Add weapon move-type effectiveness

scripts/core/battle_state.gd

@@ -708,16 +708,19 @@ func get_damage_preview(attacker_id: String, target_id: String) -> Dictionary:
 		return {}
 
 	var attack_locked := _unit_has_action_lock(attacker, "attack")
+	var effective_bonus := 0 if attack_locked else _weapon_effectiveness_bonus(attacker, target)
 	var damage := 0 if attack_locked else calculate_damage(attacker, target)
 	var target_hp_after: int = maxi(0, int(target["hp"]) - damage)
 	var counter_damage := 0
 	var attacker_hp_after := int(attacker["hp"])
 	var hit_chance := 0 if attack_locked else calculate_hit_chance(attacker, target)
 	var counter_hit_chance := 0
+	var counter_effective_bonus := 0
 	var counter_in_range := false
 	if not attack_locked and (target_hp_after > 0 or hit_chance < 100):
 		counter_in_range = _is_in_attack_range(target, attacker["pos"])
 		if counter_in_range:
+			counter_effective_bonus = _weapon_effectiveness_bonus(target, attacker)
 			counter_damage = calculate_damage(target, attacker)
 			counter_hit_chance = calculate_hit_chance(target, attacker)
 			attacker_hp_after = maxi(0, int(attacker["hp"]) - counter_damage)
@@ -725,6 +728,8 @@ func get_damage_preview(attacker_id: String, target_id: String) -> Dictionary:
 		"attacker_id": attacker_id,
 		"target_id": target_id,
 		"damage": damage,
+		"effective_bonus": effective_bonus,
+		"effective_target_type": _weapon_effectiveness_target_type(target) if effective_bonus > 0 else "",
 		"hit_chance": hit_chance,
 		"target_hp_after": target_hp_after,
 		"would_defeat": int(target["hp"]) - damage <= 0,
@@ -732,6 +737,8 @@ func get_damage_preview(attacker_id: String, target_id: String) -> Dictionary:
 		"attack_locked": attack_locked,
 		"counter_in_range": counter_in_range,
 		"counter_damage": counter_damage,
+		"counter_effective_bonus": counter_effective_bonus,
+		"counter_effective_target_type": _weapon_effectiveness_target_type(attacker) if counter_effective_bonus > 0 else "",
 		"counter_hit_chance": counter_hit_chance,
 		"attacker_hp_after": attacker_hp_after,
 		"counter_would_defeat": attacker_hp_after <= 0
@@ -828,7 +835,8 @@ func get_item_preview(user_id: String, item_id: String, target_cell: Vector2i) -
 
 func calculate_damage(attacker: Dictionary, target: Dictionary) -> int:
 	var terrain_defense := get_terrain_defense(target["pos"])
-	return max(1, _effective_stat(attacker, "atk") - _effective_stat(target, "def") - terrain_defense)
+	var effective_bonus := _weapon_effectiveness_bonus(attacker, target)
+	return max(1, _effective_stat(attacker, "atk") + effective_bonus - _effective_stat(target, "def") - terrain_defense)
 
 
 func calculate_hit_chance(attacker: Dictionary, target: Dictionary) -> int:
@@ -851,6 +859,49 @@ func calculate_skill_heal(caster: Dictionary, target: Dictionary, skill: Diction
 	return max(0, min(raw_heal, missing_hp))
 
 
+func _weapon_effectiveness_bonus(attacker: Dictionary, target: Dictionary) -> int:
+	var weapon := _equipped_weapon(attacker)
+	if weapon.is_empty():
+		return 0
+	if not _weapon_is_effective_against(weapon, target):
+		return 0
+	return max(0, int(weapon.get("effective_bonus_damage", 0)))
+
+
+func _weapon_is_effective_against(weapon: Dictionary, target: Dictionary) -> bool:
+	var target_move_type := _weapon_effectiveness_target_type(target)
+	if target_move_type.is_empty():
+		return false
+	var effective_types = weapon.get("effective_vs_move_types", [])
+	if typeof(effective_types) != TYPE_ARRAY:
+		return false
+	for move_type in effective_types:
+		if str(move_type) == target_move_type:
+			return true
+	return false
+
+
+func _weapon_effectiveness_target_type(target: Dictionary) -> String:
+	return str(target.get("move_type", "foot")).strip_edges()
+
+
+func _format_move_type(move_type: String) -> String:
+	return move_type.replace("_", " ").capitalize()
+
+
+func _equipped_weapon(unit: Dictionary) -> Dictionary:
+	var equipment = unit.get("equipment", {})
+	if typeof(equipment) != TYPE_DICTIONARY:
+		return {}
+	var weapon_id := str(equipment.get("weapon", ""))
+	if weapon_id.is_empty():
+		return {}
+	var weapon := get_item_def(weapon_id)
+	if str(weapon.get("kind", "")) != "weapon":
+		return {}
+	return weapon
+
+
 func get_status_effect_summary(unit_id: String) -> String:
 	var unit := get_unit(unit_id)
 	if unit.is_empty():
@@ -2630,7 +2681,11 @@ func _resolve_attack(attacker: Dictionary, target: Dictionary, is_counter := fal
 		return {"hit": false, "defeated": false}
 	var damage := calculate_damage(attacker, target)
 	target["hp"] = max(0, int(target["hp"]) - damage)
-	_emit_log("%s %s %s for %d damage. Hit %d%%." % [attacker["name"], verb, target["name"], damage, hit_chance])
+	var effective_bonus := _weapon_effectiveness_bonus(attacker, target)
+	var effective_text := ""
+	if effective_bonus > 0:
+		effective_text = " Effective +%d vs %s." % [effective_bonus, _format_move_type(_weapon_effectiveness_target_type(target))]
+	_emit_log("%s %s %s for %d damage. Hit %d%%.%s" % [attacker["name"], verb, target["name"], damage, hit_chance, effective_text])
 	_emit_combat_feedback(target, "-%d" % damage, "damage")
 
 	if int(target["hp"]) <= 0: