from typing import Optional
import os
import logging
log = logging.getLogger("rc.lststor")


class DiskStoredList:
	__file: Optional[str] = None
	__items: Optional[list] = None

	def __init__(self, file: str):
		# file does not have to exist, but parent directory does
		if not os.path.exists(file):
			if not os.path.isdir(os.path.dirname(file)):
				raise NotADirectoryError(f"Parent directory for file {file} does not exist!")

		self.__file = file
		self.__items = []

		if os.path.exists(file):
			self._load_from_file()

	def _load_from_file(self):
		log.debug(f"DiskStoredList: loading")
		with open(self.__file, 'r') as f:
			for line in f.readlines():
				line = line.strip()
				if len(line):
					self.__items.append(line)
		log.debug(f"DiskStoredList: loaded {len(self.__items)}")


	def append(self, line: str):
		with open(self.__file, 'a') as f:
			log.debug(f"DiskStoredList: append {line}")
			self.__items.append(line)
			f.write(f"{line}\n")

	def count(self):
		return len(self.__items)

	def __contains__(self, line: str) -> bool:
		log.debug(f"DiskStoredList: contains? {line}")
		return line in self.__items

	def __iter__(self):
		return self.__items.__iter__()

	def __len__(self):
		return len(self.__items)