void XSLStyleSheet::loadChildSheet(const String& href)
{
    OwnPtr<XSLImportRule> childRule = XSLImportRule::create(this, href);
    XSLImportRule* c = childRule.get();
    m_children.append(childRule.release());
    c->loadSheet();
}

xmlDocPtr XSLStyleSheet::locateStylesheetSubResource(xmlDocPtr parentDoc, const xmlChar* uri)
{
    bool matchedParent = (parentDoc == document());
    for (unsigned i = 0; i < m_children.size(); ++i) {
        XSLImportRule* import = m_children.at(i).get();
        XSLStyleSheet* child = import->styleSheet();
        if (!child)
            continue;
        if (matchedParent) {
            if (child->processed())
                continue; // libxslt has been given this sheet already.

            // Check the URI of the child stylesheet against the doc URI.
            // In order to ensure that libxml canonicalized both URLs, we get the original href
            // string from the import rule and canonicalize it using libxml before comparing it
            // with the URI argument.
            CString importHref = import->href().utf8();
            xmlChar* base = xmlNodeGetBase(parentDoc, (xmlNodePtr)parentDoc);
            xmlChar* childURI = xmlBuildURI((const xmlChar*)importHref.data(), base);
            bool equalURIs = xmlStrEqual(uri, childURI);
            xmlFree(base);
            xmlFree(childURI);
            if (equalURIs) {
                child->markAsProcessed();
                return child->document();
            }
            continue;
        }
        xmlDocPtr result = import->styleSheet()->locateStylesheetSubResource(parentDoc, uri);
        if (result)
            return result;
    }

    return 0;
}

void XSLStyleSheet::loadChildSheet(const String& href)
{
    auto childRule = std::make_unique<XSLImportRule>(this, href);
    XSLImportRule* c = childRule.get();
    m_children.append(childRule.release());
    c->loadSheet();
}

void XSLStyleSheet::clearDocuments()
{
    m_stylesheetDoc = 0;
    for (unsigned i = 0; i < m_children.size(); ++i) {
        XSLImportRule* import = m_children.at(i).get();
        if (import->styleSheet())
            import->styleSheet()->clearDocuments();
    }
}

bool XSLStyleSheet::isLoading()
{
    unsigned len = length();
    for (unsigned i = 0; i < len; ++i) {
        StyleBase* rule = item(i);
        if (rule->isImportRule()) {
            XSLImportRule* import = static_cast<XSLImportRule*>(rule);
            if (import->isLoading())
                return true;
        }
    }
    return false;
}

void XSLStyleSheet::loadChildSheet(const String& href)
{
    XSLImportRule* childRule = XSLImportRule::create(this, href);
    m_children.append(childRule);
    childRule->loadSheet();
}