# UiManager (P1) —— 窗口栈：打开 / 关闭 / 置顶 / ESC 关顶层 / modal 变暗 / 标题栏拖动。
#
#   var ui := preload("res://ui/ui_manager.gd").new()
#   add_child(ui)
#   ui.locale = func(k): return Locale.t(k)
#   var w := ui.open_script("res://../assets/uiscript/uiscript/systemdialog.py", assets_root)
#   w.nodes["close_button"].pressed.connect(func(): ui.close(w.root))
#
# open_script 返回 { root: Control, nodes: {name: Control} }（同 UiBuild.build）。
extends CanvasLayer

const UiScript = preload("res://ui/uiscript.gd")
const UiBuild = preload("res://ui/ui_build.gd")
const MobileWindowHost = preload("res://ui/mobile/mobile_window_host.gd")

signal window_opened(root: Control)
signal window_closed(root: Control)

var locale: Callable
var screen := Vector2i(1920, 1080)
var mobile_mode := false
var mobile_screen := Vector2i(844, 390)

var _root: Control          # 全屏容器
var _dim: ColorRect         # modal 变暗层
var _mobile_blocker: ColorRect
var _stack: Array[Control] = []
var _mobile_external: Array[Dictionary] = []
var _mobile_modals: Array[Node] = []
var _mobile_saved: Dictionary = {}
var _mobile_close_callbacks: Dictionary = {}
var _last_mobile_area := Rect2(-1, -1, 0, 0)
var _drag_win: Control = null
var _drag_from := Vector2.ZERO

func _ready() -> void:
	layer = 10
	_root = Control.new()
	_root.set_anchors_preset(Control.PRESET_FULL_RECT)
	_root.mouse_filter = Control.MOUSE_FILTER_IGNORE
	add_child(_root)
	_dim = ColorRect.new()
	_dim.color = Color(0, 0, 0, 0.45)
	_dim.set_anchors_preset(Control.PRESET_FULL_RECT)
	_dim.visible = false
	_root.add_child(_dim)
	_mobile_blocker = ColorRect.new()
	_mobile_blocker.name = "MobileWindowBlocker"
	_mobile_blocker.color = Color(0, 0, 0, 0)
	_mobile_blocker.set_anchors_preset(Control.PRESET_FULL_RECT)
	_mobile_blocker.mouse_filter = Control.MOUSE_FILTER_STOP
	_mobile_blocker.visible = false
	_root.add_child(_mobile_blocker)
	set_process_input(true)
	set_process_unhandled_input(true)
	set_process(true)

## Select the presentation policy without changing any feature controller.
## Mobile windows are rebuilt with the landscape design resolution and hosted
## inside the safe area; desktop keeps the historical 1920x1080 parser space.
func set_mobile_mode(enabled: bool) -> void:
	mobile_mode = enabled
	if enabled:
		screen = mobile_screen
		layer = 30
		_last_mobile_area = Rect2(-1, -1, 0, 0)
	else:
		screen = Vector2i(1920, 1080)
		layer = 10
		_last_mobile_area = Rect2(-1, -1, 0, 0)
	if not enabled:
		for record in _mobile_external.duplicate():
			var root: Control = record.get("root")
			if root and is_instance_valid(root):
				_dismiss_external(root)
	_restack()

func track_mobile_window(root: Control, title := "", close_cb := Callable()) -> void:
	if root == null:
		return
	for record in _mobile_external:
		if record.get("root") == root:
			record["title"] = title
			record["close_cb"] = close_cb
			return
	_mobile_external.append({"root": root, "title": title, "close_cb": close_cb})
	if mobile_mode and root.visible:
		_sync_mobile_windows()

