chromium/src/third_party/blink/renderer/core/input/gesture_manager.h

// Copyright 2016 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.

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_INPUT_GESTURE_MANAGER_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_INPUT_GESTURE_MANAGER_H_

#include "third_party/blink/public/platform/web_input_event_result.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/layout/hit_test_request.h"
#include "third_party/blink/renderer/core/page/event_with_hit_test_results.h"

namespace blink {

class IntPoint;
class LocalFrame;
class ScrollManager;
class SelectionController;
class PointerEventManager;
class MouseEventManager;

// This class takes care of gestures and delegating the action based on the
// gesture to the responsible class.
class CORE_EXPORT GestureManager final
    : public GarbageCollected<GestureManager> {
 public:
  GestureManager(LocalFrame&,
                 ScrollManager&,
                 MouseEventManager&,
                 PointerEventManager&,
                 SelectionController&);
  GestureManager(const GestureManager&) = delete;
  GestureManager& operator=(const GestureManager&) = delete;
  void Trace(Visitor*) const;

  void Clear();
  void ResetLongTapContextMenuStates();

  HitTestRequest::HitTestRequestType GetHitTypeForGestureType(
      WebInputEvent::Type);
  WebInputEventResult HandleGestureEventInFrame(
      const GestureEventWithHitTestResults&);
  bool GestureContextMenuDeferred() const;

  // Dispatches contextmenu event for drag-ends that haven't really dragged
  // except for a few pixels.
  //
  // The reason for handling this in GestureManager is the similarity of the
  // interaction with long taps.  When a drag ends without a drag offset, it is
  // effectively a long tap but with one difference: there is no gesture long
  // tap event.  This is because the drag controller interrupts current gesture
  // sequence (cancelling the gesture) at the moment a drag begins, and the
  // gesture recognizer does not know if the drag has ended at the originating
  // position.
  void SendContextMenuEventTouchDragEnd(const WebMouseEvent&);

 private:
  WebInputEventResult HandleGestureShowPress();
  WebInputEventResult HandleGestureTapDown(
      const GestureEventWithHitTestResults&);
  WebInputEventResult HandleGestureTap(const GestureEventWithHitTestResults&);
  WebInputEventResult HandleGestureLongPress(
      const GestureEventWithHitTestResults&);
  WebInputEventResult HandleGestureLongTap(
      const GestureEventWithHitTestResults&);
  WebInputEventResult HandleGestureTwoFingerTap(
      const GestureEventWithHitTestResults&);

  WebInputEventResult SendContextMenuEventForGesture(
      const GestureEventWithHitTestResults&);
  // Shows the Unhandled Tap UI if needed.
  void ShowUnhandledTapUIIfNeeded(bool dom_tree_changed,
                                  bool style_changed,
                                  Node* tapped_node,
                                  Element* tapped_element,
                                  const IntPoint& tapped_position_in_viewport);

  // NOTE: If adding a new field to this class please ensure that it is
  // cleared if needed in |GestureManager::clear()|.

  const Member<LocalFrame> frame_;

  Member<ScrollManager> scroll_manager_;
  Member<MouseEventManager> mouse_event_manager_;
  Member<PointerEventManager> pointer_event_manager_;

  // Set on GestureTapDown if the |pointerdown| event corresponding to the
  // triggering |touchstart| event was canceled. This suppresses mouse event
  // firing for the current gesture sequence (i.e. until next GestureTapDown).
  bool suppress_mouse_events_from_gestures_;

  bool gesture_context_menu_deferred_;

  gfx::PointF long_press_position_in_root_frame_;

  const Member<SelectionController> selection_controller_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_INPUT_GESTURE_MANAGER_H_