# net_trace —— 主角 vid 生命周期取证。
#
# 实机进游戏后画面全灰、主角是蓝胶囊：GAMESCENE_DIAG 显示地图正常装载，
# 但 main_vid=0、主角实体为空 —— 主角在 setup() 之后被从 EntityStore 里
# 摘掉了。C++ 侧能把 m_main_vid 清零的路只有三条（mut_despawn /
# m2dev GC_CHARACTER_DEL / reset_for_map_change），前两条会发
# entity_despawned 信号，第三条会清空 m_changes、悄悄归零。
# 这个节点每帧轮询 main_vid 并记录信号，于是「哪条路」直接可读：
#   MAIN_LOST reason=despawn  → GC_CHARACTER_DEL 命中了主角
#   MAIN_LOST reason=silent   → reset_for_map_change（warp）或别的静默清零
#
# 常驻但极廉价（一次 get_main_vid + 一个整数比较）；只在事件发生时打印。
extends Node

const RING := 24

var _client: Node = null
var _main_vid := 0
var _t0 := 0
var _ring: Array[String] = []
var _verbose := false

func setup(client: Node) -> void:
	_client = client
	_t0 = Time.get_ticks_msec()
	# 主角在进场那几秒会被服务器 DEL+ADD 若干次（参考端同样如此），逐条打太吵，
	# 默认只报异常；MT_NETTRACE=1 才打全量。
	_verbose = OS.get_environment("MT_NETTRACE") == "1"
	for sig in ["entity_main_set", "entity_despawned", "entity_spawned",
			"entered_game", "disconnected", "stage_changed", "phase_changed",
			"world_reset", "warp"]:
		if client.has_signal(sig):
			client.connect(sig, Callable(self, "_on_" + sig))

func _ms() -> int:
	return Time.get_ticks_msec() - _t0

func _note(line: String) -> void:
	var s := "+%dms %s" % [_ms(), line]
	_ring.append(s)
	if _ring.size() > RING:
		_ring.pop_front()

func _dump(head: String) -> void:
	printerr("NETTRACE: ", head)
	for s in _ring:
		printerr("NETTRACE:   ", s)

func _on_entity_main_set(vid: int) -> void:
	_note("main_set vid=%d" % vid)
	if _verbose:
		printerr("NETTRACE: MAIN_SET vid=%d t=+%dms" % [vid, _ms()])

func _on_entity_spawned(entity: Dictionary) -> void:
	var vid := int(entity.get("vid", 0))
	if vid == _main_vid or bool(entity.get("is_main", false)):
		_note("spawn vid=%d race=%s is_main=%s" % [vid,
				str(entity.get("race", null)), str(entity.get("is_main", false))])

func _on_entity_despawned(vid: int) -> void:
	_note("despawn vid=%d" % vid)
	if vid == _main_vid:
		_note("*** despawn hit MAIN vid=%d" % vid)

func _on_entered_game() -> void:
	_note("entered_game")

func _on_disconnected(reason: String) -> void:
	_note("disconnected " + reason)
	printerr("NETTRACE: DISCONNECTED %s t=+%dms" % [reason, _ms()])

func _on_world_reset() -> void:
	_note("world_reset (reset_for_map_change)")

func _on_warp(pos: Vector3, _reconnect: bool) -> void:
	_note("warp " + str(pos))

func _on_stage_changed(stage: String) -> void:
	_note("stage=" + stage)

func _on_phase_changed(phase: String) -> void:
	_note("phase=" + phase)

func _process(_dt: float) -> void:
	if _client == null or not _client.has_method("get_main_vid"):
		return
	var vid := int(_client.get_main_vid())
	if vid == _main_vid:
		return
	if vid != 0 and _main_vid == 0:
		_main_vid = vid
		_note("main_vid 0 -> %d" % vid)
		return
	# 丢主角：把最近的事件环一起打出来，能读出是 despawn 还是静默清零。
	var was := _main_vid
	_main_vid = vid
	var reason := "silent"
	for s in _ring:
		if s.ends_with("despawn hit MAIN vid=%d" % was):
			reason = "despawn"
	_dump("MAIN_LOST was=%d now=%d reason=%s t=+%dms" % [was, vid, reason, _ms()])