extends ConfirmationDialog

## Presentation only: listing never reconciles, migrates or deletes packages.
## New package names use OS crypto, independently of every simulation RNG.
signal new_slot_requested(path: String, display_name: String)
signal load_slot_requested(path: String)
const LayerSkin := preload("res://scripts/ui/layer_interface_skin.gd")
const OWNED_NAME_PATTERN := "^manual_ui_[0-9a-f]{32}$"
var _directory := ""
var _mode := ""
var _new_path := ""
var _new_name := ""
var _message: Label
var _slots: ItemList
var _rows: Array[Dictionary] = []

func _ready() -> void:
	name = "ManualSaveSlotsDialog"
	cancel_button_text = "戻る"
	var column := VBoxContainer.new()
	column.custom_minimum_size = Vector2(460, 220)
	add_child(column)
	_message = Label.new()
	_message.name = "ManualSaveSlotsMessage"
	_message.custom_minimum_size.x = 460
	_message.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	column.add_child(_message)
	_slots = ItemList.new()
	_slots.name = "ManualSaveSlotsList"
	_slots.custom_minimum_size = Vector2(460, 150)
	_slots.size_flags_vertical = Control.SIZE_EXPAND_FILL
	_slots.item_selected.connect(_select_slot)
	column.add_child(_slots)
	confirmed.connect(_confirm_choice)
	canceled.connect(_clear_choice)
	close_requested.connect(_clear_choice)
	apply_layer_skin(LayerSkin.active_layer(self))

func show_new_save(current_path: String) -> void:
	_clear_choice()
	_mode = "new"
	_directory = current_path.get_base_dir()
	title = "旧保存を残して新しく保存"
	ok_button_text = "新しく保存"
	_slots.hide()
	# No directory is created until the player explicitly confirms.
	var token: PackedByteArray = Crypto.new().generate_random_bytes(16)
	if token.size() == 16:
		_new_path = _directory.path_join("manual_ui_" + token.hex_encode())
	_new_name = "手動保存 " + Time.get_datetime_string_from_system(false, true)
	var fresh: bool = not _new_path.is_empty() and is_fresh_slot(_new_path)
	get_ok_button().disabled = not fresh
	_message.text = "今の進行は、元の保存とは別に保存します。\n元の保存は残り、あとから読込一覧で選べます。\n\n" + _new_name if fresh else "新しい保存先を用意できませんでした。\n元の保存は変更していません。"
	popup_centered(Vector2i(520, 300))
	get_cancel_button().grab_focus()

func show_load_slots(current_path: String) -> void:
	_clear_choice()
	_mode = "load"
	_directory = current_path.get_base_dir()
	title = "保存スロットを選んで読込"
	ok_button_text = "選んで読込"
	_message.text = "読み込む保存を選んでください。\n現在の未保存の進行は、選んだ保存で置き換わります。"
	_slots.show()
	_slots.clear()
	_rows = read_slot_rows(_directory)
	var selection := -1
	for index: int in range(_rows.size()):
		var row: Dictionary = _rows[index]
		_slots.add_item(row[&"label"])
		_slots.set_item_disabled(index, not row[&"loadable"])
		if row[&"path"] == current_path and row[&"loadable"]:
			selection = index
	if selection < 0:
		for index: int in range(_rows.size()):
			if _rows[index][&"loadable"]:
				selection = index
				break
	get_ok_button().disabled = selection < 0
	if selection >= 0:
		_slots.select(selection)
	else:
		_message.text = "読み込める保存が見つかりません。\n保存データは変更していません。"
	popup_centered(Vector2i(520, 360))
	if selection >= 0: _slots.grab_focus()
	else: get_cancel_button().grab_focus()

static func is_owned_slot_name(value: String) -> bool:
	if value == "manual_ui": return true
	var pattern := RegEx.new()
	return pattern.compile(OWNED_NAME_PATTERN) == OK and pattern.search(value) != null

static func is_fresh_slot(path: String) -> bool:
	if not path.begins_with("user://") or not is_owned_slot_name(path.get_file()) or path.get_file() == "manual_ui": return false
	# Reject any existing package, transaction, recovery family, file or link.
	for suffix: String in ["", ".tmp", ".bak", SaveService.MIGRATION_BACKUP_SUFFIX, SaveService.SAVE_TRANSACTION_SUFFIX]:
		var absolute: String = ProjectSettings.globalize_path(path + suffix)
		var parent: DirAccess = DirAccess.open(absolute.get_base_dir())
		if FileAccess.file_exists(absolute) or DirAccess.dir_exists_absolute(absolute) or (parent != null and parent.is_link(absolute.get_file())): return false
	return true

static func read_slot_rows(directory: String) -> Array[Dictionary]:
	var rows: Array[Dictionary] = []
	if not directory.begins_with("user://"): return rows
	var source: DirAccess = DirAccess.open(directory)
	if source == null: return rows
	var names: PackedStringArray = source.get_directories()
	names.sort()
	for slot: String in names:
		if not is_owned_slot_name(slot) or source.is_link(slot): continue
		var path: String = directory.path_join(slot)
		# Manifest text alone is never authority for a loadable package.
		var inspected: Dictionary = SaveService.inspect_snapshot(path)
		var loadable: bool = bool(inspected.get(&"ok", false))
		var label: String = "手動保存（最初のスロット）" if slot == "manual_ui" else "手動保存"
		if loadable:
			label = String(inspected.get(&"manifest", {}).get("display_name", label))
		else:
			label += " — 読込不可（保存は残っています）"
		label = "%d. %s" % [rows.size() + 1, label]
		rows.append({&"path": path, &"label": label, &"loadable": loadable})
	return rows

func _select_slot(index: int) -> void:
	get_ok_button().disabled = index < 0 or index >= _rows.size() or not _rows[index][&"loadable"]

func _confirm_choice() -> void:
	if _mode == "new" and is_fresh_slot(_new_path):
		new_slot_requested.emit(_new_path, _new_name)
	elif _mode == "load":
		var selected: PackedInt32Array = _slots.get_selected_items()
		if selected.size() == 1 and selected[0] >= 0 and selected[0] < _rows.size() and _rows[selected[0]][&"loadable"]:
			load_slot_requested.emit(_rows[selected[0]][&"path"])
	_clear_choice()

func _clear_choice() -> void:
	_mode = ""
	_new_path = ""
	_new_name = ""
	_rows.clear()

func apply_layer_skin(layer: int) -> void:
	if _message != null: LayerSkin.register_text(_message, layer)
	LayerSkin.apply_tree(self, layer)