fix(combat): resolve touch attacks against touch AC and firearms

src/pf1e_simulator/combat.py

@@ -114,6 +114,7 @@ _NATURAL_TWENTY = 20  # PF1e: natural 20 always hits and threatens
 _COVER_AC_BONUS = 4  # PF1e: partial cover grants +4 AC
 _RANGE_INCREMENT_PENALTY = 2  # PF1e: -2 per full range increment beyond the first
 _MAX_RANGE_INCREMENTS = 10  # PF1e: projectile weapons shoot up to 10 increments
+_MAX_TOUCH_RANGE_INCREMENTS = 5  # PF1e: thrown/firearm touch weapons shoot up to 5 increments
 _FLANK_BONUS = 2  # PF1e: +2 melee attack when ally threatens opposite side
 _ITERATIVE_PENALTY = 5  # PF1e: each BAB iterative is at -5 from the previous
 _MAX_ITERATIVES = 4  # PF1e: BAB +16 gives 4 attacks (at +16, +11, +6, +1)
@@ -510,17 +511,31 @@ class CombatEngine:
         for weapon in attacker.usable_attacks():
             if weapon.kind in ("melee", "touch") and dist_ft <= weapon.reach_ft:
                 return weapon
+            max_increments = (
+                _MAX_TOUCH_RANGE_INCREMENTS
+                if weapon.kind == "touch"
+                else _MAX_RANGE_INCREMENTS
+            )
             if (
-                weapon.kind == "ranged"
+                weapon.kind in ("ranged", "touch")
                 and weapon.range_increment_ft is not None
-                and dist_ft <= weapon.range_increment_ft * _MAX_RANGE_INCREMENTS
+                and dist_ft <= weapon.range_increment_ft * max_increments
             ):
                 return weapon
         return None
 
+    def _is_ranged_attack(self, weapon: AttackSpec) -> bool:
+        """Ranged-style attack: projectile, or touch thrown/fired from a distance.
+
+        Melee touch attacks (no range increment) are not ranged-style.
+        """
+        return weapon.kind == "ranged" or (
+            weapon.kind == "touch" and weapon.range_increment_ft is not None
+        )
+
     def range_penalty(self, weapon: AttackSpec, dist_ft: int) -> int:
         """PF1e: -2 per full range increment beyond the first, zero within it."""
-        if weapon.kind != "ranged" or weapon.range_increment_ft is None:
+        if weapon.kind not in ("ranged", "touch") or weapon.range_increment_ft is None:
             return 0
         increments = dist_ft // weapon.range_increment_ft
         if dist_ft % weapon.range_increment_ft != 0:
@@ -679,16 +694,34 @@ class CombatEngine:
         flank = self._flanking_bonus(attacker, target) if weapon.kind == "melee" else 0
         base_bonus = bonus_override if bonus_override is not None else weapon.attack_bonus
         atk_mods = self._stat_modifiers(attacker, "attack", weapon_name=weapon.name)
-        if weapon.kind == "ranged" and self._has_condition_named(attacker, "prone"):
+        if self._is_ranged_attack(weapon) and self._has_condition_named(attacker, "prone"):
             atk_mods.append(StatModifier(target="attack", value=-4))
         attack_mod = resolve_modifiers(atk_mods)
         pa_amt = self._power_attack_amt(attacker) if weapon.kind == "melee" else 0
         total = roll + base_bonus + penalty + flank + attack_mod - pa_amt
         # Check if target denies DEX to AC (flat-footed)
-        if self.has_condition_flag(target, "denies_dex_to_ac"):
-            base_ac = target.combatant.ac.flat_footed
+        denies_dex = self.has_condition_flag(target, "denies_dex_to_ac")
+        full_ac_base = (
+            target.combatant.ac.flat_footed
+            if denies_dex
+            else target.combatant.ac.total
+        )
+        # Touch resolves vs touch AC; firearms beyond their first increment use full AC.
+        if weapon.kind == "touch":
+            if (
+                weapon.firearm
+                and weapon.range_increment_ft is not None
+                and dist_ft > weapon.range_increment_ft
+            ):
+                base_ac = full_ac_base
+            elif denies_dex:
+                base_ac = (
+                    target.combatant.ac.touch - max(0, target.combatant.abilities.dex_mod)
+                )
+            else:
+                base_ac = target.combatant.ac.touch
         else:
-            base_ac = target.combatant.ac.total
+            base_ac = full_ac_base
         ac = base_ac + resolve_modifiers(self._stat_modifiers(target, "ac"))
         occupied = frozenset(
             s.pos for s in self._states if s.active and s is not attacker and s is not target
@@ -697,7 +730,7 @@ class CombatEngine:
             self._grid,
             attacker.pos,
             target.pos,
-            ranged=weapon.kind == "ranged",
+            ranged=self._is_ranged_attack(weapon),
             occupied=occupied,
         ):
             ac += _COVER_AC_BONUS
@@ -900,11 +933,13 @@ class CombatEngine:
         )
 
     def _check_provoked_aoo(self, attacker: CombatantState, weapon: AttackSpec) -> bool:
-        """Check for ranged-AoO: firing a ranged weapon in a threatened square provokes.
+        """Check for ranged-AoO: firing a ranged-style weapon in a threatened square provokes.
 
+        Ranged-style means projectile weapons and touch thrown/fired weapons
+        (touch with a range increment); melee touch (no increment) does not provoke.
         Returns True if the attacker dropped (caller must stop attacking).
         """
-        if weapon.kind != "ranged":
+        if not self._is_ranged_attack(weapon):
             return False
         for enemy in self._enemies_threatening(attacker, attacker.pos):
             if self._aoo_used.get(enemy.combatant.id, 0) >= self._aoo_allowance(enemy):

src/pf1e_simulator/models.py

@@ -237,7 +237,9 @@ class AttackSpec(_FrozenModel):
 
     `count` captures repeated identical swings ("2x Talons") without listing
     the same entry twice. `reach_ft` applies to melee/touch kinds,
-    `range_increment_ft` to ranged/touch kinds.
+    `range_increment_ft` to ranged/touch kinds. `firearm` marks a ranged-touch
+    weapon (gun) whose shots resolve against touch AC within the first range
+    increment and against full AC beyond it.
     """
 
     id: str
@@ -251,6 +253,7 @@ class AttackSpec(_FrozenModel):
     reach_ft: int = 5
     range_increment_ft: int | None = None
     count: int = Field(default=1, ge=1)
+    firearm: bool = False
 
 
 class DamageReduction(_FrozenModel):