#  Pyrogram - Telegram MTProto API Client Library for Python
#  Copyright (C) 2017-2020 Dan <https://github.com/delivrance>
#
#  This file is part of Pyrogram.
#
#  Pyrogram is free software: you can redistribute it and/or modify
#  it under the terms of the GNU Lesser General Public License as published
#  by the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  Pyrogram is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU Lesser General Public License for more details.
#
#  You should have received a copy of the GNU Lesser General Public License
#  along with Pyrogram.  If not, see <http://www.gnu.org/licenses/>.

import os
import random
import unittest

import tgcrypto


class TestIGE256Input(unittest.TestCase):
    TYPE_ERROR_PATTERN = r"'\w+' does not (support|have) the buffer interface|a bytes-like object is required, not '\w+'"

    def test_ige256_encrypt_invalid_args_count(self):
        with self.assertRaisesRegex(TypeError, r"function takes exactly \d arguments \(\d given\)"):
            tgcrypto.ige256_encrypt(os.urandom(16), os.urandom(32))

    def test_ige256_encrypt_invalid_args_type(self):
        with self.assertRaisesRegex(TypeError, self.TYPE_ERROR_PATTERN):
            tgcrypto.ige256_encrypt(1, 2, 3)

    def test_ige256_encrypt_empty_data(self):
        with self.assertRaisesRegex(ValueError, r"Data must not be empty"):
            tgcrypto.ige256_encrypt(b"", os.urandom(32), os.urandom(32))

    def test_ige256_encrypt_invalid_key_size(self):
        with self.assertRaisesRegex(ValueError, r"Key size must be exactly 32 bytes"):
            tgcrypto.ige256_encrypt(os.urandom(16), os.urandom(31), os.urandom(32))

    def test_ige256_encrypt_invalid_iv_size(self):
        with self.assertRaisesRegex(ValueError, r"IV size must be exactly 32 bytes"):
            tgcrypto.ige256_encrypt(os.urandom(16), os.urandom(32), os.urandom(31))

    def test_ige256_decrypt_invalid_args_count(self):
        with self.assertRaisesRegex(TypeError, r"function takes exactly \d arguments \(\d given\)"):
            tgcrypto.ige256_decrypt(os.urandom(16), os.urandom(32))

    def test_ige256_decrypt_invalid_args_type(self):
        with self.assertRaisesRegex(TypeError, self.TYPE_ERROR_PATTERN):
            tgcrypto.ige256_decrypt(1, 2, 3)

    def test_ige256_decrypt_empty_data(self):
        with self.assertRaisesRegex(ValueError, r"Data must not be empty"):
            tgcrypto.ige256_decrypt(b"", os.urandom(32), os.urandom(32))

    def test_ige256_decrypt_invalid_key_size(self):
        with self.assertRaisesRegex(ValueError, r"Key size must be exactly 32 bytes"):
            tgcrypto.ige256_decrypt(os.urandom(16), os.urandom(31), os.urandom(32))

    def test_ige256_decrypt_invalid_iv_size(self):
        with self.assertRaisesRegex(ValueError, r"IV size must be exactly 32 bytes"):
            tgcrypto.ige256_decrypt(os.urandom(16), os.urandom(32), os.urandom(31))


class TestIGE256Random(unittest.TestCase):
    DATA_CHUNK_MAX_SIZE = 64
    KEY_SIZE = 32
    IV_SIZE = 32

    TESTS_AMOUNT = 500

    TEMPLATE = """
    def test_ige256_random_{mode1}_{count}(self):
        data = {data}
        key = {key}
        iv = {iv}
        
        a = tgcrypto.ige256_{mode1}(data, key, iv)
        b = tgcrypto.ige256_{mode2}(a, key, iv)
        
        self.assertEqual(data, b)
    """.replace("\n    ", "\n")

    for count in range(TESTS_AMOUNT):
        exec(
            TEMPLATE.format(
                mode1="encrypt",
                mode2="decrypt",
                count=count,
                data=os.urandom(random.randint(1, DATA_CHUNK_MAX_SIZE) * 16),
                key=os.urandom(KEY_SIZE),
                iv=os.urandom(IV_SIZE),
            )
        )

    for count in range(TESTS_AMOUNT):
        exec(
            TEMPLATE.format(
                mode1="decrypt",
                mode2="encrypt",
                count=count,
                data=os.urandom(random.randint(1, DATA_CHUNK_MAX_SIZE) * 16),
                key=os.urandom(KEY_SIZE),
                iv=os.urandom(IV_SIZE),
            )
        )


if __name__ == "__main__":
    unittest.main()