# 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

var client: Node
var proto: Node
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 := {}

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

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

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
	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 = ""
	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 refresh() -> void:
	if client == null:
		return
	var x: Dictionary = client.get_exchange()
	if not x.get("active", false):
		_root.visible = false
		_next_display = 0
		_offered_cells.clear()
		_gold_input.text = ""
		_status.text = ""
		return
	_root.visible = true
	_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)
	_accept_btn.text = "已接受 ✓" if me else "接受"
	_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"
	_status.text = ""

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.add_theme_font_size_override("font_size", 12)
		box.add_child(l)

func _on_put_gold() -> void:
	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 > 2000000000:
		_status.text = "金币数量必须在 1～2000000000 之间"
		return
	if client.exchange_add_gold(g):
		_gold_input.text = ""
		_status.text = ""
	else:
		_status.text = "金币请求发送失败"

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_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)
	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(func() -> void: client.exchange_accept())
	bottom.add_child(_accept_btn)
	var cancel := Button.new()
	cancel.text = "取消"
	cancel.pressed.connect(func() -> void: client.exchange_cancel())
	bottom.add_child(cancel)