// NightHunter Class
// NightHunter.java

/** Project 3, CIS 525
   Fall 2000
   By Terrence Burrows

   "Night Hunter" Java game.  The user can start a new game
   by typing in "n" or "N" and toggle the music on/off by
   typing "m" or "M".  This Java program is setup to run only
   as a "Java Applet" in a web browser and NOT as a standalone
   Java application.

   The framework for this program is by Michael Morrison
   from the book "Teach yourself Internet Game Programming
   with Java in 21 days". See chapters 6 through 12.
*/

// Imports
import java.awt.*;
import java.applet.*;
import java.util.Random;

/** This is the main class that is instantiated to begin
    the "Night Hunter" Java game.  This class handles high-level
    animation, game timing loop, sound issues, and user
    input. */
public class NightHunter extends Applet implements Runnable {
  private Image         offImage, back, gunImage;
  private AudioClip     music, gunsound, applause;
  private AudioClip[]   clip = new AudioClip[5];
  private Graphics      offGrfx;
  private Thread        animate;
  private MediaTracker  tracker;
  private SRVector      srv;          // Game Background
  /** Mouse/Gun image */
  private Sprite        gun;
  /** Animation frame rate = 12 FPS */
  private int           delay = 83;
  private Font          infoFont = new Font("Helvetica",Font.PLAIN, 14);
  private FontMetrics   infoMetrics;
  private Random        rand = new Random(System.currentTimeMillis());
  private boolean       musicOn = true;
  private static int    level, killed;
  public static int     lost;

  public String getAppletInfo() {
    return (new String("Night Hunter by Terrence Burrows"));
  }

  /** Game initialization method - starts the MediaTracker (needed
    to make sure images are completely loaded), load game
    background the mouse - gun images, and load audio clips. */
  public void init() {
    /** Load and track the images with the MediaTracker */
    tracker = new MediaTracker(this);
    back = getImage(getCodeBase(), "Res/Back2.gif");
    tracker.addImage(back, 0);
    gunImage = getImage(getCodeBase(), "Res/Gun.gif");
    tracker.addImage(gunImage, 0);
    Eyes.initResources(this, tracker, 0);

    // Load the audio clips
    music = getAudioClip(getCodeBase(), "Res/Music.au");
    applause = getAudioClip(getCodeBase(), "Res/Applause.au");
    gunsound = getAudioClip(getCodeBase(), "Res/Biggun.au");
    clip[0] = getAudioClip(getCodeBase(), "Res/Crow.au");
    clip[1] = getAudioClip(getCodeBase(), "Res/Hyena.au");
    clip[2] = getAudioClip(getCodeBase(), "Res/Monkey.au");
    clip[3] = getAudioClip(getCodeBase(), "Res/Tiger.au");
    clip[4] = getAudioClip(getCodeBase(), "Res/Wolf.au");
  }

  /** Standard thread start handler method */
  public void start() {
    if (animate == null) {
      animate = new Thread(this);
      animate.start();
    }
  }

  /** Standard thread termination handler method - *** added
      call to stop music when thread terminates */
  public void stop() {
    if (animate != null) {
      animate.stop();
      animate = null;
    }
    music.stop();   //make sure to terminate music
  }

  /** When an object is derived from a "Runnable" class then this
      method is called right after the thread "start()" method
      completes.  *** This method is the heart of the game because
      this is where a new game is set up and this is where the
      game timing loop is implemented.  */
  public void run() {
    try {
      tracker.waitForID(0);
    }
    catch (InterruptedException e) {
      return;
    }

    // Setup a new game
    newGame();

    long t = System.currentTimeMillis();  //get current time

    // While the thread is active update() and repaint() everything
    // every "delay" milliseconds.
    while (Thread.currentThread() == animate) {
      srv.update();
      repaint();
      try {
        t += delay;
        Thread.sleep(Math.max(0, t - System.currentTimeMillis()));
      }
      catch (InterruptedException e) {
        break;
      }
    }
  }

  /** This image update method uses "double-buffering" for bitmap
      images to eliminate screen flicker. Draw the screen image
      as well as game info (level etc.).  If game is over display
      "Game Over" message and stop music.  *** This is where new
      creatures get added randomly depending on game level. */
  public void update(Graphics g) {
    // Create the offscreen graphics context
    if (offGrfx == null) {
      offImage = createImage(size().width, size().height);
      offGrfx = offImage.getGraphics();
      infoMetrics = offGrfx.getFontMetrics(infoFont);
    }

    // Draw the sprites - includes the background as well
    // bitmap images
    srv.draw(offGrfx);

    // Draw the game info
    offGrfx.setFont(infoFont);
    offGrfx.setColor(Color.white);
    offGrfx.drawString(new String("Level: " + level +
      "  Killed: " + killed + "  Got Away: " + lost), 10, 5 +
      infoMetrics.getAscent());

