node_holder.h

// Copyright 2019 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 CC_PAINT_NODE_HOLDER_H_
#define CC_PAINT_NODE_HOLDER_H_

#include "base/memory/scoped_refptr.h"
#include "cc/paint/paint_export.h"
#include "cc/paint/text_holder.h"

namespace cc {

// This struct is used to hold the information of node that PaintOp associates
// with, either the TextHolder or the Id could be set, but only one will finally
// be supported base on the performance impact.
// This is used for ContentCapture in blink to capture on-screen content, the
// NodeHolder shall be set to DrawTextBlobOp when blink paints the main text
// content of page; for ContentCapture, please refer to
// third_party/blink/renderer/core/content_capture/README.md
struct CC_PAINT_EXPORT NodeHolder {
  NodeHolder();
  explicit NodeHolder(scoped_refptr<TextHolder> text_holder);
  explicit NodeHolder(int id);
  NodeHolder(const NodeHolder& node_holder);
  virtual ~NodeHolder();

  // Returns the empty NodeHolder, shall be used for content that is not
  // considered part of the main text content of the page.
  static const NodeHolder& EmptyNodeHolder();

  enum class Type : bool { kTextHolder = false, kID = true };

  // Only valid if is_empty is false.
  scoped_refptr<TextHolder> text_holder;
  int id;
  Type type;
  bool is_empty;
};

bool operator==(const NodeHolder& l, const NodeHolder& r);

bool operator!=(const NodeHolder& l, const NodeHolder& r);

}  // namespace cc

#endif  // CC_PAINT_NODE_HOLDER_H_