extends Control
class_name WalletUI
## Wallet & Transaction History UI panel.
##
## Displays:
## - Current Credit balance
## - Credit pack quick purchases (100, 500, 1000, 5000 CR)
## - Paged ledger transaction history with status/amounts/references
##
## docs/planning/economy.md US-6 (task 34c725431645).

signal back_requested

@onready var back_button: Button = $VBox/HeaderHBox/BackButton
@onready var refresh_button: Button = $VBox/HeaderHBox/RefreshButton
@onready var status_label: Label = $VBox/StatusLabel

@onready var balance_label: Label = $VBox/BalanceCard/Margin/HBox/BalanceLabel
@onready var buy_100_btn: Button = $VBox/BalanceCard/Margin/HBox/PacksHBox/Buy100Btn
@onready var buy_500_btn: Button = $VBox/BalanceCard/Margin/HBox/PacksHBox/Buy500Btn
@onready var buy_1000_btn: Button = $VBox/BalanceCard/Margin/HBox/PacksHBox/Buy1000Btn
@onready var buy_5000_btn: Button = $VBox/BalanceCard/Margin/HBox/PacksHBox/Buy5000Btn

@onready var tx_container: VBoxContainer = $VBox/LedgerSection/Scroll/TxList
@onready var prev_page_btn: Button = $VBox/LedgerSection/PagingHBox/PrevPageBtn
@onready var next_page_btn: Button = $VBox/LedgerSection/PagingHBox/NextPageBtn
@onready var page_label: Label = $VBox/LedgerSection/PagingHBox/PageLabel

var _api_client: Node = null
var current_page: int = 0
const PAGE_SIZE: int = 20
var total_tx_count: int = 0


func _ready() -> void:
	_api_client = _get_api()
	_wire_signals()
	if _api_client != null and _api_client.has_token():
		refresh_all()


func _get_api() -> Node:
	if has_node("/root/ApiClient"):
		return get_node("/root/ApiClient")
	return null


func _wire_signals() -> void:
	if back_button and not back_button.pressed.is_connected(_on_back_pressed):
		back_button.pressed.connect(_on_back_pressed)
	if refresh_button and not refresh_button.pressed.is_connected(refresh_all):
		refresh_button.pressed.connect(refresh_all)

	if buy_100_btn and not buy_100_btn.pressed.is_connected(_buy_pack.bind(100)):
		buy_100_btn.pressed.connect(_buy_pack.bind(100))
	if buy_500_btn and not buy_500_btn.pressed.is_connected(_buy_pack.bind(500)):
		buy_500_btn.pressed.connect(_buy_pack.bind(500))
	if buy_1000_btn and not buy_1000_btn.pressed.is_connected(_buy_pack.bind(1000)):
		buy_1000_btn.pressed.connect(_buy_pack.bind(1000))
	if buy_5000_btn and not buy_5000_btn.pressed.is_connected(_buy_pack.bind(5000)):
		buy_5000_btn.pressed.connect(_buy_pack.bind(5000))

	if prev_page_btn and not prev_page_btn.pressed.is_connected(_on_prev_page):
		prev_page_btn.pressed.connect(_on_prev_page)
	if next_page_btn and not next_page_btn.pressed.is_connected(_on_next_page):
		next_page_btn.pressed.connect(_on_next_page)


func _on_back_pressed() -> void:
	back_requested.emit()
	if get_tree() and get_tree().current_scene == self:
		get_tree().change_scene_to_file("res://scenes/main_menu.tscn")


func show_status(text: String, is_error: bool = false) -> void:
	if not status_label:
		return
	status_label.text = text
	if is_error:
		status_label.add_theme_color_override("font_color", Color(1.0, 0.3, 0.3))
	else:
		status_label.add_theme_color_override("font_color", Color(0.3, 0.9, 0.3))


func refresh_all() -> void:
	refresh_wallet()
	refresh_transactions()


func refresh_wallet() -> void:
	var api = _get_api()
	if not api or not api.has_token():
		return
	var res: Dictionary = await EconomyApiClient.get_wallet(api)
	if res.ok and res.data is Dictionary:
		var balance: int = int(res.data.get("balance", 0))
		if balance_label:
			balance_label.text = "%d Buffalo Chips" % balance
	else:
		show_status("Failed to fetch wallet: " + res.detail, true)


func refresh_transactions() -> void:
	var api = _get_api()
	if not api or not api.has_token():
		return
	var offset: int = current_page * PAGE_SIZE
	var res: Dictionary = await EconomyApiClient.get_wallet_transactions(api, PAGE_SIZE, offset)
	if res.ok and res.data is Dictionary:
		var items: Array = res.data.get("items", [])
		total_tx_count = int(res.data.get("total", 0))
		render_transactions(items)
		_update_paging_controls()
	else:
		show_status("Failed to fetch transactions: " + res.detail, true)


