import vix.*;
import java.awt.*;
import java.awt.geom.*;
import java.awt.event.*;
import java.util.ArrayList;

public class FiltroZoom extends Filter
{
  protected static final float FATOR_AFASTAMENTO = 0.8F;
  protected static final Color COR_XOR = Color.white;
  protected static final Cursor CURSOR = new Cursor(Cursor.CROSSHAIR_CURSOR);

  protected Point2D p1, p2;
  protected boolean arrastando;
  protected boolean termina;
  protected Mapa mapa;

  public FiltroZoom(Mapa mapa) {
    this.mapa = mapa;
  }
  protected void inicia() {
    p1 = null;
    p2 = null;
    arrastando = false;
  }
  public boolean changeVS(TypeVS old_vs, TypeVS new_vs) {
    if (super.changeVS(old_vs, new_vs)) {
      if (vs != null) {
        PegaMapaMsg pega_mapa = new PegaMapaMsg();
        if (pega_mapa.sendVS(vs)) mapa.setCursor(CURSOR);
        inicia();
      }
      return true;
    }
    return false;
  }
  public void callbackKey(KeyEvent ev) {
    if (ev.getKeyCode() == ev.VK_ESCAPE) {
      if (arrastando) marca();
      mapa.insertFilter(null);
      return;
    }
    super.callbackKey(ev);
  }
  public void callbackButton(Point2D pt, MouseEvent ev) {
    if (ev.getID() == MouseEvent.MOUSE_PRESSED) {
      p1 = pt;
      return;
    }
    if (ev.getID() == MouseEvent.MOUSE_RELEASED) {
      if (p1!=null && arrastando) {
        p2 = pt;
        aproxima();
        p1 = null;
        p2 = null;
        arrastando = false;
      }
      else termina = true;
    }
    if (ev.getID() == MouseEvent.MOUSE_CLICKED) {
      if (termina) mapa.insertFilter(null);
    }
  }
  public void callbackDrag(Point2D pt, MouseEvent ev) {
    if (p1!=null && p2!=null) marca();
    p2 = pt;
    marca();
    arrastando = true;
  }
  protected void marca() {
    Graphics2D g = vs.getGraphics2D();
    float x = (float)Math.min(p1.getX(), p2.getX());
    float y = (float)Math.min(p1.getY(), p2.getY());
    float w = (float)Math.max(p1.getX(), p2.getX())-x+1;
    float h = (float)Math.max(p1.getY(), p2.getY())-y+1;
    Rectangle2D área = new Rectangle2D.Float(x, y, w, h);
    AffineTransform matriz = mapa.getMatriz();
    float espessura = (float)Math.min(1,1/matriz.getScaleX());
    g.setStroke(new BasicStroke(espessura));
    g.setXORMode(COR_XOR);
    g.draw(área);
  }
  protected void aproxima() {
    float x = (float)Math.min(p1.getX(), p2.getX());
    float y = (float)Math.min(p1.getY(), p2.getY());
    float w = (float)Math.max(p1.getX(), p2.getX())-x+1;
    float h = (float)Math.max(p1.getY(), p2.getY())-y+1;
    float apw = ((float)mapa.getWidth())/w;
    float aph = ((float)mapa.getHeight())/h;
    float escala = (apw<aph) ? apw : aph;
    mapa.setEscala(escala, new Point2D.Float(x+w/2, y+h/2));
  }
  public void afasta() {
    mapa.setEscala(mapa.getEscala()*FATOR_AFASTAMENTO);
  }
}