root/Source/core/html/HTMLStyleElement.cpp

DEFINITIONS

1. styleLoadEventSender
2. m_scopedStyleRegistrationState
3. create
4. parseAttribute
5. scopedAttributeChanged
6. finishParsingChildren
7. registerWithScopingNode
8. unregisterWithScopingNode
9. insertedInto
10. removedFrom
11. didNotifySubtreeInsertionsToDocument
12. childrenChanged
13. media
14. type
15. scoped
16. setScoped
17. scopingNode
18. dispatchPendingLoadEvents
19. dispatchPendingEvent
20. notifyLoadedSheetAndAllCriticalSubresources
21. disabled
22. setDisabled

/*
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 *           (C) 2001 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2003, 2010 Apple Inc. All rights reserved.
 *           (C) 2007 Rob Buis (buis@kde.org)
 *
 * 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.
 */

#include "config.h"
#include "core/html/HTMLStyleElement.h"

#include "HTMLNames.h"
#include "core/css/MediaList.h"
#include "core/css/StyleSheetContents.h"
#include "core/dom/ContextFeatures.h"
#include "core/dom/Document.h"
#include "core/events/Event.h"
#include "core/events/EventSender.h"
#include "core/dom/StyleEngine.h"
#include "core/dom/shadow/ShadowRoot.h"

namespace WebCore {

using namespace HTMLNames;

static StyleEventSender& styleLoadEventSender()
{
    DEFINE_STATIC_LOCAL(StyleEventSender, sharedLoadEventSender, (EventTypeNames::load));
    return sharedLoadEventSender;
}

inline HTMLStyleElement::HTMLStyleElement(Document& document, bool createdByParser)
    : HTMLElement(styleTag, document)
    , StyleElement(&document, createdByParser)
    , m_firedLoad(false)
    , m_loadedSheet(false)
    , m_scopedStyleRegistrationState(NotRegistered)
{
    ScriptWrappable::init(this);
}

HTMLStyleElement::~HTMLStyleElement()
{
    // During tear-down, willRemove isn't called, so m_scopedStyleRegistrationState may still be RegisteredAsScoped or RegisteredInShadowRoot here.
    // Therefore we can't ASSERT(m_scopedStyleRegistrationState == NotRegistered).
    StyleElement::clearDocumentData(document(), this);

    styleLoadEventSender().cancelEvent(this);
}

PassRefPtr<HTMLStyleElement> HTMLStyleElement::create(Document& document, bool createdByParser)
{
    return adoptRef(new HTMLStyleElement(document, createdByParser));
}

void HTMLStyleElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
{
    if (name == titleAttr && m_sheet) {
        m_sheet->setTitle(value);
    } else if (name == scopedAttr && ContextFeatures::styleScopedEnabled(&document())) {
        scopedAttributeChanged(!value.isNull());
    } else if (name == mediaAttr && inDocument() && document().isActive() && m_sheet) {
        m_sheet->setMediaQueries(MediaQuerySet::create(value));
        document().modifiedStyleSheet(m_sheet.get(), RecalcStyleDeferred);
    } else {
        HTMLElement::parseAttribute(name, value);
    }
}

void HTMLStyleElement::scopedAttributeChanged(bool scoped)
{
    ASSERT(ContextFeatures::styleScopedEnabled(&document()));

    if (!inDocument())
        return;

    if (scoped) {
        if (m_scopedStyleRegistrationState == RegisteredAsScoped)
            return;

        // As any <style> in a shadow tree is treated as "scoped",
        // need to remove the <style> from its shadow root.
        ContainerNode* scopingNode = 0;
        if (m_scopedStyleRegistrationState == RegisteredInShadowRoot) {
            scopingNode = containingShadowRoot();
            unregisterWithScopingNode(scopingNode);
        }
        document().styleEngine()->removeStyleSheetCandidateNode(this, scopingNode, treeScope());
        registerWithScopingNode(true);

        document().styleEngine()->addStyleSheetCandidateNode(this, false);
        document().modifiedStyleSheet(sheet());
        return;
    }

    // If the <style> was scoped, need to remove the <style> from the scoping
    // element, i.e. the parent node.
    if (m_scopedStyleRegistrationState != RegisteredAsScoped)
        return;

    unregisterWithScopingNode(parentNode());
    document().styleEngine()->removeStyleSheetCandidateNode(this, parentNode(), treeScope());

    // As any <style> in a shadow tree is treated as "scoped",
    // need to add the <style> to its shadow root.
    if (isInShadowTree())
        registerWithScopingNode(false);

    document().styleEngine()->addStyleSheetCandidateNode(this, false);
    // FIXME: currently need to use FullStyleUpdate here.
    // Because ShadowTreeStyleSheetCollection doesn't know old scoping node.
    // So setNeedsStyleRecalc for old scoping node is not invoked.
    document().modifiedStyleSheet(sheet());
}

void HTMLStyleElement::finishParsingChildren()
{
    StyleElement::finishParsingChildren(this);
    HTMLElement::finishParsingChildren();
}

void HTMLStyleElement::registerWithScopingNode(bool scoped)
{
    // Note: We cannot rely on the 'scoped' element already being present when this method is invoked.
    // Therefore we cannot rely on scoped()!
    ASSERT(m_scopedStyleRegistrationState == NotRegistered);
    ASSERT(inDocument());
    if (m_scopedStyleRegistrationState != NotRegistered)
        return;

