text: // 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 "ui/events/device_data_manager.h"
  
  #include "base/at_exit.h"
  #include "base/bind.h"
  #include "base/logging.h"
  #include "ui/events/input_device_event_observer.h"
  #include "ui/gfx/display.h"
  #include "ui/gfx/geometry/point3_f.h"
  
  namespace ui {
  
  // static
  DeviceDataManager* DeviceDataManager::instance_ = NULL;
  
  DeviceDataManager::DeviceDataManager() {
    CHECK(!instance_) << "Can not create multiple instances of DeviceDataManager";
    instance_ = this;
  
    base::AtExitManager::RegisterTask(
        base::Bind(&base::DeletePointer<DeviceDataManager>, this));
  
    for (int i = 0; i < kMaxDeviceNum; ++i) {
      touch_device_to_display_map_[i] = gfx::Display::kInvalidDisplayID;
      touch_radius_scale_map_[i] = 1.0;
    }
  }
  
  DeviceDataManager::~DeviceDataManager() {
    CHECK_EQ(this, instance_);
    instance_ = NULL;
  }
  
  // static
  DeviceDataManager* DeviceDataManager::instance() { return instance_; }
  
  // static
  void DeviceDataManager::CreateInstance() {
    if (instance())
      return;
  
    new DeviceDataManager();
  }
  
  // static
  DeviceDataManager* DeviceDataManager::GetInstance() {
    CHECK(instance_) << "DeviceDataManager was not created.";
    return instance_;
  }
  
  // static
  bool DeviceDataManager::HasInstance() {
    return instance_ != NULL;
  }
  
  void DeviceDataManager::ClearTouchTransformerRecord() {
    for (int i = 0; i < kMaxDeviceNum; i++) {
      touch_device_transformer_map_[i] = gfx::Transform();
      touch_device_to_display_map_[i] = gfx::Display::kInvalidDisplayID;
      touch_radius_scale_map_[i] = 1.0;
    }
  }
  
  bool DeviceDataManager::IsTouchDeviceIdValid(int touch_device_id) const {
    return (touch_device_id > 0 && touch_device_id < kMaxDeviceNum);
  }
  
  void DeviceDataManager::UpdateTouchInfoForDisplay(
      int64_t display_id,
      int touch_device_id,
      const gfx::Transform& touch_transformer) {
    if (IsTouchDeviceIdValid(touch_device_id)) {
      touch_device_to_display_map_[touch_device_id] = display_id;
      touch_device_transformer_map_[touch_device_id] = touch_transformer;
    }
  }
  
  void DeviceDataManager::UpdateTouchRadiusScale(int touch_device_id,
                                                 double scale) {
    if (IsTouchDeviceIdValid(touch_device_id))
      touch_radius_scale_map_[touch_device_id] = scale;
  }
  
  void DeviceDataManager::ApplyTouchRadiusScale(int touch_device_id,
                                                double* radius) {
    if (IsTouchDeviceIdValid(touch_device_id))
      *radius = (*radius) * touch_radius_scale_map_[touch_device_id];
  }
  
  void DeviceDataManager::ApplyTouchTransformer(int touch_device_id,
                                                float* x,
                                                float* y) {
    if (IsTouchDeviceIdValid(touch_device_id)) {
      gfx::Point3F point(*x, *y, 0.0);
      const gfx::Transform& trans =
          touch_device_transformer_map_[touch_device_id];
      trans.TransformPoint(&point);
      *x = point.x();
      *y = point.y();
    }
  }
  
  int64_t DeviceDataManager::GetDisplayForTouchDevice(int touch_device_id) const {
    if (IsTouchDeviceIdValid(touch_device_id))
      return touch_device_to_display_map_[touch_device_id];
    return gfx::Display::kInvalidDisplayID;
  }
  
  void DeviceDataManager::OnTouchscreenDevicesUpdated(
      const std::vector<TouchscreenDevice>& devices) {
    touchscreen_devices_ = devices;
  
    FOR_EACH_OBSERVER(InputDeviceEventObserver,
                      observers_,
                      OnInputDeviceConfigurationChanged());
  }
  
  void DeviceDataManager::AddObserver(InputDeviceEventObserver* observer) {
    observers_.AddObserver(observer);
  }
  
  void DeviceDataManager::RemoveObserver(InputDeviceEventObserver* observer) {
    observers_.RemoveObserver(observer);
  }
  
  }  // namespace ui
  