third_party/WebKit/Source/core/events/TreeScopeEventContext.cpp

/*
 * Copyright (C) 2014 Google Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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#include "core/events/TreeScopeEventContext.h"

#include "core/dom/StaticNodeList.h"
#include "core/dom/shadow/ShadowRoot.h"
#include "core/events/EventPath.h"
#include "core/events/TouchEventContext.h"

namespace blink {

bool TreeScopeEventContext::isUnclosedTreeOf(
    const TreeScopeEventContext& other) {
  // Exclude closed nodes if necessary.
  // If a node is in a closed shadow root, or in a tree whose ancestor has a
  // closed shadow root, it should not be visible to nodes above the closed
  // shadow root.

  // (1) If |this| is an ancestor of |other| in tree-of-trees, include it.
  if (isInclusiveAncestorOf(other))
    return true;

  // (2) If no closed shadow root in ancestors of this, include it.
  if (!containingClosedShadowTree())
    return true;

  // (3) If |this| is descendent of |other|, exclude if any closed shadow root
  // in between.
  if (isDescendantOf(other))
    return !containingClosedShadowTree()->isDescendantOf(other);

// (4) |this| and |other| must be in exclusive branches.
#if DCHECK_IS_ON()
  DCHECK(other.isExclusivePartOf(*this));
#endif
  return false;
}

HeapVector<Member<EventTarget>>& TreeScopeEventContext::ensureEventPath(
    EventPath& path) {
  if (m_eventPath)
    return *m_eventPath;

  m_eventPath = new HeapVector<Member<EventTarget>>();
  LocalDOMWindow* window = path.windowEventContext().window();
  m_eventPath->reserveCapacity(path.size() + (window ? 1 : 0));

  for (size_t i = 0; i < path.size(); ++i) {
    if (path[i].treeScopeEventContext().isUnclosedTreeOf(*this))
      m_eventPath->append(path[i].node());
  }
  if (window)
    m_eventPath->append(window);
  return *m_eventPath;
}

TouchEventContext* TreeScopeEventContext::ensureTouchEventContext() {
  if (!m_touchEventContext)
    m_touchEventContext = TouchEventContext::create();
  return m_touchEventContext.get();
}

TreeScopeEventContext* TreeScopeEventContext::create(TreeScope& treeScope) {
  return new TreeScopeEventContext(treeScope);
}

TreeScopeEventContext::TreeScopeEventContext(TreeScope& treeScope)
    : m_treeScope(treeScope),
      m_rootNode(treeScope.rootNode()),
      m_containingClosedShadowTree(nullptr),
      m_preOrder(-1),
      m_postOrder(-1) {}

DEFINE_TRACE(TreeScopeEventContext) {
  visitor->trace(m_treeScope);
  visitor->trace(m_rootNode);
  visitor->trace(m_target);
  visitor->trace(m_relatedTarget);
  visitor->trace(m_eventPath);
  visitor->trace(m_touchEventContext);
  visitor->trace(m_containingClosedShadowTree);
  visitor->trace(m_children);
}

int TreeScopeEventContext::calculateTreeOrderAndSetNearestAncestorClosedTree(
    int orderNumber,
    TreeScopeEventContext* nearestAncestorClosedTreeScopeEventContext) {
  m_preOrder = orderNumber;
  m_containingClosedShadowTree =
      (rootNode().isShadowRoot() && !toShadowRoot(rootNode()).isOpenOrV0())
          ? this
          : nearestAncestorClosedTreeScopeEventContext;
  for (size_t i = 0; i < m_children.size(); ++i)
    orderNumber =
        m_children[i]->calculateTreeOrderAndSetNearestAncestorClosedTree(
            orderNumber + 1, containingClosedShadowTree());
  m_postOrder = orderNumber + 1;

  return orderNumber + 1;
}

}  // namespace blink