# mysterious_merchant_blackmarket_system.gd —— Metin2 40250 野外随机神秘游商与黑市折扣市场系统 1:1
# 对照 40250 服务端 shop.cpp, regen.cpp, char_item.cpp
class_name MysteriousMerchantBlackmarketSystem
extends RefCounted

signal merchant_appeared(map_name: String, pos: Vector2, duration_seconds: float)
signal merchant_departed()
signal item_bought(item_name: String, cost: int)
signal item_sold(item_name: String, earned: int)
signal stock_refreshed(stock_list: Array)

const NPC_VNUM := 20095 # 野外神秘游商 (Wandering Merchant)
const DEFAULT_DURATION := 1800.0 # 停留 30 分钟 (1800 秒)
const HIGH_PRICE_BUYBACK_MULTIPLIER := 1.3 # 高价回收 +30% 黄金溢价 (1.30x)
const ITEM_ANTIFLAG_SELL := 1 << 8 # 256 禁售标志位

# 3 大野外候选刷新点 (沙漠绿洲、雪山孤峰、烈焰核心)
const SPAWN_LOCATIONS: Array = [
	{"map": "Desert", "name": "沙漠绿洲", "pos": Vector2(120, 350)},
	{"map": "Mount_Sohan", "name": "雪山孤峰", "pos": Vector2(450, 680)},
	{"map": "Doyyumhwan", "name": "烈焰核心", "pos": Vector2(600, 210)}
]

# 黑市半价珍品底库预设 (40250 官方核心珍宝)
const DEFAULT_BLACK_MARKET_POOL: Array = [
	{
		"vnum": 51501,
		"name": "龙石炼金原石(巨龙之心)",
		"base_price": 2000000,
		"price": 1000000, # 5折半价
		"stock": 5,
		"count": 1,
		"type": 16 # ITEM_METIN / 炼金
	},
	{
		"vnum": 28430,
		"name": "+4 灵石礼包",
		"base_price": 5000000,
		"price": 2500000, # 5折半价
		"stock": 3,
		"count": 1,
		"type": 10 # ITEM_STONE
	},
	{
		"vnum": 50300,
		"name": "古代进阶技能秘籍",
		"base_price": 3000000,
		"price": 1500000, # 5折半价
		"stock": 3,
		"count": 1,
		"type": 17 # ITEM_SKILLBOOK
	},
	{
		"vnum": 25040,
		"name": "洗炼祝福包(双份)",
		"base_price": 1000000,
		"price": 500000, # 5折半价
		"stock": 10,
		"count": 2,
		"type": 3 # ITEM_USE
	},
	{
		"vnum": 71084,
		"name": "传说洗练神丹",
		"base_price": 4000000,
		"price": 2000000, # 5折半价
		"stock": 2,
		"count": 1,
		"type": 3 # ITEM_USE
	}
]

# 当前游商运行状态
var is_active: bool = false
var current_map: String = ""
var current_pos: Vector2 = Vector2.ZERO
var time_remaining: float = 0.0
var total_duration: float = DEFAULT_DURATION
var current_stock: Array = []

# 随机刷出野外神秘游商
func spawn_random_merchant(duration: float = DEFAULT_DURATION, loc_index: int = -1) -> Dictionary:
	var loc_idx: int = loc_index
	if loc_idx < 0 or loc_idx >= SPAWN_LOCATIONS.size():
		loc_idx = randi() % SPAWN_LOCATIONS.size()
	
	var chosen_loc: Dictionary = SPAWN_LOCATIONS[loc_idx]
	return spawn_merchant(chosen_loc["map"], chosen_loc["pos"], duration)

# 指定地点召唤/刷出游商
func spawn_merchant(map_name: String, pos: Vector2, duration: float = DEFAULT_DURATION) -> Dictionary:
	is_active = true
	current_map = map_name
	current_pos = pos
	time_remaining = duration
	total_duration = duration
	
	refresh_stock()
	
	merchant_appeared.emit(current_map, current_pos, duration)
	return {
		"ok": true,
		"map": current_map,
		"pos": current_pos,
		"duration": duration,
		"npc_vnum": NPC_VNUM
	}

# 游商离去或收摊
func despawn_merchant() -> void:
	if not is_active:
		return
	is_active = false
	current_map = ""
	current_pos = Vector2.ZERO
	time_remaining = 0.0
	current_stock.clear()
	merchant_departed.emit()

# 物理帧或逻辑心跳更新
func update(delta: float) -> void:
	if not is_active:
		return
	time_remaining -= delta
	if time_remaining <= 0.0:
		despawn_merchant()

# 重新生成黑市货架 (重置折扣和限量库存)
func refresh_stock() -> void:
	current_stock.clear()
	for item_template in DEFAULT_BLACK_MARKET_POOL:
		var good: Dictionary = item_template.duplicate(true)
		current_stock.append(good)
	stock_refreshed.emit(current_stock)

