refactor: derive turtle opcodes from classic

tools/opcode_map_utils.py

@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+
+from __future__ import annotations
+
+import json
+import re
+from pathlib import Path
+from typing import Dict, Set
+
+
+RE_OPCODE_NAME = re.compile(r"^(?:CMSG|SMSG|MSG)_[A-Z0-9_]+$")
+
+
+def load_opcode_map(path: Path, _seen: Set[Path] | None = None) -> Dict[str, str]:
+    if _seen is None:
+        _seen = set()
+
+    path = path.resolve()
+    if path in _seen:
+        chain = " -> ".join(str(p) for p in list(_seen) + [path])
+        raise ValueError(f"Opcode map inheritance cycle: {chain}")
+    _seen.add(path)
+
+    data = json.loads(path.read_text())
+    merged: Dict[str, str] = {}
+
+    extends = data.get("_extends")
+    if isinstance(extends, str) and extends:
+        merged.update(load_opcode_map(path.parent / extends, _seen))
+
+    remove = data.get("_remove", [])
+    if isinstance(remove, list):
+        for name in remove:
+            if isinstance(name, str):
+                merged.pop(name, None)
+
+    for key, value in data.items():
+        if not isinstance(key, str) or not RE_OPCODE_NAME.match(key):
+            continue
+        if isinstance(value, str):
+            merged[key] = value
+        elif isinstance(value, int):
+            merged[key] = str(value)
+
+    _seen.remove(path)
+    return merged