third_party/WebKit/Source/core/page/CustomContextMenuProvider.cpp

// 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.

#include "core/page/CustomContextMenuProvider.h"

#include "core/dom/Document.h"
#include "core/dom/ElementTraversal.h"
#include "core/events/EventDispatcher.h"
#include "core/events/MouseEvent.h"
#include "core/html/HTMLMenuElement.h"
#include "core/html/HTMLMenuItemElement.h"
#include "core/page/ContextMenuController.h"
#include "core/page/Page.h"
#include "platform/ContextMenu.h"

namespace blink {

using namespace HTMLNames;

CustomContextMenuProvider::CustomContextMenuProvider(HTMLMenuElement& menu,
                                                     HTMLElement& subject)
    : m_menu(menu), m_subjectElement(subject) {}

CustomContextMenuProvider::~CustomContextMenuProvider() {}

DEFINE_TRACE(CustomContextMenuProvider) {
  visitor->trace(m_menu);
  visitor->trace(m_subjectElement);
  visitor->trace(m_menuItems);
  ContextMenuProvider::trace(visitor);
}

void CustomContextMenuProvider::populateContextMenu(ContextMenu* menu) {
  populateContextMenuItems(*m_menu, *menu);
}

void CustomContextMenuProvider::contextMenuItemSelected(
    const ContextMenuItem* item) {
  if (HTMLElement* element = menuItemAt(item->action())) {
    MouseEvent* click = MouseEvent::create(
        EventTypeNames::click, m_menu->document().domWindow(), Event::create(),
        SimulatedClickCreationScope::FromUserAgent);
    click->setRelatedTarget(m_subjectElement.get());
    element->dispatchEvent(click);
  }
}

void CustomContextMenuProvider::contextMenuCleared() {
  m_menuItems.clear();
  m_subjectElement = nullptr;
}

void CustomContextMenuProvider::appendSeparator(ContextMenu& contextMenu) {
  // Avoid separators at the start of any menu and submenu.
  if (!contextMenu.items().size())
    return;

  // Collapse all sequences of two or more adjacent separators in the menu or
  // any submenus to a single separator.
  ContextMenuItem lastItem = contextMenu.items().last();
  if (lastItem.type() == SeparatorType)
    return;

  contextMenu.appendItem(ContextMenuItem(
      SeparatorType, ContextMenuItemCustomTagNoAction, String(), String()));
}

void CustomContextMenuProvider::appendMenuItem(HTMLMenuItemElement* menuItem,
                                               ContextMenu& contextMenu) {
  // Avoid menuitems with no label.
  String labelString = menuItem->fastGetAttribute(labelAttr);
  if (labelString.isEmpty())
    return;

  m_menuItems.append(menuItem);

  bool enabled = !menuItem->fastHasAttribute(disabledAttr);
  String icon = menuItem->fastGetAttribute(iconAttr);
  if (!icon.isEmpty()) {
    // To obtain the absolute URL of the icon when the attribute's value is not
    // the empty string, the attribute's value must be resolved relative to the
    // element.
    KURL iconURL = KURL(menuItem->baseURI(), icon);
    icon = iconURL.getString();
  }
  ContextMenuAction action = static_cast<ContextMenuAction>(
      ContextMenuItemBaseCustomTag + m_menuItems.size() - 1);
  if (equalIgnoringCase(menuItem->fastGetAttribute(typeAttr), "checkbox") ||
      equalIgnoringCase(menuItem->fastGetAttribute(typeAttr), "radio"))
    contextMenu.appendItem(
        ContextMenuItem(CheckableActionType, action, labelString, icon, enabled,
                        menuItem->fastHasAttribute(checkedAttr)));
  else
    contextMenu.appendItem(
        ContextMenuItem(ActionType, action, labelString, icon, enabled, false));
}

void CustomContextMenuProvider::populateContextMenuItems(
    const HTMLMenuElement& menu,
    ContextMenu& contextMenu) {
  HTMLElement* nextElement = Traversal<HTMLElement>::firstWithin(menu);
  while (nextElement) {
    if (isHTMLHRElement(*nextElement)) {
      appendSeparator(contextMenu);
      nextElement = Traversal<HTMLElement>::next(*nextElement, &menu);
    } else if (isHTMLMenuElement(*nextElement)) {
      ContextMenu subMenu;
      String labelString = nextElement->fastGetAttribute(labelAttr);
      if (labelString.isNull()) {
        appendSeparator(contextMenu);
        populateContextMenuItems(*toHTMLMenuElement(nextElement), contextMenu);
        appendSeparator(contextMenu);
      } else if (!labelString.isEmpty()) {
        populateContextMenuItems(*toHTMLMenuElement(nextElement), subMenu);
        contextMenu.appendItem(
            ContextMenuItem(SubmenuType, ContextMenuItemCustomTagNoAction,
                            labelString, String(), &subMenu));
      }
      nextElement = Traversal<HTMLElement>::nextSibling(*nextElement);
    } else if (isHTMLMenuItemElement(*nextElement)) {
      appendMenuItem(toHTMLMenuItemElement(nextElement), contextMenu);
      if (ContextMenuItemBaseCustomTag + m_menuItems.size() >=
          ContextMenuItemLastCustomTag)
        break;
      nextElement = Traversal<HTMLElement>::next(*nextElement, &menu);
    } else {
      nextElement = Traversal<HTMLElement>::next(*nextElement, &menu);
    }
  }

  // Remove separators at the end of the menu and any submenus.
  while (contextMenu.items().size() &&
         contextMenu.items().last().type() == SeparatorType)
    contextMenu.removeLastItem();
}

HTMLElement* CustomContextMenuProvider::menuItemAt(unsigned menuId) {
  int itemIndex = menuId - ContextMenuItemBaseCustomTag;
  if (itemIndex < 0 ||
      static_cast<unsigned long>(itemIndex) >= m_menuItems.size())
    return nullptr;
  return m_menuItems[itemIndex].get();
}

}  // namespace blink