mtgodot-poc/project/horse_combat_system.gd

# horse_combat_system.gd —— Metin2 40250 战马骑乘战斗与 4 大战马专属技能 1:1
# 对照 40250 服务端 char_skill.cpp, char_horse.cpp, skilldesc.txt:137-140
class_name HorseCombatSystem
extends RefCounted

signal horse_attack_performed(target_count: int, total_dmg: int)
signal horse_skill_used(skill_id: int, skill_name: String, cost_sp: int)
signal horse_stamina_changed(current: float, max_val: float)

const HORSE_TIER_BEGINNER := 1 # 初级马 (Lv 1-10, 仅代步)
const HORSE_TIER_COMBAT := 2   # 战斗马 (Lv 11-20, 可马上挥砍)
const HORSE_TIER_MILITARY := 3 # 军马 (Lv 21-30, 可马上挥砍并施展 4 大马术技能)

const MOUNTED_ATTACK_RANGE := 5.0
const FOOT_ATTACK_RANGE := 3.0

const ITEM_FOOD_CARROT := 50054  # 胡萝卜 (战斗马饲料)
const ITEM_FOOD_GINSENG := 50058 # 人参 (军马饲料)

const HORSE_SKILLS: Dictionary = {
	137: {
		"name": "战马砍击",
		"sp_cost": 30,
		"cooldown": 15.0,
		"dmg_mult": 2.5,
		"effect": "KNOCKBACK",
		"range": 5.0
	},
	138: {
		"name": "战马突刺",
		"sp_cost": 35,
		"cooldown": 20.0,
		"dmg_mult": 2.0,
		"effect": "STUMBLE",
		"range": 8.0
	},
	139: {
		"name": "战马震击",
		"sp_cost": 40,
		"cooldown": 25.0,
		"dmg_mult": 3.0,
		"effect": "AOE_STUN",
		"range": 6.0
	},
	140: {
		"name": "破浪击",
		"sp_cost": 30,
		"cooldown": 12.0,
		"dmg_mult": 2.2,
		"effect": "RANGED_WAVE",
		"range": 12.0
	}
}

var is_riding: bool = false
var horse_tier: int = HORSE_TIER_NONE
var horse_stamina: float = 100.0
var max_stamina: float = 100.0
var skill_cooldowns: Dictionary = {
	137: 0.0,
	138: 0.0,
	139: 0.0,
	140: 0.0
}

const HORSE_TIER_NONE := 0

# 设置骑乘状态
func set_mounted_state(riding: bool, tier: int = HORSE_TIER_MILITARY) -> void:
	is_riding = riding
	horse_tier = tier if riding else HORSE_TIER_NONE

# 马上普通挥砍攻击 (Mounted Basic Sweep Attack)
func perform_mounted_basic_attack(
	base_att: int,
	targets_in_range: Array
) -> Dictionary:
	if not is_riding:
		return {"ok": false, "reason": "NOT_RIDING", "msg": "未处于骑乘状态！"}

	if horse_tier < HORSE_TIER_COMBAT:
		return {"ok": false, "reason": "HORSE_TIER_TOO_LOW", "msg": "当前马匹等级不足，无法在马上战斗！需要战斗马或军马。"}

	# 精力衰减
	horse_stamina = maxf(0.0, horse_stamina - 0.5)
	horse_stamina_changed.emit(horse_stamina, max_stamina)

	# 伤害计算：马上横扫增伤 1.2x (精力枯竭时惩罚为 0.8x)
	var mult: float = 1.2 if horse_stamina > 0.0 else 0.8
	var dmg_per_target := int(base_att * mult)
	var total_dmg: int = 0
	var hit_targets: Array = []

	for target in targets_in_range:
		var dist: float = float(target.get("distance", 999.0))
		if dist <= MOUNTED_ATTACK_RANGE:
			hit_targets.append(target)
			total_dmg += dmg_per_target

	horse_attack_performed.emit(hit_targets.size(), total_dmg)

	return {
		"ok": true,
		"attack_range": MOUNTED_ATTACK_RANGE,
		"hit_count": hit_targets.size(),
		"damage_per_hit": dmg_per_target,
		"total_damage": total_dmg,
		"stamina": horse_stamina
	}

