# ShopUI (P8) —— NPC 商店窗。
#
#   var su := preload("res://ui/shop_ui.gd").new()
#   add_child(su)
#   su.setup(m2client, canvas_parent, proto, item_list)   # proto / item_list 可空
#
# `shop_opened(vid)` → 打开并列出货物（名字 + 价格 + [买]）。
# `shop_closed` → 关闭。`shop_error(kind)` → 顶部红字提示。
# 卖：inventory_ui 在商店开着时右键道具 → 调 shop_ui.sell(cell)。
extends Node

const SHOP_SLOT_COUNT := 40   # shop.SHOP_SLOT_COUNT (== SHOP_HOST_ITEM_MAX_NUM)

var client: Node
var proto: Node
var item_list  # ItemListDB (RefCounted)
var _root: Control
var _tabbar: HBoxContainer
var _list: VBoxContainer
var _err: Label
var _sell_quantity: SpinBox
var _active_tab := 0

func setup(m2client: Node, parent: Node, proto_node: Node = null, ilist: RefCounted = null) -> void:
	client = m2client
	proto = proto_node
	item_list = ilist
	_build(parent)
	if client.has_signal("shop_opened"):
		client.shop_opened.connect(func(_v): open())
	if client.has_signal("shop_closed"):
		client.shop_closed.connect(_close)
	if client.has_signal("shop_error"):
		client.shop_error.connect(_on_error)

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

func close() -> void:
	_close()

func open() -> void:
	_root.visible = true
	_err.text = ""
	_sell_quantity.value = 1
	_active_tab = 0
	refresh()

func _close() -> void:
	_root.visible = false
	_err.text = ""
	if _sell_quantity:
		_sell_quantity.value = 1

func close_and_leave() -> void:
	client.shop_close()
	_close()

func sell(inv_cell: int, count: int = -1) -> void:
	if not is_open() or inv_cell < 0:
		return
	var amount := count if count > 0 else int(_sell_quantity.value)
	amount = clampi(amount, 1, 200)
	if client.has_method("shop_sell") and not client.shop_sell(inv_cell, amount):
		_on_error("SEND_FAILED")

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 refresh() -> void:
	if not is_open() or client == null:
		return
	for c in _tabbar.get_children():
		_tabbar.remove_child(c)
		c.queue_free()
	for c in _list.get_children():
		_list.remove_child(c)
		c.queue_free()

	# START_EX 商店有多个货架（shop.GetTabCount）；普通 START 商店 tabs 只 1 个。
	var tabs: Array = []
	if client.has_method("get_shop"):
		tabs = client.get_shop().get("tabs", [])
	if tabs.is_empty():
		# 兼容没有 get_shop 的旧桩
		tabs = [{"name": "", "items": client.get_shop_items()}]
	_active_tab = clampi(_active_tab, 0, tabs.size() - 1)

	if tabs.size() > 1:
		_tabbar.visible = true
		for i in tabs.size():
			var tb := Button.new()
			tb.toggle_mode = true
			var tn := String(tabs[i].get("name", ""))
			tb.text = tn if tn != "" else "货架 %d" % (i + 1)
			tb.button_pressed = (i == _active_tab)
			var idx := i
			tb.pressed.connect(func() -> void:
				_active_tab = idx
				refresh())
			_tabbar.add_child(tb)
	else:
		_tabbar.visible = false

	var items: Array = tabs[_active_tab].get("items", [])
	if items.is_empty():
		var e := Label.new()
		e.text = "（无货物）"
		_list.add_child(e)
		return
	# uishop.py: 买位置 = tabIdx * SHOP_SLOT_COUNT + slotPos
	var base := _active_tab * SHOP_SLOT_COUNT
	for it in items:
		_list.add_child(_row(it, base))

func _row(it: Dictionary, pos_base := 0) -> Control:
	var row := HBoxContainer.new()
	row.custom_minimum_size = Vector2(320, 0)
	var nm := Label.new()
	nm.text = _name_of(int(it.get("vnum", 0)))
	nm.custom_minimum_size = Vector2(170, 0)
	nm.add_theme_font_size_override("font_size", 12)
	row.add_child(nm)
	var pr := Label.new()
	pr.text = "%d 金" % int(it.get("price", 0))
	pr.custom_minimum_size = Vector2(90, 0)
	pr.modulate = Color(0.95, 0.85, 0.5)
	row.add_child(pr)
	var buy := Button.new()
	buy.text = "买"
	var pos := pos_base + int(it.get("pos", 0))
	var stock := int(it.get("count", 0))
	var quantity := SpinBox.new()
	quantity.name = "Quantity"
	quantity.min_value = 1
	quantity.max_value = clampi(stock if stock > 0 else 200, 1, 200)
	quantity.step = 1
	quantity.value = 1
	quantity.custom_minimum_size = Vector2(64, 0)
	row.add_child(quantity)
	buy.pressed.connect(func() -> void:
		var amount := clampi(int(quantity.value), 1, int(quantity.max_value))
		if not client.shop_buy(pos, amount):
			_on_error("SEND_FAILED"))
	row.add_child(buy)
	return row

func _on_error(kind: String) -> void:
	var tbl := {
		"NOT_ENOUGH_MONEY": "金币不足",
		"SOLDOUT": "已售罄",
		"INVENTORY_FULL": "背包已满",
		"INVALID_POS": "位置无效",
		"NOT_ENOUGH_ITEM": "物品数量不足",
		"CANNOT_BUY": "当前物品不可购买",
		"CANNOT_SELL": "当前物品不可出售",
		"SHOP_BUSY": "商店正在处理上一笔交易",
		"SEND_FAILED": "交易请求发送失败",
	}
	_err.text = str(tbl.get(kind, kind))

func _build(parent: Node) -> void:
	_root = Control.new()
	_root.set_anchors_preset(Control.PRESET_CENTER)
	_root.position = Vector2(-190, -200)
	_root.size = Vector2(380, 400)
	_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(0.08, 0.07, 0.06, 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 = "商店"
	title.position = Vector2(12, 8)
	_root.add_child(title)
	_err = Label.new()
	_err.position = Vector2(60, 10)
	_err.modulate = Color(1, 0.4, 0.4)
	_err.add_theme_font_size_override("font_size", 12)
	_root.add_child(_err)
	var sell_hint := Label.new()
	sell_hint.text = "出售数量（背包右键）："
	sell_hint.position = Vector2(12, 360)
	sell_hint.add_theme_font_size_override("font_size", 11)
	_root.add_child(sell_hint)
	_sell_quantity = SpinBox.new()
	_sell_quantity.name = "SellQuantity"
	_sell_quantity.min_value = 1
	_sell_quantity.max_value = 200
	_sell_quantity.value = 1
	_sell_quantity.step = 1
	_sell_quantity.position = Vector2(160, 356)
	_sell_quantity.size = Vector2(70, 26)
	_root.add_child(_sell_quantity)
	_tabbar = HBoxContainer.new()
	_tabbar.position = Vector2(12, 30)
	_tabbar.add_theme_constant_override("separation", 4)
	_tabbar.visible = false
	_root.add_child(_tabbar)
	_list = VBoxContainer.new()
	_list.position = Vector2(12, 58)
	_list.add_theme_constant_override("separation", 4)
	_root.add_child(_list)
	var close_btn := Button.new()
	close_btn.text = "离开"
	close_btn.position = Vector2(300, 360)
	close_btn.pressed.connect(close_and_leave)
	_root.add_child(close_btn)