"""Application configuration.

Twelve-factor: everything is read from the environment. Defaults are
development-friendly; production supplies real values via the compose `.env`.
No secrets or endpoints are hard-coded.
"""

from functools import lru_cache

from pydantic import 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 = "Provenance"
    version: str = "0.0.0"
    app_env: str = Field(default="development", description="development | production")

    # SQLAlchemy async URL, e.g. postgresql+asyncpg://user:pass@host:5432/db
    database_url: str = Field(
        default="postgresql+asyncpg://provenance:provenance@localhost:5432/provenance",
    )

    # --- Auth / sessions ---
    session_ttl_days: int = 30
    token_ttl_hours: int = 24  # email-verify / password-reset token lifetime
    cookie_name: str = "provenance_session"
    cookie_secure: bool = True  # set false for local http; true behind TLS
    # Base URL used to build links in outbound email.
    app_base_url: str = "http://localhost"

    # --- Email (SMTP) ---
    mailer: str = Field(default="console", description="console | smtp")
    smtp_host: str | None = None
    smtp_port: int = 587
    smtp_username: str | None = None
    smtp_password: str | None = None
    smtp_from: str = "Provenance <no-reply@provenance.local>"


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