"""SQLite persistence for encrypted enrollment templates."""

import os
from pathlib import Path

from sqlalchemy import LargeBinary, String, create_engine
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, sessionmaker

DATABASE_URL = os.environ.get(
    "SIGVERIFY_DATABASE_URL",
    f"sqlite:///{(Path(__file__).resolve().parents[1] / 'data' / 'signatures.sqlite3').as_posix()}",
)
engine = create_engine(
    DATABASE_URL,
    connect_args={"check_same_thread": False} if DATABASE_URL.startswith("sqlite") else {},
)
SessionLocal = sessionmaker(bind=engine, expire_on_commit=False)


class Base(DeclarativeBase):
    """Declarative base for API database tables."""


class SignatureTemplate(Base):
    """An encrypted sample belonging to one claimed user identity."""

    __tablename__ = "signature_templates"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    user_id: Mapped[str] = mapped_column(String(200), index=True)
    encrypted_payload: Mapped[bytes] = mapped_column(LargeBinary)


def initialize_database() -> None:
    """Create missing tables and ensure the SQLite data directory exists."""
    if DATABASE_URL.startswith("sqlite:///"):
        Path(DATABASE_URL.removeprefix("sqlite:///")).parent.mkdir(parents=True, exist_ok=True)
    Base.metadata.create_all(engine)