import express = require("express");
import OAuth2Server = require("oauth2-server");

const oauth2Model: OAuth2Server.AuthorizationCodeModel = {
  generateAuthorizationCode: async (client, user, scope) => {
    return JSON.stringify({
      client,
      user,
      scope,
    });
  },
  getClient: async (
    clientId: string,
    clientSecret: string,
  ): Promise<OAuth2Server.Client | OAuth2Server.Falsey> => {
    return undefined;
  },
  saveToken: async (
    token: OAuth2Server.Token,
    client: OAuth2Server.Client,
    user: OAuth2Server.User,
  ): Promise<OAuth2Server.Token> => {
    return token;
  },
  getAccessToken: async (accessToken: string): Promise<OAuth2Server.Token> => {
    return {
      accessToken,
      client: { id: 'testClient', grants: ['access_token'] },
      user: { id: 'testUser' },
    };
  },
  verifyScope: async (
    token: OAuth2Server.Token,
    scope: string,
  ): Promise<boolean> => {
    return true;
  },
  getAuthorizationCode: async (
    authorizationCode: string,
  ): Promise<OAuth2Server.AuthorizationCode> => {
    return {
      authorizationCode,
      expiresAt: new Date(),
      redirectUri: 'www.test.com',
      client: { id: 'testClient', grants: ['access_token'] },
      user: { id: 'testUser' },
    };
  },
  saveAuthorizationCode: async (
    code,
    client: OAuth2Server.Client,
    user: OAuth2Server.User,
  ): Promise<OAuth2Server.AuthorizationCode> => {
    return { ...code, user, client };
  },
  revokeAuthorizationCode: async (
    code: OAuth2Server.AuthorizationCode,
  ): Promise<boolean> => {
    return true;
  },
};

const oauth2Server = new OAuth2Server({
    model: oauth2Model
});

// Authenticate user with supplied bearer token
const authenticate = (authenticateOptions?: {}) => {
    const options: undefined | {} = authenticateOptions || {};
    return async (req: express.Request & {user: OAuth2Server.Token}, res: express.Response, next: express.NextFunction) => {
        const request = new OAuth2Server.Request(req);
        const response = new OAuth2Server.Response(res);

        try {
            // Test async method of accessing oauth2Server
            const token = await oauth2Server.authenticate(request, response, options);
            req.user = token;
            next();
        } catch (err) {
            res.status(err.code || 500).json(err);
        }
    };
};

const app = express();
app.all('/oauth2/token', (req: express.Request, res: express.Response, next: express.NextFunction) => {
    const request = new OAuth2Server.Request(req);
    const response = new OAuth2Server.Response(res);

    oauth2Server.token(request, response)
        .then((token: OAuth2Server.Token) => {
            res.json(token);
        }).catch((err: any) => {
            res.status(err.code || 500).json(err);
        });
});

app.post('/oauth2/authorize', (req, res) => {
    const request = new OAuth2Server.Request(req);
    const response = new OAuth2Server.Response(res);

    oauth2Server.authorize(request, response)
        .then((success: OAuth2Server.AuthorizationCode) => {
            res.json(success);
        }).catch((err: any) => {
            res.status(err.code || 500).json(err);
        });
});

app.get('/secure', authenticate(), (req: express.Request & {user: OAuth2Server.Token}, res: express.Response, next: express.NextFunction) => {
    res.json({message: 'Secure data'});
});

app.get('/profile', authenticate({scope: 'profile'}), (req: express.Request & {user: OAuth2Server.Token}, res: express.Response, next: express.NextFunction) => {
    res.json({
        profile: req.user
    });
});

app.listen(3000);