## Register a native Window/ConfirmationDialog that is created outside a
## feature's hosted Control. It remains owned by the feature, but the mobile
## manager can block world input and make Android back press its cancel action
## first. This avoids moving native dialogs into a Control tree.
func track_mobile_modal(popup: Node) -> void:
	if popup == null:
		return
	if not _mobile_modals.has(popup):
		_mobile_modals.append(popup)
	popup.set_meta("mobile_modal", true)
	MobileWindowHost.wire_buttons(popup)

func reflow_mobile_window(root: Control) -> void:
	if not mobile_mode or root == null or not is_instance_valid(root):
		return
	if not _stack.has(root):
		return
	MobileWindowHost.install(root, _mobile_area(), _window_title(root),
			Callable(self, "_close_hosted_window").bind(root))
	_restack()

# --- open / close --------------------------------------------------------

func build_script(path: String, assets_root: String) -> Dictionary:
	var us := UiScript.new()
	us.screen = screen
	if locale.is_valid():
		us.locale = locale
	var spec := us.parse_file(path)
	if spec.is_empty():
		push_warning("UiManager: parse failed (%s): %s" % [path, us.last_error])
		return {"root": Control.new(), "nodes": {}}
	return UiBuild.build(spec, assets_root)

# 解析 + 构建 + 打开，返回 { root, nodes }
func open_script(path: String, assets_root: String, modal := false) -> Dictionary:
	var r := build_script(path, assets_root)
	open(r.root, modal)
	return r

func open(win: Control, modal := false) -> void:
	if win.get_parent() == null:
		_root.add_child(win)
	win.set_meta("modal", modal)
	if mobile_mode:
		MobileWindowHost.install(win, _mobile_area(), _window_title(win),
			Callable(self, "_close_hosted_window").bind(win))
	else:
		_wire_drag(win)
	_stack.erase(win)
	_stack.append(win)
	_restack()
	window_opened.emit(win)

func close(win: Control) -> void:
	if win == null:
		return
	if bool(win.get_meta("mobile_external", false)):
		var cb: Callable = _mobile_close_callbacks.get(win, Callable())
		if cb.is_valid() and win.visible:
			cb.call()
		else:
			_dismiss_external(win)
		return
	_stack.erase(win)
	if win.get_parent():
		win.get_parent().remove_child(win)
	win.queue_free()
	_restack()
	window_closed.emit(win)

func close_top() -> bool:
	if _close_mobile_popup():
		return true
	if _stack.is_empty():
		return false
	var win := _stack[-1]
	if bool(win.get_meta("mobile_external", false)):
		var cb: Callable = _mobile_close_callbacks.get(win, Callable())
		if cb.is_valid():
			cb.call()
		else:
			_dismiss_external(win)
	else:
		close(win)
	return true

func top() -> Control:
	return _stack[-1] if not _stack.is_empty() else null

# wndMgr 的输入边界：鼠标不能从打开的窗口下方穿透到世界；模态确认框（LockWindow）
# 只允许 ESC 回到窗口栈。键盘按 CWindowManager::RunKeyDown：非模态窗口不截键。
func blocks_game_input(event: InputEvent) -> bool:
	var popup := _mobile_modal_popup()
	if popup != null:
		return not (event is InputEventKey and event.keycode == KEY_ESCAPE)
	if _stack.is_empty():
		return false
	var top_window: Control = _stack[-1]
	if top_window == null or not is_instance_valid(top_window) or not top_window.visible:
		return false
	if bool(top_window.get_meta("modal", false)):
		return not (event is InputEventKey and event.keycode == KEY_ESCAPE)
	if mobile_mode and event is InputEventScreenTouch:
		return true
	if mobile_mode and event is InputEventScreenDrag:
		return true
	if event is InputEventMouse:
		return top_window.get_global_rect().has_point(event.position)
	# 键盘：没有 LockWindow 时键先给 ActiveWindow（输入框——Godot 里由获得焦点的控件在
	# gui_input 中自行吃掉），其余落到 game.py OnKeyDown，所以技能窗 / 背包开着时
	# 快捷栏 1-4 / F1-F4、Space 普攻和开关窗键都照常生效。
	return false

