enum LevelTile {
  exit,
  door,
  floor,
  wall,
}

class Level {
  Set<(int, int)> openCells = {};
}

LevelTile colorToTile(int c) {
  switch (c) {
    // ABGR
    case 0xFF000000:
    case 0xFF707070:
      return LevelTile.wall;
    case 0xFFFFFFFF:
    case 0xFF00FFFF:
    case 0xFFFF00FF:
      return LevelTile.floor;
    case 0xFFFF8700:
      return LevelTile.door;
    case 0xFF0000FF:
      return LevelTile.exit;
    default:
      throw Exception("unrecognized pixel: $c");
  }
}