"""Unit tests for `runner.helpers.fdr_reader.archive_size_bytes`.

The full `iter_records` parser is owned by AZ-441; AZ-406 only commits to
the directory-size helper.
"""

from __future__ import annotations

from pathlib import Path

import pytest

from runner.helpers.fdr_reader import archive_size_bytes


def test_archive_size_zero_for_missing_root(tmp_path: Path) -> None:
    assert archive_size_bytes(tmp_path / "does-not-exist") == 0


def test_archive_size_sums_nested_files(tmp_path: Path) -> None:
    # Arrange
    (tmp_path / "a").mkdir()
    (tmp_path / "a" / "b.bin").write_bytes(b"x" * 100)
    (tmp_path / "a" / "c.bin").write_bytes(b"y" * 50)
    (tmp_path / "top.bin").write_bytes(b"z" * 200)
    # Act
    size = archive_size_bytes(tmp_path)
    # Assert
    assert size == 350


def test_iter_records_raises_until_az441_lands() -> None:
    """Until AZ-441 fills the parser in, callers must see a clear error."""
    from runner.helpers.fdr_reader import iter_records

    with pytest.raises(NotImplementedError, match="AZ-441"):
        next(iter_records(Path("/tmp/nonexistent")))