blob: eae4ee06b5ea1a4289fcdb8dc87adb5088329600 [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 <stdint.h>
#include <memory>
#include <string>
#include <vector>
#include "base/callback_forward.h"
#include "base/cancelable_callback.h"
#include "base/macros.h"
#include "base/strings/string16.h"
#include "base/time/time.h"
#include "services/device/geolocation/geolocation_provider_impl.h"
#include "services/device/geolocation/network_location_provider.h"
#include "services/device/geolocation/position_cache.h"
#include "services/device/public/cpp/geolocation/location_provider.h"
#include "services/device/public/mojom/geoposition.mojom.h"
#include "url/gurl.h"
namespace network {
class SharedURLLoaderFactory;
namespace device {
// This class is responsible for handling updates from multiple underlying
// providers and resolving them to a single 'best' location fix at any given
// moment.
class LocationArbitrator : public LocationProvider {
// The TimeDelta newer a location provider has to be that it's worth
// switching to this location provider on the basis of it being fresher
// (regardles of relative accuracy). Public for tests.
static const base::TimeDelta kFixStaleTimeoutTimeDelta;
// If the |custom_location_provider_getter| callback returns nullptr, then
// LocationArbitrator uses the default system location provider.
const CustomLocationProviderCallback& custom_location_provider_getter,
const scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory,
const std::string& api_key,
std::unique_ptr<PositionCache> position_cache);
~LocationArbitrator() override;
static GURL DefaultNetworkProviderURL();
bool HasPermissionBeenGrantedForTest() const;
// LocationProvider implementation.
void SetUpdateCallback(
const LocationProviderUpdateCallback& callback) override;
void StartProvider(bool enable_high_accuracy) override;
void StopProvider() override;
const mojom::Geoposition& GetPosition() override;
void OnPermissionGranted() override;
// These functions are useful for injection of dependencies in derived
// testing classes.
virtual std::unique_ptr<LocationProvider> NewNetworkLocationProvider(
scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory,
const std::string& api_key);
virtual std::unique_ptr<LocationProvider> NewSystemLocationProvider();
virtual base::Time GetTimeNow() const;
friend class TestingLocationArbitrator;
// Provider will either be added to |providers_| or
// deleted on error (e.g. it fails to start).
void RegisterProvider(std::unique_ptr<LocationProvider> provider);
void RegisterSystemProvider();
void RegisterNetworkProvider();
// Tells all registered providers to start.
// If |providers_| is empty, immediately provides
// Geoposition::ERROR_CODE_POSITION_UNAVAILABLE to the client via
// |arbitrator_update_callback_|.
void DoStartProviders();
// Gets called when a provider has a new position.
void OnLocationUpdate(const LocationProvider* provider,
const mojom::Geoposition& new_position);
// Returns true if |new_position| is an improvement over |old_position|.
// Set |from_same_provider| to true if both the positions came from the same
// provider.
bool IsNewPositionBetter(const mojom::Geoposition& old_position,
const mojom::Geoposition& new_position,
bool from_same_provider) const;
const CustomLocationProviderCallback custom_location_provider_getter_;
const scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory_;
const std::string api_key_;
LocationProvider::LocationProviderUpdateCallback arbitrator_update_callback_;
std::vector<std::unique_ptr<LocationProvider>> providers_;
bool enable_high_accuracy_;
// The provider which supplied the current |position_|
const LocationProvider* position_provider_;
bool is_permission_granted_;
// The current best estimate of our position.
mojom::Geoposition position_;
std::unique_ptr<PositionCache> position_cache_;
// Tracks whether providers should be running.
bool is_running_;
// Factory functions for the various types of location provider to abstract
// over the platform-dependent implementations.
std::unique_ptr<LocationProvider> NewSystemLocationProvider();
} // namespace device