feat: initialize majiang-rl project

majiang_rl/tiles.py

@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+from typing import Iterable, List, Tuple
+
+SUITS = ("wan", "tong", "suo")
+WINDS = ("east", "south", "west", "north")
+DRAGONS = ("red", "green", "white")
+FLOWERS = (
+    "plum",
+    "orchid",
+    "chrysanthemum",
+    "bamboo",
+    "spring",
+    "summer",
+    "autumn",
+    "winter",
+)
+
+# 34 suited + honors, plus 8 flowers = 42
+TILE_TYPES: List[str] = []
+for suit in SUITS:
+    for rank in range(1, 10):
+        TILE_TYPES.append(f"{suit}_{rank}")
+for wind in WINDS:
+    TILE_TYPES.append(f"wind_{wind}")
+for dragon in DRAGONS:
+    TILE_TYPES.append(f"dragon_{dragon}")
+for flower in FLOWERS:
+    TILE_TYPES.append(f"flower_{flower}")
+
+SUITED_RANGE = range(0, 27)
+HONOR_RANGE = range(27, 34)
+FLOWER_RANGE = range(34, 42)
+
+def build_wall(rng) -> List[int]:
+    wall: List[int] = []
+    for tile_id in range(34):
+        wall.extend([tile_id] * 4)
+    for tile_id in FLOWER_RANGE:
+        wall.append(tile_id)
+    rng.shuffle(wall)
+    return wall
+
+
+def is_flower(tile_id: int) -> bool:
+    return tile_id in FLOWER_RANGE
+
+
+def tile_name(tile_id: int) -> str:
+    return TILE_TYPES[tile_id]
+
+
+def counts_from_tiles(tiles: Iterable[int], size: int = 42) -> List[int]:
+    counts = [0] * size
+    for tile_id in tiles:
+        counts[tile_id] += 1
+    return counts
+
+
+def split_suit_index(tile_id: int) -> Tuple[int, int] | None:
+    if tile_id not in SUITED_RANGE:
+        return None
+    suit = tile_id // 9
+    rank = tile_id % 9
+    return suit, rank