othello.c

/*
 ============================================================================
 Name        : Othello.c
 Author      : Chris Cirefice
 Version     : 1.0
 Description : Othello (Reversi) in C
 ============================================================================
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "othello_engine.h"

int main(int numArgs, const char *args[]) {

    setvbuf(stdout, NULL, 0, _IONBF);

    if (numArgs != 5) {
        printf("Invalid number of arguments. Use the following command form:\n");
        printf("othello board_size start_player disc_color\n");
        printf("Where:\nboard_size is an even number between 6 and 10 (inclusive)\nstart_player is 1 or 2\ndisc_color is 'B' ('b') or 'W' ('w')");
        return EXIT_FAILURE;
    }
    else if (strcmp(args[1], "othello") != 0) {
        printf("Please start the command using the keyword 'othello'");
        return EXIT_FAILURE;
    }
    else if (atoi(args[2]) < 6 || atoi(args[2]) > 10 || atoi(args[2]) % 2 != 0) {
        printf("board_size must be an even number between 6 and 10");
        return EXIT_FAILURE;
    }
    else if (atoi(args[3]) < 1 || atoi(args[3]) > 2) {
        printf("start_player must be 1 or 2");
        return EXIT_FAILURE;
    }
    else if (args[4][0] != 'B' && args[4][0] != 'b' && args[4][0] != 'W' && args[4][0] != 'w') {
        printf("disc_color must be 'B', 'b', 'W', or 'w'");
        return EXIT_FAILURE;
    }

    // --------------------------- End checking for bad commands --------------------------- //

    // -------------------------- Initialize the Othello routine --------------------------- //

    // Create the board
    int size = atoi(args[2]);
    char board[size][size];
    char playerColor = args[4][0];

    // Initialize all elements to 'e'
    for (int i = 0; i < size; i ++) {
        for (int j = 0; j < size; j ++) {
            board[i][j] = 'e';
        }
    }

    // Set starting black pieces ('B')
    if (playerColor == 'B') {
        board[(size/2)-1][(size/2)-1] = 'B';
        board[size/2][size/2] = 'B';
    }
    else {
        board[(size/2)-1][(size/2)-1] = 'W';
        board[size/2][size/2] = 'W';
    }

    // Set starting white pieces ('W')
    if (playerColor == 'B') {
        board[(size/2)-1][size/2] = 'W';
        board[size/2][(size/2)-1] = 'W';
    }
    else {
        board[(size/2)-1][size/2] = 'B';
        board[size/2][(size/2)-1] = 'B';
    }

    // Display game start message
    if (playerColor == 'B' || playerColor == 'b')
        printf("Othello game with a %dx%d board - Player %d with black disc to start\n\n", size, size, atoi(args[3]));
    else
        printf("Othello game with a %dx%d board - Player %d with white disc to start\n\n", size, size, atoi(args[3]));

    // --------------------------- Start the game through user input --------------------------- //

    // Assign game mechanic variables
    int currentPlayer = atoi(args[3]);
    int boardFull = 0;
    int endOfGame = 0;

    displayBoard(size, board);

    // Start the game
    do {
        // Assign default values for the turn
        boardFull = boardIsFull(size, board);

        // If board is full, break out and tally the score!
        if (boardFull) break;

        // Check valid moves for the current player
        Coordinate *validMovesForTurn = movesAvailable(playerColor, size, board);
        Coordinate *root = validMovesForTurn; // Keep a start-of-list placeholder
        //validMovesForTurn = validMovesForTurn->next; // Skip first junk value

        // If the current player has no moves, check the other player
        if (validMovesForTurn == NULL) {
            printf("Player %d has no moves... Swapping to other player\n\n", currentPlayer);
            swapPlayer(&currentPlayer, &playerColor);
            // If the other player has no valid moves, mark the game as over
            // Otherwise, continue normal play
            validMovesForTurn = movesAvailable(playerColor, size, board);
            validMovesForTurn = validMovesForTurn->next; // Skip first junk value
            if (validMovesForTurn == NULL) {
                printf("Player %d also has no moves... I guess that means game over!!!\n\n", currentPlayer);
                endOfGame = 1;
            }
        }

        if (endOfGame) break;

        Coordinate desiredLocation;
        validMovesForTurn = validMovesForTurn->next; // Skip first trash element (-1, -1)

        // Keep checking for valid input/re-prompt on invalid
        do {
            printf("\nHint - your valid moves are: \n\n");
            while (validMovesForTurn != NULL) {
                printf("{%d, %d} ", validMovesForTurn->x, validMovesForTurn->y);
                validMovesForTurn = validMovesForTurn->next;
            }
            printf("\n\n");
            // Reset at root (but skip first element again because it's garbage
            validMovesForTurn = root->next;
            desiredLocation = promptPlayer(currentPlayer);
        } while (!isValidMove(desiredLocation, validMovesForTurn));

        // Flip disks at coordinate desiredLocation here
        flipDiscs(desiredLocation, playerColor, size, board);

        // Display the board after the turn has been taken
        printf("\n\n");
        displayBoard(size, board);

        // Swap player (end current player's turn)
        swapPlayer(&currentPlayer, &playerColor);
        freeList(validMovesForTurn);
    }
    while (!boardFull);

    Score score = tallyScore(size, board);
    printf("**********Results**********\n\n");
    printf("The score was %d - %d (B - W)", score.b, score.w);

    // TODO: Add out-of-bounds check to validMoves function before actually creating those nodes (off-by-1 error)
    return EXIT_SUCCESS;
}