import 'dart:convert';
import 'dart:io';
import 'package:angel_auth/angel_auth.dart';
import 'package:angel_diagnostics/angel_diagnostics.dart';
import 'package:angel_framework/angel_framework.dart';
import 'package:angel_framework/common.dart';
import 'package:angel_auth_oauth2/angel_auth_oauth2.dart';
import 'package:oauth2/oauth2.dart' as oauth2;

const AngelAuthOAuth2Options OAUTH2_CONFIG = const AngelAuthOAuth2Options(
    callback: 'http://localhost:3000/auth/github/callback',
    key: '6caeaf5d4c04936ec34f',
    secret: '178360518cf9de4802e2346a4b6ebec525dc4427',
    authorizationEndpoint: 'http://github.com/login/oauth/authorize',
    tokenEndpoint: 'https://github.com/login/oauth/access_token');

main() async {
  var app = new Angel();
  app.lazyParseBodies = true;
  app.use('/users', new MapService());

  var auth = new AngelAuth(jwtKey: 'oauth2 example secret', allowCookie: false);

  auth.deserializer = app.service('users').read;
  auth.serializer = (User user) async => user.id;

  auth.strategies.add(
      new OAuth2Strategy('github', OAUTH2_CONFIG, (oauth2.Client client) async {
    var response = await client.get('https://api.github.com/user');
    var ghUser = JSON.decode(response.body);
    var id = ghUser['id'];

    Iterable<Map> matchingUsers = await app.service('users').index({
      'query': {'githubId': id}
    });

    if (matchingUsers.isNotEmpty) {
      // Return the corresponding user, if it exists
      return User.parse(matchingUsers.firstWhere((u) => u['githubId'] == id));
    } else {
      // Otherwise,create a user
      return await app
          .service('users')
          .create({'githubId': id}).then(User.parse);
    }
  }));

  app.get('/auth/github', auth.authenticate('github'));
  app.get(
      '/auth/github/callback',
      auth.authenticate('github',
          new AngelAuthOptions(callback: (req, res, jwt) async {
        // In real-life, you might include a pop-up callback script.
        //
        // Use `confirmPopupAuthentication`, which is bundled with
        // `package:angel_auth`.
        res.write('Your JWT: $jwt');
      })));

  await app.configure(auth);
  await app.configure(logRequests());

  var server = await app.startServer(InternetAddress.LOOPBACK_IP_V4, 3000);
  var url = 'http://${server.address.address}:${server.port}';
  print('Listening on $url');
  print('View user listing: $url/users');
  print('Sign in via Github: $url/auth/github');
}

class User extends Model {
  @override
  String id;
  int githubId;

  User({this.id, this.githubId});

  static User parse(Map map) =>
      new User(id: map['id'], githubId: map['github_id']);

  Map<String, dynamic> toJson() => {'id': id, 'github_id': githubId};
}