# MouseController —— ClientVS22 mousemodule.py 的全局物品拖放层。
#
# 目标控件通过 register_target() 注册；物品源调用 attach_item() 后，控制器
# 接管鼠标释放，命中目标时调用回调，释放到窗口外 / 右键 / ESC / 失焦则取消。
# 光标状态由 CursorManager 管理，跟随图标不参与世界点击。
extends Node

const CursorManager = preload("res://ui/cursor_manager.gd")

var cursor: Node
var audio: Node
var _overlay: Control
var _icon: TextureRect
var _label: Label
var _attached: Dictionary = {}
var _targets: Array[Dictionary] = []
var _touch_index := -1
var _touch_position := Vector2.ZERO
var world_drop_handler: Callable

func setup(parent: Node, cursor_manager: Node = null, audio_node: Node = null) -> void:
	cursor = cursor_manager
	audio = audio_node
	_overlay = Control.new()
	_overlay.name = "MouseItemOverlay"
	_overlay.mouse_filter = Control.MOUSE_FILTER_IGNORE
	_overlay.z_index = 1000
	_overlay.visible = false
	_overlay.size = Vector2(72, 72)
	parent.add_child(_overlay)
	_icon = TextureRect.new()
	_icon.position = Vector2(0, 0)
	_icon.size = Vector2(48, 48)
	_icon.expand_mode = TextureRect.EXPAND_IGNORE_SIZE
	_icon.stretch_mode = TextureRect.STRETCH_KEEP_ASPECT_CENTERED
	_icon.mouse_filter = Control.MOUSE_FILTER_IGNORE
	_overlay.add_child(_icon)
	_label = Label.new()
	_label.position = Vector2(2, 48)
	_label.size = Vector2(68, 20)
	_label.add_theme_font_size_override("font_size", 10)
	_label.mouse_filter = Control.MOUSE_FILTER_IGNORE
	_overlay.add_child(_label)
	set_process_input(true)

var _drag_started := false
var _attach_pos := Vector2(-1, -1)
var _just_attached := false

func _on_attach() -> void:
	_drag_started = false
	_just_attached = true
	if is_inside_tree():
		_attach_pos = get_viewport().get_mouse_position()
	else:
		_attach_pos = Vector2(-1, -1)

func attach_item(window: int, cell: int, vnum: int, count: int,
		texture: Texture2D = null, source := "inventory", metadata: Dictionary = {},
		touch_index := -1, touch_position := Vector2(-1, -1)) -> bool:
	if vnum <= 0 or window < 0 or cell < 0:
		return false
	_attached = {"window": window, "cell": cell, "vnum": vnum,
			"count": maxi(1, count), "source": source}
	_touch_index = touch_index
	if touch_position.x >= 0.0 and touch_position.y >= 0.0:
		_touch_position = touch_position
	# Keep the instance fields that the reference mouse module exposes to the
	# receiving window (anti flags, sockets, attributes, ...), while retaining
	# the canonical source coordinates supplied by the caller.
	for key in metadata:
		if key not in ["window", "cell", "vnum", "count", "source"]:
			_attached[key] = metadata[key]
	if _icon:
		_icon.texture = texture
		_icon.visible = texture != null
	if _label:
		_label.text = "#%d%s" % [vnum, (" ×%d" % count) if count > 1 else ""]
		_label.visible = true
	if _overlay:
		_overlay.visible = true
	if cursor and cursor.has_method("set_cursor"):
		cursor.set_cursor(CursorManager.ITEM)
	_play_ui("pick.wav")
	_on_attach()
	return true

func attach_money(amount: int, source := "inventory") -> bool:
	if amount <= 0:
		return false
	_attached = {"window": -1, "cell": -1, "vnum": -1, "count": amount,
			"source": source, "money": true}
	_touch_index = -1
	_touch_position = Vector2.ZERO
	if _icon:
		_icon.texture = null
		_icon.visible = false
	if _label:
		_label.text = "金币 ×%d" % amount
		_label.visible = true
	if _overlay:
		_overlay.visible = true
	if cursor and cursor.has_method("set_cursor"):
		cursor.set_cursor(CursorManager.ITEM)
	_play_ui("pick.wav")
	_on_attach()
	return true

func attach_skill(skill_id: int, slot_idx: int = 0, texture: Texture2D = null,
		skill_name := "", touch_index := -1, touch_position := Vector2(-1, -1)) -> bool:
	if skill_id <= 0:
		return false
	_attached = {
		"source": "skill",
		"skill_id": skill_id,
		"slot_idx": slot_idx,
	}
	_touch_index = touch_index
	if touch_position.x >= 0.0 and touch_position.y >= 0.0:
		_touch_position = touch_position
	if _icon:
		_icon.texture = texture
		_icon.visible = texture != null
	if _label:
		_label.text = skill_name if skill_name != "" else "技能 %d" % skill_id
		_label.visible = true
	if _overlay:
		_overlay.visible = true
	if cursor and cursor.has_method("set_cursor"):
		cursor.set_cursor(CursorManager.ITEM)
	_play_ui("pick.wav")
	_on_attach()
	return true

func attach_emotion(emote_id: int, texture: Texture2D = null,
		emote_name := "", touch_index := -1, touch_position := Vector2(-1, -1)) -> bool:
	if emote_id <= 0:
		return false
	_attached = {
		"source": "emotion",
		"emote_id": emote_id,
	}
	_touch_index = touch_index
	if touch_position.x >= 0.0 and touch_position.y >= 0.0:
		_touch_position = touch_position
	if _icon:
		_icon.texture = texture
		_icon.visible = texture != null
	if _label:
		_label.text = emote_name if emote_name != "" else "动作 %d" % emote_id
		_label.visible = true
	if _overlay:
		_overlay.visible = true
	if cursor and cursor.has_method("set_cursor"):
		cursor.set_cursor(CursorManager.ITEM)
	_play_ui("pick.wav")
	_on_attach()
	return true

