mtgodot-poc/project/pet_companion_system.gd

# pet_companion_system.gd —— Metin2 40250 伴随宠物封印召唤与战力注入系统 1:1
# 对照 40250 服务端 PetSystem.cpp, char_pet.cpp
class_name PetCompanionSystem
extends RefCounted

signal pet_summoned(pet_name: String, vnum: int)
signal pet_dismissed(pet_name: String)
signal pet_state_changed(state: String)

const PET_TABLE: Dictionary = {
	53001: {
		"name": "火凤凰",
		"mob_vnum": 34001,
		"bonuses": {"max_hp": 1500, "monster_dmg_pct": 15},
		"desc": "最大生命 +1500，对怪物伤害提升 15%"
	},
	53002: {
		"name": "幼鹿",
		"mob_vnum": 34002,
		"bonuses": {"max_hp": 1000, "exp_pct": 15},
		"desc": "最大生命 +1000，获得经验值增加 15%"
	},
	53003: {
		"name": "冰凤凰",
		"mob_vnum": 34003,
		"bonuses": {"max_hp": 1500, "def_pct": 15},
		"desc": "最大生命 +1500，物理防御提升 15%"
	},
	53005: {
		"name": "小胖熊猫",
		"mob_vnum": 34005,
		"bonuses": {"max_hp": 1000, "critical_pct": 15},
		"desc": "最大生命 +1000，致命一击几率提升 15%"
	},
	53006: {
		"name": "幼狮",
		"mob_vnum": 34006,
		"bonuses": {"max_hp": 1500, "att_pct": 10},
		"desc": "最大生命 +1500，物理攻击力提升 10%"
	}
}

const FOLLOW_STOP_DIST := 2.0   # 停止距离
const FOLLOW_RUN_DIST := 3.5    # 开始跟随奔跑距离
const TELEPORT_DIST := 25.0     # 瞬间拉回距离
const PET_MOVE_SPEED := 4.5     # 移动速度 (m/s)

var is_summoned: bool = false
var current_seal_vnum: int = 0
var active_pet: Dictionary = {}
var pet_position: Vector3 = Vector3.ZERO
var pet_state: String = "wait" # "wait" 或 "run"
var remaining_time: float = 0.0

# 召唤 / 收回宠物 (右键点击宠物封印石)
func toggle_pet_seal(seal_item: Dictionary, player_pos: Vector3) -> Dictionary:
	var vnum: int = int(seal_item.get("vnum", 0))
	if not PET_TABLE.has(vnum):
		return {"ok": false, "reason": "NOT_A_PET_SEAL", "msg": "这不是有效的宠物封印！"}

	# 若当前已召唤同一只宠物，则收回
	if is_summoned and current_seal_vnum == vnum:
		var pet_name = active_pet.get("name", "宠物")
		dismiss_pet()
		return {
			"ok": true,
			"action": "dismiss",
			"pet_name": pet_name,
			"msg": "已将【%s】收回封印石。" % pet_name
		}

	# 若当前召唤了不同宠物，先收回
	if is_summoned:
		dismiss_pet()

	# 召唤新宠物
	var cfg: Dictionary = PET_TABLE[vnum]
	current_seal_vnum = vnum
	is_summoned = true
	remaining_time = float(seal_item.get("duration", 86400.0)) # 默认 24 小时
	pet_position = player_pos + Vector3(-1.5, 0.0, -1.5)
	pet_state = "wait"

	active_pet = {
		"vnum": vnum,
		"name": cfg["name"],
		"mob_vnum": cfg["mob_vnum"],
		"bonuses": cfg["bonuses"].duplicate()
	}

	pet_summoned.emit(cfg["name"], vnum)

	return {
		"ok": true,
		"action": "summon",
		"pet_name": cfg["name"],
		"bonuses": cfg["bonuses"],
		"msg": "伴随宠物【%s】已召唤出战！" % cfg["name"]
	}

# 收回当前宠物
func dismiss_pet() -> void:
	if not is_summoned:
		return

	var pname = active_pet.get("name", "")
	is_summoned = false
	current_seal_vnum = 0
	active_pet.clear()
	pet_state = "wait"

	pet_dismissed.emit(pname)

# 获取当前宠物注入的战力属性
func get_active_bonuses() -> Dictionary:
	if not is_summoned:
		return {}
	return active_pet.get("bonuses", {}).duplicate()

# 3D 伴随移动逻辑
func update_movement(player_pos: Vector3, dt: float) -> void:
	if not is_summoned:
		return

	var dist: float = pet_position.distance_to(player_pos)

	# 超远距离瞬间传回身边
	if dist >= TELEPORT_DIST:
		pet_position = player_pos + Vector3(-1.5, 0.0, -1.5)
		pet_state = "wait"
		pet_state_changed.emit("wait")
		return

	# 跟随靠近
	if dist > FOLLOW_STOP_DIST:
		var dir := (player_pos - pet_position).normalized()
		pet_position += dir * PET_MOVE_SPEED * dt
		if pet_state != "run":
			pet_state = "run"
			pet_state_changed.emit("run")
	else:
		if pet_state != "wait":
			pet_state = "wait"
			pet_state_changed.emit("wait")

# 逐帧倒计时衰减
func update(dt: float) -> void:
	if not is_summoned:
		return

	remaining_time -= dt
	if remaining_time <= 0.0:
		dismiss_pet()