#include "game_core.h"
#include <stdlib.h>

const int directions[8][2] = {{-1, -1}, {-1, 0}, {-1, 1}, {0, -1},
                              {0, 1},   {1, -1}, {1, 0},  {1, 1}};

const uint32_t colors[2] = {BLACK, WHITE};

Board init_board(size_t width, size_t height, int random) {
  Board board = {NULL, width, height};
  board.pixels = malloc(height * sizeof(uint32_t *));
  for (size_t y = 0; y < height; y++) {

    board.pixels[y] = malloc(width * sizeof(uint32_t));
    for (size_t x = 0; x < width; x++) {
      if (random)
        board.pixels[y][x] = colors[rand() % 2];
      else
        board.pixels[y][x] = BLACK;
    }
  }
  return board;
}

void free_board(Board board) {
  for (size_t y = 0; y < board.height; y++)
    free(board.pixels[y]);
  free(board.pixels);
}

Board copy_board(Board board) {
  Board copy = init_board(board.width, board.height, 0);
  for (size_t x = 0; x < board.width; x++) {
    for (size_t y = 0; y < board.height; y++) {
      copy.pixels[y][x] = board.pixels[y][x];
    }
  }
  return copy;
}

void display_board(Board board) {
  for (size_t y = 0; y < board.height; y++) {
    for (size_t x = 0; x < board.width; x++) {
      printf("%c", board.pixels[y][x] == BLACK ? ' ' : 'X');
    }
    puts("");
  }
}

int count_adjacent(Board board, size_t x, size_t y) {
  size_t i;
  int w, h;
  uint8_t count = 0;
  for (i = 0; i < 8; i++) {
    w = x + directions[i][1];
    h = y + directions[i][0];
    if (!((w < 0 || w >= (int)board.width) ||
          (h < 0 || h >= (int)board.height)))
      if (board.pixels[h][w] == WHITE)
        count++;
  }
  return count;
}

Board process_game(Board board) {
  Board new_board = copy_board(board);
  size_t x, y;
  uint8_t count = 0;
  for (y = 0; y < board.height; y++) {
    for (x = 0; x < board.width; x++) {
      count = count_adjacent(board, x, y);
      if (board.pixels[y][x] == BLACK && count == 3) {
        new_board.pixels[y][x] = WHITE;
      } else if (board.pixels[y][x] == WHITE && count != 2 && count != 3) {
        new_board.pixels[y][x] = BLACK;
      }
    }
  }
  free_board(board);
  return new_board;
}