add experiment runner

experiment_runner/analysis/critical_state.py

@@ -0,0 +1,60 @@
+"""
+Extracts the board state *before* and *after* a critical phase
+for every critical-analysis run produced by experiment_runner.
+
+Each run must have:
+• lmvsgame.json   – containing a phase named ctx["resume_from_phase"]
+
+Outputs live in  analysis/critical_state/<run_name>_{before|after}.json
+"""
+from __future__ import annotations
+
+import json
+import logging
+from pathlib import Path
+from typing import Dict, List
+
+log = logging.getLogger(__name__)
+
+
+def _phase_by_name(phases: List[dict], name: str) -> dict | None:
+    for ph in phases:
+        if ph["state"]["name"] == name:
+            return ph
+    return None
+
+
+def run(exp_dir: Path, ctx: Dict) -> None:
+    resume_phase = ctx.get("resume_from_phase")
+    if not resume_phase:
+        log.info("critical_state: --resume_from_phase not supplied – skipping")
+        return
+
+    out_dir = exp_dir / "analysis" / "critical_state"
+    out_dir.mkdir(parents=True, exist_ok=True)
+
+    for run_dir in (exp_dir / "runs").iterdir():
+        game_json = run_dir / "lmvsgame.json"
+        if not game_json.exists():
+            continue
+
+        with game_json.open("r") as fh:
+            game = json.load(fh)
+        phases = game.get("phases", [])
+        if not phases:
+            continue
+
+        before = _phase_by_name(phases, resume_phase)
+        after = phases[-1] if phases else None
+        if before is None or after is None:
+            log.warning("Run %s missing expected phases – skipped", run_dir.name)
+            continue
+
+        (out_dir / f"{run_dir.name}_before.json").write_text(
+            json.dumps(before, indent=2)
+        )
+        (out_dir / f"{run_dir.name}_after.json").write_text(
+            json.dumps(after, indent=2)
+        )
+
+    log.info("critical_state: snapshots written to %s", out_dir)