async def create(conn):
    # Users core table
    await conn.execute(
        """
        CREATE TABLE IF NOT EXISTS User (
            id INTEGER PRIMARY KEY,
            email TEXT NOT NULL UNIQUE,
            display_name TEXT NOT NULL,
            profile_photo_url TEXT
        );
        """
    )

    # Local credential storage for password auth
    await conn.execute(
        """
        CREATE TABLE IF NOT EXISTS LocalCredentials (
            user_id INTEGER PRIMARY KEY,
            hashed_password TEXT NOT NULL,
            FOREIGN KEY(user_id) REFERENCES User(id) ON DELETE CASCADE
        );
        """
    )

    # OAuth provider links (e.g., Google)
    await conn.execute(
        """
        CREATE TABLE IF NOT EXISTS OAuthCredentials (
            user_id INTEGER NOT NULL,
            provider TEXT NOT NULL,
            provider_user_id TEXT NOT NULL,
            PRIMARY KEY (provider, provider_user_id),
            FOREIGN KEY(user_id) REFERENCES User(id) ON DELETE CASCADE
        );
        """
    )

    # Helpful indices
    await conn.execute("CREATE INDEX IF NOT EXISTS idx_user_email ON User(email);")


async def get_by_email(conn, email: str):
    async with conn.execute(
        "SELECT id, email, display_name, profile_photo_url FROM User WHERE email = ? LIMIT 1",
        (email,),
    ) as c:
        row = await c.fetchone()
        if not row:
            return None
        from users.models import User

        return User(id=int(row[0]), email=row[1], display_name=row[2], profile_photo_url=row[3])


async def get_by_id(conn, user_id: int):
    async with conn.execute(
        "SELECT id, email, display_name, profile_photo_url FROM User WHERE id = ? LIMIT 1",
        (user_id,),
    ) as c:
        row = await c.fetchone()
        if not row:
            return None
        from users.models import User

        return User(id=int(row[0]), email=row[1], display_name=row[2], profile_photo_url=row[3])


async def get_by_ids(conn, ids: list[int]):
    if not ids:
        return {}
    placeholders = ",".join(["?"] * len(ids))
    results: dict[int, "User"] = {}
    async with conn.execute(
        f"SELECT id, email, display_name, profile_photo_url FROM User WHERE id IN ({placeholders})",
        list(ids),
    ) as c:
        async for row in c:
            from users.models import User

            u = User(id=int(row[0]), email=row[1], display_name=row[2], profile_photo_url=row[3])
            results[u.id] = u
    return results


async def insert_user(conn, email: str, display_name: str, profile_photo_url: str | None = None):
    async with conn.execute(
        "INSERT INTO User (email, display_name, profile_photo_url) VALUES (?, ?, ?)",
        (email, display_name, profile_photo_url),
    ) as cur:
        user_id = cur.lastrowid
    return user_id


async def set_local_credentials(conn, user_id: int, hashed_password: str):
    await conn.execute(
        "INSERT OR REPLACE INTO LocalCredentials (user_id, hashed_password) VALUES (?, ?)",
        (user_id, hashed_password),
    )


async def get_local_password_hash(conn, user_id: int) -> str | None:
    async with conn.execute(
        "SELECT hashed_password FROM LocalCredentials WHERE user_id = ?",
        (user_id,),
    ) as c:
        row = await c.fetchone()
        return row[0] if row else None