import base64
import hashlib

from Crypto.Cipher import AES, DES3, PKCS1_v1_5
from Crypto.Hash import SHA1
from Crypto.PublicKey import RSA
from Crypto.Signature import pkcs1_15
from Crypto.Util.Padding import pad, unpad
from sanic import Sanic


def md5(orig: bytes) -> bytes:
    h = hashlib.md5()
    h.update(orig)
    return bytes.fromhex(h.hexdigest())



def base64_decode(b64: str) -> bytes:
    return base64.b64decode(b64)

def base64_encode(orig: bytes) -> str:
    return base64.b64encode(orig).decode()



def get_rsa_privkey():
    with open(Sanic.get_app().config["PRIVKEY_PATH"], "r") as f:
        return f.read()

def rsa_decrypt(cipher_text: bytes, private_key: str) -> bytes:
    cipher = PKCS1_v1_5.new(RSA.importKey(private_key)) 
    return cipher.decrypt(cipher_text, b"rsa")

def rsa_encrypt(origin_text: bytes, private_key: str) -> bytes:
    cipher = PKCS1_v1_5.new(RSA.importKey(private_key)) 
    return cipher.encrypt(origin_text)

def rsa_sha1_sign(message: bytes, private_key: str) -> bytes:
    key = RSA.import_key(private_key)
    h = SHA1.new(message)
    return pkcs1_15.new(key).sign(h)



def des3_decrypt(cipher_text: bytes, key: bytes) -> bytes:
    cipher = DES3.new(key, DES3.MODE_ECB)
    return cipher.decrypt(cipher_text)
    # return unpad(cipher.decrypt(cipher_text), 16)

def des3_encrypt(origin_text: bytes, key: bytes) -> bytes:
    cipher = DES3.new(key, DES3.MODE_ECB)
    return cipher.encrypt(pad(origin_text, 16))



def aes_cbc_decrypt(cipher_text: bytes, key: bytes) -> bytes:
    cipher = AES.new(key, AES.MODE_CBC)
    return unpad(cipher.decrypt(cipher_text), 16)

def aes_cbc_encrypt(origin_text: bytes, key: bytes) -> bytes:
    cipher = AES.new(key, AES.MODE_CBC)
    return cipher.encrypt(pad(origin_text, 16))



def xor(a: bytes, b: bytes) -> bytes:
    return bytes([ i ^ j for (i, j) in zip(bytearray(a), bytearray(b)) ])