import java.applet.*;
import java.*;
import java.awt.*;
import java.util.*;
import java.lang.*;

public class Homerun extends Applet {

  TrajectoryPoint[] history;
  Image img = null;
  Image imgback = null;
  Image back, ball;
  Image[] batter;
  boolean erase = true;
  int batterindex = -1;
  boolean newball;
  int xball, yball;
  Graphics gi = null;
  Graphics g2;
  BB bb;
  boolean okToHit;
  Choice alt;
  Scrollbar vel, ang; 
  String[] cities = {"New York", "St. Louis","Milwaukee","Kansas City","Atlanta","Denver","Pike's Peak"};
  int[] elevations = {55, 470, 593, 800, 1050, 5280, 14109};

  Button hit, clearButt;
  double initialAltitude, initialVelocity, initialAngle;
  Font fhelp, distFont;

  Label altLab, velLab, angLab;
  final double M2FT = 3.28084;
  final double MPS2MPH = 2.23694;
  int distance = -1;

  boolean showHelp = true;

  AudioClip batSound, fanSound;
  
  public void init() {
    GetMediaFile gif = new GetMediaFile(this);
    batSound = gif.getAudioClip("woodbat.au");
    fanSound = gif.getAudioClip("fans.au");
    back = gif.getImage("ballpark.gif");
    ball = gif.getImage("ball.gif");
    batter = new Image[3];
    batter[0] = gif.getImage("batter0.gif");
    batter[1] = gif.getImage("batter1.gif");
    batter[2] = gif.getImage("batter2.gif");
    batterindex = 0;
    newball = false;
    okToHit = true;
    bb = new BB();
    distFont = new Font("sansserif",Font.BOLD,18);
    fhelp = new Font("sans",Font.PLAIN,14);

    setLayout(null);
    Color bc = new Color(1, 153, 1);
    setBackground(bc);

    initialAltitude = 1609.;
    initialAngle = 40.;
    initialVelocity = 40.;
    hit = new Button("Hit");
    clearButt = new Button("Clear");

    alt = new Choice();
    alt.setForeground(Color.black);
    String cityparam = getParameter("cities");
    String eleparam = getParameter("elevations");
    if (cityparam != null && eleparam != null) {
      StringTokenizer stc = new StringTokenizer(cityparam,",");
      StringTokenizer ste = new StringTokenizer(eleparam,",");
      int n = stc.countTokens();
      cities = new String[n];
      elevations = new int[n];
      for (int i=0; i<n; i++) {
        cities[i] = stc.nextToken().trim();
        elevations[i] = Integer.parseInt(ste.nextToken().trim());
      }
    }

    for (int i=0; i< cities.length; i++) {
      alt.addItem(cities[i]);
    }
    alt.select(0);
    Font falt = new Font("sans",Font.PLAIN,18);
    alt.setFont(falt);

    vel = new Scrollbar(Scrollbar.HORIZONTAL,60, 15, 1, 155);
    ang = new Scrollbar(Scrollbar.HORIZONTAL,30, 10, 0, 100);

    altLab = new Label("Elevation = "+elevations[alt.getSelectedIndex()], Label.CENTER);
    velLab = new Label("Speed = "+vel.getValue(), Label.CENTER);
    angLab = new Label("Angle = "+ang.getValue(), Label.CENTER);

    Font fnt = new Font("sans",Font.BOLD,16);

    altLab.setFont(fnt);
    alt.setBounds(10, 500, 150, 30);
    altLab.setBounds(10,540,150,30);
    add(alt);
    add(altLab);

    vel.setBounds(200, 500, 170, 30);
    velLab.setFont(fnt);
    velLab.setBounds(200, 540, 170, 30);
    add(vel);
    add(velLab);

    ang.setBounds(410, 500, 170, 30);
    angLab.setFont(fnt);
    angLab.setBounds(410, 540, 170, 30);
    add(ang);
    add(angLab);

    hit.setFont(fnt);
    hit.setBounds(630, 490, 60, 50);
    clearButt.setFont(fnt);
    clearButt.setBounds(720, 490, 60, 50);
    add(hit);
    add(clearButt);

    showHelp = true;


    show();
    repaint();
  }

  public boolean handleEvent(Event e) {

    if (e.target == vel) {
      velLab.setText("Speed = "+vel.getValue());
      okToHit = true;
      hit.enable(true);
      return true;
    }

    if (e.target == ang) {
      angLab.setText("Angle = "+ang.getValue());
      okToHit = true;
      hit.enable(true);
      return true;
    }
    return super.handleEvent(e);
  }


  public boolean action(Event e, Object o) {

    if (e.target == alt) {
      altLab.setText("Altitude = "+elevations[alt.getSelectedIndex()]);
      okToHit = true;
      hit.enable(true);
      return true;
    }

    if (e.target == hit && okToHit) {
      // make the batter go...

      okToHit = false;
      hit.enable(false);
      batSound.play();
      distance = -1;

      for (int i=1; i<3; i++) {
        batterindex = i;
        paint(this.getGraphics());
        try {
          Thread.sleep(200);
        } catch (Exception eb) {;}
      }

      initialAltitude = elevations[alt.getSelectedIndex()] / M2FT;
      initialVelocity = vel.getValue() / MPS2MPH;
      initialAngle = (double) ang.getValue();