func cancel() -> void:
	_attached.clear()
	_touch_index = -1
	_touch_position = Vector2.ZERO
	_drag_started = false
	_attach_pos = Vector2(-1, -1)
	_just_attached = false
	if _overlay:
		_overlay.visible = false
	if cursor and cursor.has_method("reset"):
		cursor.reset()

func is_attached() -> bool:
	return not _attached.is_empty()

func attached() -> Dictionary:
	return _attached.duplicate(true)

func register_target(control: Control, callback: Callable, owner: Node = null) -> void:
	if control == null or not callback.is_valid():
		return
	_targets.append({"control": control, "callback": callback, "owner": owner})

func unregister_owner(owner: Node) -> void:
	for i in range(_targets.size() - 1, -1, -1):
		if _targets[i].get("owner", null) == owner:
			_targets.remove_at(i)

func _process(_dt: float) -> void:
	if _overlay and _overlay.visible:
		var position := get_viewport().get_mouse_position()
		if _touch_index >= 0:
			position = _touch_position
		_overlay.global_position = position + Vector2(12, 12)
	# 清理已被窗口销毁的目标，防止拖放回调落到旧 UI。
	for i in range(_targets.size() - 1, -1, -1):
		var c: Control = _targets[i].get("control", null)
		if c == null or not is_instance_valid(c):
			_targets.remove_at(i)

func _set_handled() -> void:
	var vp := get_viewport()
	if vp:
		vp.set_input_as_handled()

func _input(event: InputEvent) -> void:
	if not is_attached():
		return
	if event is InputEventKey and event.pressed and event.keycode == KEY_ESCAPE:
		cancel()
		_set_handled()
		return
	if event is InputEventMouseButton and event.pressed and event.button_index == MOUSE_BUTTON_RIGHT:
		cancel()
		_set_handled()
		return
	if event is InputEventMouseMotion:
		if _attach_pos.x >= 0.0 and (_attach_pos - event.position).length() > 6.0:
			_drag_started = true
		return
	if event is InputEventMouseButton and event.button_index == MOUSE_BUTTON_LEFT:
		if event.pressed:
			# If user already picked up an item and left-clicks on a target:
			if not _just_attached:
				if _drop_at(event.position):
					_set_handled()
					return
				# If clicked outside any target, cancel attachment
				if _attach_pos.x >= 0.0 and (_attach_pos - event.position).length() > 6.0:
					_play_ui("loginfail.wav")
					cancel()
					_set_handled()
					return
		else:
			# Left mouse release (not pressed)
			_just_attached = false
			# If dragged, attempt drop at release position
			if _drag_started or (_attach_pos.x >= 0.0 and (_attach_pos - event.position).length() > 8.0):
				_drop_at(event.position)
				_set_handled()
				return
			# If not dragged (clicked to pick up), keep item attached to cursor!
			return
	if event is InputEventScreenDrag and event.index == _touch_index:
		_touch_position = event.position
		_set_handled()
		return
	if event is InputEventScreenTouch and not event.pressed and event.index == _touch_index:
		_touch_position = event.position
		_drop_at(event.position)
		_set_handled()

func _drop_at(position: Vector2) -> bool:
	var payload := attached()
	if payload.is_empty():
		return false

	var icon_center := position + Vector2(24, 24)
	var best_idx := -1
	var best_dist := 999999.0

	# Pass 1: exact hit test (cursor position or icon center)
	for i in range(_targets.size() - 1, -1, -1):
		var c: Control = _targets[i].get("control", null)
		if c == null or not is_instance_valid(c):
			_targets.remove_at(i)
			continue
		if not c.visible:
			continue
		var rect := c.get_global_rect()
		if rect.has_point(position):
			var d := position.distance_to(rect.get_center())
			if d < best_dist:
				best_dist = d
				best_idx = i
		elif rect.has_point(icon_center):
			var d := icon_center.distance_to(rect.get_center())
			if d < best_dist:
				best_dist = d
				best_idx = i

	# Pass 2: generous hit test with 16px tolerance margin
	if best_idx < 0:
		for i in range(_targets.size() - 1, -1, -1):
			var c: Control = _targets[i].get("control", null)
			if c == null or not is_instance_valid(c) or not c.visible:
				continue
			var rect := c.get_global_rect().grow(16.0)
			if rect.has_point(position):
				var d := position.distance_to(rect.get_center())
				if d < best_dist:
					best_dist = d
					best_idx = i
			elif rect.has_point(icon_center):
				var d := icon_center.distance_to(rect.get_center())
				if d < best_dist:
					best_dist = d
					best_idx = i

	if best_idx >= 0:
		var cb: Callable = _targets[best_idx].get("callback", Callable())
		if cb.is_valid():
			var ok := false
			if cb.get_argument_count() >= 2:
				ok = bool(cb.call(payload, position))
			else:
				ok = bool(cb.call(payload))
			if ok:
				_play_ui("drop.wav")
				cancel()
				return true

	if world_drop_handler.is_valid():
		var ok := false
		if world_drop_handler.get_argument_count() >= 2:
			ok = bool(world_drop_handler.call(payload, position))
		else:
			ok = bool(world_drop_handler.call(payload))
		if ok:
			_play_ui("drop.wav")
			cancel()
			return true

	_play_ui("loginfail.wav")
	cancel()
	return false

func _play_ui(name: String) -> void:
	if audio and audio.has_method("play_ui"):
		audio.play_ui(name)

func _notification(what: int) -> void:
	if what == NOTIFICATION_WM_WINDOW_FOCUS_OUT:
		cancel()