// Copyright 2014 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 "extensions/browser/api/hid/hid_device_manager.h"

#include <stdint.h>

#include <limits>
#include <utility>
#include <vector>

#include "base/lazy_instance.h"
#include "base/location.h"
#include "base/memory/ptr_util.h"
#include "base/single_thread_task_runner.h"
#include "base/threading/thread_task_runner_handle.h"
#include "device/core/device_client.h"
#include "device/hid/hid_device_filter.h"
#include "device/hid/hid_service.h"
#include "extensions/browser/api/device_permissions_manager.h"
#include "extensions/common/permissions/permissions_data.h"
#include "extensions/common/permissions/usb_device_permission.h"

namespace hid = extensions::api::hid;

using device::HidDeviceFilter;
using device::HidDeviceId;
using device::HidDeviceInfo;
using device::HidService;

namespace extensions {

namespace {

void PopulateHidDeviceInfo(hid::HidDeviceInfo* output,
                           scoped_refptr<const HidDeviceInfo> input) {
  output->vendor_id = input->vendor_id();
  output->product_id = input->product_id();
  output->product_name = input->product_name();
  output->serial_number = input->serial_number();
  output->max_input_report_size = input->max_input_report_size();
  output->max_output_report_size = input->max_output_report_size();
  output->max_feature_report_size = input->max_feature_report_size();

  for (const device::HidCollectionInfo& collection : input->collections()) {
    // Don't expose sensitive data.
    if (collection.usage.IsProtected()) {
      continue;
    }

    hid::HidCollectionInfo api_collection;
    api_collection.usage_page = collection.usage.usage_page;
    api_collection.usage = collection.usage.usage;

    api_collection.report_ids.resize(collection.report_ids.size());
    std::copy(collection.report_ids.begin(), collection.report_ids.end(),
              api_collection.report_ids.begin());

    output->collections.push_back(std::move(api_collection));
  }

  const std::vector<uint8_t>& report_descriptor = input->report_descriptor();
  if (report_descriptor.size() > 0) {
    output->report_descriptor.assign(report_descriptor.begin(),
                                     report_descriptor.end());
  }
}

bool WillDispatchDeviceEvent(base::WeakPtr<HidDeviceManager> device_manager,
                             scoped_refptr<device::HidDeviceInfo> device_info,
                             content::BrowserContext* context,
                             const Extension* extension,
                             Event* event,
                             const base::DictionaryValue* listener_filter) {
  if (device_manager && extension) {
    return device_manager->HasPermission(extension, device_info, false);
  }
  return false;
}

}  // namespace

struct HidDeviceManager::GetApiDevicesParams {
 public:
  GetApiDevicesParams(const Extension* extension,
                      const std::vector<HidDeviceFilter>& filters,
                      const GetApiDevicesCallback& callback)
      : extension(extension), filters(filters), callback(callback) {}
  ~GetApiDevicesParams() {}

  const Extension* extension;
  std::vector<HidDeviceFilter> filters;
  GetApiDevicesCallback callback;
};

HidDeviceManager::HidDeviceManager(content::BrowserContext* context)
    : browser_context_(context),
      hid_service_observer_(this),
      weak_factory_(this) {
  event_router_ = EventRouter::Get(context);
  if (event_router_) {
    event_router_->RegisterObserver(this, hid::OnDeviceAdded::kEventName);
    event_router_->RegisterObserver(this, hid::OnDeviceRemoved::kEventName);
  }
}

HidDeviceManager::~HidDeviceManager() {
  DCHECK(thread_checker_.CalledOnValidThread());
}

