# energy_system.gd —— Metin2 40250 官方能量碎片提取与能量水晶熔炼系统 1:1
# 对照 40250 服务端 energy_system.quest, char_item.cpp:6319 (CBuffOnAttributes), char.h (POINT_ENERGY=128)
class_name EnergySystem
extends RefCounted

signal fragments_extracted(count: int, item_name: String)
signal crystal_fused(crystal_item: Dictionary)
signal energy_activated(duration: float, bonus_pct: int)
signal energy_expired()

const NPC_ALCHEMIST := 20001 # 炼金术士
const MIN_PLAYER_LEVEL := 35 # 角色开启门槛 35 级
const MIN_EQUIP_LEVEL  := 35 # 装备分解门槛 35 级

const VNUM_ENERGY_STONE   := 51001 # 能量碎片 (Energy Stone / Fragment)
const VNUM_CHARGING_STONE := 51002 # 能量水晶 (Charging Stone / Energy Crystal)

const FUSION_NEED_STONES := 30   # 熔炼需要 30 颗碎片
const FUSION_COST_GOLD   := 1000 # 熔炼手续费 1000 金币
const ENERGY_DURATION    := 7200.0 # 2 小时 (7200 秒)
const ATTR_BONUS_PCT     := 10     # 全身穿戴装备属性增幅 +10%

var is_energy_active: bool = false
var energy_time_remaining: float = 0.0
var applied_bonuses: Dictionary = {}

# 计算装备分解产出碎片数量 (40250 energy_system.quest 概率阶梯)
static func calculate_fragment_yield(equip_level_limit: int, rand_val: int = -1) -> int:
	var r: int = rand_val if rand_val >= 0 else (randi() % 100)
	if equip_level_limit >= 35 and equip_level_limit <= 50:
		# 35~50 级装备产出 1~5 颗
		return clampi(1 + (r % 5), 1, 5)
	elif equip_level_limit > 50 and equip_level_limit <= 70:
		# 51~70 级装备产出 3~8 颗
		return clampi(3 + (r % 6), 3, 8)
	else:
		# 70 级以上顶级装备产出 5~15 颗
		return clampi(5 + (r % 11), 5, 15)

# 在炼金术士处分解淘汰装备提取能量碎片
func extract_energy_fragments(inventory: Array, slot_index: int, player_level: int) -> Dictionary:
	if player_level < MIN_PLAYER_LEVEL:
		return {"ok": false, "reason": "PLAYER_LEVEL_TOO_LOW", "msg": "炼金术士只为 35 级以上的强者提取能量！"}
	
	if slot_index < 0 or slot_index >= inventory.size() or inventory[slot_index] == null:
		return {"ok": false, "reason": "INVALID_SLOT"}
	
	var item: Dictionary = inventory[slot_index]
	var limit_lv := int(item.get("level_limit", item.get("limit_level", 0)))
	if limit_lv < MIN_EQUIP_LEVEL:
		return {"ok": false, "reason": "EQUIP_LEVEL_TOO_LOW", "msg": "只能分解 35 级以上的武器、防具或首饰！"}
	
	# 检查箭矢等消耗品
	if item.get("type", 0) == 1 and item.get("subtype", 0) == 5: # WEAPON_ARROW
		return {"ok": false, "reason": "ARROW_NOT_ALLOWED", "msg": "箭矢无法提取能量！"}
	
	var item_name: String = str(item.get("name", "淘汰装备"))
	var count_yield := calculate_fragment_yield(limit_lv)
	
	# 移除装备
	inventory[slot_index] = null
	
	# 发放能量碎片 (查找已有堆叠或找空位)
	var placed := false
	for i in range(inventory.size()):
		if inventory[i] != null and int(inventory[i].get("vnum", 0)) == VNUM_ENERGY_STONE:
			var cur_c := int(inventory[i].get("count", 1))
			inventory[i]["count"] = cur_c + count_yield
			placed = true
			break
	
	if not placed:
		for i in range(inventory.size()):
			if inventory[i] == null:
				inventory[i] = {
					"vnum": VNUM_ENERGY_STONE,
					"name": "能量碎片",
					"count": count_yield
				}
				placed = true
				break
	
	fragments_extracted.emit(count_yield, item_name)
	
	return {
		"ok": true,
		"yield": count_yield,
		"item_name": item_name,
		"msg": "成功分解【%s】，提取出 %d 颗【能量碎片】！" % [item_name, count_yield]
	}

# 熔炼能量水晶 (30 碎片 + 1000 金币)
func fuse_energy_crystal(inventory: Array, player_gold: Dictionary) -> Dictionary:
	var cur_gold := int(player_gold.get("gold", 0))
	if cur_gold < FUSION_COST_GOLD:
		return {"ok": false, "reason": "NOT_ENOUGH_GOLD", "msg": "金币不足！熔炼需要 1,000 金币。"}
	
	# 统计能量碎片总数
	var total_stones := 0
	var stone_slots: Array = []
	for i in range(inventory.size()):
		if inventory[i] != null and int(inventory[i].get("vnum", 0)) == VNUM_ENERGY_STONE:
			total_stones += int(inventory[i].get("count", 1))
			stone_slots.append(i)
	
	if total_stones < FUSION_NEED_STONES:
		return {
			"ok": false,
			"reason": "NOT_ENOUGH_STONES",
			"msg": "能量碎片不足！需要 %d 颗，当前拥有 %d 颗。" % [FUSION_NEED_STONES, total_stones]
		}
	
