import java.awt.*;

class ExCanvas extends Panel {
  BorderLayout l = null;
  Dimension min_size = new Dimension(100, 100);
  Dimension pref_size = new Dimension(100, 100);
  Graphics g2;
  Image image=null, org=null, pnt=null, pnt_hi=null, buffy=null;
  int org_width=0, org_height=0, pnt_width=0, pnt_height=0;
  int org_x=0, org_y=0;
  Scrollbar vertical;
  Scrollbar horizontal;
  boolean origin_select=true;
  boolean point_select=false;
  boolean inside = false;
  int last_x = 0, last_y = 0;
  Triplet points = null;
  model3D creator = null;
  
  public ExCanvas(Image picture, Image origin, Image point, Image highlight, model3D c) {
    creator = c;
    l = new BorderLayout();
    setLayout(l);
    image = picture;
    buffy = c.createImage(picture.getWidth(this), picture.getHeight(this));
    g2 = buffy.getGraphics();
    org = origin;
    org_width = org.getWidth(this);
    org_height = org.getHeight(this);
    pnt = point;
    pnt_width = pnt.getWidth(this);
    pnt_height = pnt.getHeight(this);
    pnt_hi = highlight;
    min_size = new Dimension(Math.min(min_size.width, picture.getWidth(this)),
			     Math.min(min_size.height, picture.getHeight(this)));
    pref_size = new Dimension(picture.getWidth(this)+15, picture.getHeight(this)+15);
    vertical = new Scrollbar(Scrollbar.VERTICAL);
    vertical.setValues(0, 1, 0, 0);
    horizontal = new Scrollbar(Scrollbar.HORIZONTAL);
    horizontal.setValues(0, 1, 0, 0);
    add("East", vertical);    
    add("South", horizontal);
    layout();
  }


  public void update(Graphics g) {
    paint(g);
  }

  public void paint(Graphics g) {
    simple_paint(g2);
    g.drawImage(buffy, 0, 0, this);
  }
  
  
  public void simple_paint(Graphics g) {
    if (image!=null) {
      g.drawImage(image, 0, 0, this);
    }
    if (!origin_select) {
      if (org!=null) {
	g.drawImage(org, org_x, org_y, this);
      }
    }
    if (pnt!=null) {
      Triplet tmp = points;
      while (tmp!=null) {
	Point p = (Point) tmp.first;
	g.drawImage(pnt, p.x, p.y, this);
	tmp = (Triplet) tmp.second;
      }
    }
    if (inside) {
      if (origin_select) {
	if (org!=null) {
	  g.drawImage(org, last_x, last_y, this);
	}
      }
      else {
	if (pnt_hi!=null) {
	  g.drawImage(pnt_hi, last_x, last_y, this);
	}
      }
    }
    vertical.paint(g);
    horizontal.paint(g);
  }

  public Dimension preferredSize() {
    return pref_size;
  }
  
  public Dimension minimumSize() {
    return min_size;
  }
  
  public void layout() {
    Dimension d = size();
    vertical.reshape(d.width-15 ,0 , 15, d.height-15);
    horizontal.reshape(0, d.height-15, d.width-15, 15);
  }

  public boolean mouseEnter(Event e, int mx, int my) {
    if (origin_select) {
      last_x = mx-org_width;
      last_y = my-org_height;
    }
    else {
      last_x = mx-pnt_width;
      last_y = my-pnt_height;
    }
    inside = true;
    repaint();
    return true;
  }

  public boolean mouseMove(Event e, int mx, int my) {
    if (origin_select) {
      last_x = mx-org_width;
      last_y = my-org_height;
    }
    else {
      last_x = mx-pnt_width;
      last_y = my-pnt_height;
    }
    repaint();
    return true;
  }

  public void getPoints() {
    point_select=true;
  }

  public boolean mouseDown(Event e, int mx, int my) {
    if (origin_select) {
      org_x = mx-org_width;
      org_y = my-org_height;
      origin_select=false;
      creator.deliver_point(this, mx, my);
    }
    else if (point_select) {
      points = new Triplet(new Point(mx-pnt_width,my-pnt_height),points,null);
      point_select=false;
      creator.deliver_point(this, mx, my);
    }
    repaint();
    return true;
  }

  public boolean mouseExit(Event e, int mx, int my) {
    inside = false;
    repaint();
    return true;
  }

}