# Copyright 2021 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Tests that keys are consistently accepted or rejected in all languages."""

from typing import Iterable

from absl.testing import absltest
from absl.testing import parameterized

import tink

from util import key_util
from util import testing_servers
from util import utilities


def all_template_names() -> Iterable[str]:
  for names in utilities.KEY_TEMPLATE_NAMES.values():
    for name in names:
      yield name


# These key templates are not defined in these languages.
UNDEFINED_TEMPLATES = [
    ('ECDSA_P384', 'go'),
    ('ECDSA_P384_SHA384_IEEE_P1363', 'cc'),
    ('ECDSA_P384_SHA384_IEEE_P1363', 'java'),
    ('ECDSA_P384_SHA384_IEEE_P1363', 'go'),
    ('AES128_GCM_HKDF_1MB', 'cc'),
    ('ECIES_P256_COMPRESSED_HKDF_HMAC_SHA256_AES128_GCM', 'go'),
    ('ECIES_P256_COMPRESSED_HKDF_HMAC_SHA256_AES128_CTR_HMAC_SHA256', 'go'),
    ('ECDSA_P256_IEEE_P1363', 'go'),
    ('ECDSA_P384_IEEE_P1363', 'go'),
    ('ECDSA_P521_IEEE_P1363', 'go'),
    ('AES128_EAX_RAW', 'cc'),
    ('AES256_EAX_RAW', 'cc'),
    ('AES128_GCM_SIV_RAW', 'cc'),
    ('AES256_GCM_SIV_RAW', 'cc'),
    ('AES128_GCM_SIV_RAW', 'go'),
    ('AES128_GCM_RAW', 'go'),
    ('AES128_CTR_HMAC_SHA256_RAW', 'cc'),
    ('AES256_CTR_HMAC_SHA256_RAW', 'cc'),
    ('AES128_CTR_HMAC_SHA256_RAW', 'go'),
    ('AES256_CTR_HMAC_SHA256_RAW', 'go'),
    ('CHACHA20_POLY1305_RAW', 'go'),
    ('XCHACHA20_POLY1305_RAW', 'cc'),
    ('XCHACHA20_POLY1305_RAW', 'go'),
]


def setUpModule():
  testing_servers.start('key_generation_consistency')


def tearDownModule():
  testing_servers.stop()


class KeyGenerationConsistencyTest(parameterized.TestCase):

  @parameterized.parameters(all_template_names())
  def test_key_template_is_consistent(self, template_name):
    langs = utilities.SUPPORTED_LANGUAGES_BY_TEMPLATE_NAME[
        template_name]
    templates = {}
    for lang in langs:
      if (template_name, lang) in UNDEFINED_TEMPLATES:
        with self.assertRaises(
            tink.TinkError,
            msg=('(%s, %s) is in UNDEFINED_TEMPLATES, but does not fail.' %
                 (template_name, lang))):
          testing_servers.key_template(lang, template_name)
        continue
      try:
        templates[lang] = testing_servers.key_template(lang, template_name)
      except tink.TinkError as e:
        self.fail('(%s,%s): %s' % (lang, template_name, e))
    if len(templates) <= 1:
      # nothing to check.
      return
    langs = list(templates.keys())
    template = templates[langs[0]]
    for lang in langs[1:]:
      key_util.assert_tink_proto_equal(
          self,
          templates[lang],
          template,
          msg=('templates in %s and %s are not equal:' % (langs[0], lang)))


if __name__ == '__main__':
  absltest.main()