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/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009 Apple Inc.
* All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
// Copyright 2017 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_HTML_LIST_ITEM_ORDINAL_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_HTML_LIST_ITEM_ORDINAL_H_
#include "base/optional.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/platform/heap/persistent.h"
namespace blink {
class HTMLOListElement;
class LayoutObject;
class Node;
// Represents an "ordinal value" and its related algorithms:
// https://html.spec.whatwg.org/C/#ordinal-value
//
// The ordinal value is determined by the DOM tree order. However, since any
// elements with 'display: list-item' can be list items, the layout tree
// provides the storage for the instances of this class, and is responsible for
// firing events for insertions and removals.
class CORE_EXPORT ListItemOrdinal {
public:
ListItemOrdinal();
// Get the corresponding instance for a node.
static ListItemOrdinal* Get(const Node&);
// Get the "ordinal value".
int Value(const Node&) const;
// Get/set/clear the explicit value; i.e., the 'value' attribute of an <li>
// element.
base::Optional<int> ExplicitValue() const;
void SetExplicitValue(int, const Node&);
void ClearExplicitValue(const Node&);
static bool IsList(const Node&);
static bool IsListItem(const Node&);
static bool IsListItem(const LayoutObject*);
// Compute the total item count of a list.
static unsigned ItemCountForOrderedList(const HTMLOListElement*);
// Invalidate all ordinal values of a list.
static void InvalidateAllItemsForOrderedList(const HTMLOListElement*);
// Invalidate items that are affected by an insertion or a removal.
static void ItemInsertedOrRemoved(const LayoutObject*);
private:
enum ValueType { kNeedsUpdate, kUpdated, kExplicit };
ValueType Type() const { return static_cast<ValueType>(type_); }
void SetType(ValueType type) const { type_ = type; }
bool HasExplicitValue() const { return type_ == kExplicit; }
static Node* EnclosingList(const Node*);
struct NodeAndOrdinal {
STACK_ALLOCATED();
public:
Persistent<const Node> node;
ListItemOrdinal* ordinal = nullptr;
operator bool() const { return node; }
};
static NodeAndOrdinal NextListItem(const Node* list_node,
const Node* item_node = nullptr);
static NodeAndOrdinal PreviousListItem(const Node* list_node,
const Node* item_node);
static NodeAndOrdinal NextOrdinalItem(bool is_reversed,
const Node* list_node,
const Node* item_node = nullptr);
int CalcValue(const Node&) const;
void InvalidateSelf(const Node&, ValueType = kNeedsUpdate);
static void InvalidateAfter(const Node* list_node, const Node* item_node);
static void InvalidateOrdinalsAfter(bool is_reversed,
const Node* list_node,
const Node* item_node);
mutable int value_ = 0;
mutable unsigned type_ : 2; // ValueType
};
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_CORE_HTML_LIST_ITEM_ORDINAL_H_
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