content/browser/renderer_host/input/touch_selection_controller.h

// 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.

#ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCH_SELECTION_CONTROLLER_H_
#define CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCH_SELECTION_CONTROLLER_H_

#include "content/browser/renderer_host/input/selection_event_type.h"
#include "content/browser/renderer_host/input/touch_handle.h"
#include "content/common/content_export.h"
#include "ui/gfx/geometry/point_f.h"
#include "ui/gfx/geometry/rect_f.h"

namespace blink {
class WebInputEvent;
}

namespace ui {
class MotionEvent;
}

namespace content {

// Interface through which |TouchSelectionController| issues selection-related
// commands, notifications and requests.
class CONTENT_EXPORT TouchSelectionControllerClient {
 public:
  virtual ~TouchSelectionControllerClient() {}

  virtual bool SupportsAnimation() const = 0;
  virtual void SetNeedsAnimate() = 0;
  virtual void MoveCaret(const gfx::PointF& position) = 0;
  virtual void SelectBetweenCoordinates(const gfx::PointF& start,
                                        const gfx::PointF& end) = 0;
  virtual void OnSelectionEvent(SelectionEventType event,
                                const gfx::PointF& position) = 0;
  virtual scoped_ptr<TouchHandleDrawable> CreateDrawable() = 0;
};

// Controller for manipulating text selection via touch input.
class CONTENT_EXPORT TouchSelectionController : public TouchHandleClient {
 public:
  explicit TouchSelectionController(TouchSelectionControllerClient* client);
  virtual ~TouchSelectionController();

  // To be called when the selection bounds have changed.
  // Note that such updates will trigger handle updates only if preceded
  // by an appropriate call to allow automatic showing.
  void OnSelectionBoundsChanged(const gfx::RectF& start_rect,
                                TouchHandleOrientation start_orientation,
                                bool start_visible,
                                const gfx::RectF& end_rect,
                                TouchHandleOrientation end_orientation,
                                bool end_visible);

  // Allows touch-dragging of the handle.
  // Returns true iff the event was consumed, in which case the caller should
  // cease further handling of the event.
  bool WillHandleTouchEvent(const ui::MotionEvent& event);

  // Allow the insertion or selection handles to be shown from the data
  // in |OnSelectionBoundsChanged()|.
  void ShowInsertionHandleAutomatically();
  void ShowSelectionHandlesAutomatically();

  // Hide the handles and suppress bounds updates until the next explicit
  // showing allowance.
  void HideAndDisallowAutomaticShowing();

  // Override the handle visibility according to |hidden|.
  void SetTemporarilyHidden(bool hidden);

  // To be called when the editability of the focused region changes.
  void OnSelectionEditable(bool editable);

  // Ticks an active animation, as requested to the client by |SetNeedsAnimate|.
  // Returns true if an animation is active and requires further ticking.
  bool Animate(base::TimeTicks animate_time);

 private:
  // TouchHandleClient implementation.
  virtual void OnHandleDragBegin(const TouchHandle& handle) OVERRIDE;
  virtual void OnHandleDragUpdate(const TouchHandle& handle,
                                  const gfx::PointF& new_position) OVERRIDE;
  virtual void OnHandleDragEnd(const TouchHandle& handle) OVERRIDE;
  virtual void OnHandleTapped(const TouchHandle& handle) OVERRIDE;
  virtual void SetNeedsAnimate() OVERRIDE;
  virtual scoped_ptr<TouchHandleDrawable> CreateDrawable() OVERRIDE;

  void OnInsertionChanged();
  void OnSelectionChanged();

  void ActivateInsertion();
  void DeactivateInsertion();
  void ActivateSelection();
  void DeactivateSelection();
  void ResetCachedValues();

  gfx::PointF GetStartPosition() const;
  gfx::PointF GetEndPosition() const;
  float GetStartLineHeight() const;
  float GetEndLineHeight() const;
  bool GetStartVisible() const;
  bool GetEndVisible() const;
  TouchHandle::AnimationStyle GetAnimationStyle(bool was_active) const;

  TouchSelectionControllerClient* const client_;

  gfx::RectF start_rect_;
  TouchHandleOrientation start_orientation_;
  bool start_visible_;
  gfx::RectF end_rect_;
  TouchHandleOrientation end_orientation_;
  bool end_visible_;

  scoped_ptr<TouchHandle> insertion_handle_;
  bool is_insertion_active_;
  bool activate_insertion_automatically_;

  scoped_ptr<TouchHandle> start_selection_handle_;
  scoped_ptr<TouchHandle> end_selection_handle_;
  gfx::PointF fixed_handle_position_;
  bool is_selection_active_;
  bool activate_selection_automatically_;

  bool selection_editable_;
  bool selection_editable_for_last_update_;

  bool temporarily_hidden_;

  DISALLOW_COPY_AND_ASSIGN(TouchSelectionController);
};

}  // namespace content

#endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_TOUCH_SELECTION_CONTROLLER_H_