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#include <stdio.h>
#include <stdlib.h>
#include "myarray.h"
#include "mystring.h"

enum {
    O_PIECE,
    X_PIECE,
    EMPTY_PIECE,
};

const char piece[EMPTY_PIECE + 1] = {'O', 'X', ' '};

void print_field(MArray field) {
    int i;
    printf("    1   2   3\n");
    printf("  +---+---+---+\n");
    for (i = 0; i < field->len; i++) {
        if (i % 3 == 0) {
            printf("%d ", i / 3 + 1);
        }
        printf("%c| %c", i % 3 != 0 ? ' ' : '\0', piece[myarray_get(field, int, i)]);
        if (i % 3 == 2) {
            printf(" |\n  +---+---+---+\n");
        }
    }
}

MArray field_new() {
    MArray field = myarray_new(9, 1, sizeof(char));
    int i;
    int piece = EMPTY_PIECE;
    for (i = 0; i < 9; i++) {
        myarray_append(field, piece);
    }

    return field;
}

unsigned int coords_to_index(unsigned int x, unsigned int y) {
    return (x - 1) + (y - 1) * 3;
}

int get_winner(MArray field) {
    int i, j;
    int a1;
    int a2;
    int a3;
    int a4;
    int b1;
    int b2;
    int b3;
    int b4;
    for (i = 1; i < 4; i++) {
        a1 = 0;
        a2 = 0;
        a3 = 0;
        a4 = 0;
        b1 = 0;
        b2 = 0;
        b3 = 0;
        b4 = 0;
        for (j = 1; j < 4; j++) {
            switch (myarray_get(field, int, coords_to_index(i, j))) {
                case O_PIECE:
                    a1++;
                    break;
                case X_PIECE:
                    b1++;
                    break;
            }
            switch (myarray_get(field, int, coords_to_index(j, i))) {
                case O_PIECE:
                    a2++;
                    break;
                case X_PIECE:
                    b2++;
                    break;
            }
        }
        switch (myarray_get(field, int, coords_to_index(i, i))) {
            case O_PIECE:
                a3++;
                break;
            case X_PIECE:
                b3++;
                break;
        }
        switch (myarray_get(field, int, coords_to_index(4-i, i))) {
            case O_PIECE:
                a4++;
                break;
            case X_PIECE:
                b4++;
                break;
        }
        if (a1 == 3 || a2 == 3 || a3 == 3 || a4 == 3) return O_PIECE;
        if (b1 == 3 || b2 == 3 || b3 == 3 || b4 == 3) return X_PIECE;
    }
    return EMPTY_PIECE;
}

unsigned int prompt(MArray field, unsigned int player) {
    char x, y;
    unsigned int index;
    MString input = mystring_new(2, 1);
    while (1) {
        printf("Enter coordinates for your piece, player %c: ", piece[player]);
        mystring_clear(input);
        mystring_getline(input, stdin);
        switch (sscanf(input->str, "%c%c", &x, &y)) {
            case EOF:
                printf("\n");
                exit(EXIT_SUCCESS);
                break;
            case 2:
                index = coords_to_index(x - '0', y - '0');
                if (index >= 9 || index < 0 || myarray_get(field, int, index) != EMPTY_PIECE) continue;
                mystring_free(input);
                return index;
        }
    }
}

int main(int argc, char **argv) {
    MArray field = field_new();
    int player = 0;
    unsigned int index;

    while (1) {
        print_field(field);
        if (get_winner(field) != EMPTY_PIECE) break;
        index = prompt(field, player);
        myarray_get(field, int, index) = player;
        player ^= 1;
    }

    printf("Player %c won!\n", get_winner(field) == O_PIECE ? piece[O_PIECE] : piece[X_PIECE]);

    myarray_free(field);
    return 0;
}