text: // Copyright (c) 2013 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "chrome/browser/extensions/token_cache/token_cache_service.h"
  
  #include "base/logging.h"
  #include "chrome/browser/signin/signin_manager_factory.h"
  #include "components/signin/core/browser/signin_manager.h"
  
  using base::Time;
  using base::TimeDelta;
  
  namespace extensions {
  
  TokenCacheService::TokenCacheService(Profile* profile) : profile_(profile) {
    SigninManagerFactory::GetForProfile(profile)->AddObserver(this);
  }
  
  TokenCacheService::~TokenCacheService() {
  }
  
  void TokenCacheService::StoreToken(const std::string& token_name,
                                     const std::string& token_value,
                                     base::TimeDelta time_to_live) {
    TokenCacheData token_data;
  
    // Get the current time, and make sure that the token has not already expired.
    Time expiration_time;
    TimeDelta zero_delta;
  
    // Negative time deltas are meaningless to this function.
    DCHECK(time_to_live >= zero_delta);
  
    if (zero_delta < time_to_live) {
      expiration_time = Time::Now();
      expiration_time += time_to_live;
    }
  
    token_data.token = token_value;
    token_data.expiration_time = expiration_time;
  
    // Add the token to our cache, overwriting any existing token with this name.
    token_cache_[token_name] = token_data;
  }
  
  // Retrieve a token for the currently logged in user.  This returns an empty
  // string if the token was not found or timed out.
  std::string TokenCacheService::RetrieveToken(const std::string& token_name) {
    std::map<std::string, TokenCacheData>::iterator it =
        token_cache_.find(token_name);
  
    if (it != token_cache_.end()) {
      Time now = Time::Now();
      if (it->second.expiration_time.is_null() ||
          now < it->second.expiration_time) {
        return it->second.token;
      } else {
        // Remove this entry if it is expired.
        token_cache_.erase(it);
        return std::string();
      }
    }
  
    return std::string();
  }
  
  void TokenCacheService::Shutdown() {
    SigninManagerFactory::GetForProfile(const_cast<Profile*>(profile_))
        ->RemoveObserver(this);
  }
  
  void TokenCacheService::GoogleSignedOut(const std::string& username) {
    token_cache_.clear();
  }
  
  }  // namespace extensions
  