Revert of Reland: Geolocation: move from content/browser to device/

content/browser/geolocation/network_location_provider.cc

Index: content/browser/geolocation/network_location_provider.cc
diff --git a/content/browser/geolocation/network_location_provider.cc b/content/browser/geolocation/network_location_provider.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0c6e6db4c74c94a275935c450ccc8782facf7228
--- /dev/null
+++ b/content/browser/geolocation/network_location_provider.cc
@@ -0,0 +1,273 @@
+// 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 "content/browser/geolocation/network_location_provider.h"
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "base/time/time.h"
+#include "content/public/browser/access_token_store.h"
+
+namespace content {
+namespace {
+// The maximum period of time we'll wait for a complete set of wifi data
+// before sending the request.
+const int kDataCompleteWaitSeconds = 2;
+}  // namespace
+
+// static
+const size_t NetworkLocationProvider::PositionCache::kMaximumSize = 10;
+
+NetworkLocationProvider::PositionCache::PositionCache() {}
+
+NetworkLocationProvider::PositionCache::~PositionCache() {}
+
+bool NetworkLocationProvider::PositionCache::CachePosition(
+    const WifiData& wifi_data,
+    const Geoposition& position) {
+  // Check that we can generate a valid key for the wifi data.
+  base::string16 key;
+  if (!MakeKey(wifi_data, &key)) {
+    return false;
+  }
+  // If the cache is full, remove the oldest entry.
+  if (cache_.size() == kMaximumSize) {
+    DCHECK(cache_age_list_.size() == kMaximumSize);
+    CacheAgeList::iterator oldest_entry = cache_age_list_.begin();
+    DCHECK(oldest_entry != cache_age_list_.end());
+    cache_.erase(*oldest_entry);
+    cache_age_list_.erase(oldest_entry);
+  }
+  DCHECK_LT(cache_.size(), kMaximumSize);
+  // Insert the position into the cache.
+  std::pair<CacheMap::iterator, bool> result =
+      cache_.insert(std::make_pair(key, position));
+  if (!result.second) {
+    NOTREACHED();  // We never try to add the same key twice.
+    CHECK_EQ(cache_.size(), cache_age_list_.size());
+    return false;
+  }
+  cache_age_list_.push_back(result.first);
+  DCHECK_EQ(cache_.size(), cache_age_list_.size());
+  return true;
+}
+
+// Searches for a cached position response for the current WiFi data. Returns
+// the cached position if available, nullptr otherwise.
+const Geoposition* NetworkLocationProvider::PositionCache::FindPosition(
+    const WifiData& wifi_data) {
+  base::string16 key;
+  if (!MakeKey(wifi_data, &key)) {
+    return nullptr;
+  }
+  CacheMap::const_iterator iter = cache_.find(key);
+  return iter == cache_.end() ? nullptr : &iter->second;
+}
+
+// Makes the key for the map of cached positions, using the available data.
+// Returns true if a good key was generated, false otherwise.
+//
+// static
+bool NetworkLocationProvider::PositionCache::MakeKey(
+    const WifiData& wifi_data,
+    base::string16* key) {
+  // Currently we use only WiFi data and base the key only on the MAC addresses.
+  DCHECK(key);
+  key->clear();
+  const size_t kCharsPerMacAddress = 6 * 3 + 1;  // e.g. "11:22:33:44:55:66|"
+  key->reserve(wifi_data.access_point_data.size() * kCharsPerMacAddress);
+  const base::string16 separator(base::ASCIIToUTF16("|"));
+  for (const auto& access_point_data : wifi_data.access_point_data) {
+    *key += separator;
+    *key += access_point_data.mac_address;
+    *key += separator;
+  }
+  // If the key is the empty string, return false, as we don't want to cache a
+  // position for such data.
+  return !key->empty();
+}
+
+// NetworkLocationProvider factory function
+LocationProviderBase* NewNetworkLocationProvider(
+    const scoped_refptr<AccessTokenStore>& access_token_store,
+    const scoped_refptr<net::URLRequestContextGetter>& context,
+    const GURL& url,
+    const base::string16& access_token) {
+  return new NetworkLocationProvider(
+      access_token_store, context, url, access_token);
+}
+
+// NetworkLocationProvider
+NetworkLocationProvider::NetworkLocationProvider(
+    const scoped_refptr<AccessTokenStore>& access_token_store,
+    const scoped_refptr<net::URLRequestContextGetter>& url_context_getter,
+    const GURL& url,
+    const base::string16& access_token)
+    : access_token_store_(access_token_store),
+      wifi_data_provider_manager_(nullptr),
+      wifi_data_update_callback_(
+          base::Bind(&NetworkLocationProvider::OnWifiDataUpdate,
+                     base::Unretained(this))),
+      is_wifi_data_complete_(false),
+      access_token_(access_token),
+      is_permission_granted_(false),
+      is_new_data_available_(false),
+      position_cache_(new PositionCache),
+      weak_factory_(this) {
+  request_.reset(new NetworkLocationRequest(
+      url_context_getter,
+      url,
+      base::Bind(&NetworkLocationProvider::OnLocationResponse,
+                 base::Unretained(this))));
+}
+
+NetworkLocationProvider::~NetworkLocationProvider() {
+  StopProvider();
+}
+
+// LocationProvider implementation
+void NetworkLocationProvider::GetPosition(Geoposition* position) {
+  DCHECK(position);
+  *position = position_;
+}
+
+void NetworkLocationProvider::RequestRefresh() {
+  // TODO(joth): When called via the public (base class) interface, this should
+  // poke each data provider to get them to expedite their next scan.
