from typing import Union
from time import time
import kasten


def _packer(block_data: bytes, **kasten_header) -> kasten.main.KastenPacked:
    def __get_optional(key, default):
        try:
            return kasten_header[key]
        except KeyError:
            return default
    # Todo: validate length sanities
    return kasten.generator.pack.pack(
        block_data,
        kasten_header['type'],
        kasten_header['encrypt mode'],
        __get_optional('signer', b''),
        __get_optional('signature', b''),
        __get_optional('metadata', {}),
        int(time()//60 * 60)
        )


# Block creation functions handle calling the proof and compiling blocks
# They do not handle sigs or encryption (at least never directly)

def create_block_anonymous_vdf(
        rounds: int, block_data: Union[str, bytes], **block_header):
    # Block with anonymous VDF as proof
    packed = _packer(block_data, **block_header)
    return kasten.generator.KastenMimcGenerator.generate(
        packed, rounds)