Add direct-connect multiplayer foundation

network/network_profile_preferences.gd

@@ -0,0 +1,120 @@
+class_name NetworkProfilePreferences
+extends Node
+
+const FORMAT_VERSION: int = 1
+const PROFILE_PATH: String = "user://network_profile.json"
+const TEMP_PATH: String = "user://network_profile.json.tmp"
+const BACKUP_PATH: String = "user://network_profile.json.backup"
+
+var profile_id: String = ""
+var display_name: String = "Player"
+var created_at_unix: int = 0
+
+
+func load_or_create() -> bool:
+	_recover_interrupted_write()
+	if FileAccess.file_exists(PROFILE_PATH):
+		if _load_existing():
+			return true
+		var corrupt_path: String = (
+			"user://network_profile.corrupt.%d.json"
+			% int(Time.get_unix_time_from_system())
+		)
+		if not _rename(PROFILE_PATH, corrupt_path):
+			push_warning("Invalid network profile was preserved and not overwritten.")
+			return false
+	profile_id = Crypto.new().generate_random_bytes(16).hex_encode()
+	if profile_id.is_empty():
+		profile_id = "%d-%d" % [
+			int(Time.get_unix_time_from_system()),
+			Time.get_ticks_usec(),
+		]
+	display_name = "Player"
+	created_at_unix = int(Time.get_unix_time_from_system())
+	return _save_atomic()
+
+
+func _load_existing() -> bool:
+	var file := FileAccess.open(PROFILE_PATH, FileAccess.READ)
+	if file == null:
+		return false
+	var json := JSON.new()
+	var error: Error = json.parse(file.get_as_text())
+	file.close()
+	if error != OK or typeof(json.data) != TYPE_DICTIONARY:
+		return false
+	var data: Dictionary = json.data
+	if (
+		data.get("format_version") != FORMAT_VERSION
+		or typeof(data.get("profile_id")) != TYPE_STRING
+		or typeof(data.get("display_name")) != TYPE_STRING
+		or typeof(data.get("created_at_unix")) not in [TYPE_INT, TYPE_FLOAT]
+	):
+		return false
+	var loaded_id: String = data["profile_id"]
+	var loaded_name: String = data["display_name"]
+	if (
+		loaded_id.is_empty()
+		or loaded_id.length() > NetworkProtocol.MAX_PROFILE_ID_LENGTH
+		or loaded_name.is_empty()
+		or loaded_name.length() > NetworkProtocol.MAX_DISPLAY_NAME_LENGTH
+	):
+		return false
+	profile_id = loaded_id
+	display_name = loaded_name
+	created_at_unix = int(data["created_at_unix"])
+	return true
+
+
+func _save_atomic() -> bool:
+	var data: Dictionary = {
+		"format_version": FORMAT_VERSION,
+		"profile_id": profile_id,
+		"display_name": display_name,
+		"created_at_unix": created_at_unix,
+	}
+	var file := FileAccess.open(TEMP_PATH, FileAccess.WRITE)
+	if file == null:
+		return false
+	file.store_string(JSON.stringify(data, "\t"))
+	file.flush()
+	var error: Error = file.get_error()
+	file.close()
+	if error != OK:
+		_remove_if_present(TEMP_PATH)
+		return false
+	_remove_if_present(BACKUP_PATH)
+	var had_primary: bool = FileAccess.file_exists(PROFILE_PATH)
+	if had_primary and not _rename(PROFILE_PATH, BACKUP_PATH):
+		_remove_if_present(TEMP_PATH)
+		return false
+	if not _rename(TEMP_PATH, PROFILE_PATH):
+		if had_primary:
+			_rename(BACKUP_PATH, PROFILE_PATH)
+		return false
+	_remove_if_present(BACKUP_PATH)
+	return true
+
+
+func _recover_interrupted_write() -> void:
+	if FileAccess.file_exists(PROFILE_PATH):
+		_remove_if_present(TEMP_PATH)
+		_remove_if_present(BACKUP_PATH)
+		return
+	if FileAccess.file_exists(BACKUP_PATH):
+		_rename(BACKUP_PATH, PROFILE_PATH)
+	_remove_if_present(TEMP_PATH)
+
+
+func _rename(from_path: String, to_path: String) -> bool:
+	return DirAccess.rename_absolute(
+		ProjectSettings.globalize_path(from_path),
+		ProjectSettings.globalize_path(to_path)
+	) == OK
+
+
+func _remove_if_present(path: String) -> bool:
+	return (
+		not FileAccess.file_exists(path)
+		or DirAccess.remove_absolute(ProjectSettings.globalize_path(path)) == OK
+	)