# DungeonState —— GC_DUNGEON 目的地状态（40250/ClientVS22）。
#
# 参考端 PythonNetworkStreamPhaseGame.cpp:3875-3901 收到目的地后调用
# CPythonPlayer::SetDungeonDestinationPosition；PythonPlayer.cpp:147-167、
# :1255-1285 保存全局像素/厘米坐标、立即提示，并在接近目标后清除，未到达时
# 每 20 秒再次提示。本工程把目标状态与 UI 解耦，UI 只消费信号。
extends Node

signal destination_changed(active: bool, world_pos: Vector3)
signal destination_reached(world_pos: Vector3)
signal alarm_requested(world_pos: Vector3)

const TIME_ATTACK_START := 0
const DESTINATION_POSITION := 1
const ARRIVAL_THRESHOLD_CM := 10000.0
const ALARM_INTERVAL_SEC := 20.0

var client: Node
var player_getter: Callable
var active := false
var destination_cm := Vector2.ZERO
var destination_world := Vector3.ZERO
var last_subheader := -1
var alarm_count := 0
var _last_alarm_ms := -1

func setup(m2client: Node, get_player: Callable) -> void:
	client = m2client
	player_getter = get_player
	if client and client.has_signal("dungeon_event"):
		client.dungeon_event.connect(_on_dungeon_event)
	if client and client.has_signal("world_reset"):
		client.world_reset.connect(clear)

func _on_dungeon_event(subheader: int, x: int, y: int, has_destination: bool) -> void:
	last_subheader = subheader
	# ClientVS22's TIME_ATTACK_START branch is intentionally empty. Consume the
	# packet but do not invent a local timer that the reference client does not run.
	if subheader != DESTINATION_POSITION or not has_destination:
		return
	destination_cm = Vector2(float(x), float(y))
	# GC_DUNGEON carries TPixelPosition x/y in global server centimetres. The
	# network frame uses -Y for Godot Z before MapCoord applies the map base.
	destination_world = MapCoord.to_world(Vector3(float(x) * 0.01, 0.0, -float(y) * 0.01))
	active = true
	_last_alarm_ms = -1
	destination_changed.emit(true, destination_world)
	_alarm()

func clear() -> void:
	var was_active := active
	active = false
	destination_cm = Vector2.ZERO
	destination_world = Vector3.ZERO
	_last_alarm_ms = -1
	if was_active:
		destination_changed.emit(false, Vector3.ZERO)

func _player() -> Node3D:
	if not player_getter.is_valid():
		return null
	var p: Variant = player_getter.call()
	return p as Node3D

func _alarm() -> void:
	_last_alarm_ms = Time.get_ticks_msec()
	alarm_count += 1
	alarm_requested.emit(destination_world)

func _process(_dt: float) -> void:
	if not active:
		return
	var p := _player()
	if p:
		# Match PythonPlayer.cpp:155: integer Manhattan distance, not Euclidean.
		var p_cm := MapCoord.to_server_cm(p.global_position)
		var distance_cm := absf(p_cm.x - destination_cm.x) + absf(p_cm.y - destination_cm.y)
		if distance_cm < ARRIVAL_THRESHOLD_CM:
			var reached := destination_world
			active = false
			destination_changed.emit(false, reached)
			destination_reached.emit(reached)
			return
	var now := Time.get_ticks_msec()
	if _last_alarm_ms < 0 or now - _last_alarm_ms > int(ALARM_INTERVAL_SEC * 1000.0):
		_alarm()