# 获取当前商品清单
func get_stock() -> Array:
	return current_stock.duplicate(true)

# 购买黑市商品
func buy_item(stock_idx: int, player_data: Dictionary, inventory: Array) -> Dictionary:
	if not is_active:
		return {"ok": false, "reason": "MERCHANT_NOT_ACTIVE", "msg": "神秘游商已离去或尚未现身！"}
	
	if stock_idx < 0 or stock_idx >= current_stock.size():
		return {"ok": false, "reason": "INVALID_STOCK_INDEX", "msg": "商品编号无效！"}
	
	var good: Dictionary = current_stock[stock_idx]
	var current_qty := int(good.get("stock", 0))
	if current_qty <= 0:
		return {"ok": false, "reason": "OUT_OF_STOCK", "msg": "该珍品黑市配额已售罄！"}
	
	var price := int(good.get("price", 0))
	var player_gold := int(player_data.get("gold", 0))
	if player_gold < price:
		return {"ok": false, "reason": "NOT_ENOUGH_GOLD", "msg": "金币不足，无法购买黑市珍品！"}
	
	# 寻找背包空槽
	var target_slot := -1
	for i in range(inventory.size()):
		if inventory[i] == null or (inventory[i] is Dictionary and inventory[i].is_empty()):
			target_slot = i
			break
	
	if target_slot == -1:
		return {"ok": false, "reason": "INVENTORY_FULL", "msg": "背包已满，请清理后再购买！"}
	
	# 扣费与发货
	player_data["gold"] = player_gold - price
	good["stock"] = current_qty - 1
	
	var bought_item: Dictionary = {
		"vnum": good["vnum"],
		"name": good["name"],
		"count": good.get("count", 1),
		"type": good.get("type", 0)
	}
	inventory[target_slot] = bought_item
	
	item_bought.emit(good["name"], price)
	
	return {
		"ok": true,
		"slot": target_slot,
		"item": bought_item,
		"cost": price,
		"remaining_stock": good["stock"],
		"msg": "成功以黑市特惠价购入 %s！" % good["name"]
	}

# 计算高价回收金额 (+30% 溢价)
func calculate_sell_price(item: Dictionary) -> int:
	var anti_flags := int(item.get("anti_flags", item.get("anti_flag", 0)))
	if anti_flags & ITEM_ANTIFLAG_SELL != 0:
		return 0 # 禁售品
	
	var base_price := int(item.get("shop_buy_price", item.get("gold", item.get("price", 1000))))
	var count := maxi(1, int(item.get("count", 1)))
	
	# 40250 官方标准回收价为买入价的 1/5 (20%)
	var standard_unit_sell: int = maxi(1, int(base_price / 5.0))
	
	# 神秘游商提供 +30% 溢价 (1.30 倍)
	var blackmarket_unit_sell: int = int(round(standard_unit_sell * HIGH_PRICE_BUYBACK_MULTIPLIER))
	
	return maxi(1, blackmarket_unit_sell * count)

# 向神秘游商高价出售闲置珍品
func sell_item(inv_slot: int, player_data: Dictionary, inventory: Array) -> Dictionary:
	if not is_active:
		return {"ok": false, "reason": "MERCHANT_NOT_ACTIVE", "msg": "神秘游商已离去，无法交易！"}
	
	if inv_slot < 0 or inv_slot >= inventory.size() or inventory[inv_slot] == null:
		return {"ok": false, "reason": "INVALID_SLOT", "msg": "背包槽位为空或无效！"}
	
	var item: Dictionary = inventory[inv_slot]
	var anti_flags := int(item.get("anti_flags", item.get("anti_flag", 0)))
	if anti_flags & ITEM_ANTIFLAG_SELL != 0:
		return {"ok": false, "reason": "ITEM_ANTIFLAG_SELL", "msg": "该物品属于非卖品，无法出售！"}
	
	var earn_gold := calculate_sell_price(item)
	if earn_gold <= 0:
		return {"ok": false, "reason": "VALUATION_ZERO", "msg": "该物品估价为 0，游商不予回收！"}
	
	var item_name: String = str(item.get("name", "珍宝"))
	
	# 结算金币与移除物品
	player_data["gold"] = int(player_data.get("gold", 0)) + earn_gold
	inventory[inv_slot] = null
	
	item_sold.emit(item_name, earn_gold)
	
	return {
		"ok": true,
		"earned": earn_gold,
		"item_name": item_name,
		"msg": "神秘游商高价收购了【%s】，支付了 %d 金币(+30%% 溢价)！" % [item_name, earn_gold]
	}

# 存档序列化
func serialize() -> Dictionary:
	return {
		"is_active": is_active,
		"current_map": current_map,
		"pos_x": current_pos.x,
		"pos_y": current_pos.y,
		"time_remaining": time_remaining,
		"total_duration": total_duration,
		"stock": current_stock.duplicate(true)
	}

# 读档反序列化
func deserialize(data: Dictionary) -> void:
	is_active = bool(data.get("is_active", false))
	current_map = str(data.get("current_map", ""))
	current_pos = Vector2(float(data.get("pos_x", 0.0)), float(data.get("pos_y", 0.0)))
	time_remaining = float(data.get("time_remaining", 0.0))
	total_duration = float(data.get("total_duration", DEFAULT_DURATION))
	current_stock = data.get("stock", []).duplicate(true)