// static
BrowserContextKeyedAPIFactory<HidDeviceManager>*
HidDeviceManager::GetFactoryInstance() {
  static base::LazyInstance<BrowserContextKeyedAPIFactory<HidDeviceManager> >
      factory = LAZY_INSTANCE_INITIALIZER;
  return &factory.Get();
}

void HidDeviceManager::GetApiDevices(
    const Extension* extension,
    const std::vector<HidDeviceFilter>& filters,
    const GetApiDevicesCallback& callback) {
  DCHECK(thread_checker_.CalledOnValidThread());
  LazyInitialize();

  if (enumeration_ready_) {
    std::unique_ptr<base::ListValue> devices =
        CreateApiDeviceList(extension, filters);
    base::ThreadTaskRunnerHandle::Get()->PostTask(
        FROM_HERE, base::Bind(callback, base::Passed(&devices)));
  } else {
    pending_enumerations_.push_back(base::WrapUnique(
        new GetApiDevicesParams(extension, filters, callback)));
  }
}

std::unique_ptr<base::ListValue> HidDeviceManager::GetApiDevicesFromList(
    const std::vector<scoped_refptr<HidDeviceInfo>>& devices) {
  DCHECK(thread_checker_.CalledOnValidThread());
  std::unique_ptr<base::ListValue> device_list(new base::ListValue());
  for (const auto& device : devices) {
    const auto device_entry = resource_ids_.find(device->device_id());
    DCHECK(device_entry != resource_ids_.end());

    hid::HidDeviceInfo device_info;
    device_info.device_id = device_entry->second;
    PopulateHidDeviceInfo(&device_info, device);
    device_list->Append(device_info.ToValue());
  }
  return device_list;
}

scoped_refptr<HidDeviceInfo> HidDeviceManager::GetDeviceInfo(int resource_id) {
  DCHECK(thread_checker_.CalledOnValidThread());
  HidService* hid_service = device::DeviceClient::Get()->GetHidService();
  DCHECK(hid_service);

  ResourceIdToDeviceIdMap::const_iterator device_iter =
      device_ids_.find(resource_id);
  if (device_iter == device_ids_.end()) {
    return nullptr;
  }

  return hid_service->GetDeviceInfo(device_iter->second);
}

bool HidDeviceManager::HasPermission(const Extension* extension,
                                     scoped_refptr<HidDeviceInfo> device_info,
                                     bool update_last_used) {
  DevicePermissionsManager* permissions_manager =
      DevicePermissionsManager::Get(browser_context_);
  CHECK(permissions_manager);
  DevicePermissions* device_permissions =
      permissions_manager->GetForExtension(extension->id());
  DCHECK(device_permissions);
  scoped_refptr<DevicePermissionEntry> permission_entry =
      device_permissions->FindHidDeviceEntry(device_info);
  if (permission_entry) {
    if (update_last_used) {
      permissions_manager->UpdateLastUsed(extension->id(), permission_entry);
    }
    return true;
  }

  UsbDevicePermission::CheckParam usbParam(
      device_info->vendor_id(), device_info->product_id(),
      UsbDevicePermissionData::UNSPECIFIED_INTERFACE);
  if (extension->permissions_data()->CheckAPIPermissionWithParam(
          APIPermission::kUsbDevice, &usbParam)) {
    return true;
  }

  if (extension->permissions_data()->HasAPIPermission(
          APIPermission::kU2fDevices)) {
    HidDeviceFilter u2f_filter;
    u2f_filter.SetUsagePage(0xF1D0);
    if (u2f_filter.Matches(device_info)) {
      return true;
    }
  }

  return false;
}

void HidDeviceManager::Shutdown() {
  if (event_router_) {
    event_router_->UnregisterObserver(this);
  }
}

void HidDeviceManager::OnListenerAdded(const EventListenerInfo& details) {
  LazyInitialize();
}

void HidDeviceManager::OnDeviceAdded(scoped_refptr<HidDeviceInfo> device_info) {
  DCHECK(thread_checker_.CalledOnValidThread());
  DCHECK_LT(next_resource_id_, std::numeric_limits<int>::max());
  int new_id = next_resource_id_++;
  DCHECK(!ContainsKey(resource_ids_, device_info->device_id()));
  resource_ids_[device_info->device_id()] = new_id;
  device_ids_[new_id] = device_info->device_id();

