/* 
 * TicTacToe.java
 * An implementation of the Tic Tac Toe game.
 * To compile: javac -classpath twoplayer.jar:. TicTacToe.java
 * To run CLUI: java -classpath twoplayer.jar:. TicTacToe
 */

public class TicTacToe extends TwoPlayerGame implements CLUIPlayableGame, GUIPlayableGame {   
    public static final String BLANK = " ";
    public final int DRAW = 0;
    private String one = BLANK, two = BLANK, three = BLANK, four = BLANK, five = BLANK, six = BLANK,
	seven = BLANK, eight = BLANK, nine = BLANK;
    private int winner;

    public TicTacToe() { 
    }
    public String getRules() {
        return "\n*** The Rules of Tic Tac Toe ***\n" +
	    "                 1 2 3\n" +
	    "                 4 5 6\n" +
	    "                 7 8 9\n" +
	    "Player 1 is X and player 2 is O\n";
    }
    public String getSquare(int n) {
        switch (n) {
	case 1: return one;
	case 2: return two;
	case 3: return three;
	case 4: return four;
	case 5: return five;
	case 6: return six;
	case 7: return seven;
	case 8: return eight;
	case 9: return nine;
	}
	return "";
    }
    public String getWinner() {
        if (winner == 0)
	    return "It's a draw!\n";
        return "Player " + winner + " is the winner.\n";
    }
    public String reportGameState() {
        return  "\n" +
            one + " | " + two + " | " + three + "\n" +
            "----------\n" +
	    four + " | " + five + " | " + six + "\n" +
            "----------\n" +
	    seven + " | " + eight + " | " + nine + "\n";
    }
    public String getGamePrompt() {
        return "\nPlayer " + getPlayer() + ": Type in an empty square, 1 to 9 :  ";
    }
    public String submitUserMove(String theMove) {
        int square = Integer.parseInt(theMove);
        String mark="";
        if (getPlayer()==PLAYER_ONE)
            mark = "X";
	else
	    mark = "O";
        if (makeLegalMove(square,mark)) {
            changePlayer();
            if (gameOver()) {
                return reportGameState() + "\nGame over! " + getWinner() + "\n";
	    } else {
                return reportGameState() + getGamePrompt();
	    }
	}
        return "\nOops. " + square + " is an illegal move." + getGamePrompt();
    }
    public boolean gameOver() {
        return xWins() || oWins() || itsADraw();
    }
    private boolean itsADraw() {
        for (int k = 0; k<= 9; k++) 
            if (getSquare(k).equals(BLANK))
		return false;
	winner = DRAW;
	return true;
    }
    private boolean xWins() {
        if (one.equals("X") && one.equals(two) && two.equals(three) ||
	    four.equals("X") && four.equals(five) && five.equals(six) ||
	    seven.equals("X") && seven.equals(eight) && eight.equals(nine) ||
	    one.equals("X") && one.equals(five) && five.equals(nine) ||
            one.equals("X") && one.equals(four) && four.equals(seven) ||
	    two.equals("X") && two.equals(five) && five.equals(eight) ||
	    three.equals("X") && three.equals(six) && six.equals(nine) ||
	    three.equals("X") && three.equals(five) && five.equals(seven)) {
	    winner = PLAYER_ONE;
	    return true;
	}
	return false;
    }
    private boolean oWins() {
        if (one.equals("O") && one.equals(two) && two.equals(three) ||
	    four.equals("O") && four.equals(five) && five.equals(six) ||
	    seven.equals("O") && seven.equals(eight) && eight.equals(nine) ||
	    one.equals("O") && one.equals(five) && five.equals(nine) ||
            one.equals("O") && one.equals(four) && four.equals(seven) ||
	    two.equals("O") && two.equals(five) && five.equals(eight) ||
	    three.equals("O") && three.equals(six) && six.equals(nine) ||
	    three.equals("O") && three.equals(five) && five.equals(seven)) {
	    winner = PLAYER_TWO;
	    return true;
	}
	return false;
    }

    public void play(UserInterface ui) {
        if (nComputers == 0) {
            ui.report("At least 1 player must be a computer.\n");
            return;
	}
        ui.report(getRules());

        if (nComputers == 1) {
            ui.report("You are player 1 and I am player 2, a " + computer2.toString() + "\n");
	} else if (nComputers == 2) {
            ui.report("Player 1 is a " + computer1.toString() + 
                       "\nand player 2 is a " +  computer2.toString() + "\n");
	}
	while(!gameOver()) {  
           IPlayer computer = null;       // Assume no computers playing
	    ui.report(reportGameState());
            switch(getPlayer()) {
	    case PLAYER_ONE:             // Player 1's turn
		computer = computer1;
		break;
	    case PLAYER_TWO:             // Player 2's turn
		computer = computer2;
		break;
	    } // cases

            if (computer != null) {      // If computer's turn
		ui.report(submitUserMove(computer.makeAMove("")));
	    } else {                     // otherwise, user's turn
		ui.prompt(getGamePrompt());
                ui.report(submitUserMove(ui.getUserInput()));
	    }
        } // while
	ui.report(reportGameState());  // The game is now over
    }

    public boolean makeLegalMove(int m, String s) {
	switch(m) {
        case 1: if (one.equals(BLANK)) {one = s; return true; } break;
        case 2: if (two.equals(BLANK)) {two = s; return true;}; break;
        case 3: if (three.equals(BLANK)) {three = s; return true; } break;
        case 4: if (four.equals(BLANK)) {four = s; return true; } break;
        case 5: if (five.equals(BLANK)) {five = s; return true; } break;
        case 6: if (six.equals(BLANK)) {six = s; return true; } break;
        case 7: if (seven.equals(BLANK)) {seven = s; return true; } break;
        case 8: if (eight.equals(BLANK)) {eight = s; return true; } break;
        case 9: if (nine.equals(BLANK)) { nine = s; return true; } break;
	}
        return false;
    }

    public static void main(String args[]) {
        KeyboardReader kb = new KeyboardReader();
        TicTacToe game = new TicTacToe();
        kb.prompt("How many computers are playing, 1 or 2? ");
	int m = kb.getKeyboardInteger();
        for (int k = 0; k < m; k++) {
            IPlayer computer = new TicTacToePlayer(game);
            game.addComputerPlayer(computer);
	}
        game.play(kb);
    }

}