text: /***
  * ==++==
  *
  * Copyright (c) Microsoft Corporation. All rights reserved.
  * 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.
  *
  * ==--==
  * =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
  *
  * Oauth2Client.cpp : Defines the entry point for the console application
  *
  * =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
  ****/
  
  /*
  
  INSTRUCTIONS
  
  This sample performs authorization code grant flow on various OAuth 2.0
  services and then requests basic user information.
  
  This sample is for Windows Desktop, OS X and Linux.
  Execute with administrator privileges.
  
  Set the app key & secret strings below (i.e. s_dropbox_key, s_dropbox_secret, etc.)
  To get key & secret, register an app in the corresponding service.
  
  Set following entry in the hosts file:
  127.0.0.1    testhost.local
  
  */
  #include "stdafx.h"
  
  #if defined(_WIN32) && !defined(__cplusplus_winrt)
  // Extra includes for Windows desktop.
  #include <windows.h>
  #include <Shellapi.h>
  #endif
  
  #include "cpprest/http_listener.h"
  #include "cpprest/http_client.h"
  
  using namespace utility;
  using namespace web;
  using namespace web::http;
  using namespace web::http::client;
  using namespace web::http::oauth2::experimental;
  using namespace web::http::experimental::listener;
  
  //
  // Set key & secret pair to enable session for that service.
  //
  static const utility::string_t s_dropbox_key(U(""));
  static const utility::string_t s_dropbox_secret(U(""));
  
  static const utility::string_t s_linkedin_key(U(""));
  static const utility::string_t s_linkedin_secret(U(""));
  
  static const utility::string_t s_live_key(U(""));
  static const utility::string_t s_live_secret(U(""));
  
  //
  // Utility method to open browser on Windows, OS X and Linux systems.
  //
  static void open_browser(utility::string_t auth_uri)
  {
  #if defined(_WIN32) && !defined(__cplusplus_winrt)
      // NOTE: Windows desktop only.
      auto r = ShellExecuteA(NULL, "open", conversions::utf16_to_utf8(auth_uri).c_str(), NULL, NULL, SW_SHOWNORMAL);
  #elif defined(__APPLE__)
      // NOTE: OS X only.
      string_t browser_cmd(U("open \"") + auth_uri + U("\""));
      system(browser_cmd.c_str());
  #else
      // NOTE: Linux/X11 only.
      string_t browser_cmd(U("xdg-open \"") + auth_uri + U("\""));
      system(browser_cmd.c_str());
  #endif
  }
  
  //
  // A simple listener class to capture OAuth 2.0 HTTP redirect to localhost.
  // The listener captures redirected URI and obtains the token.
  // This type of listener can be implemented in the back-end to capture and store tokens.
  //
  class oauth2_code_listener
  {
  public:
      oauth2_code_listener(
          uri listen_uri,
          oauth2_config& config) :
              m_listener(new http_listener(listen_uri)),
              m_config(config)
      {
          m_listener->support([this](http::http_request request) -> void
          {
              if (request.request_uri().path() == U("/") && request.request_uri().query() != U(""))
              {
                  m_resplock.lock();
  
                  m_config.token_from_redirected_uri(request.request_uri()).then([this,request](pplx::task<void> token_task) -> void
                  {
                      try
                      {
                          token_task.wait();
                          m_tce.set(true);
                      }
                      catch (const oauth2_exception& e)
                      {
                          ucout << "Error: " << e.what() << std::endl;
                          m_tce.set(false);
                      }
                  });
  
                  request.reply(status_codes::OK, U("Ok."));
  
                  m_resplock.unlock();
              }
              else
              {
                  request.reply(status_codes::NotFound, U("Not found."));
              }
          });
  
          m_listener->open().wait();
      }
  
      ~oauth2_code_listener()
      {
          m_listener->close().wait();
      }
  
      pplx::task<bool> listen_for_code()
      {
          return pplx::create_task(m_tce);
      }
  
  private:
      std::unique_ptr<http_listener> m_listener;
      pplx::task_completion_event<bool> m_tce;
      oauth2_config& m_config;
      std::mutex m_resplock;
  };
  
