import hashlib

import click


def is_correct_hash(value):
    return all(map(lambda c: c in "0123456789abcdef", value.lower())) and len(
        value
    ) in [32, 40, 64, 128]


class Hash(click.ParamType):
    """ParamType accepting hashes"""

    def convert(self, value, param, ctx):
        if not is_correct_hash(value):
            self.fail(
                "'%s' is not correct MD5/SHA1/SHA256/SHA512 hash" % value, param, ctx
            )
        return value.lower()


class HashFile(click.File):
    name = "file_or_hash"
    """ParamType accepting hashes or evaluating SHA256 for provided file"""

    def __init__(self):
        # We shouldn't want to parametrize this
        super(HashFile, self).__init__(mode="rb")

    def convert(self, value, param, ctx):
        if is_correct_hash(value):
            return value.lower()
        f = super(HashFile, self).convert(value, param, ctx)
        return hashlib.sha256(f.read()).hexdigest()