6x7 Connect 4: Multiplayer and Singleplayer, with Special Moves

// This version has 2 special moves // 1. Invert: inverts the plays on the move // 2. Drill: clears the column the play is played into, including the play // All other rules of connect 4 are the same

import java.util.*;

public class Connect4 { public static Scanner in = new Scanner(System.in); public static int invertChance = 1; public static int drillChance = 1; public static boolean inverted = false;

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    // prints the rules of the game
    System.out.println("\n\n\t These are the Rules:\n" + 
                       "You can win on a Special Move\n" + 
                       "You will win if you get 4 in a row\n" +
                       "BEGIN!\n");

    String[][] board = {{" ", " ", " ", " ", " ", " ", " "}, 
                        {" ", " ", " ", " ", " ", " ", " "}, 
                        {" ", " ", " ", " ", " ", " ", " "}, 
                        {" ", " ", " ", " ", " ", " ", " "}, 
                        {" ", " ", " ", " ", " ", " ", " "}, 
                        {" ", " ", " ", " ", " ", " ", " "}, };
    // ask for the mode
    System.out.print("Multiplayer or Singleplayer? ");
    String choice = in.next().substring(0, 1);
    if(choice.equalsIgnoreCase("m")) {
        System.out.println("\n");
        multiplayer(board);
    }
    else if(choice.equalsIgnoreCase("s")) {
        System.out.print("As player 1 or player 2 (type the digit)? ");
        int choice2 = in.nextInt();        
        if(choice2 == 1) {
            System.out.println("\n");
            playerOne(board);
        }
        else if(choice2 == 2) {
            System.out.println("\n");
            playerTwo(board);
        }
        else
            System.out.println("Something went wrong.\nPlease reboot this programm.");
    } else {
        System.out.println("Something went wrong.\nPlease reboot this programm.");
    }
    in.close();
}

// checks if there is a winner
public static boolean checkForWinner(String[][] board) {
    String play = " ";
    boolean isWin = false;
    outerHorizontal:
    for(int a = 0; a < board.length; a++) {
        for(int b = 0; b < board[a].length - 3; b++) {
            play = board[a][b];
            if(play == " ")
                continue;
            if(board[a][b + 1] == play && board[a][b + 2] == play && board[a][b + 3] == play) {
                isWin = true;
                break outerHorizontal;
            }
                
        }
    }

    outerVertical:
    for(int x = 0; x < board.length - 3; x++) {
        for(int y = 0; y < board[x].length; y++) {
            play = board[x][y];
            if(play == " ")
                continue;
            if(board[x + 1][y] == play && board[x + 2][y] == play && board[x + 3][y] == play) {
                isWin = true;
                break outerVertical;
            }
        }
    }

    outerLeftDiagonal:
    for(int p = 0; p < board.length - 3; p++) {
        for(int o = 0; o < board[p].length - 3; o++) {
            play = board[p][o];
            if(play == " ")
                continue;
            if(board[p + 1][o + 1] == play && board[p + 2][o + 2] == play && board[p + 3][o + 3] == play) {
                isWin = true;
                break outerLeftDiagonal;
            }
        }
    }

    outerRightDiagonal:
    for(int u = 0; u < board.length - 3; u++) {
        for(int i = 3; i < board[u].length; i++) {
            play = board[u][i];
            if(play == " ")
                continue;
            if(board[u + 1][i - 1] == play && board[u + 2][i - 2] == play && board[u + 3][i - 3] == play) {
                isWin = true;
                break outerRightDiagonal;
            }
        }
    }

    return isWin;
}

// computer player
public static int AI(Random rand, String[][] board) {
    int play = rand.nextInt(7);
    while(board[0][play] != " ")
        play = rand.nextInt(7);
    return play + 1;
}

// prints out the board
public static void printBoard(String[][] board) {
    System.out.println("  $  1  $  2  $  3  $  4  $  5  $  6  $  7  $");
    for(int n = 0; n < board.length; n++) {
        for(int x = 0; x < board[n].length; x++) {
            System.out.print("  |  " + board[n][x]);
        }
        System.out.println("  |");
        if(n < board.length - 1)
            System.out.println("  +-----+-----+-----+-----+-----+-----+-----+");
        else
             System.out.println("  $  1  $  2  $  3  $  4  $  5  $  6  $  7  $");
    }
    // prints out the chance of a special move happening
    System.out.println("Chance of Invert Move: " + (invertChance * 2) + "%");
    System.out.println("Chance of Drill Move: " + drillChance + "%");

}

// updates the board to the next play
public static String[][] updateBoard(String[][] board, int play, int player) {
    play -= 1;
    Random rand = new Random();
    String spacing = "\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t";


    // sees if the next play is a Invert move
    boolean invert = false;
    if(rand.nextInt(50) < invertChance)
        invert = true;
    boolean notFinished = true;


