from __future__ import annotations

from enum import Enum
import json
from pathlib import Path
from typing import Optional

from jose.constants import ALGORITHMS
from passlib.context import CryptContext
from peewee import Database, SqliteDatabase
from pydantic import BaseModel, Field

DB = SqliteDatabase("tmp/vpn.db")
PRODUCTION_MODE = False

# to get a string like this run:
# openssl rand -hex 32
SECRET_KEY = "2f7875b0d2be8a76eba8077ab4d9f8b1c749e02647e9ac9e0f909c3acbfc9856"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30

CRYPT_CONTEXT = CryptContext(schemes=["bcrypt"], deprecated="auto")


class DBType(Enum):
    sqlite = "sqlite"
    mysql = "mysql"


class DBConfig(BaseModel):
    db_type: DBType = DBType.sqlite

    @property
    def database(self) -> Database:
        return SqliteDatabase("tmp/vpn.db")


class JWTConfig(BaseModel):
    secret: Optional[str] = None
    hash_algorithm: str = ALGORITHMS.HS256
    expiry_minutes: int = 30


class CryptoConfig(BaseModel):
    schemes: list[str] = ["bcrypt"]

    @property
    def cryptContext(self) -> CryptContext:
        return CryptContext(schemes=self.schemes, deprecated="auto")


class BaseConfig(BaseModel):
    db: DBConfig = Field(default_factory=DBConfig)
    jwt: JWTConfig = Field(default_factory=JWTConfig)
    crypto: CryptoConfig = Field(default_factory=CryptoConfig)

    def save(self, filename: Path) -> None:
        with open(filename, "w") as kv:
            kv.write(self.json(indent=2))


CONFIG_FILE = "tmp/config.json"


async def get_default_config() -> BaseConfig:
    return BaseConfig()


async def is_configured() -> bool:
    return Path(CONFIG_FILE).is_file()


async def get_config() -> BaseConfig:
    with open(CONFIG_FILE, "r") as kv:
        return BaseConfig.parse_obj(json.load(kv))