from typing import List

from operations import ffAdd, ffMultiply
from globals import Nb
from util import transpose, matrix_element, matrix_index, print_debug, debug_get_round, bytearray_to_str, block_bytes

sbox = [
    [0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76],
    [0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0],
    [0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15],
    [0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75],
    [0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84],
    [0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf],
    [0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8],
    [0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2],
    [0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73],
    [0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb],
    [0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79],
    [0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08],
    [0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a],
    [0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e],
    [0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf],
    [0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16]]


def subBytes(state: bytearray):
    for i, byte in enumerate(state):
        h1 = byte >> 4
        h2 = byte & 0xf
        state[i] = sbox[h1][h2]


def shiftRows(state: bytearray, rotate=False) -> bytearray:
    if rotate:
        state = transpose(state)
    for row in range(Nb):
        r = state[row * Nb:row * Nb + Nb]
        for i in range(row):
            r_temp = r[0]
            r = r[1:Nb]
            r.append(r_temp)
        state[row * Nb: row * Nb + Nb] = r
    if rotate:
        state = transpose(state)
    return state


# nb: number of bytes in each row
def mixColumns(state: bytearray, rotate=False) -> bytearray:
    out = state.copy()
    if rotate:
        out = transpose(out)
    for col in range(Nb):
        m0 = matrix_element(out, col, 0)
        m1 = matrix_element(out, col, 1)
        m2 = matrix_element(out, col, 2)
        m3 = matrix_element(out, col, 3)
        s0 = ffMultiply(0x02, m0) ^ ffMultiply(0x03, m1) ^ m2 ^ m3
        s1 = m0 ^ ffMultiply(0x02, m1) ^ ffMultiply(0x03, m2) ^ m3
        s2 = m0 ^ m1 ^ ffMultiply(0x02, m2) ^ ffMultiply(0x03, m3)
        s3 = ffMultiply(0x03, m0) ^ m1 ^ m2 ^ ffMultiply(0x02, m3)

        # set the new byte values in the state
        out[matrix_index(col, 0)] = s0
        out[matrix_index(col, 1)] = s1
        out[matrix_index(col, 2)] = s2
        out[matrix_index(col, 3)] = s3
    if rotate:
        out = transpose(out)
    return out


def addRoundKey(state: bytearray, key: bytearray):
    for i, byte in enumerate(state):
        state[i] = ffAdd(byte, key[i])


def cipher(b_in: bytearray, key_schedule: List[bytearray], nr: int, debug: bool = False) -> bytearray:
    if debug:
        print("CIPHER (ENCRYPT):")
        print_debug(debug_get_round(0) + "input", bytearray_to_str(b_in))
    state = b_in.copy()
    key = block_bytes(key_schedule, rotate=(not debug))
    if debug:
        print_debug(debug_get_round(0) + "k_sch", bytearray_to_str(key[0]))
    addRoundKey(state, key[0])
    for r in range(1, nr):
        if debug:
            print_debug(debug_get_round(r) + "start", bytearray_to_str(state))
        subBytes(state)
        if debug:
            print_debug(debug_get_round(r) + "s_box", bytearray_to_str(state))
        state = shiftRows(state, rotate=debug)
        if debug:
            print_debug(debug_get_round(r) + "s_row", bytearray_to_str(state))
        state = mixColumns(state, rotate=debug)
        if debug:
            print_debug(debug_get_round(r) + "m_col", bytearray_to_str(state))
            print_debug(debug_get_round(r) + "k_sch", bytearray_to_str(key[r]))
        addRoundKey(state, key[r])

    if debug:
        print_debug(debug_get_round(nr) + "start", bytearray_to_str(state))
    subBytes(state)
    if debug:
        print_debug(debug_get_round(nr) + "s_box", bytearray_to_str(state))
    state = shiftRows(state, rotate=debug)
    if debug:
        print_debug(debug_get_round(nr) + "s_row", bytearray_to_str(state))
        print_debug(debug_get_round(nr) + "k_sch", bytearray_to_str(key[-1]))
    addRoundKey(state, key[-1])
    if debug:
        print_debug(debug_get_round(nr) + "output", bytearray_to_str(state))
        print()
    return state


# subBytes test
test_bytes = bytearray([0x19, 0xa0, 0x9a, 0xe9,
                        0x3d, 0xf4, 0xc6, 0xf8,
                        0xe3, 0xe2, 0x8d, 0x48,
                        0xbe, 0x2b, 0x2a, 0x08])
expected = bytearray([0xd4, 0xe0, 0xb8, 0x1e,
                      0x27, 0xbf, 0xb4, 0x41,
                      0x11, 0x98, 0x5d, 0x52,
                      0xae, 0xf1, 0xe5, 0x30])
subBytes(test_bytes)
# print_bytes(test_bytes)
assert test_bytes == expected

# shiftRows test
test_bytes = bytearray([0xd4, 0xe0, 0xb8, 0x1e,
                        0x27, 0xbf, 0xb4, 0x41,
                        0x11, 0x98, 0x5d, 0x52,
                        0xae, 0xf1, 0xe5, 0x30])
expected = bytearray([0xd4, 0xe0, 0xb8, 0x1e,
                      0xbf, 0xb4, 0x41, 0x27,
                      0x5d, 0x52, 0x11, 0x98,
                      0x30, 0xae, 0xf1, 0xe5])
test_bytes = shiftRows(test_bytes)
# print_bytes(test_bytes)
assert test_bytes == expected

# mixColums test
test_bytes = bytearray([0xd4, 0xe0, 0xb8, 0x1e,
                        0xbf, 0xb4, 0x41, 0x27,
                        0x5d, 0x52, 0x11, 0x98,
                        0x30, 0xae, 0xf1, 0xe5])
expected = bytearray([0x04, 0xe0, 0x48, 0x28,
                      0x66, 0xcb, 0xf8, 0x06,
                      0x81, 0x19, 0xd3, 0x26,
                      0xe5, 0x9a, 0x7a, 0x4c])
test_bytes = mixColumns(test_bytes)
# print_bytes(test_bytes)
assert test_bytes == expected

# addRoundKey test
test_bytes = bytearray([0x04, 0xe0, 0x48, 0x28,
                        0x66, 0xcb, 0xf8, 0x06,
                        0x81, 0x19, 0xd3, 0x26,
                        0xe5, 0x9a, 0x7a, 0x4c])
expected = bytearray([0xa4, 0x68, 0x6b, 0x02,
                      0x9c, 0x9f, 0x5b, 0x6a,
                      0x7f, 0x35, 0xea, 0x50,
                      0xf2, 0x2b, 0x43, 0x49])
key = bytearray([0xa0, 0x88, 0x23, 0x2a,
                 0xfa, 0x54, 0xa3, 0x6c,
                 0xfe, 0x2c, 0x39, 0x76,
                 0x17, 0xb1, 0x39, 0x05])
addRoundKey(test_bytes, key)
assert test_bytes == expected

