// Squares applet baseclass
// Draw two squares, then draw something interesting

import java.applet.*;
import java.awt.*;
import java.lang.Math;
import TransformableSquare;

public abstract class SquaresApplet extends DoubleBufferApplet {
  Graphics g;
  TransformableSquare square1, square2, activeSquare;
  int oldX, oldY;

  public boolean keyDown(Event e, int key) {
    if (e.x > 0 && e.y > 0) {			  // hack around NS/Win bug
      if (square1.inside(e.x, e.y))		  // doesn't set e.x,e.y
	activeSquare = square1;			  // on keyDown, bastards
      else if (square2.inside(e.x, e.y))
	activeSquare = square2;
      else
	return true;				  // nothing to do
    } else {
      // just let activeSquare be set as before..
    }
    switch (key) {
      case Event.LEFT:
      case 'j': activeSquare.rotate(2 * Math.PI * -9 / 360); break;
      case Event.RIGHT:
      case 'l': activeSquare.rotate(2 * Math.PI * 9 / 360); break;
      case Event.UP:
      case 'i': activeSquare.scale(1.1); break;
      case Event.DOWN:
      case 'k': activeSquare.scale(0.9); break;
    }
    redrawImage();
    return true;
  }

  public boolean mouseDown(Event e, int mouseX, int mouseY) {
    if (square1.inside(mouseX, mouseY))
      activeSquare = square1;
    else if (square2.inside(mouseX, mouseY))
      activeSquare = square2;
    else
      activeSquare = null;

    oldX = mouseX;
    oldY = mouseY;

    Graphics g = this.getGraphics();
    g.setXORMode(this.getBackground());
    if (activeSquare != null)
      g.drawPolygon(activeSquare.getPolygon());

    return true;
  }

  // move an XOR square around so the user can see what's going on
  public boolean mouseDrag(Event e, int mouseX, int mouseY) {
    Graphics g = this.getGraphics();
    g.setXORMode(this.getBackground());
    if (activeSquare != null && mouseX != oldX || mouseY != oldY) {
      g.drawPolygon(activeSquare.getPolygon());
      activeSquare.translate(mouseX - oldX, mouseY - oldY);
      g.drawPolygon(activeSquare.getPolygon());
      oldX = mouseX;
      oldY = mouseY;
    }
    return true;
  }
  
  public boolean mouseUp(Event e, int mouseX, int mouseY) {
    this.getGraphics().setPaintMode();

    if (activeSquare != null)
      activeSquare.translate(mouseX - oldX, mouseY - oldY);
    redrawImage();
    return true;
  }

  abstract public void redrawImage();
}