## Separate-screen panel displaying the prestige buff graph.
## Tiles are placed manually in the scene editor — each PrestigeBuffGraphTile has its PrestigeBuffNode
## resource assigned directly. The panel manages the prestige currency balance display and
## delegates connection-line drawing to a PrestigeBuffConnectionOverlay child.
class_name PrestigeBuffGraphPanel
extends PanelContainer

@onready var _balance_label: Label = $MarginContainer/VBoxContainer/BalanceLabel
@onready var _tiles_area: Control = $MarginContainer/VBoxContainer/TilesArea
@onready var _close_button: Button = $MarginContainer/VBoxContainer/Header/CloseButton
@onready var _connection_overlay: PrestigeBuffConnectionOverlay = $MarginContainer/VBoxContainer/TilesArea/ConnectionOverlay

var _game_state: LevelGameState


func _ready() -> void:
	_game_state = find_parent("LevelGameState")
	if _game_state == null:
		push_error("PrestigeBuffGraphPanel: Could not find LevelGameState parent")
		return

	_game_state.currency_changed.connect(_on_currency_changed)
	_close_button.pressed.connect(_on_close_pressed)

	visibility_changed.connect(_on_visibility_changed)
	_refresh_balance()


## Rebuilds the connection overlay by scanning all PrestigeBuffGraphTile children and matching parent_ids.
func _refresh_connections() -> void:
	if _connection_overlay == null:
		return

	var tiles_by_id: Dictionary = {}
	var all_tiles: Array[PrestigeBuffGraphTile] = []
	_collect_tiles(_tiles_area, all_tiles)

	for tile in all_tiles:
		var node_id: StringName = tile.get_node_id()
		if node_id != &"":
			tiles_by_id[node_id] = tile

	var connections: Array = []
	for tile in all_tiles:
		if tile.prestige_buff == null:
			continue
		for parent_id in tile.prestige_buff.parent_ids:
			var parent_tile: PrestigeBuffGraphTile = tiles_by_id.get(parent_id, null)
			if parent_tile:
				connections.append([parent_tile, tile])

	_connection_overlay.set_connections(connections)


## Collects all PrestigeBuffGraphTile nodes rooted at `from`, recursing into every child.
func _collect_tiles(from: Node, out_tiles: Array[PrestigeBuffGraphTile]) -> void:
	var found: Array[Node] = from.find_children("*", "PrestigeBuffGraphTile", true, false)
	for node in found:
		var tile := node as PrestigeBuffGraphTile
		if tile:
			out_tiles.append(tile)

func _refresh_balance() -> void:
	if _game_state == null:
		_balance_label.text = "Prestige Currency: 0"
		return

	var currency_id: StringName = _game_state.get_prestige_currency_id()
	var balance: BigNumber = _game_state.get_currency_amount_by_id(currency_id)
	_balance_label.text = "Prestige Currency: %s" % balance.to_string_suffix(2)

func _on_currency_changed(currency_id: StringName, _new_amount: BigNumber) -> void:
	if currency_id == _game_state.get_prestige_currency_id():
		_refresh_balance()

func _on_close_pressed() -> void:
	hide()

func _on_visibility_changed() -> void:
	if visible:
		_refresh_balance()
		_refresh_connections()

func _on_prestige_buff_toggle_pressed() -> void:
	show()