# mercenary_companion_system.gd —— Metin2 40250 离线单机假人/陪练佣兵助战系统 1:1
# 对照 40250 服务端 char_companion.cpp, party.cpp, affect.h
class_name MercenaryCompanionSystem
extends RefCounted

signal mercenary_summoned(merc_id: int, name: String)
signal mercenary_dismissed()
signal buff_applied_to_player(buff_name: String, duration: float, value: float)
signal heal_applied_to_player(heal_amount: int)
signal mercenary_attacked(target_id: String, damage: int)
signal mercenary_downed()
signal mercenary_revived()

enum MercenaryType {
	SHAMAN_HEALER = 1, # 龙神萨满·苏菲 (辅助/治疗)
	WARRIOR_TANK = 2   # 近卫战狂·阿雷斯 (肉盾/前锋)
}

enum Stance {
	FOLLOW = 0, # 被动跟随
	ASSIST = 1, # 协同攻击
	STAY = 2    # 原地待命
}

const REVIVE_COOLDOWN: float = 60.0 # 死亡自动复活冷却 (秒)
const TELEPORT_DISTANCE: float = 25.0 # 超出此距离瞬间传送归队
const HEAL_COOLDOWN: float = 10.0 # 治疗术内置冷却
const BUFF_COOLDOWN: float = 30.0 # Buff 持续与刷新周期

const MERCENARY_DATA: Dictionary = {
	MercenaryType.SHAMAN_HEALER: {
		"name": "龙神萨满·苏菲",
		"job": 3,
		"base_hp": 8000,
		"base_sp": 6000,
		"atk": 350,
		"def": 280,
		"buffs": [
			{"name": "巨龙之赐", "type": "def_bonus", "value": 0.20, "duration": 120.0},
			{"name": "龙之协助", "type": "crit_bonus", "value": 0.15, "duration": 120.0}
		]
	},
	MercenaryType.WARRIOR_TANK: {
		"name": "近卫战狂·阿雷斯",
		"job": 0,
		"base_hp": 15000,
		"base_sp": 2000,
		"atk": 650,
		"def": 500,
		"buffs": [
			{"name": "强身战气", "type": "atk_bonus", "value": 0.15, "duration": 120.0},
			{"name": "狂暴姿态", "type": "speed_bonus", "value": 0.20, "duration": 120.0}
		]
	}
}

var active_type: int = 0
var merc_name: String = ""
var level: int = 1
var max_hp: int = 1000
var current_hp: int = 1000
var max_sp: int = 500
var current_sp: int = 500
var atk: int = 200
var def: int = 150
var is_active: bool = false
var is_alive: bool = false
var current_stance: int = Stance.ASSIST
var pos: Vector3 = Vector3.ZERO

# 计时器
var heal_timer: float = 0.0
var buff_timer: float = 0.0
var revive_timer: float = 0.0

# 召唤指定佣兵
func summon_mercenary(merc_type: int, player_pos: Vector3, player_level: int = 50) -> Dictionary:
	if not MERCENARY_DATA.has(merc_type):
		return {"ok": false, "reason": "INVALID_MERC_TYPE", "msg": "未知的佣兵类型！"}

	var cfg = MERCENARY_DATA[merc_type]
	active_type = merc_type
	merc_name = cfg["name"]
	level = player_level

	# 等级动态成长数值
	var growth_mult = 1.0 + float(level - 1) * 0.05
	max_hp = int(float(cfg["base_hp"]) * growth_mult)
	current_hp = max_hp
	max_sp = int(float(cfg["base_sp"]) * growth_mult)
	current_sp = max_sp
	atk = int(float(cfg["atk"]) * growth_mult)
	def = int(float(cfg["def"]) * growth_mult)

	is_active = true
	is_alive = true
	current_stance = Stance.ASSIST
	pos = player_pos + Vector3(-2.0, 0.0, -2.0)

	heal_timer = 0.0
	buff_timer = 0.0
	revive_timer = 0.0

	mercenary_summoned.emit(active_type, merc_name)

	return {
		"ok": true,
		"type": active_type,
		"name": merc_name,
		"level": level,
		"hp": current_hp,
		"atk": atk,
		"def": def,
		"pos": pos,
		"msg": "佣兵【%s】应召前来助战！" % merc_name
	}

# 解散佣兵
func dismiss_mercenary() -> Dictionary:
	if not is_active:
		return {"ok": false, "reason": "NOT_SUMMONED"}

	is_active = false
	is_alive = false
	active_type = 0
	mercenary_dismissed.emit()
	return {"ok": true, "msg": "佣兵已暂时离队归营。"}

# 切换战术姿态
func set_stance(stance: int) -> Dictionary:
	if not is_active:
		return {"ok": false, "reason": "NOT_SUMMONED"}
	current_stance = stance
	return {"ok": true, "stance": current_stance}

