# ExchangeUI (P8) —— 交易 / 换货窗。
#
#   var xu := preload("res://ui/exchange_ui.gd").new()
#   add_child(xu)
#   xu.setup(m2client, canvas_parent, proto)   # proto 可空
#
# 两栏：我方 / 对方，各列道具行 + 金币。底部：金币输入 + [放金币]、[接受]、[取消]。
# `exchange_changed` 刷新（active=false 时自动关闭）。
# inventory_ui 在交易开着时右键道具 → 调 xu.offer(win, cell)。
extends Node

const ItemTooltip = preload("res://ui/item_tooltip.gd")

var client: Node
var proto: Node
var _tooltip_builder: RefCounted
var _root: Control
var _self_box: VBoxContainer
var _peer_box: VBoxContainer
var _self_gold: Label
var _peer_gold: Label
var _status: Label
var _accept_btn: Button
var _gold_input: LineEdit
var _next_display := 0
var _offered_cells := {}
var _self_grid: GridContainer
var _exchange_cells: Dictionary = {}
var item_mouse: Node
var _mobile_mode := false
var _mobile_inventory_scroll: ScrollContainer
var _mobile_inventory_list: VBoxContainer

const EXCHANGE_SLOT_COUNT := 12
const INVENTORY_WINDOW := 1
const EXCHANGE_LIMIT_RANGE := 1000.0
const ITEM_ANTIFLAG_GIVE := 1 << 13

var _accept_pending := false
var _anchor := Vector2.ZERO
var _anchor_valid := false

# EXCHANGE_GC_ALREADY / LESS_GOLD 的线上的子头值（服务器 exchange.cpp）。
# GC_END 在成功与取消两种结局都会发，成败文案只走 CHAT_TYPE_INFO 聊天通道。
const NOTICE_ALREADY := 6
const NOTICE_LESS_GOLD := 7
var _was_active := false
var _notice_shown := false
var _end_note: Label
var _end_note_timer: Timer

func setup(m2client: Node, parent: Node, proto_node: Node = null) -> void:
	client = m2client
	proto = proto_node
	_tooltip_builder = ItemTooltip.new()
	_tooltip_builder.setup(AssetRoot.path(), "en", proto)
	_build(parent)
	if client.has_signal("exchange_changed"):
		client.exchange_changed.connect(refresh)

func is_open() -> bool:
	return _root != null and _root.visible

func get_mobile_window() -> Control:
	return _root

func set_mobile_mode(enabled: bool) -> void:
	_mobile_mode = enabled
	if _root:
		_apply_mobile_layout()
		_refresh_mobile_inventory()

func close() -> void:
	if item_mouse and item_mouse.has_method("unregister_owner"):
		item_mouse.unregister_owner(self)
		if item_mouse.has_method("is_attached") and item_mouse.is_attached():
			item_mouse.cancel()
	if _root:
		_root.visible = false
	_next_display = 0
	_offered_cells.clear()
	_accept_pending = false
	_anchor_valid = false
	if _gold_input:
		_gold_input.text = ""

func offer(inv_window: int, inv_cell: int) -> void:
	if not is_open() or inv_window < 0 or inv_cell < 0:
		return
	var key := "%d:%d" % [inv_window, inv_cell]
	if _offered_cells.has(key):
		_status.text = "该物品已经放入交易"
		return
	if not _can_give(_item_at(inv_window, inv_cell)):
		return
	var x: Dictionary = client.get_exchange()
	var used := {}
	for item in x.get("self_items", []):
		used[int(item.get("slot", -1))] = true
	for i in 12:
		if not used.has(i):
			_next_display = i
			break
	if used.size() >= 12:
		_status.text = "交易物品栏已满"
		return
	if client.exchange_add_item(inv_window, inv_cell, _next_display):
		_offered_cells[key] = true
		_next_display = (_next_display + 1) % 12
		_status.text = ""
		_refresh_mobile_inventory()
	else:
		_status.text = "交易请求发送失败"

func _name_of(vnum: int) -> String:
	if proto and proto.has_method("item"):
		var d: Dictionary = proto.item(vnum)
		var n := String(d.get("locale_name", d.get("name", "")))
		if n != "":
			return n
	return "#%d" % vnum

