blob: 634da9a966586d9da773fdab28217e6163525bce [file] [log] [blame]
// Copyright (c) 2012 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 <stddef.h>
#include <list>
#include <map>
#include <memory>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/strings/string16.h"
#include "base/threading/thread.h"
#include "base/threading/thread_checker.h"
#include "device/geolocation/geolocation_export.h"
#include "device/geolocation/geoposition.h"
#include "device/geolocation/location_provider.h"
#include "device/geolocation/network_location_request.h"
#include "device/geolocation/wifi_data_provider_manager.h"
namespace device {
class AccessTokenStore;
class NetworkLocationProvider : public LocationProvider {
// Cache of recently resolved locations. Public for tests.
// The maximum size of the cache of positions.
static const size_t kMaximumSize;
// Caches the current position response for the current set of cell ID and
// WiFi data. In the case of the cache exceeding kMaximumSize this will
// evict old entries in FIFO orderer of being added.
// Returns true on success, false otherwise.
bool CachePosition(const WifiData& wifi_data, const Geoposition& position);
// Searches for a cached position response for the current set of data.
// Returns NULL if the position is not in the cache, or the cached
// position if available. Ownership remains with the cache.
const Geoposition* FindPosition(const WifiData& wifi_data);
// Makes the key for the map of cached positions, using a set of
// data. Returns true if a good key was generated, false otherwise.
static bool MakeKey(const WifiData& wifi_data, base::string16* key);
// The cache of positions. This is stored as a map keyed on a string that
// represents a set of data, and a list to provide
// least-recently-added eviction.
typedef std::map<base::string16, Geoposition> CacheMap;
CacheMap cache_;
typedef std::list<CacheMap::iterator> CacheAgeList;
CacheAgeList cache_age_list_; // Oldest first.
const scoped_refptr<AccessTokenStore>& access_token_store,
const scoped_refptr<net::URLRequestContextGetter>& context,
const GURL& url,
const base::string16& access_token);
~NetworkLocationProvider() override;
// LocationProvider implementation
void SetUpdateCallback(const LocationProviderUpdateCallback& cb) override;
bool StartProvider(bool high_accuracy) override;
void StopProvider() override;
const Geoposition& GetPosition() override;
void OnPermissionGranted() override;
// Tries to update |position_| request from cache or network.
void RequestPosition();
// Gets called when new wifi data is available, either via explicit request to
// or callback from |wifi_data_provider_manager_|.
void OnWifiDataUpdate();
bool IsStarted() const;
void OnLocationResponse(const Geoposition& position,
bool server_error,
const base::string16& access_token,
const WifiData& wifi_data);
const scoped_refptr<AccessTokenStore> access_token_store_;
// The wifi data provider, acquired via global factories. Valid between
// StartProvider() and StopProvider(), and checked via IsStarted().
WifiDataProviderManager* wifi_data_provider_manager_;
WifiDataProviderManager::WifiDataUpdateCallback wifi_data_update_callback_;
// The wifi data and a flag to indicate if the data set is complete.
WifiData wifi_data_;
bool is_wifi_data_complete_;
// The timestamp for the latest wifi data update.
base::Time wifi_timestamp_;
// Cached value loaded from the token store or set by a previous server
// response, and sent in each subsequent network request.
base::string16 access_token_;
// The current best position estimate.
Geoposition position_;
// Whether permission has been granted for the provider to operate.
bool is_permission_granted_;
bool is_new_data_available_;
// The network location request object, and the url it uses.
const std::unique_ptr<NetworkLocationRequest> request_;
// The cache of positions.
const std::unique_ptr<PositionCache> position_cache_;
base::ThreadChecker thread_checker_;
base::WeakPtrFactory<NetworkLocationProvider> weak_factory_;
// Factory functions for the various types of location provider to abstract
// over the platform-dependent implementations.
DEVICE_GEOLOCATION_EXPORT LocationProvider* NewNetworkLocationProvider(
const scoped_refptr<AccessTokenStore>& access_token_store,
const scoped_refptr<net::URLRequestContextGetter>& context,
const GURL& url,
const base::string16& access_token);
} // namespace device