  // Don't generate events during the initial enumeration.
  if (enumeration_ready_ && event_router_) {
    api::hid::HidDeviceInfo api_device_info;
    api_device_info.device_id = new_id;
    PopulateHidDeviceInfo(&api_device_info, device_info);

    if (api_device_info.collections.size() > 0) {
      std::unique_ptr<base::ListValue> args(
          hid::OnDeviceAdded::Create(api_device_info));
      DispatchEvent(events::HID_ON_DEVICE_ADDED, hid::OnDeviceAdded::kEventName,
                    std::move(args), device_info);
    }
  }
}

void HidDeviceManager::OnDeviceRemoved(
    scoped_refptr<HidDeviceInfo> device_info) {
  DCHECK(thread_checker_.CalledOnValidThread());
  const auto& resource_entry = resource_ids_.find(device_info->device_id());
  DCHECK(resource_entry != resource_ids_.end());
  int resource_id = resource_entry->second;
  const auto& device_entry = device_ids_.find(resource_id);
  DCHECK(device_entry != device_ids_.end());
  resource_ids_.erase(resource_entry);
  device_ids_.erase(device_entry);

  if (event_router_) {
    DCHECK(enumeration_ready_);
    std::unique_ptr<base::ListValue> args(
        hid::OnDeviceRemoved::Create(resource_id));
    DispatchEvent(events::HID_ON_DEVICE_REMOVED,
                  hid::OnDeviceRemoved::kEventName, std::move(args),
                  device_info);
  }
}

void HidDeviceManager::LazyInitialize() {
  DCHECK(thread_checker_.CalledOnValidThread());

  if (initialized_) {
    return;
  }

  HidService* hid_service = device::DeviceClient::Get()->GetHidService();
  DCHECK(hid_service);
  hid_service->GetDevices(base::Bind(&HidDeviceManager::OnEnumerationComplete,
                                     weak_factory_.GetWeakPtr()));

  hid_service_observer_.Add(hid_service);
  initialized_ = true;
}

std::unique_ptr<base::ListValue> HidDeviceManager::CreateApiDeviceList(
    const Extension* extension,
    const std::vector<HidDeviceFilter>& filters) {
  HidService* hid_service = device::DeviceClient::Get()->GetHidService();
  DCHECK(hid_service);

  std::unique_ptr<base::ListValue> api_devices(new base::ListValue());
  for (const ResourceIdToDeviceIdMap::value_type& map_entry : device_ids_) {
    int resource_id = map_entry.first;
    const HidDeviceId& device_id = map_entry.second;

    scoped_refptr<HidDeviceInfo> device_info =
        hid_service->GetDeviceInfo(device_id);
    if (!device_info) {
      continue;
    }

    if (!filters.empty() &&
        !HidDeviceFilter::MatchesAny(device_info, filters)) {
      continue;
    }

    if (!HasPermission(extension, device_info, false)) {
      continue;
    }

    hid::HidDeviceInfo api_device_info;
    api_device_info.device_id = resource_id;
    PopulateHidDeviceInfo(&api_device_info, device_info);

    // Expose devices with which user can communicate.
    if (api_device_info.collections.size() > 0) {
      api_devices->Append(api_device_info.ToValue());
    }
  }

  return api_devices;
}

void HidDeviceManager::OnEnumerationComplete(
    const std::vector<scoped_refptr<HidDeviceInfo>>& devices) {
  DCHECK(resource_ids_.empty());
  DCHECK(device_ids_.empty());
  for (const scoped_refptr<HidDeviceInfo>& device_info : devices) {
    OnDeviceAdded(device_info);
  }
  enumeration_ready_ = true;

  for (const auto& params : pending_enumerations_) {
    std::unique_ptr<base::ListValue> devices =
        CreateApiDeviceList(params->extension, params->filters);
    params->callback.Run(std::move(devices));
  }
  pending_enumerations_.clear();
}

void HidDeviceManager::DispatchEvent(
    events::HistogramValue histogram_value,
    const std::string& event_name,
    std::unique_ptr<base::ListValue> event_args,
    scoped_refptr<HidDeviceInfo> device_info) {
  std::unique_ptr<Event> event(
      new Event(histogram_value, event_name, std::move(event_args)));
  event->will_dispatch_callback = base::Bind(
      &WillDispatchDeviceEvent, weak_factory_.GetWeakPtr(), device_info);
  event_router_->BroadcastEvent(std::move(event));
}

}  // namespace extensions