from __future__ import annotations

from pathlib import Path

from app.utils.hashing import sha256_file


def test_two_files_with_same_content_share_sha(tmp_path: Path):
    a = tmp_path / "a.pdf"
    b = tmp_path / "b.pdf"
    payload = b"%PDF-1.4\n" + b"x" * 4096
    a.write_bytes(payload)
    b.write_bytes(payload)
    assert sha256_file(a) == sha256_file(b)


def test_one_byte_difference_changes_sha(tmp_path: Path):
    a = tmp_path / "a.pdf"
    b = tmp_path / "b.pdf"
    a.write_bytes(b"%PDF-1.4\n" + b"x" * 4096)
    b.write_bytes(b"%PDF-1.4\n" + b"x" * 4095 + b"y")
    assert sha256_file(a) != sha256_file(b)