from functools import lru_cache
from typing import Literal

from pydantic import AnyHttpUrl, Field, computed_field
from pydantic_settings import BaseSettings, SettingsConfigDict


class Settings(BaseSettings):
    model_config = SettingsConfigDict(env_file=".env", env_file_encoding="utf-8", extra="ignore")

    app_name: str = "NexaMFA"
    environment: Literal["dev", "test", "prod"] = "dev"
    public_base_url: AnyHttpUrl = "https://mfa.example.com"
    cors_origins: str = "http://localhost:5173"

    database_url: str = "postgresql+asyncpg://nexamfa:nexamfa@postgres:5432/nexamfa"
    redis_url: str = "redis://redis:6379/0"

    admin_token: str = Field(default="change-me-admin-token")
    oidc_issuer: str = "https://mfa.example.com"
    oidc_client_id: str = "authentik"
    oidc_client_secret: str = "change-me-oidc-secret"
    oidc_redirect_uris: str = "https://authentik.example.com/application/o/nexamfa/callback/"
    oidc_signing_key_pem: str | None = None

    challenge_ttl_seconds: int = 60
    enrollment_ttl_seconds: int = 600
    access_token_ttl_seconds: int = 300
    auth_code_ttl_seconds: int = 120
    rate_limit_default: str = "120/minute"
    rate_limit_approve: str = "12/minute"

    fcm_project_id: str | None = None
    fcm_service_account_json: str | None = None

    @computed_field
    @property
    def cors_origin_list(self) -> list[str]:
        return [origin.strip() for origin in self.cors_origins.split(",") if origin.strip()]

    @computed_field
    @property
    def oidc_redirect_uri_list(self) -> list[str]:
        return [uri.strip() for uri in self.oidc_redirect_uris.split(",") if uri.strip()]


@lru_cache
def get_settings() -> Settings:
    return Settings()