# SPDX-FileCopyrightText: 2020 The Magma Authors.
# SPDX-FileCopyrightText: 2022 Open Networking Foundation <support@opennetworking.org>
#
# SPDX-License-Identifier: BSD-3-Clause

import base64
import datetime
import os
from tempfile import TemporaryDirectory
from unittest import TestCase

import magma.common.cert_utils as cu
from cryptography import x509
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import ec


class CertUtilsTest(TestCase):
    def test_key(self):
        with TemporaryDirectory(prefix='/tmp/test_cert_utils') as temp_dir:
            key = ec.generate_private_key(ec.SECP384R1(), default_backend())
            cu.write_key(key, os.path.join(temp_dir, 'test.key'))
            key_load = cu.load_key(os.path.join(temp_dir, 'test.key'))

        key_bytes = key.private_bytes(
            serialization.Encoding.PEM,
            serialization.PrivateFormat.TraditionalOpenSSL,
            serialization.NoEncryption(),
        )
        key_load_bytes = key_load.private_bytes(
            serialization.Encoding.PEM,
            serialization.PrivateFormat.TraditionalOpenSSL,
            serialization.NoEncryption(),
        )
        self.assertEqual(key_bytes, key_load_bytes)

    def load_public_key_to_base64der(self):
        with TemporaryDirectory(prefix='/tmp/test_cert_utils') as temp_dir:
            key = ec.generate_private_key(ec.SECP384R1(), default_backend())
            cu.write_key(key, os.path.join(temp_dir, 'test.key'))
            base64der = cu.load_public_key_to_base64der(
                os.path.join(temp_dir, 'test.key'),
            )
            der = base64.b64decode(base64der)
            pub_key = serialization.load_der_public_key(der, default_backend())
            self.assertEqual(pub_key, key.public_key())

    def test_csr(self):
        key = ec.generate_private_key(ec.SECP384R1(), default_backend())
        csr = cu.create_csr(
            key, 'i am dummy test',
            'US', 'CA', 'MPK', 'FB', 'magma', 'magma@fb.com',
        )
        self.assertTrue(csr.is_signature_valid)
        public_key_bytes = key.public_key().public_bytes(
            serialization.Encoding.OpenSSH,
            serialization.PublicFormat.OpenSSH,
        )
        csr_public_key_bytes = csr.public_key().public_bytes(
            serialization.Encoding.OpenSSH,
            serialization.PublicFormat.OpenSSH,
        )
        self.assertEqual(public_key_bytes, csr_public_key_bytes)

    def test_cert(self):
        with TemporaryDirectory(prefix='/tmp/test_cert_utils') as temp_dir:
            cert = _create_dummy_cert()
            cert_file = os.path.join(temp_dir, 'test.cert')
            cu.write_cert(
                cert.public_bytes(
                serialization.Encoding.DER,
                ), cert_file,
            )
            cert_load = cu.load_cert(cert_file)
        self.assertEqual(cert, cert_load)


def _create_dummy_cert():
    key = ec.generate_private_key(ec.SECP384R1(), default_backend())
    subject = issuer = x509.Name([
        x509.NameAttribute(x509.oid.NameOID.COUNTRY_NAME, u"US"),
        x509.NameAttribute(x509.oid.NameOID.STATE_OR_PROVINCE_NAME, u"CA"),
        x509.NameAttribute(x509.oid.NameOID.LOCALITY_NAME, u"San Francisco"),
        x509.NameAttribute(x509.oid.NameOID.ORGANIZATION_NAME, u"My Company"),
        x509.NameAttribute(x509.oid.NameOID.COMMON_NAME, u"mysite.com"),
    ])
    cert = x509.CertificateBuilder().subject_name(
        subject,
    ).issuer_name(
        issuer,
    ).public_key(
        key.public_key(),
    ).serial_number(
        x509.random_serial_number(),
    ).not_valid_before(
        datetime.datetime.utcnow(),
    ).not_valid_after(
        datetime.datetime.utcnow() + datetime.timedelta(days=10),
    ).sign(key, hashes.SHA256(), default_backend())
    return cert