import hashlib
from pathlib import Path


class IntegrityChecker:
    """
    Класс для проверки целостности файлов по хэш-сумме.
    """

    def calculate_hash(self, file_path: str) -> str:
        hasher = hashlib.sha256()
        with open(file_path, "rb") as f:
            for chunk in iter(lambda: f.read(4096), b""):
                hasher.update(chunk)
        return hasher.hexdigest()

    def save_hash(self, file_path: str, hash_file: str) -> None:
        file_hash = self.calculate_hash(file_path)
        Path(hash_file).write_text(file_hash, encoding="utf-8")

    def verify_hash(self, file_path: str, hash_file: str) -> bool:
        if not Path(hash_file).exists():
            return False
        expected = Path(hash_file).read_text(encoding="utf-8").strip()
        actual = self.calculate_hash(file_path)
        return expected == actual