+  // Whilst in the delayed start, only send request if all data is ready.
+  // TODO(mcasas): consider not using HasWeakPtrs() https://crbug.com/629158.
+  if (!weak_factory_.HasWeakPtrs() || is_wifi_data_complete_) {
+    RequestPosition();
+  }
+}
+
+void NetworkLocationProvider::OnPermissionGranted() {
+  const bool was_permission_granted = is_permission_granted_;
+  is_permission_granted_ = true;
+  if (!was_permission_granted && IsStarted()) {
+    RequestRefresh();
+  }
+}
+
+void NetworkLocationProvider::OnWifiDataUpdate() {
+  DCHECK(wifi_data_provider_manager_);
+  is_wifi_data_complete_ = wifi_data_provider_manager_->GetData(&wifi_data_);
+  OnWifiDataUpdated();
+}
+
+void NetworkLocationProvider::OnLocationResponse(
+    const Geoposition& position,
+    bool server_error,
+    const base::string16& access_token,
+    const WifiData& wifi_data) {
+  DCHECK(CalledOnValidThread());
+  // Record the position and update our cache.
+  position_ = position;
+  if (position.Validate()) {
+    position_cache_->CachePosition(wifi_data, position);
+  }
+
+  // Record access_token if it's set.
+  if (!access_token.empty() && access_token_ != access_token) {
+    access_token_ = access_token;
+    access_token_store_->SaveAccessToken(request_->url(), access_token);
+  }
+
+  // Let listeners know that we now have a position available.
+  NotifyCallback(position_);
+}
+
+bool NetworkLocationProvider::StartProvider(bool high_accuracy) {
+  DCHECK(CalledOnValidThread());
+  if (IsStarted())
+    return true;
+  DCHECK(!wifi_data_provider_manager_);
+  if (!request_->url().is_valid()) {
+    LOG(WARNING) << "StartProvider() : Failed, Bad URL: "
+                 << request_->url().possibly_invalid_spec();
+    return false;
+  }
+
+  // Registers a callback with the data provider. The first call to Register
+  // will create a singleton data provider and it will be deleted when the last
+  // callback is removed with Unregister.
+  wifi_data_provider_manager_ =
+      WifiDataProviderManager::Register(&wifi_data_update_callback_);
+
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, base::Bind(&NetworkLocationProvider::RequestPosition,
+                            weak_factory_.GetWeakPtr()),
+      base::TimeDelta::FromSeconds(kDataCompleteWaitSeconds));
+  // Get the wifi data.
+  is_wifi_data_complete_ = wifi_data_provider_manager_->GetData(&wifi_data_);
+  if (is_wifi_data_complete_)
+    OnWifiDataUpdated();
+  return true;
+}
+
+void NetworkLocationProvider::OnWifiDataUpdated() {
+  DCHECK(CalledOnValidThread());
+  wifi_timestamp_ = base::Time::Now();
+
+  is_new_data_available_ = is_wifi_data_complete_;
+  RequestRefresh();
+}
+
+void NetworkLocationProvider::StopProvider() {
+  DCHECK(CalledOnValidThread());
+  if (IsStarted()) {
+    wifi_data_provider_manager_->Unregister(&wifi_data_update_callback_);
+  }
+  wifi_data_provider_manager_ = nullptr;
+  weak_factory_.InvalidateWeakPtrs();
+}
+
+// Other methods
+void NetworkLocationProvider::RequestPosition() {
+  DCHECK(CalledOnValidThread());
+  if (!is_new_data_available_)
+    return;
+
+  const Geoposition* cached_position =
+      position_cache_->FindPosition(wifi_data_);
+  DCHECK(!wifi_timestamp_.is_null())
+      << "Timestamp must be set before looking up position";
+  if (cached_position) {
+    DCHECK(cached_position->Validate());
+    // Record the position and update its timestamp.
+    position_ = *cached_position;
+    // The timestamp of a position fix is determined by the timestamp
+    // of the source data update. (The value of position_.timestamp from
+    // the cache could be from weeks ago!)
+    position_.timestamp = wifi_timestamp_;
+    is_new_data_available_ = false;
+    // Let listeners know that we now have a position available.
+    NotifyCallback(position_);
+    return;
+  }
+  // Don't send network requests until authorized. http://crbug.com/39171
+  if (!is_permission_granted_)
+    return;
+
+  weak_factory_.InvalidateWeakPtrs();
+  is_new_data_available_ = false;
+
+  // TODO(joth): Rather than cancel pending requests, we should create a new
+  // NetworkLocationRequest for each and hold a set of pending requests.
+  if (request_->is_request_pending()) {
+    DVLOG(1) << "NetworkLocationProvider - pre-empting pending network request "
+                "with new data. Wifi APs: "
+             << wifi_data_.access_point_data.size();
+  }
+  request_->MakeRequest(access_token_, wifi_data_, wifi_timestamp_);
+}
+
+bool NetworkLocationProvider::IsStarted() const {
+  return wifi_data_provider_manager_ != nullptr;
+}
+
+}  // namespace content