func _input(event: InputEvent) -> void:
	# Keyboard events do not automatically enter Control.gui_input. Consume
	# blocked keys here, before PlayerController/GameCamera receive them through
	# _unhandled_input; mouse events remain available to child controls.
	if event is InputEventKey and blocks_game_input(event):
		get_viewport().set_input_as_handled()

func _process(_delta: float) -> void:
	if mobile_mode:
		var area := _mobile_area()
		if not area.is_equal_approx(_last_mobile_area):
			_last_mobile_area = area
			_reflow_mobile_windows(area)
		_sync_mobile_windows()
		# Password/confirmation dialogs are created by feature controllers after
		# their window is hosted.  Wire their buttons too, including dialogs that
		# appear as siblings under UiManager's root.
		MobileWindowHost.wire_buttons(_root)
		for win in _stack:
			if win and is_instance_valid(win):
				MobileWindowHost.wire_buttons(win)
		for popup in _mobile_modals.duplicate():
			if popup == null or not is_instance_valid(popup):
				_mobile_modals.erase(popup)
			else:
				MobileWindowHost.wire_buttons(popup)

func _reflow_mobile_windows(area: Rect2) -> void:
	# Safe areas can change while the logical viewport stays the same (for
	# example when a keyboard, call bar or system gesture inset appears). Keep
	# every already-open feature inside the new area instead of waiting for a
	# full window resize.
	for win in _stack.duplicate():
		if win == null or not is_instance_valid(win) or not win.visible:
			continue
		MobileWindowHost.install(win, area, _window_title(win),
				Callable(self, "_close_hosted_window").bind(win))

func _sync_mobile_windows() -> void:
	for record in _mobile_external:
		var root: Control = record.get("root")
		if root == null or not is_instance_valid(root):
			continue
		if root.visible and not _stack.has(root):
			_present_external(root, String(record.get("title", "")),
				record.get("close_cb", Callable()))
		elif not root.visible and _stack.has(root):
			_dismiss_external(root)

func _mobile_area() -> Rect2:
	return MobileWindowHost.safe_rect(get_viewport())

func _window_title(win: Control) -> String:
	if win == null:
		return ""
	var title := String(win.get_meta("mobile_title", ""))
	if title != "":
		return title
	return String(win.name) if win.name != "Control" else "功能"

func _close_hosted_window(win: Control) -> void:
	close(win)

func _present_external(root: Control, title: String, close_cb: Callable) -> void:
	if root == null or not is_instance_valid(root) or _stack.has(root):
		return
	var parent := root.get_parent()
	if parent == null:
		return
	var saved := {
		"parent": parent,
		"position": root.position,
		"size": root.size,
		"scale": root.scale,
		"pivot": root.pivot_offset,
		"anchor_left": root.anchor_left,
		"anchor_top": root.anchor_top,
		"anchor_right": root.anchor_right,
		"anchor_bottom": root.anchor_bottom,
	}
	_mobile_saved[root] = saved
	parent.remove_child(root)
	_root.add_child(root)
	root.set_meta("mobile_external", true)
	root.set_meta("modal", false)
	_mobile_close_callbacks[root] = close_cb
	MobileWindowHost.install(root, _mobile_area(), title, close_cb)
	_stack.append(root)
	_restack()

func _dismiss_external(root: Control) -> void:
	if root == null:
		return
	_stack.erase(root)
	_mobile_close_callbacks.erase(root)
	MobileWindowHost.uninstall(root)
	var saved: Dictionary = _mobile_saved.get(root, {})
	if root.get_parent() == _root:
		_root.remove_child(root)
	var parent: Node = saved.get("parent")
	if parent and is_instance_valid(parent):
		parent.add_child(root)
	if not saved.is_empty():
		root.position = saved.get("position", root.position)
		root.size = saved.get("size", root.size)
		root.scale = saved.get("scale", Vector2.ONE)
		root.pivot_offset = saved.get("pivot", Vector2.ZERO)
		root.anchor_left = float(saved.get("anchor_left", root.anchor_left))
		root.anchor_top = float(saved.get("anchor_top", root.anchor_top))
		root.anchor_right = float(saved.get("anchor_right", root.anchor_right))
		root.anchor_bottom = float(saved.get("anchor_bottom", root.anchor_bottom))
	_mobile_saved.erase(root)
	root.set_meta("mobile_external", false)
	_restack()
	window_closed.emit(root)