    // sees if the next play is a Drill move
    boolean drill = false;
    if(rand.nextInt(100) < drillChance)
        drill = true;

    
    outer:
    // the actual play itself
    for(int n = board.length - 1; n >= 0; n--) {            
        if(board[n][play] == " ") {
            if(player == 1) {
                board[n][play] = "O";
                notFinished = false;
            } else {
                board[n][play] = "X";
                notFinished = false;
            }
        }
        // inverts all of the plays on the board
        if(invert) {
            System.out.println("\n" + spacing + "**********************\n" +
                               spacing + "INVERT MOVE!!!\n" +
                               spacing + "EVERYTHING IS INVERTED\n" +
                               spacing + "**********************\n");
            for(int a = 0; a < board.length; a++) {
                for(int b = 0; b < board[a].length; b++) {
                    if(board[a][b] == "X")
                        board[a][b] = "O";
                    else if(board[a][b] == "O")
                        board[a][b] = "X";
                }
            }
            notFinished = false;
            invertChance = 0;
            inverted = !inverted;
        }
        // clears column
        if(drill) {
            System.out.println("\n" + spacing + "**************\n" +
                               spacing + "DRILL MOVE!!!\n" +
                               spacing + "COLUMN CLEARED\n" +
                               spacing + "**************\n");
           for(int f = 0; f < board.length; f++) {
               board[f][play] = " ";
           }
           notFinished = false;
           drillChance = 0;
        }
        if(!notFinished){
            invertChance++;
            drillChance++;
            break outer;
        }
    }
    // in case the column the player chose is filled
    if(notFinished) {
        System.out.println("INVALID! Please try again.");
        updateBoard(board, askForPlay(in), player);
    }
    return board;
}

// gets the next play
public static int askForPlay(Scanner in) {
    System.out.print("Which column would you like to place into? ");
    int play = Integer.parseInt(in.next().substring(0, 1));
    while(play < 1 || play > 7) {
        System.out.print("INVALID! Retry:\nWhich column would you like to place into? ");
        play = Integer.parseInt(in.next().substring(0, 1));
    }
    return play;
}

// multiplayer mode
public static void multiplayer(String[][] board) {
    int player = 1;
    while(true) {
        // player 1
        printBoard(board);
        System.out.println("\nPlayer 1:");
        board = updateBoard(board, askForPlay(in), player);            
        if(winPlay(board, "Player 1", "Player 2"))
            break;
        if(checkDraw(board)){
            System.out.println("You're all bad at this");
            break;
        }

        player = 2;

        // player 2
        printBoard(board);
        System.out.println("\nPlayer 2:");
        board = updateBoard(board, askForPlay(in), player);            
        if(winPlay(board, "Player 2", "Player 1"))
            break;
        if(checkDraw(board)){
            System.out.println("You're all bad at this");
            break;
        }
        player = 1;
    }
    /* FIXME
    Scanner in = new Scanner(System.in);
    System.out.print("Would you like to play again? ");
    String again = in.next().substring(0, 1);
    in.close();
    if(again.equalsIgnoreCase("y"))
        new C4caller().start();
    else
        System.out.println("Alright. Have a nice day!");
    */
}

// singleplayer as player 1
public static void playerOne(String[][] board) {
    int player = 1;
    while(true) {
        // player 1
        printBoard(board);
        System.out.println("\nPlayer 1:");
        board = updateBoard(board, askForPlay(in), player);            
        if(winPlay(board, "Player 1", "AI"))
            break;
        if(checkDraw(board)){
            System.out.println("You're all bad at this");
            break;
        }
        player = 2;

        // player 2
        printBoard(board);
        System.out.println("\nAI:");
        board = updateBoard(board, AI(new Random(), board), player);            
        if(winPlay(board, "AI", "Player 1"))
            break;
        player = 1;
    }
    /* FIXME
    Scanner in = new Scanner(System.in);
    System.out.print("Would you like to play again? ");
    String again = in.next().substring(0, 1);
    in.close();
    if(again.equalsIgnoreCase("y"))
        new C4caller().start();
    else
        System.out.println("Alright. Have a nice day!");
    */
}

// singleplayer as player 2
public static void playerTwo(String[][] board) {
    int player = 1;
    while(true) {
        // player 1
        printBoard(board);
        System.out.println("\nAI:");
        board = updateBoard(board, AI(new Random(), board), player);            
        if(winPlay(board, "AI", "Player 2"))
            break;
        if(checkDraw(board)){
            System.out.println("You're all bad at this");
            break;
        }
        player = 2;

        // player 2
        printBoard(board);
        System.out.println("\nPlayer 2:");
        board = updateBoard(board, askForPlay(in), player);            
        if(winPlay(board, "Player 2", "AI"))
            break;
        if(checkDraw(board)){
            System.out.println("You're all bad at this");
            break;
        }
        player = 1;
    }
    /* FIXME
    Scanner in = new Scanner(System.in);
    System.out.print("Would you like to play again? ");
    String again = in.next().substring(0, 1);
    in.close();
    if(again.equalsIgnoreCase("y"))
        new C4caller().start();
    else
        System.out.println("Alright. Have a nice day!");
    */
}

// prints out the winning play
public static boolean winPlay(String[][] board, String player, String otherPlayer) {
    if(checkForWinner(board)) {
            printBoard(board);
            if(!inverted)
                System.out.println(otherPlayer + " won!");
            else
                System.out.println(player + " won!");
    }
    return(checkForWinner(board));
}

public static void playAgain() {
    Scanner in = new Scanner(System.in);
    System.out.print("Would you like to play again? ");
    String again = in.next().substring(0, 1);
    in.close();
    if(again.equalsIgnoreCase("y"))
        new Connect4().start();
    else
        System.out.println("Alright. Have a nice day!");
}

public static boolean checkDraw(String[][] board) {
    for(int n = 0; n < board.length; n++) {
        for(int a = 0; a < board[n].length; a++) {
            if(board[n][a] == " ")
                return false;
        }
    }
    return true;
}

}