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

char** game;
void print_game(void);

int check_winner(void) {

    // check vertical
    for (int row = 6; row > 0; row--) {
        for (int col = 6; col > 0; col--) {
            if (game[row][col] == '1') {
                if (game[row-1][col] == '1') {
                    if (game[row-2][col] == '1') {
                        if (game[row-3][col] == '1') {
                            return 1;
                        }
                    }
                }
            }
            if (game[row][col] == '2') {
                if (game[row-1][col] == '2') {
                    if (game[row-2][col] == '2') {
                        if (game[row-3][col] == '2') {
                            return 2;
                        }
                    }
                }
            }
        }
    }
    // check horizontal
    for (int row = 6; row > 0; row--) {
        for (int col = 6; col > 0; col--) {
            if (game[row][col] == '1') {
                if (game[row][col-1] == '1') {
                    if (game[row][col-2] == '1') {
                        if (game[row][col-3] == '1') {
                            return 1;
                        }
                    }
                }
            }
            if (game[row][col] == '2') {
                if (game[row][col-1] == '2') {
                    if (game[row][col-2] == '2') {
                        if (game[row][col-3] == '2') {
                            return 2;
                        }
                    }
                }
            }
        }
    }
    // check diagonal
    for (int row = 6; row > 0; row--) {
        for (int col = 6; col > 0; col--) {
            if (game[row][col] == '1') {
                if (game[row-1][col-1] == '1') {
                    if (game[row-2][col-2] == '1') {
                        if (game[row-3][col-3] == '1') {
                            return 1;
                        }
                    }
                }
            }
            if (game[row][col] == '2') {
                if (game[row-1][col-1] == '2') {
                    if (game[row-2][col-2] == '2') {
                        if (game[row-3][col-3] == '2') {
                            return 2;
                        }
                    }
                }
            }
        }
    }
    return 0;
}

int make_move(int move, int turn) {

    for (int row = 0; row < 7; row++) {

        /* Theres already another counter in this column */
        if (game[row][move] == '1' || game[row][move] == '2') {
            /* Check its not the top row */
            if (row == 0) {
                printf("Column full, try again\n");
                return 0;
            /* Otherwise add it to the column */
            } else {
                if (!turn) {
                    game[row-1][move] = '2';
                } else {
                    game[row-1][move] = '1';
                }
                break;
            }
        /* Empty cell, but not the bottom row */
        } else if ((game[row][move] == ' ') && (row != 6)) {
            continue;
        /* Empty cell and also the bottom row */
        } else {
            if (!turn) {
                game[row][move] = '2';
            } else {
                game[row][move] = '1';
            }
            break;
        }
    }
    if (check_winner() == 1) {
        print_game();
        printf("Player 1 wins!\n");
        exit(0);
    } else if (check_winner() == 2){
        print_game();
        printf("Player 2 wins!\n");
        exit(0);
    } else {
        print_game();
    }
    return 1;
}

void play_game(void) {

    char buffer[256];
    int move;
    int turn = 0;

    while (1) {
        if (!turn) {
            printf("Player 1> ");
            turn = 1;
        } else {
            printf("Player 2> ");
            turn = 0;
        }
        fflush(stdout);
        if (fgets(buffer, 254, stdin) != NULL) {
            if (buffer[0] == '\n') {
                turn = !turn;
                continue;
            }
            if (isdigit(buffer[0]) && buffer[1] == '\n' && buffer[2] == '\0') {
                if (buffer[0] <= '6' && buffer[0] >= '0') {
                    move = (int)strtol(buffer, NULL, 10);
                    if (!make_move(move, turn)) {
                        turn = !turn;
                    }
                } else {
                    printf("Invalid input\n");
                    turn = !turn;
                }
            } else {
                printf("Invalid input\n");
                turn = !turn;
            }


        } else {
            if (feof(stdin)) {
                fprintf(stdout, "Player %d quit\n", turn);
                exit(1);
            }
        }
    }

}

void print_game(void) {

    printf("|0|1|2|3|4|5|6|\n");
    for (int i = 0; i < 7; i++) {
        printf("|%c|%c|%c|%c|%c|%c|%c|\n", game[i][0],
                                            game[i][1],
                                            game[i][2],
                                            game[i][3],
                                            game[i][4],
                                            game[i][5],
                                            game[i][6]);
    }
    printf("|-------------|\n");
}

void setup_game(void) {

    for (int i = 0; i < 7; i++) {
        for (int j = 0; j < 7; j++) {
            game[i][j] = ' ';
        }
    }
}

int main(int argc, const char * argv[]) {


    game = malloc(sizeof(char*) * 7);
    for (int i = 0; i < 7; i++) {
        game[i] = malloc(sizeof(char) * 7);
    }

    setup_game();
    print_game();
    play_game();

    for (int i = 0; i < 7; i++) {
        free(game[i]);
    }
    free(game);
    return 0;
}