# 施展 4 大战马专属技能 (137, 138, 139, 140)
func use_horse_skill(
	skill_id: int,
	player_sp: int,
	base_att: int
) -> Dictionary:
	if not is_riding:
		return {"ok": false, "reason": "NOT_RIDING", "msg": "未在马背上，无法施展马术技能！"}

	if horse_tier < HORSE_TIER_MILITARY:
		return {"ok": false, "reason": "REQUIRES_MILITARY_HORSE", "msg": "马术专属技能需要军马 (Lv21+) 方可施展！"}

	if not HORSE_SKILLS.has(skill_id):
		return {"ok": false, "reason": "INVALID_SKILL_ID", "msg": "未知的战马技能！"}

	var cfg: Dictionary = HORSE_SKILLS[skill_id]

	# 检查冷却
	if skill_cooldowns[skill_id] > 0.0:
		return {
			"ok": false,
			"reason": "SKILL_ON_COOLDOWN",
			"remaining_cd": skill_cooldowns[skill_id],
			"msg": "技能【%s】冷却中，剩余 %.1f 秒。" % [cfg["name"], skill_cooldowns[skill_id]]
		}

	# 检查玩家法力 (SP)
	var sp_cost: int = cfg["sp_cost"]
	if player_sp < sp_cost:
		return {
			"ok": false,
			"reason": "INSUFFICIENT_SP",
			"cost": sp_cost,
			"current_sp": player_sp,
			"msg": "法力值不足，无法施展【%s】！" % cfg["name"]
		}

	# 检查马匹精力
	if horse_stamina < 5.0:
		return {
			"ok": false,
			"reason": "HORSE_EXHAUSTED",
			"msg": "战马体力已透支，请先喂食胡萝卜或人参！"
		}

	# 施法成功：扣除精力、进入冷却
	horse_stamina = maxf(0.0, horse_stamina - 5.0)
	skill_cooldowns[skill_id] = cfg["cooldown"]
	horse_stamina_changed.emit(horse_stamina, max_stamina)
	horse_skill_used.emit(skill_id, cfg["name"], sp_cost)

	var dealt_dmg := int(base_att * cfg["dmg_mult"])

	return {
		"ok": true,
		"skill_id": skill_id,
		"skill_name": cfg["name"],
		"sp_cost": sp_cost,
		"cooldown": cfg["cooldown"],
		"damage": dealt_dmg,
		"effect": cfg["effect"],
		"range": cfg["range"],
		"msg": "施展了战马技能【%s】！" % cfg["name"]
	}

# 喂食恢复马匹精力 (胡萝卜 +40, 人参 +80)
func feed_horse(food_vnum: int) -> Dictionary:
	if horse_tier == HORSE_TIER_NONE:
		return {"ok": false, "reason": "NO_HORSE", "msg": "当前没有马匹！"}

	var restore_amount := 0.0
	var food_name := ""
	if food_vnum == ITEM_FOOD_CARROT:
		restore_amount = 40.0
		food_name = "胡萝卜"
	elif food_vnum == ITEM_FOOD_GINSENG:
		restore_amount = 80.0
		food_name = "人参"
	else:
		return {"ok": false, "reason": "WRONG_FOOD", "msg": "这不是战马适合的食物！"}

	horse_stamina = minf(max_stamina, horse_stamina + restore_amount)
	horse_stamina_changed.emit(horse_stamina, max_stamina)

	return {
		"ok": true,
		"food_name": food_name,
		"restored": restore_amount,
		"current_stamina": horse_stamina,
		"msg": "战马食用了【%s】，恢复了体力！" % food_name
	}

# 冷却逐帧更新
func update(dt: float) -> void:
	for sk in skill_cooldowns.keys():
		if skill_cooldowns[sk] > 0.0:
			skill_cooldowns[sk] = maxf(0.0, skill_cooldowns[sk] - dt)