blob: daf0c8b4417e5175ef16e4d430f74334f4e5e6eb [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 <list>
#include <map>
#include "base/basictypes.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/strings/string16.h"
#include "base/threading/non_thread_safe.h"
#include "base/threading/thread.h"
#include "content/browser/geolocation/location_provider_base.h"
#include "content/browser/geolocation/network_location_request.h"
#include "content/browser/geolocation/wifi_data_provider.h"
#include "content/common/content_export.h"
#include "content/public/common/geoposition.h"
namespace content {
class AccessTokenStore;
class NetworkLocationProvider
: public base::NonThreadSafe,
public LocationProviderBase {
// Cache of recently resolved locations. Public for tests.
class CONTENT_EXPORT PositionCache {
// 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.
NetworkLocationProvider(AccessTokenStore* access_token_store,
net::URLRequestContextGetter* context,
const GURL& url,
const base::string16& access_token);
virtual ~NetworkLocationProvider();
// LocationProvider implementation
virtual bool StartProvider(bool high_accuracy) OVERRIDE;
virtual void StopProvider() OVERRIDE;
virtual void GetPosition(Geoposition *position) OVERRIDE;
virtual void RequestRefresh() OVERRIDE;
virtual void OnPermissionGranted() OVERRIDE;
// Satisfies a position request from cache or network.
void RequestPosition();
// Gets called when new wifi data is available.
void OnWifiDataUpdate(WifiDataProvider* provider);
// Internal helper used by OnWifiDataUpdate.
void OnWifiDataUpdated();
bool IsStarted() const;
void OnLocationResponse(const Geoposition& position,
bool server_error,
const base::string16& access_token,
const WifiData& wifi_data);
scoped_refptr<AccessTokenStore> access_token_store_;
// The wifi data provider, acquired via global factories.
WifiDataProvider* wifi_data_provider_;
WifiDataProvider::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_data_updated_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.
scoped_ptr<NetworkLocationRequest> request_;
// The cache of positions.
scoped_ptr<PositionCache> position_cache_;
base::WeakPtrFactory<NetworkLocationProvider> weak_factory_;
// Factory functions for the various types of location provider to abstract
// over the platform-dependent implementations.
CONTENT_EXPORT LocationProviderBase* NewNetworkLocationProvider(
AccessTokenStore* access_token_store,
net::URLRequestContextGetter* context,
const GURL& url,
const base::string16& access_token);
} // namespace content