/*  
 *   Tetris by Eric Idema - idemaeri@cps.msu.edu 
 *
 *   	   This code is for educational purposes only.  
 */


import java.awt.*;
import java.applet.*;
import Shape;

public class Tetris extends Applet implements Runnable {

  Color[][] alley;  

  Shape shape, nextShape;

  Thread engine;

  Image buffer, alley_buffer,  //used in double buffering
        bground, title;        //snazzy background and title

  MediaTracker tracker;  

  boolean gameStarted,
          gameOver,
          update_alley = true; //used in double buffering

  int level = 0,
      points = 0,
      lines = 0;

  public void init() {
    gameStarted = false;
    gameOver = false;

    tracker = new MediaTracker( this );  //get the images
    bground = getImage( getCodeBase(), "bground.gif" );
    title   = getImage( getCodeBase(), "title.gif"   );
    tracker.addImage( bground, 0 );
    tracker.addImage( title, 0 );
    
    buffer = createImage( 250, 300 );  //create buffer images
    alley_buffer = createImage( 250, 300 );
    alley = new Color[10][20];
    engine = new Thread( this );

      //wait for all the images to load in before starting 
    try{ tracker.waitForAll(); } catch( Exception e ) {}
  }

  public void gameStart() {
    gameOver = false;
    for( int i = 0; i < 10; i++ ) {   //set the alley to Color.white
      for( int j = 0; j < 20; j++ ) { //this never gets painted, but
        alley[i][j] = Color.white;    //is used to signal and unoccupied
      }
    }
    update_alley = true;
    shape = new Shape();
    nextShape = new Shape();
    repaint();
    if( !gameStarted ) {
      gameStarted = true;
      engine.start();
    }
    else
      engine.resume();
  }

  public void stop() {
    engine.suspend();
  }

  public boolean mouseDown( Event evt, int x, int y ) {
    if( !gameStarted || gameOver ) {
      points = lines = level = 0;
      gameStart();
      return true;
    }
    return false;
  }

  public boolean keyDown( Event evt, int keyCode ) {
    if( gameOver ) return true;

    if( keyCode == Event.LEFT || keyCode == 'j' ) {
      shape.moveLeft( alley );
      repaint();
      return true;
    }
    if( keyCode == Event.RIGHT || keyCode == 'l' ) {
      shape.moveRight( alley );
      repaint();  
      return true;
    }
    if( keyCode == Event.DOWN || keyCode == 'k' ) {
      while( !shape.isFrozen( alley ) )
        shape.drop();
      shape.frozen( alley );
      checkForLine();
      points += 5;
      update_alley = true;
      shape = nextShape;
      nextShape = new Shape();
      repaint();
      return true;
    }
    else if( keyCode == Event.UP || keyCode == 'i' ) {
      shape.rotate( alley );
      repaint();
      return true;
    }
    return false;
  }

  public void update( Graphics g ) {
    Graphics backgraphics = buffer.getGraphics();
    Graphics alleygraphics = alley_buffer.getGraphics();
    if( update_alley ) {
      paint_alley( alleygraphics );
      update_alley = false;
    }
    paint( backgraphics );
    g.drawImage( buffer, 0, 0, this );
  }
  
  public void paint_alley( Graphics g ) {
    g.drawImage( bground, 0, 0, this );
    for( int i = 0; i < 10; i++ ) {
      for( int j = 0; j < 20; j++ ) {
        if( alley[i][j] != Color.white ) {
          g.setColor( alley[i][j] );
          g.fillRect( i*15, j*15, 15, 15 );
          g.setColor( Color.white );
          g.drawRect( i*15, j*15, 15, 15 );
          g.drawLine( i*15, j*15, i*15+15, j*15+15 );
          g.drawLine( i*15+15, j*15, i*15, j*15+15 );
        }
      }
    }
  }

  public void paint( Graphics g ) {
    if( !gameStarted ) {
      g.drawImage( title, 0, 0, this );
      return;
    }
    if( gameOver ) {
      g.drawImage( bground, 0, 0, this );
      g.setColor( Color.red );
      g.drawString( "Game Over", 40, 150 );
//      g.drawString( "Click Here", 38, 160 );
      return;
    }
    g.drawImage( alley_buffer, 0, 0, this );
    shape.paint( g );
    g.setColor( Color.white );
    g.fillRect( 150, 0, 100, 300 );
    g.setColor( Color.black );
    g.drawLine( 150, 0, 150, 300 );
  //  g.drawLine( 0, 0, 150, 0 );
    nextShape.paintNext( g );
    g.setColor( Color.black );
    g.drawString( "Level: " + level, 155, 90 );
    g.drawString( "Lines: " + lines, 155, 110 );
    g.drawString( "Points: " + points, 155, 130 );
  }

  public void run() {
    if( shape.isFrozen( alley ) ) {
      shape.frozen( alley );
      points += 5;
      checkForLine();
      shape = nextShape;
      nextShape = new Shape();
      update_alley = true;
      if( gameOver = shape.checkGameOver( alley ) ) {
        repaint();
        stop();
      }
    }
    else {
      shape.drop();
    }
    repaint();
    try {
    engine.sleep( 500 - 30*level );
    } catch( Exception e ) {}
    run();
  }

  public void checkForLine() {
    boolean remove; 
    int lines_removed = 0;
    for( int j = 0; j < 20; j++ ) {
      remove = true;
      for( int i = 0; i < 10 && remove; i++ ) {
        if( alley[i][j] == Color.white )
          remove = false;
      }
      if( remove ) {
        for( int i = j; i > 0; i-- ) {
          for( int p = 0; p < 10; p++ ) {
            alley[p][i] = alley[p][i-1];
          }
        }
        lines_removed++;
      }
    }
    lines += lines_removed;
    switch( lines_removed ) {
      case 1:  
        points += 100;
      break;
      case 2:
        points += 300;
      break;
      case 3:
        points += 800;
      break;
      case 4:
        points += 1500;
      break;
    }     
    level = lines / 10;
  }

}