func _tooltip_for(item: Dictionary) -> String:
	var vnum := int(item.get("vnum", 0))
	if _tooltip_builder:
		var pd: Dictionary = proto.item(vnum) if proto and proto.has_method("item") else {}
		return _tooltip_builder.format(vnum, int(item.get("count", 1)), pd, item)
	return "%s\n#%d ×%d" % [_name_of(vnum), vnum, int(item.get("count", 1))]

func refresh() -> void:
	if client == null:
		return
	var x: Dictionary = client.get_exchange()
	if not x.get("active", false):
		if _was_active:
			# 窗口开着时服务器关掉了交易（成功或取消，二者同发 GC_END）。
			_show_end_note(int(x.get("notice", 0)))
		_was_active = false
		_notice_shown = false
		_root.visible = false
		_next_display = 0
		_offered_cells.clear()
		_accept_pending = false
		_anchor_valid = false
		_gold_input.text = ""
		_status.text = ""
		return
	_was_active = true
	_root.visible = true
	_capture_anchor()
	_render_self_grid(x.get("self_items", []))
	_fill(_self_box, x.get("self_items", []))
	_fill(_peer_box, x.get("peer_items", []))
	_self_gold.text = "金币: %d" % int(x.get("self_gold", 0))
	_peer_gold.text = "金币: %d" % int(x.get("peer_gold", 0))
	var me := bool(x.get("self_accept", false))
	var peer := bool(x.get("peer_accept", false))
	# The server clears self_accept when either side changes the offer.  Do not
	# invent a local transaction state: mirror the authoritative bit exactly.
	_accept_pending = me
	_accept_btn.text = "已接受 ✓" if me else "接受"
	_accept_btn.disabled = me
	_accept_btn.modulate = Color(0.5, 1, 0.5) if me else Color(1, 1, 1)
	_root.get_node("PeerAccept").text = "对方: 已接受" if peer else "对方: 未接受"
	var notice := int(x.get("notice", 0))
	if notice != 0 and not _notice_shown:
		_notice_shown = true
		_status.text = _notice_text(notice)
	else:
		_status.text = ""
	_refresh_mobile_inventory()

func _notice_text(code: int) -> String:
	match code:
		NOTICE_ALREADY:
			return "对方已经在交易中"
		NOTICE_LESS_GOLD:
			return "金币不足"
	return ""

# 交易被服务器关闭时的一条短暂浮动提示（成败详情以 CHAT_TYPE_INFO 聊天为准）。
func _show_end_note(code: int) -> void:
	if _root == null or _root.get_parent() == null:
		return
	if _end_note == null:
		_end_note = Label.new()
		_end_note.add_theme_font_size_override("font_size", 15)
		_end_note.set_anchors_preset(Control.PRESET_CENTER_TOP)
		_end_note.position = Vector2(-110, 130)
		_end_note.size = Vector2(220, 24)
		_end_note.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		_root.get_parent().add_child(_end_note)
		_end_note_timer = Timer.new()
		_end_note_timer.one_shot = true
		_end_note_timer.timeout.connect(func(): if _end_note: _end_note.visible = false)
		add_child(_end_note_timer)
	var extra := _notice_text(code)
	_end_note.text = ("交易结束（%s）" % extra) if extra != "" else "交易结束，结果见聊天提示"
	_end_note.visible = true
	_end_note_timer.start(5.0)

func _apply_mobile_layout() -> void:
	if _root == null:
		return
	if _mobile_mode:
		# The inventory candidate list is part of the same hosted surface, so it
		# scales and receives the same safe-area treatment as the trade window.
		_root.size = Vector2(688, 400)
		_root.position = Vector2(-344, -200)
		if _mobile_inventory_scroll:
			_mobile_inventory_scroll.position = Vector2(452, 54)
			_mobile_inventory_scroll.size = Vector2(224, 280)
			_mobile_inventory_scroll.visible = true
	else:
		_root.size = Vector2(440, 360)
		_root.position = Vector2(-220, -180)
		if _mobile_inventory_scroll:
			_mobile_inventory_scroll.position = Vector2.ZERO
			_mobile_inventory_scroll.size = Vector2.ZERO
			_mobile_inventory_scroll.visible = false

