#include <conio.h>
#include <stdio.h>
#include <stdlib.h>

#include "consts.h"
#include "protos.h"

SOLUTION is_board_solved(BOARD board) {
    char cases[8] = {EMPTY};
    char i;

    // rows and cols
    for (i = 0; i < 3; i++) {
        cases[i] = board[i][0] * board[i][1] * board[i][2];
        cases[i + 3] = board[0][i] * board[1][i] * board[2][i];
    }

    // diagonals
    cases[6] = board[0][0] * board[1][1] * board[2][2];
    cases[7] = board[0][2] * board[1][1] * board[2][0];

    // check cases for winner
    for (i = 0; i < 8; i++) {
        if (cases[i] == 1) {
            // X won
            return X_WON;
        } else if (cases[i] == 8) {
            // O won
            return O_WON;
        }
    }

    // check cases for remaining moves
    for (i = 0; i < 9; i++) {
        if (cases[i] == EMPTY) {
            // more spaces left; game continues
            return MOVES_LEFT;
        }
    }

    // stalemate
    return TIE;
}

void print_board(BOARD board) {
    char i, j;

    printf("\n");
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            printf("%d ", board[i][j]);
        }
        printf("\n");
    }
}

void opponent_move(BOARD board, DIFFICULTY difficulty) {
    char move, move_x, move_y;
    printf("Opponent is moving...");

    // take winning moves (medium)
    // if (difficulty > EASY) {
    // }

    // prevent winning move (hard)
    // if (difficulty > MEDIUM) {
    // }

    // take random move (easy)
    do {
        move = rand() % 9;
        move_x = move % 3;
        move_y = move / 3;
    } while (board[move_y][move_x] != EMPTY);

    board[move_y][move_x] = O;
}

void print_endgame(SOLUTION solution) {
    switch (solution) {
        case X_WON:
            printf("X won");
            break;
        case O_WON:
            printf("O won");
            break;
        case TIE:
            printf("Stalemate");
            break;
    }
    printf("\n");
}

void player_move(BOARD board) {
    char move = EMPTY;
    char move_x = EMPTY;
    char move_y = EMPTY;

    do {
        printf("\nEnter a valid move...");

        move = cgetc() - '0' - 1;
        printf("%d\n", move);
        move_x = move % 3;
        move_y = move / 3;
    } while (0 <= move_x <= move_y <= 2 && board[move_y][move_x] != EMPTY);

    board[move_y][move_x] = X;
}

int main() {
    SOLUTION solution = MOVES_LEFT;
    char move = EMPTY;
    char move_x = EMPTY;
    char move_y = EMPTY;
    BOARD board = {{EMPTY}, {EMPTY}, {EMPTY}};

    cursor(1);
    print_board(board);

    do {
        player_move(board);
        print_board(board);

        if ((solution = is_board_solved(board)) == MOVES_LEFT) {
            opponent_move(board, EASY);
            print_board(board);
        }

    } while (solution == MOVES_LEFT);

    print_endgame(solution);
    return 0;
}