Source/core/dom/CustomElementRegistrationContext.cpp

/*
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#include "config.h"
#include "core/dom/CustomElementRegistrationContext.h"

#include "HTMLNames.h"
#include "SVGNames.h"
#include "bindings/v8/ExceptionState.h"
#include "core/dom/CustomElement.h"
#include "core/dom/CustomElementDefinition.h"
#include "core/dom/Element.h"
#include "core/html/HTMLElement.h"
#include "core/html/HTMLUnknownElement.h"
#include "core/svg/SVGUnknownElement.h"
#include "wtf/RefPtr.h"

namespace WebCore {

void CustomElementRegistrationContext::registerElement(Document* document, CustomElementConstructorBuilder* constructorBuilder, const AtomicString& type, ExceptionState& es)
{
    CustomElementDefinition* definition = m_registry.registerElement(document, constructorBuilder, type, es);

    if (!definition)
        return;

    // Upgrade elements that were waiting for this definition.
    const CustomElementUpgradeCandidateMap::ElementSet& upgradeCandidates = m_candidates.takeUpgradeCandidatesFor(definition->descriptor());
    for (CustomElementUpgradeCandidateMap::ElementSet::const_iterator it = upgradeCandidates.begin(); it != upgradeCandidates.end(); ++it)
        didResolveElement(definition, *it);
}

PassRefPtr<Element> CustomElementRegistrationContext::createCustomTagElement(Document* document, const QualifiedName& tagName)
{
    ASSERT(CustomElement::isCustomTagName(tagName.localName()));

    if (!document)
        return 0;

    RefPtr<Element> element;

    if (HTMLNames::xhtmlNamespaceURI == tagName.namespaceURI()) {
        element = HTMLElement::create(tagName, document);
    } else if (SVGNames::svgNamespaceURI == tagName.namespaceURI()) {
        element = SVGUnknownElement::create(tagName, document);
    } else {
        // XML elements are not custom elements, so return early.
        return Element::create(tagName, document);
    }

    resolve(element.get(), nullAtom);
    return element.release();
}

void CustomElementRegistrationContext::didGiveTypeExtension(Element* element, const AtomicString& type)
{
    resolve(element, type);
}

void CustomElementRegistrationContext::resolve(Element* element, const AtomicString& typeExtension)
{
    // If an element has a custom tag name it takes precedence over
    // the "is" attribute (if any).
    const AtomicString& type = CustomElement::isCustomTagName(element->localName())
        ? element->localName()
        : typeExtension;
    ASSERT(!type.isNull());

    CustomElementDescriptor descriptor(type, element->namespaceURI(), element->localName());
    CustomElementDefinition* definition = m_registry.find(descriptor);
    if (definition)
        didResolveElement(definition, element);
    else
        didCreateUnresolvedElement(descriptor, element);
}

void CustomElementRegistrationContext::didResolveElement(CustomElementDefinition* definition, Element* element)
{
    CustomElement::define(element, definition);
}

void CustomElementRegistrationContext::didCreateUnresolvedElement(const CustomElementDescriptor& descriptor, Element* element)
{
    m_candidates.add(descriptor, element);
}

void CustomElementRegistrationContext::customElementWasDestroyed(Element* element)
{
    m_candidates.remove(element);
}

PassRefPtr<CustomElementRegistrationContext> CustomElementRegistrationContext::create()
{
    return adoptRef(new CustomElementRegistrationContext());
}

void CustomElementRegistrationContext::setIsAttributeAndTypeExtension(Element* element, const AtomicString& type)
{
    ASSERT(element);
    ASSERT(!type.isEmpty());
    element->setAttribute(HTMLNames::isAttr, type);
    setTypeExtension(element, type);
}

void CustomElementRegistrationContext::setTypeExtension(Element* element, const AtomicString& type)
{
    if (!element->isHTMLElement() && !element->isSVGElement())
        return;

    if (element->isCustomElement()) {
        // This can happen if:
        // 1. The element has a custom tag, which takes precedence over
        //    type extensions.
        // 2. Undoing a command (eg ReplaceNodeWithSpan) recycles an
        //    element but tries to overwrite its attribute list.
        return;
    }

    // Custom tags take precedence over type extensions
    ASSERT(!CustomElement::isCustomTagName(element->localName()));

    if (CustomElementRegistrationContext* context = element->document()->registrationContext())
        context->didGiveTypeExtension(element, type);
}

} // namespace WebCore