func _refresh_mobile_inventory() -> void:
	if not _mobile_mode or _mobile_inventory_list == null or not is_open():
		return
	for child in _mobile_inventory_list.get_children():
		child.queue_free()
	var inventory: Array = client.get_inventory() if client and client.has_method("get_inventory") else []
	var shown := 0
	for item in inventory:
		var cell := int(item.get("cell", -1))
		var vnum := int(item.get("vnum", 0))
		if cell < 0 or vnum <= 0:
			continue
		if _offered_cells.has("%d:%d" % [INVENTORY_WINDOW, cell]):
			continue
		var button := Button.new()
		button.alignment = HORIZONTAL_ALIGNMENT_LEFT
		button.text = "%s ×%d  · 点按加入" % [_name_of(vnum), int(item.get("count", 1))]
		button.custom_minimum_size = Vector2(214, 34)
		button.tooltip_text = _tooltip_for(item)
		var captured_cell := cell
		button.pressed.connect(func() -> void: offer(INVENTORY_WINDOW, captured_cell))
		_mobile_inventory_list.add_child(button)
		shown += 1
	if shown == 0:
		var empty := Label.new()
		empty.text = "（没有可交易物品）"
		empty.add_theme_font_size_override("font_size", 12)
		_mobile_inventory_list.add_child(empty)

func _item_at(inv_window: int, inv_cell: int) -> Dictionary:
	if client == null:
		return {}
	if client.has_method("get_item"):
		var direct: Dictionary = client.get_item(inv_window, inv_cell)
		if not direct.is_empty():
			return direct
	if inv_window == INVENTORY_WINDOW and client.has_method("get_inventory"):
		for item in client.get_inventory():
			if int(item.get("cell", -1)) == inv_cell:
				return item
	if inv_window == 2 and client.has_method("get_equipment"):
		var equipment: Array = client.get_equipment()
		if inv_cell >= 0 and inv_cell < equipment.size():
			return equipment[inv_cell]
	return {}

func _can_give(item_data: Dictionary) -> bool:
	var vnum := int(item_data.get("vnum", 0))
	var proto_data: Dictionary = proto.item(vnum) if proto and proto.has_method("item") else {}
	var flags := int(item_data.get("anti_flags", 0)) | int(proto_data.get("anti_flags", 0))
	if (flags & ITEM_ANTIFLAG_GIVE) != 0:
		_status.text = "该物品不可交易"
		return false
	return true

func _render_self_grid(rows: Array) -> void:
	if _self_grid == null:
		return
	for pos in _exchange_cells:
		var cell: Button = _exchange_cells[pos]
		cell.text = ""
		cell.tooltip_text = ""
		cell.set_meta("vnum", 0)
		cell.set_meta("count", 0)
	for row in rows:
		var pos := int(row.get("slot", -1))
		if not _exchange_cells.has(pos):
			continue
		var vnum := int(row.get("vnum", 0))
		var count := int(row.get("count", 1))
		var cell: Button = _exchange_cells[pos]
		cell.text = "%s%s" % [_name_of(vnum).substr(0, 6), (" ×%d" % count) if count > 1 else ""]
		cell.tooltip_text = _tooltip_for(row)
		cell.set_meta("vnum", vnum)
		cell.set_meta("count", count)