    ContainerNode* scope = scoped ? parentNode() : containingShadowRoot();
    if (!scope)
        return;
    if (!scope->isElementNode() && !scope->isShadowRoot()) {
        // DocumentFragment nodes should never be inDocument,
        // <style> should not be a child of Document, PI or some such.
        ASSERT_NOT_REACHED();
        return;
    }
    scope->registerScopedHTMLStyleChild();
    m_scopedStyleRegistrationState = scoped ? RegisteredAsScoped : RegisteredInShadowRoot;
}

void HTMLStyleElement::unregisterWithScopingNode(ContainerNode* scope)
{
    ASSERT(m_scopedStyleRegistrationState != NotRegistered || !ContextFeatures::styleScopedEnabled(&document()));
    if (!isRegisteredAsScoped())
        return;

    ASSERT(scope);
    if (scope) {
        ASSERT(scope->hasScopedHTMLStyleChild());
        scope->unregisterScopedHTMLStyleChild();
    }

    m_scopedStyleRegistrationState = NotRegistered;
}

Node::InsertionNotificationRequest HTMLStyleElement::insertedInto(ContainerNode* insertionPoint)
{
    HTMLElement::insertedInto(insertionPoint);
    if (insertionPoint->inDocument()) {
        if (m_scopedStyleRegistrationState == NotRegistered && (scoped() || isInShadowTree()))
            registerWithScopingNode(scoped());
    }
    return InsertionShouldCallDidNotifySubtreeInsertions;
}

void HTMLStyleElement::removedFrom(ContainerNode* insertionPoint)
{
    HTMLElement::removedFrom(insertionPoint);

    // In the current implementation, <style scoped> is only registered if the node is in the document.
    // That is, because willRemove() is also called if an ancestor is removed from the document.
    // Now, if we want to register <style scoped> even if it's not inDocument,
    // we'd need to find a way to discern whether that is the case, or whether <style scoped> itself is about to be removed.
    ContainerNode* scopingNode = 0;
    if (m_scopedStyleRegistrationState != NotRegistered) {
        if (m_scopedStyleRegistrationState == RegisteredInShadowRoot) {
            scopingNode = containingShadowRoot();
            if (!scopingNode)
                scopingNode = insertionPoint->containingShadowRoot();
        } else {
            scopingNode = parentNode() ? parentNode() : insertionPoint;
        }

        unregisterWithScopingNode(scopingNode);
    }

    if (insertionPoint->inDocument()) {
        TreeScope* containingScope = containingShadowRoot();
        StyleElement::removedFromDocument(document(), this, scopingNode, containingScope ? *containingScope : insertionPoint->treeScope());
    }
}

void HTMLStyleElement::didNotifySubtreeInsertionsToDocument()
{
    StyleElement::processStyleSheet(document(), this);
}

void HTMLStyleElement::childrenChanged(bool changedByParser, Node* beforeChange, Node* afterChange, int childCountDelta)
{
    HTMLElement::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);
    StyleElement::childrenChanged(this);
}

const AtomicString& HTMLStyleElement::media() const
{
    return getAttribute(mediaAttr);
}

const AtomicString& HTMLStyleElement::type() const
{
    return getAttribute(typeAttr);
}

bool HTMLStyleElement::scoped() const
{
    return fastHasAttribute(scopedAttr) && ContextFeatures::styleScopedEnabled(&document());
}

void HTMLStyleElement::setScoped(bool scopedValue)
{
    setBooleanAttribute(scopedAttr, scopedValue);
}

ContainerNode* HTMLStyleElement::scopingNode()
{
    if (!inDocument())
        return 0;

    if (!isRegisteredAsScoped())
        return &document();

    if (isRegisteredInShadowRoot())
        return containingShadowRoot();

    return parentNode();
}

void HTMLStyleElement::dispatchPendingLoadEvents()
{
    styleLoadEventSender().dispatchPendingEvents();
}

void HTMLStyleElement::dispatchPendingEvent(StyleEventSender* eventSender)
{
    ASSERT_UNUSED(eventSender, eventSender == &styleLoadEventSender());
    dispatchEvent(Event::create(m_loadedSheet ? EventTypeNames::load : EventTypeNames::error));
}

void HTMLStyleElement::notifyLoadedSheetAndAllCriticalSubresources(bool errorOccurred)
{
    if (m_firedLoad)
        return;
    m_loadedSheet = !errorOccurred;
    styleLoadEventSender().dispatchEventSoon(this);
    m_firedLoad = true;
}

bool HTMLStyleElement::disabled() const
{
    if (!m_sheet)
        return false;

    return m_sheet->disabled();
}

void HTMLStyleElement::setDisabled(bool setDisabled)
{
    if (CSSStyleSheet* styleSheet = sheet())
        styleSheet->setDisabled(setDisabled);
}

}