chrome/browser/vr/service/vr_device_manager.cc

// 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.

#include "chrome/browser/vr/service/vr_device_manager.h"

#include <utility>

#include "base/bind.h"
#include "base/memory/ptr_util.h"
#include "base/memory/singleton.h"
#include "build/build_config.h"
#include "chrome/common/chrome_features.h"
#include "device/vr/features/features.h"
#include "device/vr/vr_device_provider.h"

#if defined(OS_ANDROID)
#include "device/vr/android/gvr/gvr_device_provider.h"
#endif

#if BUILDFLAG(ENABLE_OPENVR)
#include "device/vr/openvr/openvr_device_provider.h"
#endif

namespace vr {

namespace {
VRDeviceManager* g_vr_device_manager = nullptr;
}

VRDeviceManager* VRDeviceManager::GetInstance() {
  if (!g_vr_device_manager) {
    // Register VRDeviceProviders for the current platform
    ProviderList providers;
#if defined(OS_ANDROID)
    providers.emplace_back(std::make_unique<device::GvrDeviceProvider>());
#endif

#if BUILDFLAG(ENABLE_OPENVR)
    if (base::FeatureList::IsEnabled(features::kOpenVR))
      providers.emplace_back(std::make_unique<device::OpenVRDeviceProvider>());
#endif
    new VRDeviceManager(std::move(providers));
  }
  return g_vr_device_manager;
}

bool VRDeviceManager::HasInstance() {
  return g_vr_device_manager != nullptr;
}

VRDeviceManager::VRDeviceManager(ProviderList providers)
    : providers_(std::move(providers)) {
  CHECK(!g_vr_device_manager);
  g_vr_device_manager = this;
}

VRDeviceManager::~VRDeviceManager() {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  g_vr_device_manager = nullptr;
}

void VRDeviceManager::AddService(VRServiceImpl* service) {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);

  // Loop through any currently active devices and send Connected messages to
  // the service. Future devices that come online will send a Connected message
  // when they are created.
  InitializeProviders();

  for (const DeviceMap::value_type& map_entry : devices_)
    service->ConnectDevice(map_entry.second);

  if (AreAllProvidersInitialized())
    service->InitializationComplete();

  services_.insert(service);
}

void VRDeviceManager::RemoveService(VRServiceImpl* service) {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  services_.erase(service);

  if (services_.empty()) {
    // Delete the device manager when it has no active connections.
    delete g_vr_device_manager;
  }
}

void VRDeviceManager::AddDevice(device::VRDevice* device) {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  DCHECK(devices_.find(device->GetId()) == devices_.end());
  // Ignore any devices with VR_DEVICE_LAST_ID, which is used to prevent
  // wraparound of device ids.
  if (device->GetId() == device::VR_DEVICE_LAST_ID)
    return;

  devices_[device->GetId()] = device;
  for (VRServiceImpl* service : services_)
    service->ConnectDevice(device);
}

void VRDeviceManager::RemoveDevice(device::VRDevice* device) {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  if (device->GetId() == device::VR_DEVICE_LAST_ID)
    return;
  auto it = devices_.find(device->GetId());
  DCHECK(it != devices_.end());

  for (VRServiceImpl* service : services_)
    service->RemoveDevice(device);

  devices_.erase(it);
}

device::VRDevice* VRDeviceManager::GetDevice(unsigned int index) {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);

  if (index == 0)
    return nullptr;

  DeviceMap::iterator iter = devices_.find(index);
  if (iter == devices_.end())
    return nullptr;

  return iter->second;
}

void VRDeviceManager::InitializeProviders() {
  if (providers_initialized_)
    return;

  for (const auto& provider : providers_) {
    provider->Initialize(
        base::Bind(&VRDeviceManager::AddDevice, base::Unretained(this)),
        base::Bind(&VRDeviceManager::RemoveDevice, base::Unretained(this)),
        base::BindOnce(&VRDeviceManager::OnProviderInitialized,
                       base::Unretained(this)));
  }

  providers_initialized_ = true;
}

void VRDeviceManager::OnProviderInitialized() {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  ++num_initialized_providers_;
  if (AreAllProvidersInitialized()) {
    for (VRServiceImpl* service : services_)
      service->InitializationComplete();
  }
}

bool VRDeviceManager::AreAllProvidersInitialized() {
  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
  return num_initialized_providers_ == providers_.size();
}

size_t VRDeviceManager::NumberOfConnectedServices() {
  return services_.size();
}

}  // namespace vr