func _drop_to_slot(payload: Dictionary, display_pos: int) -> bool:
	if payload.is_empty() or display_pos < 0 or display_pos >= EXCHANGE_SLOT_COUNT:
		return false
	if bool(payload.get("money", false)):
		if int(client.get_exchange().get("self_gold", 0)) > 0:
			_status.text = "金币已经放入，不能修改"
			return false
		var amount := int(payload.get("count", 0))
		if amount <= 0 or not client.has_method("exchange_add_gold"):
			return false
		return client.exchange_add_gold(amount)
	var source_window := int(payload.get("window", -1))
	var source_cell := int(payload.get("cell", -1))
	if source_window not in [INVENTORY_WINDOW, 2] or source_cell < 0:
		return false
	var item_data := payload.duplicate(true)
	var source_data := _item_at(source_window, source_cell)
	for key in source_data:
		if not item_data.has(key):
			item_data[key] = source_data[key]
	if not _can_give(item_data):
		return false
	for row in client.get_exchange().get("self_items", []):
		if int(row.get("slot", -1)) == display_pos:
			return false
	var key := "%d:%d" % [source_window, source_cell]
	if _offered_cells.has(key):
		return false
	if not client.has_method("exchange_add_item") or not client.exchange_add_item(
			source_window, source_cell, display_pos):
		_status.text = "交易请求发送失败"
		return false
	_offered_cells[key] = true
	_refresh_mobile_inventory()
	return true

func _fill(box: VBoxContainer, rows: Array) -> void:
	for c in box.get_children():
		c.queue_free()
	for r in rows:
		var l := Label.new()
		l.text = "%s ×%d" % [_name_of(int(r.get("vnum", 0))), int(r.get("count", 1))]
		l.tooltip_text = _tooltip_for(r)
		l.add_theme_font_size_override("font_size", 12)
		box.add_child(l)

func _on_put_gold() -> void:
	var current := int(client.get_exchange().get("self_gold", 0))
	if current > 0:
		_status.text = "金币已经放入，不能修改"
		return
	var raw := _gold_input.text.strip_edges()
	if raw == "" or not raw.is_valid_int():
		_status.text = "请输入有效金币数量"
		return
	var g := int(raw)
	if g <= 0 or g > 9999999:
		_status.text = "金币数量必须在 1～9999999 之间"
		return
	if client.has_method("exchange_add_gold") and client.exchange_add_gold(g):
		_gold_input.text = ""
		_status.text = ""
	else:
		_status.text = "金币请求发送失败"

func _on_accept() -> void:
	if _accept_pending or _accept_btn.disabled:
		return
	if client.has_method("exchange_accept") and client.exchange_accept():
		_accept_pending = true
		_accept_btn.disabled = true
	else:
		_status.text = "接受请求发送失败"

func _on_cancel() -> void:
	if client and client.has_method("exchange_cancel"):
		client.exchange_cancel()
	close()

func _capture_anchor() -> void:
	if _anchor_valid or client == null or not client.has_method("get_main_vid") \
			or not client.has_method("get_entity"):
		return
	var entity: Dictionary = client.get_entity(int(client.get_main_vid()))
	var p = entity.get("pos_cm", null)
	if p is Vector3:
		_anchor = Vector2(p.x, p.y)
		_anchor_valid = true
	elif entity.has("x") and entity.has("y"):
		_anchor = Vector2(float(entity.get("x", 0)), float(entity.get("y", 0)))
		_anchor_valid = true

func _current_position() -> Variant:
	if client == null or not client.has_method("get_main_vid") or not client.has_method("get_entity"):
		return null
	var entity: Dictionary = client.get_entity(int(client.get_main_vid()))
	var p = entity.get("pos_cm", null)
	if p is Vector3:
		return Vector2(p.x, p.y)
	if entity.has("x") and entity.has("y"):
		return Vector2(float(entity.get("x", 0)), float(entity.get("y", 0)))
	return null

func _process(_dt: float) -> void:
	if not is_open() or not _anchor_valid:
		return
	var current = _current_position()
	if current is Vector2 and (absf(current.x - _anchor.x) > EXCHANGE_LIMIT_RANGE \
			or absf(current.y - _anchor.y) > EXCHANGE_LIMIT_RANGE):
		if client.has_method("exchange_cancel"):
			client.exchange_cancel()
		close()

