# skill_book_system.gd —— 40250 技能书研读与技能突破进阶系统 1:1 规则引擎
# 严格对照：
#   metin2/src/server/game/src/char_item.cpp:2128-2160 (ITEM_SKILLBOOK / 50300)
#   metin2/src/server/game/src/char_skill.cpp:416-570  (CHARACTER::LearnSkillByBook)
#   metin2/src/server/game/src/char_item.cpp:1657      (Soul Stone 50513 / G->P)
#   ClientVS22/UserInterface/Packet.h
extends RefCounted

const SKILL_BOOK_VNUM := 50300
const EXORCISM_SCROLL_VNUM := 71001   # 驱魔卷轴 (AFFECT_SKILL_NO_BOOK_DELAY)
const HERMIT_ADVICE_VNUM := 71094     # 隐士教训 (AFFECT_SKILL_BOOK_BONUS)
const SOUL_STONE_VNUM := 71001        # 魂石 (50513)

const SKILL_BOOK_EXP_COST := 20000    # 40250 char_skill.cpp:430 need_exp = 20000
const SKILL_BOOK_DELAY := 86400       # 24 小时冷却 (LC_IsKorea 86400s)

# 40250 MasterType 枚举
const MASTER_NORMAL := 0              # Lv 1 - 20
const MASTER_M := 1                   # M1 - M10 (Lv 21 - 30)
const MASTER_G := 2                   # G1 - G10 (Lv 31 - 40)
const MASTER_P := 3                   # Perfect Master (Lv 40)

# 错误码
enum Result {
	SUCCESS_LEVEL_UP,     # 成功并升级（或突破到 G）
	SUCCESS_READ_ONCE,    # 成功研读一本（累积进度）
	FAIL_READ,            # 研读失败
	ERR_NOT_LEARNABLE,    # 非本职业/未入流派技能
	ERR_NOT_MASTER_TIER,  # 尚未达到 M 阶 (Lv < 20)
	ERR_ALREADY_G_OR_P,   # 已达到 G 阶或更高，无法再读技能书
	ERR_INSUFFICIENT_EXP, # 经验不足 20,000
	ERR_COOLDOWN,         # 24小时冷却中
}

# 魂石善恶值消耗表 (char_skill.cpp / training_grandmaster_skill.quest)
const SOUL_STONE_KARMA_COST := {
	1: 1000, 2: 1500, 3: 2000, 4: 2500, 5: 3000,
	6: 3500, 7: 4000, 8: 4500, 9: 5000, 10: 5500
}

# 判定技能书升级所需本数：40250 char_skill.cpp:509 need_bookcount = GetSkillLevel(dwSkillVnum) - 20
static func get_need_books(skill_level: int) -> int:
	# M1 (21) 需 1 本，M2 (22) 需 2 本 ... M10 (30) 需 10 本
	return maxi(1, skill_level - 20)

# 研读条件前置校验
static func check_can_read(
	skill_id: int,
	skill_level: int,
	master_type: int,
	player_exp: int,
	next_read_time: int,
	current_time: int,
	has_exorcism: bool
) -> int:
	if skill_id <= 0:
		return Result.ERR_NOT_LEARNABLE

	if master_type < MASTER_M or skill_level < 20:
		return Result.ERR_NOT_MASTER_TIER

	if master_type > MASTER_M or skill_level >= 30:
		return Result.ERR_ALREADY_G_OR_P

	if player_exp < SKILL_BOOK_EXP_COST:
		return Result.ERR_INSUFFICIENT_EXP

	if current_time < next_read_time and not has_exorcism:
		return Result.ERR_COOLDOWN

	return 0 # OK

# 研读技能书核心判定逻辑（1:1 char_skill.cpp:488-570）
static func read_skill_book(
	skill_id: int,
	skill_level: int,
	master_type: int,
	read_count: int,
	player_exp: int,
	next_read_time: int,
	current_time: int,
	has_exorcism: bool,
	has_hermit: bool,
	roll_val := -1 # 测试可注入 1..100
) -> Dictionary:
	var err := check_can_read(skill_id, skill_level, master_type, player_exp, next_read_time, current_time, has_exorcism)
	if err != 0:
		return {
			"result": err,
			"skill_id": skill_id,
			"level": skill_level,
			"master_type": master_type,
			"read_count": read_count,
			"exp_consumed": 0,
			"next_read_time": next_read_time,
			"consumed_exorcism": false,
			"consumed_hermit": false,
		}