  //
  // Base class for OAuth 2.0 sessions of this sample.
  //
  class oauth2_session_sample
  {
  public:
      oauth2_session_sample(utility::string_t name,
          utility::string_t client_key,
          utility::string_t client_secret,
          utility::string_t auth_endpoint,
          utility::string_t token_endpoint,
          utility::string_t redirect_uri) :
              m_oauth2_config(client_key,
                  client_secret,
                  auth_endpoint,
                  token_endpoint,
                  redirect_uri),
              m_name(name),
              m_listener(new oauth2_code_listener(redirect_uri, m_oauth2_config))
      {}
  
      void run()
      {
          if (is_enabled())
          {
              ucout << "Running " << m_name.c_str() << " session..." << std::endl;
  
              if (!m_oauth2_config.token().is_valid_access_token())
              {
                  if (authorization_code_flow().get())
                  {
                      m_http_config.set_oauth2(m_oauth2_config);
                  }
                  else
                  {
                      ucout << "Authorization failed for " << m_name.c_str() << "." << std::endl;
                  }
              }
  
              run_internal();
          }
          else
          {
              ucout << "Skipped " << m_name.c_str() << " session sample because app key or secret is empty. Please see instructions." << std::endl;
          }
      }
  
  protected:
      virtual void run_internal() = 0;
  
      pplx::task<bool> authorization_code_flow()
      {
          open_browser_auth();
          return m_listener->listen_for_code();
      }
  
      http_client_config m_http_config;
      oauth2_config m_oauth2_config;
  
  private:
      bool is_enabled() const
      {
          return !m_oauth2_config.client_key().empty() && !m_oauth2_config.client_secret().empty();
      }
  
      void open_browser_auth()
      {
          auto auth_uri(m_oauth2_config.build_authorization_uri(true));
          ucout << "Opening browser in URI:" << std::endl;
          ucout << auth_uri << std::endl;
          open_browser(auth_uri);
      }
  
      utility::string_t m_name;
      std::unique_ptr<oauth2_code_listener> m_listener;
  };
  
  //
  // Specialized class for Dropbox OAuth 2.0 session.
  //
  class dropbox_session_sample : public oauth2_session_sample
  {
  public:
      dropbox_session_sample() :
          oauth2_session_sample(U("Dropbox"),
              s_dropbox_key,
              s_dropbox_secret,
              U("https://www.dropbox.com/1/oauth2/authorize"),
              U("https://api.dropbox.com/1/oauth2/token"),
              U("http://localhost:8889/"))
      {
          // Dropbox uses "default" OAuth 2.0 settings.
      }
  
  protected:
      void run_internal() override
      {
          http_client api(U("https://api.dropbox.com/1/"), m_http_config);
          ucout << "Requesting account information:" << std::endl;
          ucout << "Information: " << api.request(methods::GET, U("account/info")).get().extract_json().get() << std::endl;
      }
  };
  
  //
  // Specialized class for LinkedIn OAuth 2.0 session.
  //
  class linkedin_session_sample : public oauth2_session_sample
  {
  public:
      linkedin_session_sample() :
          oauth2_session_sample(U("LinkedIn"),
              s_linkedin_key,
              s_linkedin_secret,
              U("https://www.linkedin.com/uas/oauth2/authorization"),
              U("https://www.linkedin.com/uas/oauth2/accessToken"),
              U("http://localhost:8888/"))
      {
          // LinkedIn doesn't use bearer auth.
          m_oauth2_config.set_bearer_auth(false);
          // Also doesn't use HTTP Basic for token endpoint authentication.
          m_oauth2_config.set_http_basic_auth(false);
          // Also doesn't use the common "access_token", but "oauth2_access_token".
          m_oauth2_config.set_access_token_key(U("oauth2_access_token"));
      }
  
  protected:
      void run_internal() override
      {
          http_client api(U("https://api.linkedin.com/v1/people/"), m_http_config);
          ucout << "Requesting account information:" << std::endl;
          ucout << "Information: " << api.request(methods::GET, U("~?format=json")).get().extract_json().get() << std::endl;
      }
  
  };
  
  //
  // Specialized class for Microsoft Live Connect OAuth 2.0 session.
  //
  class live_session_sample : public oauth2_session_sample
  {
  public:
      live_session_sample() :
          oauth2_session_sample(U("Live"),
              s_live_key,
              s_live_secret,
              U("https://login.live.com/oauth20_authorize.srf"),
              U("https://login.live.com/oauth20_token.srf"),
              U("http://testhost.local:8890/"))
      {
          // Scope "wl.basic" allows fetching user information.
          m_oauth2_config.set_scope(U("wl.basic"));
      }
  
  protected:
      void run_internal() override
      {
          http_client api(U("https://apis.live.net/v5.0/"), m_http_config);
          ucout << "Requesting account information:" << std::endl;
          ucout << api.request(methods::GET, U("me")).get().extract_json().get() << std::endl;
      }
  };
  
  
  #ifdef _WIN32
  int wmain(int argc, wchar_t *argv[])
  #else
  int main(int argc, char *argv[])
  #endif
  {
      ucout << "Running OAuth 2.0 client sample..." << std::endl;
  
      linkedin_session_sample linkedin;
      dropbox_session_sample  dropbox;
      live_session_sample     live;
  
      linkedin.run();
      dropbox.run();
      live.run();
  
      ucout << "Done." << std::endl;
      return 0;
  }
  