func _restack() -> void:
	var any_modal := false
	for i in _stack.size():
		var w := _stack[i]
		w.move_to_front()
		if bool(w.get_meta("modal", false)):
			any_modal = true
	_dim.visible = any_modal
	_mobile_blocker.visible = mobile_mode and not _stack.is_empty()
	if _mobile_blocker:
		_root.move_child(_mobile_blocker, 0)
	if any_modal:
		# 变暗层紧贴在最顶层 modal 之下
		_dim.move_to_front()
		_stack[-1].move_to_front()

# --- ESC ---------------------------------------------------------------

func _unhandled_input(e: InputEvent) -> void:
	if e is InputEventKey and e.pressed and e.keycode == KEY_ESCAPE:
		if _close_mobile_popup():
			get_viewport().set_input_as_handled()
			return
		if close_top():
			get_viewport().set_input_as_handled()

func _mobile_modal_popup() -> Node:
	if not mobile_mode or _root == null:
		return null
	for popup in _mobile_modals:
		if popup and is_instance_valid(popup) and _node_visible(popup):
			return popup
	for node in _root.find_children("*", "", true, false):
		if (node is Window or bool(node.get_meta("mobile_modal", false))) and _node_visible(node):
			return node
	return null

func _node_visible(node: Node) -> bool:
	if node is CanvasItem:
		return (node as CanvasItem).visible
	if node is Window:
		return (node as Window).visible
	return false

func _close_mobile_popup() -> bool:
	var popup := _mobile_modal_popup()
	if popup == null:
		return false
	var close_cb: Variant = popup.get_meta("mobile_modal_close", Callable())
	if close_cb is Callable and close_cb.is_valid():
		close_cb.call()
		return true
	# ConfirmationDialog owners generally use the canceled signal to clear
	# pending state.  Drive its cancel button when available; plain dialogs can
	# safely be hidden on back.
	if popup is ConfirmationDialog and popup.has_method("get_cancel_button"):
		var cancel = popup.call("get_cancel_button")
		if cancel is BaseButton and not cancel.disabled:
			cancel.pressed.emit()
			return true
	popup.hide()
	return true

# --- 标题栏拖动 --------------------------------------------------------

func _wire_drag(win: Control) -> void:
	var handle := _find_drag_handle(win)
	if handle == null or handle.has_meta("_drag_wired"):
		return
	handle.set_meta("_drag_wired", true)
	handle.mouse_filter = Control.MOUSE_FILTER_STOP
	handle.gui_input.connect(func(ev: InputEvent): _on_handle_input(win, ev))

func _find_drag_handle(win: Control) -> Control:
	# 优先 titlebar；否则 board_with_titlebar 的顶部条；否则整个 window 根
	for n in win.find_children("*", "", true, false):
		if n is Control and (n.get_meta("is_titlebar", false) or n.get_meta("titlebar_h", 0) > 0):
			return n
	return win

func _on_handle_input(win: Control, ev: InputEvent) -> void:
	if ev is InputEventMouseButton and ev.button_index == MOUSE_BUTTON_LEFT:
		if ev.pressed:
			_drag_win = win
			_drag_from = win.get_global_mouse_position() - win.position
			open(win)   # 置顶
		else:
			_drag_win = null
	elif ev is InputEventMouseMotion and _drag_win == win:
		win.position = win.get_global_mouse_position() - _drag_from