"""Utility helpers for uploaded VCF payload decoding."""

from __future__ import annotations

import gzip


def decode_uploaded_vcf_bytes(file_name: str, raw_bytes: bytes) -> str:
    """Decode uploaded VCF bytes, supporting optional gzip compression."""
    if file_name.lower().endswith(".gz"):
        return gzip.decompress(raw_bytes).decode("utf-8", errors="replace")
    return raw_bytes.decode("utf-8", errors="replace")