# VERTICAL SLICE - NOT FOR PRODUCTION
# Validation Question: 玩家能否无指导在一场完整战斗中经历「开战→挖掘规划→轮末结算逐行兑现→胜/负」并逐行归因（P2）
# Date: 2026-09-10
# 增益状态·统一状态容器：三向效果同构实例 · 单一时限量纲 remaining_settlements（先兑付后衰减）·
# 按行叠层（stack 授予不触碰 R）· 授予时数值快照抗热重载 · 零随机零信号。
# 注：MVP 单敌假设经 敌人系统 回验不成立（定多敌）——enemy 侧 side-wide 语义按 registry 改写执行。
# 实现 GDD：design/archive/gdd-2026-09-14/b3-status-effect.md（系统 ID B3·增益状态——registry 追溯锚，命名规范见 CLAUDE.md）
class_name StatusContainer
extends RefCounted

var db: ConfigDb
var _open := false
var _instances: Array[Dictionary] = []   # 插入序；元素 = {effect_id, layers, remaining, source_class, origin_cell, round_index, snap_m, snap_unit, snap_display}


func _init(db_ref: ConfigDb) -> void:
	db = db_ref


func notify_battle_start() -> bool:
	if _open:
		push_warning("[增益状态] Active 下重复 notify_battle_start（EC11）")
		return false
	_open = true
	_instances.clear()
	return true


# 唯一授予入口（挖掘期零直写——战斗结算 结算编排期统一调用）。
# duration_override（敌人技能池批——增益技施放）：技能行 buff_duration 覆盖状态行时长（-1 = 状态表值）。
# 施放是持续量的 owner（proposal §2.2 字段词汇表"buff_duration 增益持续回合数"）；其他授予路径传缺省。
func apply_effect(effect_id: String, source: Dictionary, duration_override: int = -1) -> bool:
	if not _open:
		push_warning("[增益状态] 域闭授予（EC1）")
		return false
	var row: Dictionary = db.status_effect_row(effect_id)
	if row.is_empty():
		push_warning("[增益状态] 未知 effect_id（EC2）: %s" % effect_id)
		return false
	var policy: String = row.stack_policy
	var dur: int = int(row.duration_settlements) if duration_override < 1 else duration_override
	var max_stack: int = int(row.max_stack)
	# 授予时快照（抗表重载——EC9）
	var snap_m: int = int(row.magnitude)
	var snap_unit: String = String(row.unit)
	var snap_display: String = String(row.display_name)
	match policy:
		"independent":
			_instances.append(_new_instance(effect_id, 1, dur, source, snap_m, snap_unit, snap_display))
			return true
		"refresh":
			for inst in _instances:
				if inst.effect_id == effect_id:
					inst.remaining = dur   # R ← D（取实例快照 D——同表值）；L 不变；空刷新恒 true
					return true
			_instances.append(_new_instance(effect_id, 1, dur, source, snap_m, snap_unit, snap_display))
			return true
		"stack":
			for inst in _instances:
				if inst.effect_id == effect_id:
					if inst.layers >= max_stack:
						return false   # 满层拒绝原子——容器零写入（拒收由战斗结算记"奖励未生效"行）
					inst.layers += 1   # stack 授予不触碰 R（spec 决议）
					return true
			_instances.append(_new_instance(effect_id, 1, dur, source, snap_m, snap_unit, snap_display))
			return true
	push_warning("[增益状态] 未知 stack_policy")
	return false


func _new_instance(effect_id: String, layers: int, dur: int, source: Dictionary, m: int, unit: String, display: String) -> Dictionary:
	return {
		"effect_id": effect_id,
		"layers": layers,
		"remaining": dur,
		"source_class": String(source.get("source_class", "")),
		"origin_cell": source.get("origin_cell", Vector2i(-1, -1)),
		"round_index": int(source.get("round_index", 0)),
		"snap_m": m,
		"snap_unit": unit,
		"snap_display": display,
	}


# 只读投影（插入序稳定枚举；六归因字段 + display_name + 授予时快照）
func query_active(side: String) -> Array:
	var out: Array[Dictionary] = []
	for inst in _instances:
		var row: Dictionary = db.status_effect_row(inst.effect_id)
		if row.is_empty():
			continue
		if String(row.target_side) != side:
			continue
		out.append({
			"effect_id": inst.effect_id,
			"layers": inst.layers,
			"remaining_settlements": inst.remaining,
			"source_class": inst.source_class,
			"origin_cell": inst.origin_cell,
			"round_index": inst.round_index,
			"display_name": inst.snap_display,
			"snap_magnitude": inst.snap_m,
			"snap_unit": inst.snap_unit,
			"effective_value": inst.layers * inst.snap_m,   # L×m 加算（percent 越域不 clamp——收口归 战斗结算）
		})
	return out


# 池层数读值（战斗结算·战斗段伏击池 L 的消费面）
func pool_layers(effect_id: String) -> int:
	for inst in _instances:
		if inst.effect_id == effect_id:
			return inst.layers
	return 0


# 轮末衰减：先兑付后衰减；每实例恰 −1；归 0 移除；返回移除数 k（恰一次执行由 战斗结算 编排信任承载）
func decay_round() -> int:
	if not _open:
		return 0   # EC13 域闭兜底读法——容器恒空，无独立分支不诊断
	var k := 0
	var survivors: Array[Dictionary] = []
	for inst in _instances:
		inst.remaining -= 1
		if inst.remaining <= 0:
			k += 1
		else:
			survivors.append(inst)
	_instances = survivors
	return k


func notify_battle_end() -> bool:
	if not _open:
		push_warning("[增益状态] BattleClosed 下重复 notify_battle_end（EC11）")
		return false
	_open = false
	_instances.clear()   # 全清不跨战斗
	return true