH);
         tracker.addImage(bar, 0);
         
         // On attend que toutes les images soient chargÈes.
 		try { tracker.waitForAll(); }
 		catch (InterruptedException e) {
 		    System.out.println(e.toString());
 		}
 		
         tracker.removeImage(top);
         tracker.removeImage(middle);
         tracker.removeImage(bottom);
         tracker.removeImage(bar);
 
         return new Dimension(top.getWidth(observer) + 6, getHeight());
     }
     
     /***
     * Sets the graphic context in which the object is.
     * @param graphicContext the object graphic context.
     * Actually, this methods gives information to the object, notably when its preferred
     * size is required. If the context has changed, the displayable object must be informed.
     * However, in the most part of the time, the whole graphic context won't be necessary to
     * be stored, but only specific and usefull data.
     */
     public void setGraphicContext(GraphicContext graphicContext) {
         super.setGraphicContext(graphicContext);
         // Surcharge de cette mÈthode pour que l'on puisse rÈcupÈrer en fonction du contexte graphique
         // du symbole, la hauteur des extrÈmitÈ de l'accolade.
         FontMetrics fm = Toolkit.getDefaultToolkit().getFontMetrics(graphicContext.getFont());
         heightExtremities = fm.getHeight() / 4;
     }
 }