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(f'{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(f'{SystemState.__get_state_path()}/system.json')

    @staticmethod
    def save(system_state):

        system_state_file_contents = f'{system_state.to_json(indent=4)}\n'
        os.makedirs(SystemState.__get_state_path(), exist_ok=True, mode=0o700)

        system_state_file_path = f'{SystemState.__get_state_path()}/system.json'
        Path(system_state_file_path).touch(exist_ok=True, mode=0o600)

        with open(system_state_file_path, 'w') as system_state_file:

            system_state_file.write(system_state_file_contents)
            system_state_file.close()

    @staticmethod
    def dissolve():

        system_state = SystemState.get()

        if system_state is not None:

            system_state_path = f'{SystemState.__get_state_path()}/system.json'
            pathlib.Path.unlink(Path(system_state_path), missing_ok=True)

    @staticmethod
    def __get_state_path():
        return Constants.HV_STATE_HOME