"""Streams uploaded documents from arbitrary S3 buckets to local disk (ADR-0060).

Uploaded files live across many source buckets (each `uploaded_files` row
carries its own `s3_file_bucket`), so — unlike the bucket-bound `S3Client` —
this takes the bucket per call. Downloading to a file (rather than reading the
object into memory) keeps a single multi-GB member off the heap when it is added
to the on-disk ZIP.
"""

from __future__ import annotations

from typing import Any


class S3DocumentDownloader:
    def __init__(self, boto_s3_client: Any) -> None:
        self._client = boto_s3_client

    def download(self, bucket: str, key: str, dest_path: str) -> None:
        self._client.download_file(Bucket=bucket, Key=key, Filename=dest_path)