third_party/WebKit/Source/core/dom/DocumentStyleSheetCollection.cpp

/*
 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
 *           (C) 2001 Dirk Mueller (mueller@kde.org)
 *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
 * Copyright (C) 2013 Google Inc. All rights reserved.
 *
 * 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 "core/dom/DocumentStyleSheetCollection.h"

#include "core/css/resolver/StyleResolver.h"
#include "core/dom/Document.h"
#include "core/dom/DocumentStyleSheetCollector.h"
#include "core/dom/ProcessingInstruction.h"
#include "core/dom/StyleChangeReason.h"
#include "core/dom/StyleEngine.h"
#include "core/dom/StyleSheetCandidate.h"
#include "platform/RuntimeEnabledFeatures.h"

namespace blink {

DocumentStyleSheetCollection::DocumentStyleSheetCollection(TreeScope& treeScope)
    : TreeScopeStyleSheetCollection(treeScope)
{
    ASSERT(treeScope.rootNode() == treeScope.rootNode().document());
}

void DocumentStyleSheetCollection::collectStyleSheetsFromCandidates(StyleEngine& engine, DocumentStyleSheetCollector& collector)
{
    for (Node* n : m_styleSheetCandidateNodes) {
        StyleSheetCandidate candidate(*n);

        ASSERT(!candidate.isXSL());
        if (candidate.isImport()) {
            Document* document = candidate.importedDocument();
            if (!document)
                continue;
            if (collector.hasVisited(document))
                continue;
            collector.willVisit(document);
            document->styleEngine().updateStyleSheetsInImport(collector);
            continue;
        }

        if (candidate.isEnabledAndLoading()) {
            // it is loading but we should still decide which style sheet set to use
            if (candidate.hasPreferrableName())
                engine.setPreferredStylesheetSetNameIfNotSet(candidate.title());
            continue;
        }

        StyleSheet* sheet = candidate.sheet();
        if (!sheet)
            continue;

        if (candidate.hasPreferrableName())
            engine.setPreferredStylesheetSetNameIfNotSet(candidate.title());
        collector.appendSheetForList(sheet);
        if (candidate.canBeActivated(engine.preferredStylesheetSetName()))
            collector.appendActiveStyleSheet(toCSSStyleSheet(sheet));
    }
}

void DocumentStyleSheetCollection::collectStyleSheets(StyleEngine& engine, DocumentStyleSheetCollector& collector)
{
    ASSERT(&document().styleEngine() == &engine);
    collector.appendActiveStyleSheets(engine.injectedAuthorStyleSheets());
    collectStyleSheetsFromCandidates(engine, collector);
}

void DocumentStyleSheetCollection::updateActiveStyleSheets(StyleEngine& engine, StyleResolverUpdateMode updateMode)
{
    StyleSheetCollection collection;
    ActiveDocumentStyleSheetCollector collector(collection);
    collectStyleSheets(engine, collector);

    StyleSheetChange change;
    analyzeStyleSheetChange(updateMode, collection, change);

    if (change.styleResolverUpdateType == Reconstruct) {
        engine.clearMasterResolver();
        // TODO(rune@opera.com): The following depends on whether StyleRuleFontFace was modified or not.
        // We should only remove modified/removed @font-face rules, or @font-face rules from removed
        // stylesheets. We currently avoid clearing the font cache when we have had an analyzed update
        // and no @font-face rules were removed, in which case requiresFullStyleRecalc will be false.
        if (change.requiresFullStyleRecalc)
            engine.clearFontCache();
    } else if (StyleResolver* styleResolver = engine.resolver()) {
        if (change.styleResolverUpdateType != Additive) {
            ASSERT(change.styleResolverUpdateType == Reset);
            styleResolver->resetAuthorStyle(treeScope());
            engine.removeFontFaceRules(change.fontFaceRulesToRemove);
            styleResolver->removePendingAuthorStyleSheets(m_activeAuthorStyleSheets);
            styleResolver->lazyAppendAuthorStyleSheets(0, collection.activeAuthorStyleSheets());
        } else {
            styleResolver->lazyAppendAuthorStyleSheets(m_activeAuthorStyleSheets.size(), collection.activeAuthorStyleSheets());
        }
    }
    if (change.requiresFullStyleRecalc)
        document().setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::ActiveStylesheetsUpdate));

    collection.swap(*this);
}

} // namespace blink