from core.Constants import Constants
from dataclasses import dataclass
from dataclasses_json import dataclass_json
from json import JSONDecodeError
from pathlib import Path
import json
import os
import pathlib

@dataclass_json
@dataclass
class SystemState:
    profile_id: int

    @staticmethod
    def get():

        try:
            system_state_file_contents = open(SystemState._get_state_path() + '/system.json', 'r').read()
        except FileNotFoundError:
            return None

        try:
            system_state = json.loads(system_state_file_contents)
        except JSONDecodeError:
            return None

        # noinspection PyUnresolvedReferences
        return SystemState.from_dict(system_state)

    @staticmethod
    def exists():
        return os.path.isfile(SystemState._get_state_path() + '/system.json')

    @staticmethod
    def save(system_state):

        system_state_file_contents = system_state.to_json(indent=4) + '\n'
        os.makedirs(SystemState._get_state_path(), exist_ok=True, mode=0o700)

        system_state_file_path = SystemState._get_state_path() + '/system.json'
        Path(system_state_file_path).touch(exist_ok=True, mode=0o600)

        text_io_wrapper = open(system_state_file_path, 'w')
        text_io_wrapper.write(system_state_file_contents)

    @staticmethod
    def dissolve():

        system_state = SystemState.get()

        if system_state is not None:

            system_state_path = SystemState._get_state_path() + '/system.json'
            pathlib.Path.unlink(Path(system_state_path), missing_ok=True)

    @staticmethod
    def _get_state_path():
        return Constants.SP_STATE_HOME