feat: read and apply user moves

2 files changed, 55 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
index 62b4692..931d1df 100644
--- a/src/main.c
+++ b/src/main.c
@@ -82,10 +82,59 @@ void parse_FEN(char* FEN, int board[BOARD_SIZE][BOARD_SIZE]) {
   }
 }
 
+int notation_to_position(int file, int rank) {
+  return ((rank - 1) << 3) + (file - 'a');
+}
+
+void position_to_notation(int position, char notation[2]) {
+  notation[0] = (position & FILE_MASK) + 'a';
+  notation[1] = (position >> 3) + '1';
+}
+
+int positions_to_move(int origin, int destination) {
+  return (origin << 6) + destination;
+};
+
+void print_move(int move) {
+  char move_in_notation[5] = "xy XY";
+  position_to_notation(move >> 6, move_in_notation);
+  position_to_notation(move & DESTINATION_MASK, move_in_notation + 3);
+  printf("%s\n", move_in_notation);
+};
+
+int input_move() {
+  char file;
+  int rank;
+  char file_destination;
+  int rank_destination;
+
+  scanf(" %c%i %c%i", &file, &rank, &file_destination, &rank_destination);
+
+  int pos = notation_to_position(file, rank);
+  int pos_destination = notation_to_position(file_destination, rank_destination);
+
+  return positions_to_move(pos, pos_destination);
+};
+
+void apply_move(int move, int* board) {
+  int origin = move >> 6;
+  int destination = move & DESTINATION_MASK;
+
+  board[destination] = board[origin];
+  board[origin] = EMPTY;
+}
+
 int main() {
   int board[BOARD_SIZE][BOARD_SIZE];
   parse_FEN(DEFAULT_FEN, board);
   print_board(board);
 
+  int move;
+  while (1) {
+    move = input_move();
+    apply_move(move, (int *)board);
+    print_board(board);
+  }
+
 	return 0;
 }
diff --git a/src/pieces.h b/src/pieces.h
index 10d4eec..f8e50e7 100644
--- a/src/pieces.h
+++ b/src/pieces.h
@@ -22,3 +22,9 @@ char* pieces[] = {
   "♚", "♔",
 };
 
+
+#define RANK_MASK 0b111000
+#define FILE_MASK 0b000111
+
+#define ORIGIN_MASK      0b111111000000
+#define DESTINATION_MASK 0b000000111111