chrome/browser/image_editor/event_capture_mac.h

// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_IMAGE_EDITOR_EVENT_CAPTURE_MAC_H_
#define CHROME_BROWSER_IMAGE_EDITOR_EVENT_CAPTURE_MAC_H_

#include <memory>

#include "base/functional/callback.h"
#include "base/memory/weak_ptr.h"
#include "ui/events/event_handler.h"
#include "ui/gfx/native_widget_types.h"

namespace image_editor {

// A class to capture mouse events on Mac and forward them to an event handler.
// For other platforms we attach a pre-target handler to the main WebContents's
// NativeWindow and can catch and consume events there, but some events over
// the main window do not reach that approach on Mac.
class EventCaptureMac {
 public:
  EventCaptureMac(ui::EventHandler* event_handler,
                  base::OnceClosure capture_lost_callback,
                  gfx::NativeView web_contents_view,
                  gfx::NativeWindow target_window);
  ~EventCaptureMac();
  EventCaptureMac(const EventCaptureMac&) = delete;
  EventCaptureMac& operator=(const EventCaptureMac&) = delete;

  // Allows mouse move events over the affected region requests to set a cross
  // cursor, using a native method.
  static void SetCrossCursor();

 private:
  // Mouse capture uses CocoaMouseCapture. We create a narrow
  // local event monitor with NSEventMaskKeyDown, to only listen
  // for keydown events and detect ESC to close the capture scrim.
  void CreateKeyDownLocalMonitor(ui::EventHandler* event_handler,
                                 gfx::NativeWindow target_native_window);

  class MouseCaptureDelegateImpl;
  std::unique_ptr<MouseCaptureDelegateImpl> mouse_capture_delegate_impl_;

  base::WeakPtrFactory<EventCaptureMac> factory_{this};
};

}  // namespace image_editor

#endif  // CHROME_BROWSER_IMAGE_EDITOR_EVENT_CAPTURE_MAC_H_