      //System.out.println("initial vel = "+initialVelocity);
      history = bb.Trajectory(initialAltitude, 
                        initialVelocity, initialAngle, .1, true, 1000);

      boolean cheer = false;
      for (int i=2; i<bb.npts; i++) {
      //  System.out.println("m, ft = "+history[i].position[0]+" "+history[i].position[0] * M2FT);

        xball = 40 + (int)Math.round(1.8*325. * history[i].position[0]*M2FT/400.);
        yball = 310 - (int)Math.round(1.8*150. * history[i].position[1]*M2FT/200.);
        newball = true;
        if (!cheer && xball > 623) {   // 1.8 * 345.
          cheer = true;
          fanSound.play();
        }
        paint(this.getGraphics());
        try {
          Thread.sleep(60);
        } catch (Exception eb) {;}
      }

      distance = (int)Math.round(history[bb.npts-1].position[0]*M2FT);
      batterindex = 0;
      paint(this.getGraphics());
      return true;
    }

    if (e.target == clearButt) {
      if (img != null) {
        img.flush();
        imgback.flush();
      }
      img = null;
      imgback = null;
      distance = -1;
      paint(this.getGraphics());
      okToHit = true;
      hit.enable(true);
      return true;
    }

    return false;
  }

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

  public void paint(Graphics g) {

    if (img == null) {
      img = createImage(back.getWidth(this), back.getHeight(this));
      gi = img.getGraphics();
      gi.drawImage(back,0,0,this);
      imgback = createImage(back.getWidth(this), back.getHeight(this));
    }

    gi = img.getGraphics();

    if (newball) {
      gi.drawImage(ball,xball,yball,this);
    }
    newball = false;

    g2 = imgback.getGraphics();
    g2.drawImage(img,0,0,this);

    if (batterindex >= 0) {
      int xoff = 30;
      if (batterindex == 2) xoff = 18;
      g2.drawImage(batter[batterindex],xoff,285,this);
      if (distance > 0) {
        g2.setFont(distFont);
        g2.setColor(Color.black);
        g2.drawString(distance+" feet",600, 455);
        g2.setColor(Color.white);
        g2.drawString(distance+" feet",601, 456);
      }
    }

    if (showHelp) {
      g2.setColor(Color.white);
      g2.setFont(fhelp);
      g2.drawString("Pick a city (elevation)",20,490);
      g2.drawString("Set speed of hit ball",225,490);
      g2.drawString("Set angle leaving bat",430,490);
    }

    g.drawImage(imgback,0,0,this);
    g2.dispose();
    gi.dispose();
    g.dispose();
  }

  /**
  * @param t temperature (K)
  * @param td dewpoint (K)
  *
  */
  public double makeRhoZero(double t, double td) {
    return (.348388 * 1013.2 / virtualTemperature(t, td, 1013.2));
  }

  /** Virtual Temperature
  *
  */
  public double virtualTemperature(double t, double td, double p) {
    return ( t * (1.0 + .000609*mixingRatio(td, p)) );
  }

  /** saturation vapor pressure over water.  t in kelvin.
  *
  */
  public double satVapPres(double t) {
    double coef[]={6.1104546,0.4442351,1.4302099e-2, 2.6454708e-4,
              3.0357098e-6, 2.0972268e-8, 6.0487594e-11,-1.469687e-13};

    // sat vap pressures every 5C from -50 to -200
    double escold[] = {
      0.648554685769663908E-01, 0.378319512256073479E-01,
      0.222444934288790197E-01, 0.131828928424683120E-01,
      0.787402077141244848E-02, 0.473973049488473318E-02,
      0.287512035504357928E-02, 0.175743037675810294E-02,
      0.108241739518850975E-02, 0.671708939185605941E-03,
      0.419964702632039404E-03, 0.264524363863469876E-03,
      0.167847963736813220E-03, 0.107285397631620379E-03,
      0.690742634496135612E-04, 0.447940489768084267E-04,
      0.292570419563937303E-04, 0.192452912634994161E-04,
      0.127491372410747951E-04, 0.850507010275505138E-05,
      0.571340025334971129E-05, 0.386465029673876238E-05,
      0.263210971965005286E-05, 0.180491072930570428E-05,
      0.124607850555816049E-05, 0.866070571346870824E-06,
      0.605982217668895538E-06, 0.426821197943242768E-06,
      0.302616508514379476E-06, 0.215963854234913987E-06,
      0.155128954578336869E-06};

    double temp = t - 273.16;
    double retval;

    if (temp > -50.) {

      retval = ( coef[0] + temp*(coef[1] + temp*(coef[2] + temp*(coef[3] +
      temp*(coef[4] + temp*(coef[5] + temp*(coef[6] + temp*coef[7])))))) );

    } else {
       double tt = (-temp - 50.)/5.;
       int inx = (int) tt;
       if (inx < escold.length) { 
         retval = escold[inx] + (tt % 1.)*(escold[inx+1]-escold[inx]);
       } else {
         retval = 1e-7;
       }

    }
    
    return retval;
  }

  /** mixing ratio
  *
  */
  public double mixingRatio(double t, double p) {
    double e = satVapPres(t);
    return ( 621.97*e/(p - e) );
  }


}