	var consumed_exorcism := false
	if current_time < next_read_time and has_exorcism:
		consumed_exorcism = true

	var consumed_hermit := false
	var fail_percent := 65 # 40250 char_skill.cpp:525 int percent = 65;
	if has_hermit:
		fail_percent = 0   # 100% 成功
		consumed_hermit = true

	var dice := roll_val if roll_val > 0 else (randi() % 100 + 1)
	var success := (dice > fail_percent)

	var new_level := skill_level
	var new_master := master_type
	var new_read_count := read_count
	var new_next_time := current_time + SKILL_BOOK_DELAY
	var res := Result.FAIL_READ

	if success:
		var need_books := get_need_books(skill_level)
		if read_count + 1 >= need_books:
			# 升级！
			new_level += 1
			new_read_count = 0
			if new_level >= 30:
				new_master = MASTER_G # 突破到 G1
			res = Result.SUCCESS_LEVEL_UP
		else:
			new_read_count += 1
			res = Result.SUCCESS_READ_ONCE

	return {
		"result": res,
		"skill_id": skill_id,
		"level": new_level,
		"master_type": new_master,
		"read_count": new_read_count,
		"exp_consumed": SKILL_BOOK_EXP_COST,
		"next_read_time": new_next_time,
		"consumed_exorcism": consumed_exorcism,
		"consumed_hermit": consumed_hermit,
		"need_books": get_need_books(new_level),
	}

# 魂石修炼逻辑（1:1 G1..G10 -> P）
static func soul_stone_train(
	skill_id: int,
	skill_level: int,
	master_type: int,
	current_karma: int,
	roll_val := -1
) -> Dictionary:
	if master_type != MASTER_G or skill_level < 30 or skill_level >= 40:
		return {"success": false, "err": "not_g_tier"}

	var g_step := skill_level - 30 # 1..10
	var base_cost: int = SOUL_STONE_KARMA_COST.get(g_step, 1000)
	var actual_cost: int = base_cost if current_karma >= 0 else (base_cost * 2)

	var dice := roll_val if roll_val > 0 else (randi() % 100 + 1)
	# 40250 魂石成功率约 30%
	var success := (dice <= 30)

	var new_level := skill_level
	var new_master := master_type
	if success:
		new_level += 1
		if new_level >= 40:
			new_master = MASTER_P

	return {
		"success": success,
		"skill_id": skill_id,
		"level": new_level,
		"master_type": new_master,
		"karma_consumed": actual_cost,
	}

# 格式化官方提示文本
static func get_result_message(res_dict: Dictionary) -> String:
	match res_dict.get("result", -1):
		Result.SUCCESS_LEVEL_UP:
			if res_dict.get("master_type") == MASTER_G and res_dict.get("level") == 30:
				return "领悟了大宗师的奥秘！技能已成功突破至大宗师（G1）！"
			return "完全理解了书中内容，技能成功提升到了新的境界！"
		Result.SUCCESS_READ_ONCE:
			var remaining := int(res_dict.get("need_books", 1)) - int(res_dict.get("read_count", 0))
			return "成功领悟了部分技巧！还需要成功研读 %d 本书以完成突破。" % remaining
		Result.FAIL_READ:
			return "研读失败，未能领悟书中的奥秘。"
		Result.ERR_NOT_LEARNABLE:
			return "无法修炼该技能书。"
		Result.ERR_NOT_MASTER_TIER:
			return "这个技能还未达到大师级别（M），不能通过技能书修炼。"
		Result.ERR_ALREADY_G_OR_P:
			return "这个技能已达到大宗师或以上级别，无法再通过普通技能书提升。"
		Result.ERR_INSUFFICIENT_EXP:
			return "经验值不足（需要 20,000 EXP）。"
		Result.ERR_COOLDOWN:
			var remaining_s := maxi(0, int(res_dict.get("next_read_time", 0)))
			return "当前处于研读冷却中，请使用驱魔卷轴消除冷却或稍后再试。"
		_:
			return ""