func _build(parent: Node) -> void:
	_root = Control.new()
	_root.set_anchors_preset(Control.PRESET_CENTER)
	_root.position = Vector2(-220, -180)
	_root.size = Vector2(440, 360)
	_root.visible = false
	_root.set_meta("is_titlebar", true)
	parent.add_child(_root)
	var panel := Panel.new()
	panel.set_anchors_preset(Control.PRESET_FULL_RECT)
	var sb := StyleBoxFlat.new()
	sb.bg_color = Color(0.07, 0.08, 0.1, 0.97)
	sb.set_corner_radius_all(4)
	panel.add_theme_stylebox_override("panel", sb)
	_root.add_child(panel)
	var title := Label.new()
	title.text = "交易"
	title.position = Vector2(12, 8)
	_root.add_child(title)

	var sl := Label.new()
	sl.text = "我方"
	sl.position = Vector2(20, 34)
	_root.add_child(sl)
	_self_box = VBoxContainer.new()
	_self_box.position = Vector2(20, 56)
	_self_box.custom_minimum_size = Vector2(200, 0)
	_root.add_child(_self_box)
	_self_grid = GridContainer.new()
	_self_grid.columns = 6
	_self_grid.position = Vector2(20, 138)
	_self_grid.add_theme_constant_override("h_separation", 3)
	_self_grid.add_theme_constant_override("v_separation", 3)
	_root.add_child(_self_grid)
	for pos in EXCHANGE_SLOT_COUNT:
		var cell := Button.new()
		cell.custom_minimum_size = Vector2(52, 32)
		cell.add_theme_font_size_override("font_size", 8)
		_self_grid.add_child(cell)
		_exchange_cells[pos] = cell
		if item_mouse and item_mouse.has_method("register_target"):
			item_mouse.register_target(cell,
				func(payload: Dictionary): return _drop_to_slot(payload, pos), self)
	_self_gold = Label.new()
	_self_gold.text = "金币: 0"
	_self_gold.position = Vector2(20, 250)
	_root.add_child(_self_gold)

	var pl := Label.new()
	pl.text = "对方"
	pl.position = Vector2(240, 34)
	_root.add_child(pl)
	_peer_box = VBoxContainer.new()
	_peer_box.position = Vector2(240, 56)
	_peer_box.custom_minimum_size = Vector2(180, 0)
	_root.add_child(_peer_box)
	_peer_gold = Label.new()
	_peer_gold.text = "金币: 0"
	_peer_gold.position = Vector2(240, 250)
	_root.add_child(_peer_gold)
	_status = Label.new()
	_status.position = Vector2(20, 276)
	_status.add_theme_font_size_override("font_size", 11)
	_status.add_theme_color_override("font_color", Color(1, 0.65, 0.55))
	_root.add_child(_status)

	var pa := Label.new()
	pa.name = "PeerAccept"
	pa.text = "对方: 未接受"
	pa.position = Vector2(240, 272)
	pa.add_theme_font_size_override("font_size", 12)
	_root.add_child(pa)

	var bottom := HBoxContainer.new()
	bottom.position = Vector2(20, 310)
	_root.add_child(bottom)
	_gold_input = LineEdit.new()
	_gold_input.placeholder_text = "金币"
	_gold_input.custom_minimum_size = Vector2(90, 0)
	# Godot will open the native numeric keyboard on Android/iOS while the
	# validation below remains authoritative for desktop and hardware keyboards.
	_gold_input.virtual_keyboard_type = LineEdit.KEYBOARD_TYPE_NUMBER
	bottom.add_child(_gold_input)
	var put := Button.new()
	put.text = "放金币"
	put.pressed.connect(_on_put_gold)
	bottom.add_child(put)
	_accept_btn = Button.new()
	_accept_btn.text = "接受"
	_accept_btn.pressed.connect(_on_accept)
	bottom.add_child(_accept_btn)
	var cancel := Button.new()
	cancel.text = "取消"
	cancel.pressed.connect(_on_cancel)
	bottom.add_child(cancel)

	_mobile_inventory_scroll = ScrollContainer.new()
	_mobile_inventory_scroll.name = "MobileInventory"
	_mobile_inventory_scroll.visible = false
	_mobile_inventory_list = VBoxContainer.new()
	_mobile_inventory_list.add_theme_constant_override("separation", 4)
	_mobile_inventory_scroll.add_child(_mobile_inventory_list)
	_root.add_child(_mobile_inventory_scroll)
	_apply_mobile_layout()