// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <memory>
#include <unordered_map>

#include <fuchsia/bluetooth/le/cpp/fidl.h>
#include "lib/fidl/cpp/binding.h"
#include "lib/fxl/macros.h"

#include "garnet/drivers/bluetooth/host/fidl/server_base.h"
#include "garnet/drivers/bluetooth/host/gatt_host.h"
#include "garnet/drivers/bluetooth/lib/gap/low_energy_connection_manager.h"
#include "garnet/drivers/bluetooth/lib/gap/low_energy_discovery_manager.h"

namespace bthost {

// Implements the low_energy::Central FIDL interface.
class LowEnergyCentralServer
    : public AdapterServerBase<fuchsia::bluetooth::le::Central> {
 public:
  LowEnergyCentralServer(
      fxl::WeakPtr<::btlib::gap::Adapter> adapter,
      ::fidl::InterfaceRequest<fuchsia::bluetooth::le::Central> request,
      fbl::RefPtr<GattHost> gatt_host);
  ~LowEnergyCentralServer() override;

 private:
  // fuchsia::bluetooth::le::Central overrides:
  void GetPeripherals(::fidl::VectorPtr<::fidl::StringPtr> service_uuids,
                      GetPeripheralsCallback callback) override;
  void GetPeripheral(::fidl::StringPtr identifier,
                     GetPeripheralCallback callback) override;
  void StartScan(fuchsia::bluetooth::le::ScanFilterPtr filter,
                 StartScanCallback callback) override;
  void StopScan() override;
  void ConnectPeripheral(
      ::fidl::StringPtr identifier,
      ::fidl::InterfaceRequest<fuchsia::bluetooth::gatt::Client> client_request,
      ConnectPeripheralCallback callback) override;
  void DisconnectPeripheral(::fidl::StringPtr identifier,
                            DisconnectPeripheralCallback callback) override;

  // Called by |scan_session_| when a device is discovered.
  void OnScanResult(const ::btlib::gap::RemoteDevice& remote_device);

  // Notifies the delegate that the scan state for this Central has changed.
  void NotifyScanStateChanged(bool scanning);

  // Notifies the delegate that the device with the given identifier has been
  // disconnected.
  void NotifyPeripheralDisconnected(const std::string& identifier);

  // The GATT host is used to instantiate GATT Clients upon connection.
  fbl::RefPtr<GattHost> gatt_host_;

  // The currently active LE discovery session. This is initialized when a
  // client requests to perform a scan.
  bool requesting_scan_;
  std::unique_ptr<::btlib::gap::LowEnergyDiscoverySession> scan_session_;

  // This client's connection references. A client can hold a connection to
  // multiple peers. Each key is a remote device identifier. Each value is
  //   a. nullptr, if a connect request to this device is currently pending.
  //   b. a valid reference if this Central is holding a connection reference to
  //   this device.
  std::unordered_map<std::string, ::btlib::gap::LowEnergyConnectionRefPtr>
      connections_;

  // Keep this as the last member to make sure that all weak pointers are
  // invalidated before other members get destroyed.
  fxl::WeakPtrFactory<LowEnergyCentralServer> weak_ptr_factory_;

  FXL_DISALLOW_COPY_AND_ASSIGN(LowEnergyCentralServer);
};

}  // namespace bthost