"""Targeted content hashing for duplicate candidates."""

import hashlib
from pathlib import Path
from typing import Iterable


def sha256_file(path: Path, chunk_size: int = 1024 * 1024) -> str:
    digest = hashlib.sha256()
    with path.open("rb") as source:
        for chunk in iter(lambda: source.read(chunk_size), b""):
            digest.update(chunk)
    return digest.hexdigest()


def compare_audio_files(paths: Iterable[Path]) -> dict:
    paths = tuple(paths)
    if len(paths) < 2:
        raise ValueError("At least two files are required for comparison")
    fingerprints = []
    for path in paths:
        fingerprints.append(
            {
                "path": str(path),
                "size": path.stat().st_size,
                "sha256": sha256_file(path),
            }
        )
    identical = len({item["sha256"] for item in fingerprints}) == 1
    return {
        "status": "identical" if identical else "different",
        "files": fingerprints,
    }