Create rules/lbw_engine.py

rules/lbw_engine.py

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+"""Implements ICC LBW rules & umpire‑call margin."""
+
+from typing import Dict
+
+
+class LBWEngine:
+    def __init__(self, margin_mm: float = 20.0):
+        self.margin = margin_mm
+
+    def decide(self, event_meta: Dict):
+        """Return verdict ('OUT', 'NOT OUT', 'UMPIRE CALL') with reasoning."""
+        pitch_zone = event_meta["pitch_zone"]  # 'inline', 'outside_off', 'outside_leg'
+        impact_zone = event_meta["impact_zone"]
+        projected_hit = event_meta["hits_stumps"]  # bool
+
+        if pitch_zone == "outside_leg":
+            return "NOT OUT", "Ball pitched outside leg"
+        if impact_zone != "in_line":
+            return "NOT OUT", "Impact outside off and shot offered" if event_meta.get("shot_offered") else "NOT OUT"
+        if projected_hit:
+            return "OUT", "All three criteria satisfied"
+        else:
+            return "UMPIRE CALL", "Missing stumps within margin"