#ifndef REMOTING_HOST_OAUTH_TOKEN_GETTER_H_
#define REMOTING_HOST_OAUTH_TOKEN_GETTER_H_
#include <queue>
#include "base/basictypes.h"
#include "base/callback.h"
#include "base/threading/non_thread_safe.h"
#include "google_apis/gaia/gaia_oauth_client.h"
namespace net {
class URLRequestContextGetter;
}  
namespace remoting {
class OAuthTokenGetter :
      public base::NonThreadSafe,
      public gaia::GaiaOAuthClient::Delegate {
 public:
  
  enum Status {
    
    SUCCESS,
    
    NETWORK_ERROR,
    
    AUTH_ERROR,
  };
  typedef base::Callback<void(Status status,
                              const std::string& user_email,
                              const std::string& access_token)> TokenCallback;
  
  
  struct OAuthCredentials {
    OAuthCredentials(const std::string& login,
                     const std::string& refresh_token,
                     bool is_service_account);
    
    std::string login;
    
    std::string refresh_token;
    
    bool is_service_account;
  };
  OAuthTokenGetter(
      scoped_ptr<OAuthCredentials> oauth_credentials,
      scoped_refptr<net::URLRequestContextGetter> url_request_context_getter);
  virtual ~OAuthTokenGetter();
  
  void CallWithToken(const OAuthTokenGetter::TokenCallback& on_access_token);
  
  virtual void OnGetTokensResponse(const std::string& user_email,
                                   const std::string& access_token,
                                   int expires_seconds) OVERRIDE;
  virtual void OnRefreshTokenResponse(const std::string& access_token,
                                      int expires_in_seconds) OVERRIDE;
  virtual void OnGetUserEmailResponse(const std::string& user_email) OVERRIDE;
  virtual void OnOAuthError() OVERRIDE;
  virtual void OnNetworkError(int response_code) OVERRIDE;
 private:
  void NotifyCallbacks(Status status,
                       const std::string& user_email,
                       const std::string& access_token);
  void RefreshOAuthToken();
  scoped_ptr<OAuthCredentials> oauth_credentials_;
  scoped_ptr<gaia::GaiaOAuthClient> gaia_oauth_client_;
  scoped_refptr<net::URLRequestContextGetter> url_request_context_getter_;
  bool refreshing_oauth_token_;
  std::string oauth_access_token_;
  base::Time auth_token_expiry_time_;
  std::queue<OAuthTokenGetter::TokenCallback> pending_callbacks_;
  DISALLOW_COPY_AND_ASSIGN(OAuthTokenGetter);
};
}  
#endif