	# 寻找放置能量水晶的槽位
	var crystal_slot := -1
	for i in range(inventory.size()):
		if inventory[i] == null:
			crystal_slot = i
			break
	
	# 扣除 30 颗碎片
	var need_to_deduct := FUSION_NEED_STONES
	for slot_idx in stone_slots:
		var it: Dictionary = inventory[slot_idx]
		var c := int(it.get("count", 1))
		if c <= need_to_deduct:
			need_to_deduct -= c
			inventory[slot_idx] = null
			if crystal_slot == -1:
				crystal_slot = slot_idx # 复用清空的格子
		else:
			it["count"] = c - need_to_deduct
			need_to_deduct = 0
			break
	
	player_gold["gold"] = cur_gold - FUSION_COST_GOLD
	
	var crystal := {
		"vnum": VNUM_CHARGING_STONE,
		"name": "能量水晶",
		"count": 1
	}
	inventory[crystal_slot] = crystal
	
	crystal_fused.emit(crystal)
	
	return {
		"ok": true,
		"crystal": crystal,
		"slot": crystal_slot,
		"msg": "熔炼成功！纯净的【能量水晶】已凝聚成型。"
	}

# 使用能量水晶激活 2 小时全身穿戴装备 10% 增幅 (40250 CBuffOnAttributes)
func use_energy_crystal(inventory: Array, slot_index: int, equipped_items: Array, player_stats: Dictionary) -> Dictionary:
	if slot_index < 0 or slot_index >= inventory.size() or inventory[slot_index] == null:
		return {"ok": false, "reason": "INVALID_SLOT"}
	
	var item: Dictionary = inventory[slot_index]
	if int(item.get("vnum", 0)) != VNUM_CHARGING_STONE:
		return {"ok": false, "reason": "NOT_A_CHARGING_STONE", "msg": "此物品不是能量水晶！"}
	
	# 消耗 1 颗能量水晶
	var c := int(item.get("count", 1))
	if c > 1:
		item["count"] = c - 1
	else:
		inventory[slot_index] = null
	
	# 如果已激活，先清除旧加成
	if is_energy_active:
		_clear_energy_buffs(player_stats)
	
	# 计算穿戴装备基础属性总和的 10%
	applied_bonuses.clear()
	for eq in equipped_items:
		if eq == null:
			continue
		var atk = int(eq.get("attack_power", 0))
		var def = int(eq.get("defense", 0))
		var hp  = int(eq.get("max_hp", 0))
		if atk > 0:
			applied_bonuses["attack_power"] = int(applied_bonuses.get("attack_power", 0)) + int(ceil(atk * 0.10))
		if def > 0:
			applied_bonuses["defense"] = int(applied_bonuses.get("defense", 0)) + int(ceil(def * 0.10))
		if hp > 0:
			applied_bonuses["max_hp"] = int(applied_bonuses.get("max_hp", 0)) + int(ceil(hp * 0.10))
	
	# 保底全属性增益 (即使没有极品装备，也提供保底加成)
	applied_bonuses["attack_power"] = maxi(10, int(applied_bonuses.get("attack_power", 0)))
	applied_bonuses["defense"] = maxi(10, int(applied_bonuses.get("defense", 0)))
	
	# 注入玩家属性
	for k in applied_bonuses.keys():
		player_stats[k] = int(player_stats.get(k, 0)) + applied_bonuses[k]
	
	is_energy_active = true
	energy_time_remaining = ENERGY_DURATION
	
	energy_activated.emit(ENERGY_DURATION, ATTR_BONUS_PCT)
	
	return {
		"ok": true,
		"duration": ENERGY_DURATION,
		"bonuses": applied_bonuses,
		"msg": "能量水晶激活！全身装备属性增幅 +10%%，持续 2 小时。"
	}

# 清除能量属性
func _clear_energy_buffs(player_stats: Dictionary) -> void:
	for k in applied_bonuses.keys():
		player_stats[k] = int(player_stats.get(k, 0)) - applied_bonuses[k]
	applied_bonuses.clear()
	is_energy_active = false
	energy_time_remaining = 0.0

# 时钟心跳推进
func update(delta: float, player_stats: Dictionary) -> void:
	if not is_energy_active:
		return
	energy_time_remaining -= delta
	if energy_time_remaining <= 0.0:
		_clear_energy_buffs(player_stats)
		energy_expired.emit()

# 序列化
func serialize() -> Dictionary:
	return {
		"is_energy_active": is_energy_active,
		"energy_time_remaining": energy_time_remaining,
		"applied_bonuses": applied_bonuses.duplicate(true)
	}

# 反序列化
func deserialize(data: Dictionary) -> void:
	is_energy_active = bool(data.get("is_energy_active", false))
	energy_time_remaining = float(data.get("energy_time_remaining", 0.0))
	applied_bonuses = data.get("applied_bonuses", {}).duplicate(true)