func _buy_pack(credits: int) -> void:
	var api = _get_api()
	if not api or not api.has_token():
		show_status("Please login to purchase Buffalo Chips", true)
		return
	show_status("Processing purchase of %d Buffalo Chips..." % credits)
	var res: Dictionary = await EconomyApiClient.purchase_credits(api, credits)
	if res.ok and res.data is Dictionary:
		var new_bal: int = int(res.data.get("new_balance", 0))
		if balance_label:
			balance_label.text = "%d Buffalo Chips" % new_bal
		show_status("Successfully purchased %d Buffalo Chips! Balance: %d Buffalo Chips" % [credits, new_bal])
		refresh_transactions()
	else:
		show_status("Purchase failed: " + res.detail, true)


func render_transactions(tx_list: Array) -> void:
	if not tx_container:
		return
	for c in tx_container.get_children():
		tx_container.remove_child(c)
		c.queue_free()

	if tx_list.is_empty():
		var empty_lbl := Label.new()
		empty_lbl.text = "No transactions found."
		empty_lbl.add_theme_color_override("font_color", Color(0.6, 0.6, 0.6))
		tx_container.add_child(empty_lbl)
		return

	for tx in tx_list:
		if not tx is Dictionary:
			continue
		var row := PanelContainer.new()
		var hbox := HBoxContainer.new()
		hbox.add_theme_constant_override("separation", 12)
		row.add_child(hbox)

		var date_str: String = str(tx.get("created_at", ""))
		if date_str.length() > 19:
			date_str = date_str.substr(0, 19).replace("T", " ")
		var date_lbl := Label.new()
		date_lbl.text = date_str
		date_lbl.custom_minimum_size = Vector2(140, 0)
		date_lbl.add_theme_color_override("font_color", Color(0.7, 0.7, 0.7))
		hbox.add_child(date_lbl)

		var type_lbl := Label.new()
		type_lbl.text = str(tx.get("type", "")).replace("_", " ").capitalize()
		type_lbl.custom_minimum_size = Vector2(160, 0)
		hbox.add_child(type_lbl)

		var amount: int = int(tx.get("amount", 0))
		var amt_lbl := Label.new()
		if amount > 0:
			amt_lbl.text = "+%d Buffalo Chips" % amount
			amt_lbl.add_theme_color_override("font_color", Color(0.2, 0.9, 0.2))
		else:
			amt_lbl.text = "%d Buffalo Chips" % amount
			amt_lbl.add_theme_color_override("font_color", Color(0.9, 0.3, 0.3))
		amt_lbl.custom_minimum_size = Vector2(100, 0)
		hbox.add_child(amt_lbl)

		var bal_lbl := Label.new()
		bal_lbl.text = "Bal: %s Buffalo Chips" % str(tx.get("balance_after", 0))
		bal_lbl.custom_minimum_size = Vector2(100, 0)
		bal_lbl.add_theme_color_override("font_color", Color(0.8, 0.8, 0.8))
		hbox.add_child(bal_lbl)

		var ref_lbl := Label.new()
		var ref_type: String = str(tx.get("reference_type", ""))
		var ref_id: String = str(tx.get("reference_id", ""))
		if ref_type != "":
			ref_lbl.text = "%s #%s" % [ref_type, ref_id]
		else:
			ref_lbl.text = "-"
		ref_lbl.size_flags_horizontal = Control.SIZE_EXPAND_FILL
		ref_lbl.add_theme_color_override("font_color", Color(0.5, 0.5, 0.5))
		hbox.add_child(ref_lbl)

		tx_container.add_child(row)


func _update_paging_controls() -> void:
	var total_pages: int = int(ceil(float(total_tx_count) / float(PAGE_SIZE)))
	if total_pages < 1:
		total_pages = 1
	if page_label:
		page_label.text = "Page %d of %d" % [current_page + 1, total_pages]
	if prev_page_btn:
		prev_page_btn.disabled = current_page <= 0
	if next_page_btn:
		next_page_btn.disabled = current_page >= total_pages - 1


func _on_prev_page() -> void:
	if current_page > 0:
		current_page -= 1
		refresh_transactions()


func _on_next_page() -> void:
	var total_pages: int = int(ceil(float(total_tx_count) / float(PAGE_SIZE)))
	if current_page < total_pages - 1:
		current_page += 1
		refresh_transactions()