Implementing a BLE connection finder.

components/proximity_auth/ble/bluetooth_low_energy_connection_finder.h

+// Copyright 2015 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.
+
+#ifndef COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_LOW_ENERGY_CONNECTION_FINDER_H
+#define COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_LOW_ENERGY_CONNECTION_FINDER_H
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "components/proximity_auth/connection_finder.h"
+#include "device/bluetooth/bluetooth_adapter.h"
+#include "device/bluetooth/bluetooth_device.h"
+#include "device/bluetooth/bluetooth_discovery_session.h"
+#include "device/bluetooth/bluetooth_gatt_connection.h"
+
+namespace proximity_auth {
+
+// This ConnectionFinder implementation is specialized in finding a Bluetooth
+// Low Energy remote device.
+class BluetoothLowEnergyConnectionFinder
+    : public ConnectionFinder,
+      public device::BluetoothAdapter::Observer {
+ public:
+  BluetoothLowEnergyConnectionFinder(const std::string& remote_service_uuid);
+  ~BluetoothLowEnergyConnectionFinder() override;
+
+  // Finds a connection the remote device, only the first one is functional.
+  void Find(const device::BluetoothDevice::GattConnectionCallback&
+                connection_callback);
+  void Find(const ConnectionCallback& connection_callback) override;
+
+ protected:
+  // device::BluetoothAdapter::Observer:
+  void DeviceAdded(device::BluetoothAdapter* adapter,
+                   device::BluetoothDevice* device) override;
+
+ private:
+  // Callback to be called when the Bluetooth adapter is initialized.
+  void OnAdapterInitialized(scoped_refptr<device::BluetoothAdapter> adapter);
+
+  // Checks if |remote_device| contains |remote_service_uuid| and creates a
+  // connection in that case.
+  void HandleDeviceAdded(device::BluetoothDevice* remote_device);
+
+  // Callback called when a new discovery session is started.
+  void OnDiscoverySessionStarted(
+      scoped_ptr<device::BluetoothDiscoverySession> discovery_session);
+
+  // Callback called when there is an error starting a new discovery session.
+  void OnStartDiscoverySessionError();
+
+  // Starts a discovery session for |adapter_|.
+  void StartDiscoverySession();
+
+  // Callback called when |discovery_session_| is stopped.
+  void OnDiscoverySessionStopped();
+
+  // Callback called when there is an error stopping |discovery_session_|.
+  void OnStopDiscoverySessionError();
+
+  // Stops the discovery session given by |discovery_session_|.
+  void StopDiscoverySession();
+
+  // Checks if a service with |service_uuid| is offered by |remote_device|.
+  bool HasService(device::BluetoothDevice* remote_device);
+
+  // Callback called when there is an error creating the connection.
+  void OnCreateConnectionError(
+      device::BluetoothDevice::ConnectErrorCode error_code);
+
+  // Callback called when the connection is created.
+  void OnConnectionCreated(
+      scoped_ptr<device::BluetoothGattConnection> connection);
+
+  // Creates a GATT connection with |remote_device|, |connection_callback_| will
+  // be called once the connection is established.
+  void CreateConnection(device::BluetoothDevice* remote_device);
+
+  // The uuid of the service it looks for to establish a GattConnection.
+  device::BluetoothUUID remote_service_uuid_;
+
+  // The Bluetooth adapter over which the Bluetooth connection will be made.
+  scoped_refptr<device::BluetoothAdapter> adapter_;
+
+  // The discovery session associated to this object.
+  scoped_ptr<device::BluetoothDiscoverySession> discovery_session_;
+
+  // True if there is a connection.
+  bool connected_;
+
+  // Callback called when the connection is established.
+  device::BluetoothDevice::GattConnectionCallback connection_callback_;
+
+  base::WeakPtrFactory<BluetoothLowEnergyConnectionFinder> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(BluetoothLowEnergyConnectionFinder);
+};
+
+}  // namespace proximity_auth
+
+#endif  // COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_CONNECTION_FINDER_H