config.py

import secrets
import warnings
from typing import Annotated, Any, Literal

from pydantic import (
    AnyUrl,
    BeforeValidator,
    PostgresDsn,
    computed_field,
    model_validator,
)
from pydantic_core import MultiHostUrl
from pydantic_settings import BaseSettings, SettingsConfigDict
from typing_extensions import Self


def parse_cors(v: Any) -> list[str] | str:
    if isinstance(v, str) and not v.startswith("["):
        return [i.strip() for i in v.split(",")]
    elif isinstance(v, list | str):
        return v
    raise ValueError(v)


class Settings(BaseSettings):
    model_config = SettingsConfigDict(
        env_file=".env", env_ignore_empty=True, extra="ignore"
    )
    API_V1_STR: str = "/api/v1"
    SECRET_KEY: str = secrets.token_urlsafe(32)
    # 60 minutes * 24 hours * 8 days = 8 days
    ACCESS_TOKEN_EXPIRE_MINUTES: int = 60 * 24 * 8
    DOMAIN: str = "localhost"
    ENVIRONMENT: Literal["local", "staging", "production"] = "local"

    BACKEND_CORS_ORIGINS: Annotated[
        list[AnyUrl] | str, BeforeValidator(parse_cors)
    ] = []

    PROJECT_NAME: str
    EMAIL_TEST_USER: str = "test@example.com"

    POSTGRES_SERVER: str
    POSTGRES_PORT: int = 5432
    POSTGRES_USER: str
    POSTGRES_PASSWORD: str
    POSTGRES_DB: str = ""

    CELERY_BROKER_URL: str
    CELERY_RESULT_BACKEND: str

    @computed_field  # type: ignore[misc]
    @property
    def SQLALCHEMY_DATABASE_URI(self) -> PostgresDsn:
        return MultiHostUrl.build(
            scheme="postgresql+psycopg",
            username=self.POSTGRES_USER,
            password=self.POSTGRES_PASSWORD,
            host=self.POSTGRES_SERVER,
            port=self.POSTGRES_PORT,
            path=self.POSTGRES_DB,
        )

    FIRST_SUPERUSER: str
    FIRST_SUPERUSER_PASSWORD: str
    USERS_OPEN_REGISTRATION: bool = False

    AI_API_KEY: str | None = None
    AI_MODEL: str | None = None

    COLLECTION_GENERATION_PROMPT: str | None = None

    @computed_field  # type: ignore[prop-decorator]
    @property
    def ai_models_enabled(self) -> bool:
        return bool(self.AI_API_KEY and self.AI_MODEL)

    def _check_default_secret(self, var_name: str, value: str | None) -> None:
        if value == "changethis":
            message = (
                f'The value of {var_name} is "changethis", '
                "for security, please change it, at least for deployments."
            )
            if self.ENVIRONMENT == "local":
                warnings.warn(message, stacklevel=1)
            else:
                raise ValueError(message)

    @model_validator(mode="after")
    def _enforce_non_default_secrets(self) -> Self:
        self._check_default_secret("SECRET_KEY", self.SECRET_KEY)
        self._check_default_secret("POSTGRES_PASSWORD", self.POSTGRES_PASSWORD)
        self._check_default_secret(
            "FIRST_SUPERUSER_PASSWORD", self.FIRST_SUPERUSER_PASSWORD
        )

        return self


settings = Settings()  # type: ignore