import base64
import unittest

from datetime import datetime, timedelta
from tempfile import NamedTemporaryFile

import jwt
import requests

from Crypto.PublicKey import RSA
from flask import Flask, jsonify, request, make_response
from flask_testing import LiveServerTestCase

from app import app
from data.users import ExternalJWTAuthN
from initdb import setup_database_for_testing, finished_database_for_testing


_PORT_NUMBER = 5001


class JWTAuthTestCase(LiveServerTestCase):
  maxDiff = None

  @classmethod
  def setUpClass(cls):
    public_key = NamedTemporaryFile(delete=True)

    key = RSA.generate(1024)
    private_key_data = key.exportKey('PEM')

    pubkey = key.publickey()
    public_key.write(pubkey.exportKey('OpenSSH'))
    public_key.seek(0)

    JWTAuthTestCase.public_key = public_key
    JWTAuthTestCase.private_key_data = private_key_data

  def create_app(self):
    global _PORT_NUMBER
    _PORT_NUMBER = _PORT_NUMBER + 1

    users = [
      {'name': 'cooluser', 'email': 'user@domain.com', 'password': 'password'},
      {'name': 'some.neat.user', 'email': 'neat@domain.com', 'password': 'foobar'}
    ]

    jwt_app = Flask('testjwt')
    private_key = JWTAuthTestCase.private_key_data
    jwt_app.config['LIVESERVER_PORT'] = _PORT_NUMBER

    def _get_basic_auth():
      data = base64.b64decode(request.headers['Authorization'][len('Basic '):])
      return data.split(':', 1)

    @jwt_app.route('/user/verify', methods=['GET'])
    def verify_user():
      username, password = _get_basic_auth()

      if username == 'disabled':
        return make_response('User is currently disabled', 401)

      for user in users:
        if user['name'] == username or user['email'] == username:
          if password != user['password']:
            return make_response('', 404)

          token_data = {
            'iss': 'authy',
            'aud': 'quay.io/jwtauthn',
            'nbf': datetime.utcnow(),
            'iat': datetime.utcnow(),
            'exp': datetime.utcnow() + timedelta(seconds=60),
            'sub': user['name'],
            'email': user['email']
          }

          encoded = jwt.encode(token_data, private_key, 'RS256')
          return jsonify({
            'token': encoded
          })

      return make_response('', 404)

    jwt_app.config['TESTING'] = True
    return jwt_app


  def setUp(self):
    setup_database_for_testing(self)
    self.app = app.test_client()
    self.ctx = app.test_request_context()
    self.ctx.__enter__()

    self.session = requests.Session()

    self.jwt_auth = ExternalJWTAuthN(self.get_server_url() + '/user/verify', 'authy', '',
                                     app.config['HTTPCLIENT'], 300, JWTAuthTestCase.public_key.name)

  def tearDown(self):
    finished_database_for_testing(self)
    self.ctx.__exit__(True, None, None)

  def test_verify_and_link_user(self):
    result, error_message = self.jwt_auth.verify_and_link_user('invaliduser', 'foobar')
    self.assertEquals('Invalid username or password', error_message)
    self.assertIsNone(result)

    result, _ = self.jwt_auth.verify_and_link_user('cooluser', 'invalidpassword')
    self.assertIsNone(result)

    result, _ = self.jwt_auth.verify_and_link_user('cooluser', 'password')
    self.assertIsNotNone(result)
    self.assertEquals('cooluser', result.username)

    result, _ = self.jwt_auth.verify_and_link_user('some.neat.user', 'foobar')
    self.assertIsNotNone(result)
    self.assertEquals('some_neat_user', result.username)

  def test_confirm_existing_user(self):
    # Create the users in the DB.
    result, _ = self.jwt_auth.verify_and_link_user('cooluser', 'password')
    self.assertIsNotNone(result)

    result, _ = self.jwt_auth.verify_and_link_user('some.neat.user', 'foobar')
    self.assertIsNotNone(result)

    # Confirm a user with the same internal and external username.
    result, _ = self.jwt_auth.confirm_existing_user('cooluser', 'invalidpassword')
    self.assertIsNone(result)

    result, _ = self.jwt_auth.confirm_existing_user('cooluser', 'password')
    self.assertIsNotNone(result)
    self.assertEquals('cooluser', result.username)

    # Fail to confirm the *external* username, which should return nothing.
    result, _ = self.jwt_auth.confirm_existing_user('some.neat.user', 'password')
    self.assertIsNone(result)

    # Now confirm the internal username.
    result, _ = self.jwt_auth.confirm_existing_user('some_neat_user', 'foobar')
    self.assertIsNotNone(result)
    self.assertEquals('some_neat_user', result.username)

  def test_disabled_user_custom_erorr(self):
    result, error_message = self.jwt_auth.verify_and_link_user('disabled', 'password')
    self.assertIsNone(result)
    self.assertEquals('User is currently disabled', error_message)


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