fix(rules): firing into melee exemption measured target-to-nearest-ally, not attacker-to-target (SRD Shooting into a Melee)

src/pf1e_simulator/combat.py

@@ -3056,18 +3056,22 @@ class CombatEngine:
         self, attacker: CombatantState, target: CombatantState
     ) -> int:
         """PF1e firing into melee: -4 on a ranged attack whose target is
-        engaged in melee, avoided entirely (0) when the target or every
-        threatening opponent stands 10+ ft from the attacker. Precise Shot
-        removes it.
+        engaged in melee, avoided entirely (0) when the target stands 10+ ft
+        from every friendly character of the attacker. Precise Shot removes
+        it.
 
         PF1e (SRD "Attack" — Shooting or Throwing into a Melee): "If your
         target (or the part of your target you're aiming at, if it's a big
         target) is at least 10 feet away from the nearest friendly character,
-        you can avoid the -4 penalty" — the 10+ ft clause is therefore 0, not
-        -2. The -2 applies only when the target is two size categories larger
-        than the friendly characters it is engaged with (and 0 at three or
-        more): size-category reduction is NOT modeled (documented
-        simplification).
+        you can avoid the -4 penalty" — the exemption is measured from the
+        TARGET to the attacker's nearest friendly character (a creature on
+        the attacker's side other than the attacker), NOT from the attacker's
+        own position; an archer 30 ft away still takes the -4 when the target
+        is locked in melee with one of the archer's allies at 5 ft. The 10+
+        ft clause is therefore 0, not -2. The -2 applies only when the target
+        is two size categories larger than the friendly characters it is
+        engaged with (and 0 at three or more): size-category reduction is
+        NOT modeled (documented simplification).
 
         The target is engaged when an active enemy of the target (not the
         attacker itself) threatens the target's occupied cells with a melee
@@ -3085,12 +3089,17 @@ class CombatEngine:
         ]
         if not threats:
             return 0
-        if self.creature_distance(attacker, target) * _SQUARE_FT >= _FIRING_MELEE_SAFE_FT:
+        allies = [
+            s
+            for s in self._states
+            if s is not attacker and s.active and s.side == attacker.side
+        ]
+        if all(
+            self.creature_distance(target, ally) * _SQUARE_FT
+            >= _FIRING_MELEE_SAFE_FT
+            for ally in allies
+        ):
             return 0
-        for threat in threats:
-            dist = self.creature_distance(attacker, threat) * _SQUARE_FT
-            if dist >= _FIRING_MELEE_SAFE_FT:
-                return 0
         return _FIRING_MELEE_PENALTY
 
     def _engaged_in_melee(self, state: CombatantState) -> bool: