from cryptography_s_des_exploring.sdes.keys import generate_subkeys
from cryptography_s_des_exploring.sdes.sdes import apply_table, function, IP, s0, expansion, s1, IP_inv
from cryptography_s_des_exploring.sdes.blocks import decode, decode_bytes


def decrypt_block(key: str, block: str):
    """
    Encrypt the 8-bit block with 10-bit key.

    key is a binary which represented with a 10 character string.
    block is a binary which represented with 8 character string.
    """

    key1, key2 = generate_subkeys(key)

    temp = apply_table(block, IP)
    temp = function(expansion, s0, s1, key2, temp)
    temp = temp[4:] + temp[:4]
    temp = function(expansion, s0, s1, key1, temp)
    plaintext = apply_table(temp, IP_inv)

    return plaintext


def decrypt(key: str, message: str):
    """
    Encrypt the message with the 10-bit key.
    The message is split into 8-bit blocks.

    key is a binary which represented with a 10 character string.
    """

    decoded = decode_bytes(message)

    decrypted = list(map(lambda b: decrypt_block(key, b), decoded))

    return decode(decrypted)