# 帧心跳更新 AI 与协同战斗
func update_mercenary(delta: float, player_pos: Vector3, player_hp: int, player_max_hp: int, target_id: String = "", target_pos: Vector3 = Vector3.ZERO) -> Dictionary:
	if not is_active:
		return {"status": "inactive"}

	# 死亡复活倒计时
	if not is_alive:
		revive_timer -= delta
		if revive_timer <= 0.0:
			revive()
			return {"status": "just_revived"}
		return {"status": "downed", "remaining_revive": revive_timer}

	# 计时器更新
	if heal_timer > 0.0:
		heal_timer = max(0.0, heal_timer - delta)
	if buff_timer > 0.0:
		buff_timer = max(0.0, buff_timer - delta)

	# 1. 距离过远瞬移归队
	var dist_to_player = pos.distance_to(player_pos)
	if dist_to_player > TELEPORT_DISTANCE:
		pos = player_pos + Vector3(-1.5, 0.0, -1.5)
		return {"status": "teleported_to_player"}

	# 2. 萨满智能辅助：给玩家刷新 Buff
	if buff_timer <= 0.0:
		buff_timer = BUFF_COOLDOWN
		_apply_buffs_to_player()

	# 3. 萨满智能救死扶伤：当玩家 HP < 60% 触发急救
	if active_type == MercenaryType.SHAMAN_HEALER and heal_timer <= 0.0:
		var hp_ratio = float(player_hp) / float(max(1, player_max_hp))
		if hp_ratio < 0.60:
			heal_timer = HEAL_COOLDOWN
			var heal_amt = int(float(player_max_hp) * 0.35)
			heal_applied_to_player.emit(heal_amt)
			return {
				"status": "cast_heal",
				"heal_amount": heal_amt,
				"msg": "【%s】吟唱巨龙圣歌，为你恢复了 %d 点生命值！" % [merc_name, heal_amt]
			}

	# 4. 战术行为分流
	match current_stance:
		Stance.STAY:
			return {"status": "staying"}

		Stance.FOLLOW:
			# 保持紧随玩家身后 2.5 米
			if dist_to_player > 3.0:
				pos = pos.move_toward(player_pos, 5.0 * delta)
				return {"status": "following", "dist": dist_to_player}
			return {"status": "standing_by"}

		Stance.ASSIST:
			# 优先跟随；若有目标则协同集火
			if not target_id.is_empty():
				var dist_to_tgt = pos.distance_to(target_pos)
				var desired_range = 10.0 if active_type == MercenaryType.SHAMAN_HEALER else 2.5
				if dist_to_tgt > desired_range:
					pos = pos.move_toward(target_pos, 5.5 * delta)
					return {"status": "closing_in_target", "target": target_id}
				else:
					# 施展协同攻击
					var dmg = atk
					mercenary_attacked.emit(target_id, dmg)
					return {
						"status": "attacked_target",
						"target": target_id,
						"damage": dmg
					}
			else:
				if dist_to_player > 3.0:
					pos = pos.move_toward(player_pos, 5.0 * delta)
				return {"status": "following_idle"}

	return {"status": "idle"}

# 给主人施加专属辅助光环
func _apply_buffs_to_player() -> void:
	var cfg = MERCENARY_DATA.get(active_type, {})
	var buffs: Array = cfg.get("buffs", [])
	for b in buffs:
		buff_applied_to_player.emit(b["name"], b["duration"], b["value"])

# 佣兵受到伤害
func receive_damage(raw_dmg: int) -> Dictionary:
	if not is_active or not is_alive:
		return {"ok": false}

	var net_dmg = max(1, raw_dmg - def)
	current_hp = max(0, current_hp - net_dmg)

	if current_hp <= 0:
		is_alive = false
		revive_timer = REVIVE_COOLDOWN
		mercenary_downed.emit()
		return {
			"ok": true,
			"downed": true,
			"msg": "佣兵【%s】力竭倒下！将在 60 秒后恢复伤势复活。" % merc_name
		}

	return {
		"ok": true,
		"downed": false,
		"remaining_hp": current_hp,
		"net_dmg": net_dmg
	}

# 复活佣兵
func revive(instant: bool = false) -> Dictionary:
	if not is_active:
		return {"ok": false, "reason": "NOT_SUMMONED"}

	is_alive = true
	current_hp = int(float(max_hp) * (1.0 if instant else 0.5))
	revive_timer = 0.0
	mercenary_revived.emit()
	return {
		"ok": true,
		"hp": current_hp,
		"msg": "佣兵【%s】重新站起投入战斗！" % merc_name
	}

# 获取当前佣兵状态
func get_mercenary_info() -> Dictionary:
	return {
		"is_active": is_active,
		"is_alive": is_alive,
		"type": active_type,
		"name": merc_name,
		"level": level,
		"current_hp": current_hp,
		"max_hp": max_hp,
		"current_sp": current_sp,
		"max_sp": max_sp,
		"atk": atk,
		"def": def,
		"stance": current_stance,
		"pos": pos,
		"revive_timer": revive_timer
	}