"""The multi-bucket document downloader (ADR-0060) — streams object bytes from
whichever source bucket an uploaded file lives in, to local disk."""

from collections.abc import Iterator
from pathlib import Path

import pytest
from moto import mock_aws

from infrastructure.s3.s3_document_downloader import S3DocumentDownloader
from tests.infrastructure import make_boto_client


@pytest.fixture
def downloader() -> Iterator[S3DocumentDownloader]:
    with mock_aws():
        boto_client = make_boto_client("s3")
        boto_client.create_bucket(Bucket="src-a")
        boto_client.create_bucket(Bucket="src-b")
        boto_client.put_object(Bucket="src-a", Key="surveys/one.pdf", Body=b"AAA")
        boto_client.put_object(Bucket="src-b", Key="photos/two.zip", Body=b"BBB")
        yield S3DocumentDownloader(boto_client)


def test_downloads_bytes_from_the_named_source_bucket(
    downloader: S3DocumentDownloader, tmp_path: Path
) -> None:
    # act — each object streams from its own bucket to a local file.
    a = tmp_path / "a"
    b = tmp_path / "b"
    downloader.download("src-a", "surveys/one.pdf", str(a))
    downloader.download("src-b", "photos/two.zip", str(b))

    # assert
    assert a.read_bytes() == b"AAA"
    assert b.read_bytes() == b"BBB"