    // Is the game over?
    if (lost >= 5) {
      Font        f = new Font("Helvetica", Font.BOLD, 36);
      FontMetrics fm = offGrfx.getFontMetrics(f);
      String      s = new String("Game Over");
      offGrfx.setFont(f);
      offGrfx.drawString(s, (size().width - fm.stringWidth(s)) / 2,
        ((size().height - fm.getHeight()) / 2) + fm.getAscent());

      // Stop the music
      music.stop();
    }
    else
      // Add a new creature?
      if ((rand.nextInt() % (20 - level / 2)) == 0)
        srv.add(new Eyes(this, 1 - Math.abs(rand.nextInt() % 2),
        level, Math.abs(rand.nextInt() % 200)));

    // Draw the image onto the screen
    g.drawImage(offImage, 0, 0, null);
  }

  /** Paint method that uses the Media Tracker to insure images
      are loaded.  If images are not completely loaded then
      a message will be displayed to the user until the image is
      loaded. */
  public void paint(Graphics g) {
    if ((tracker.statusID(0, true) & MediaTracker.ERRORED) != 0) {
      // Draw the error rectangle
      g.setColor(Color.red);
      g.fillRect(0, 0, size().width, size().height);
      return;
    }
    //check if images are loaded
    if ((tracker.statusID(0, true) & MediaTracker.COMPLETE) != 0) {
      // Image loaded - Draw the offscreen image
      g.drawImage(offImage, 0, 0, null);
    }
    else {
      // Image not loaded - Draw the title message
      // until the images load)
      Font        f1 = new Font("TimesRoman", Font.BOLD, 28),
                  f2 = new Font("Helvetica", Font.PLAIN, 16);
      FontMetrics fm1 = g.getFontMetrics(f1),
                  fm2 = g.getFontMetrics(f2);
      String      s1 = new String("Night Hunter"),
                  s2 = new String("Loading images...");
      g.setFont(f1);
      g.drawString(s1, (size().width - fm1.stringWidth(s1)) / 2,
        ((size().height - fm1.getHeight()) / 2) + fm1.getAscent());
      g.setFont(f2);
      g.drawString(s2, (size().width - fm2.stringWidth(s2)) / 2,
        size().height - fm2.getHeight() - fm2.getAscent());
    }
  }

  /** Mouse Enter Event - when mouse enters game frame
      show gun crosshairs. */
  public boolean mouseEnter(Event evt, int x, int y) {
    if (gun != null)
      gun.show();
    return true;
  }

  /** Mouse Exit Event - when mouse exits game frame
      hide gun crosshairs. */
  public boolean mouseExit(Event evt, int x, int y) {
    if (gun != null)
      gun.hide();
    return true;
  }

  /** Mouse Move Event - update gun crosshair position. */
  public boolean mouseMove(Event evt, int x, int y) {
    if (gun != null)
      gun.setPosition(new Point(x - 10, y - 10));
    return true;
  }

  /** Mouse Down Event - check if mouse/gun is over
      sprite, if it is kill sprite.  Play gun sound
      and sprite death sound if hit. */
  public boolean mouseDown(Event evt, int x, int y) {
    if (lost < 5) {
      //Sprite s = srv.isPointInside(new Point(x - 5, y - 5));
      Sprite s = srv.isPointInside(new Point(x , y ));
      if (s != null) {
        // Remove the creature and increase number killed
        srv.removeElement(s);
        if ((++killed % 15) == 0) {
          // Increase the level and play applause sound
          level++;
          applause.play();
        }
        else
          // Play the gun sound and creature hit sound
          gunsound.play();
          //select random creature sound
          clip[Math.abs(rand.nextInt() % 5)].play();
      }
      else
        // Play the gun sound
        gunsound.play();
    }
    return true;
  }

  /** Keyboard keyDown Event - check for user input
      for new game or toggle music on/off. */
  public boolean keyDown(Event evt, int key) {
    if ((key == (int)'n') || (key == (int)'N'))
      newGame();
    else if ((key == (int)'m') || (key == (int)'M')) {
      musicOn = !musicOn;
      if (musicOn)
        music.loop();
      else
        music.stop();
    }
    return true;
  }

  /** Setup a new game. */
  void newGame() {

    level = 1;
    killed = lost = 0;
    srv = new SRVector(new ImageBackground(this, back));
    gun = new Sprite(this, gunImage, new Point((size().width -
      gunImage.getWidth(this)) / 2, (size().height -
      gunImage.getHeight(this)) / 2), new Point(0, 0), 20,
      Sprite.BA_WRAP);
    srv.add(gun);
    if (musicOn)
      music.loop();   // Command music to loop repeatidly
  }
}