import java.io.*;

/**
 * A basic implementation of the MineSweeper game, using a TextBoard for
 * display purposes and a StringTokenizer to parse commands entered at the
 * keyboard.  No support yet for anything fancy like high score tables (or
 * graphics :)  We do, however, time how long it takes you to finish the
 * game.
 */
public class MineSweeper {

  // The game board
  private Board board;

  // Tokenizer for commands
  private StreamTokenizer tok;

  // Various flags used by play() and doCommand()
  private boolean done, quit, win;

  // Contents of last cell revealed
  private int lastCell;


  /**
   * Create and initialise a new game of the given dimensions.
   */
  public MineSweeper(int width, int height, int mines) {
    // Create the game board
    board = new TextBoard(width, height, mines);

    // Set up the command tokenizer
    tok = new StreamTokenizer(new InputStreamReader(System.in));

    done = win = quit = false;
  }


  /**
   * Main game loop.
   */
  public void play() throws IOException {
    // Start the clock
    long startTime = System.currentTimeMillis();

    // Loop until game over, for whatever reason
    while (!done) {

      // Redraw board
      board.draw();

      // Get next command
      System.out.print("Command: ");
      System.out.flush();
      tok.nextToken();

      // Dispatch on command
      switch (tok.ttype) {
       case StreamTokenizer.TT_WORD:
	doCommand();
	break;
       case StreamTokenizer.TT_EOL:
	continue;
       case StreamTokenizer.TT_EOF:
	done = quit = true;
	break;
       default:
	System.out.println("Unknown command -- try 'help'");
      }

      // Check whether the game is up.  If the number of unknown cells = the
      // number of mines, you must have won (by finding all the mines).  If,
      // on the other hand, you revealed a mine, time to die :(
      if (board.getUnknown() == board.getMines()) {
	done = win = true;
      }
      else if (lastCell == Board.MINE) {
	done = true;
      }

      // Suck any remaining crap out of the input stream.  I'm not sure that
      // this works properly (not on my machine, at least).
      System.in.skip(System.in.available());
    }

    // Game over, one way or another.  Figure out how long it took
    long elapsedTime = System.currentTimeMillis() - startTime;

    // Reveal everything, just so the stats are correct
    for (int i = 0; i < board.getWidth(); i++) {
      for (int j = 0; j < board.getHeight(); j++) {
	board.reveal(i, j);
      }
    }

    // Redraw the board and print out some messages
    board.draw();
    if (win) {
      System.out.println("Congratulations -- you found all the mines!");
    }
    else if (!quit) {
      System.out.println("Bad luck -- you stepped on a mine!");
    }
    System.out.println("Total game time: "+(elapsedTime/1000)+" seconds");
  }


  /**
   * Process commands.  'Help' gives a summary of the huge range of available
   * commands.
   */
  private void doCommand() throws IOException {
    int x, y;

    if (tok.sval.equals("reveal")) {
      // Reveal a cell (and perhaps some around it)
      tok.nextToken();
      x = (int)tok.nval;
      tok.nextToken();
      y = (int)tok.nval;
      lastCell = board.reveal(x, y);
      if (lastCell == 0) {
	board.revealMore(x, y);
      }
    }
    else if (tok.sval.equals("mark")) {
      // Mark a cell
      tok.nextToken();
      x = (int)tok.nval;
      tok.nextToken();
      y = (int)tok.nval;
      board.mark(x, y);
    }
    else if (tok.sval.equals("unmark")) {
      // Unmark a cell
      tok.nextToken();
      x = (int)tok.nval;
      tok.nextToken();
      y = (int)tok.nval;
      board.unmark(x, y);
    }
    else if (tok.sval.equals("help")) {
      // Print some help
      System.out.println("reveal <x> <y>");
      System.out.println("mark <x> <y>");
      System.out.println("unmark <x> <y>");
      System.out.println("help");
      System.out.println("quit");
    }
    else if (tok.sval.equals("quit")) {
      // Quit and die
      quit = done = true;
    }
    else {
      System.out.println("Unknown command -- try 'help'");
    }
  }


  /**
   * Main program to start and run a new game.  Expects three command line
   * parameters: width, height and mine count.
   */
  public static void main(String[] args) throws IOException {

    MineSweeper game;

    if (args.length < 3) {
      System.out.println("Usage: java MineSweeper <width> <height> <mines>");
      System.exit(0);
    }
    else {
      int width = Integer.parseInt(args[0]);
      int height = Integer.parseInt(args[1]);
      int mines = Integer.parseInt(args[2]);
      game = new MineSweeper(width, height, mines);
      game.play();
    }
  }
}