Refactor file structure, and make file

src/connect4.c

@@ -0,0 +1,188 @@
+#include "connect4.h"
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+struct Board *make_board(size_t height, size_t width) 
+{
+  struct Board *new_board = malloc(sizeof(*new_board));
+  if (!new_board)
+    return NULL;
+  new_board->tilemap = calloc(height*width, sizeof(*(new_board->tilemap)));
+  if (!new_board->tilemap)
+    goto out_tilemap;
+  new_board->tile_heights = calloc(width, sizeof(*(new_board->tile_heights)));
+  if (!new_board->tile_heights)
+    goto out_tile_heights;
+
+  new_board->height = height;
+  new_board->width = width;
+  new_board->next_player = RED;
+
+  return new_board;
+
+out_tile_heights:
+  free(new_board->tilemap);
+out_tilemap:
+  free(new_board);
+  return NULL;
+}
+
+void free_board(struct Board *board)
+{
+  free(board->tile_heights);
+  free(board->tilemap);
+  free(board);
+}
+
+int check_for_win_horizontal(struct Board *board, size_t pos_i, size_t pos_j)
+{
+  enum Tile current_player = board->next_player * -1;
+  char in_a_row = 1;
+  // Right
+  size_t npos_i = pos_i + 1;
+  while (npos_i < board->width && IDX(npos_i, pos_j, board) == current_player) {
+    in_a_row++;
+    npos_i++;
+    if (in_a_row >= 4)
+      return 1;
+  }
+  // Left
+  npos_i = pos_i - 1;
+  while (npos_i < board->width && IDX(npos_i, pos_j, board) == current_player) {
+    in_a_row++;
+    npos_i--;
+    if (in_a_row >= 4)
+      return 1;
+  }
+  return 0;
+}
+
+int check_for_win_vertical(struct Board *board, size_t pos_i, size_t pos_j)
+{
+  enum Tile current_player = board->next_player * -1;
+  char in_a_row = 1;
+  // Down
+  size_t npos_j = pos_j + 1;
+  while (npos_j < board->height && \
+      IDX(pos_i, npos_j, board) == current_player) {
+    in_a_row++;
+    npos_j++;
+    if (in_a_row >= 4)
+      return 1;
+  }
+  return 0;
+}
+
+int check_for_win_lr_diagonal(struct Board *board, size_t pos_i, size_t pos_j)
+{
+  enum Tile current_player = board->next_player * -1;
+  char in_a_row = 1;
+  // Down-right
+  size_t npos_i = pos_i + 1;
+  size_t npos_j = pos_j + 1;
+  while (npos_i < board->width && npos_j < board->height &&
+      IDX(npos_i, npos_j, board) == current_player) {
+    in_a_row++;
+    npos_i++;
+    npos_j++;
+    if (in_a_row >= 4)
+      return 1;
+  }
+  // Up-left
+  npos_i = pos_i - 1;
+  npos_j = pos_j - 1;
+  while (npos_i < board->width && npos_j < board->height &&
+      IDX(npos_i, npos_j, board) == current_player) {
+    in_a_row++;
+    npos_i--;
+    npos_j--;
+    if (in_a_row >= 4)
+      return 1;
+  }
+
+  return 0;
+}
+
+int check_for_win_rl_diagonal(struct Board *board, size_t pos_i, size_t pos_j)
+{
+  enum Tile current_player = board->next_player * -1;
+  char in_a_row = 1;
+  // Down-left
+  size_t npos_i = pos_i - 1;
+  size_t npos_j = pos_j + 1;
+  while (npos_i < board->width && npos_j < board->height &&
+      IDX(npos_i, npos_j, board) == current_player) {
+    in_a_row++;
+    npos_i--;
+    npos_j++;
+    if (in_a_row >= 4)
+      return 1;
+  }
+  // Up-right
+  npos_i = pos_i + 1;
+  npos_j = pos_j - 1;
+  while (npos_i < board->width && npos_j < board->height &&
+      IDX(npos_i, npos_j, board) == current_player) {
+    in_a_row++;
+    npos_i++;
+    npos_j--;
+    if (in_a_row >= 4)
+      return 1;
+  }
+
+  return 0;
+}
+
+int check_for_win(struct Board *board, size_t pos_i, size_t pos_j)
+{
+  if (check_for_win_horizontal(board, pos_i, pos_j))
+      return 1;
+  if (check_for_win_vertical(board, pos_i, pos_j))
+      return 1;
+  if (check_for_win_lr_diagonal(board, pos_i, pos_j))
+      return 1;
+  if (check_for_win_rl_diagonal(board, pos_i, pos_j))
+      return 1;
+  return 0;
+}
+
+int drop_tile(struct Board *board, size_t drop_pos)
+{
+  if (drop_pos >= board->width)
+    return -1;
+
+  size_t tower_height = board->height-board->tile_heights[drop_pos]-1;
+
+  if (tower_height > board->height)
+    return -1;
+
+  IDX(drop_pos, tower_height, board) = board->next_player;
+
+  board->tile_heights[drop_pos]++;
+  board->next_player *= -1;
+
+  return check_for_win(board, drop_pos, tower_height);
+}
+
+void print_board(struct Board *board)
+{
+  for (int j = 0; j < board->height; j++) {
+    printf("|");
+    for (int i = 0; i < board->width; i++) {
+      switch (IDX(i,j,board)) {
+      case BLACK:
+        printf("\033[90m");
+        break;
+      case RED:
+        printf("\033[31m");
+        break;
+      case EMPTY:
+        printf("\033[36m");
+      }
+      printf("O");
+    }
+    printf("\033[0m|\n");
+  }
+  printf("\n");
+}

src/main.c

@@ -0,0 +1,17 @@
+#include "connect4.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+  struct Board *my_board = make_board(6, 7);
+  int drop_spot = 0;
+  do {
+    print_board(my_board);
+    printf("Where to drop? ");
+    scanf("%d",&drop_spot);
+  } while (!drop_tile(my_board, drop_spot-1));
+  print_board(my_board);
+  printf("Congratulations!");
+  return EXIT_SUCCESS;
+}