MediaQueryParser.h   [plain text]

// Copyright 2014 The Chromium Authors. All rights reserved.
// Copyright (C) 2016 Apple Inc. All rights reserved.
//
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#pragma once

#include "CSSParserToken.h"
#include "CSSParserTokenRange.h"
#include "MediaQuery.h"
#include "MediaQueryBlockWatcher.h"
#include "MediaQueryExpression.h"
#include "MediaQueryParserContext.h"
#include <wtf/Optional.h>
#include <wtf/text/WTFString.h>

namespace WebCore {

class MediaQuerySet;
struct CSSParserContext;

class MediaQueryParser {
    WTF_MAKE_NONCOPYABLE(MediaQueryParser);
public:
    static RefPtr<MediaQuerySet> parseMediaQuerySet(const String&, MediaQueryParserContext);
    static RefPtr<MediaQuerySet> parseMediaQuerySet(CSSParserTokenRange, MediaQueryParserContext);
    static RefPtr<MediaQuerySet> parseMediaCondition(CSSParserTokenRange, MediaQueryParserContext);

private:
    enum ParserType {
        MediaQuerySetParser,
        MediaConditionParser,
    };

    MediaQueryParser(ParserType, MediaQueryParserContext);
    virtual ~MediaQueryParser();

    RefPtr<MediaQuerySet> parseInternal(CSSParserTokenRange);

    void processToken(const CSSParserToken&, CSSParserTokenRange&);

    void readRestrictor(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readMediaNot(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readMediaType(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readAnd(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readFeatureStart(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readFeature(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readFeatureColon(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readFeatureValue(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void readFeatureEnd(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void skipUntilComma(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void skipUntilBlockEnd(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);
    void done(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);

    using State = void (MediaQueryParser::*)(CSSParserTokenType, const CSSParserToken&, CSSParserTokenRange&);

    void setStateAndRestrict(State, MediaQuery::Restrictor);
    void handleBlocks(const CSSParserToken&);
    
    void commitMediaQuery();

    class MediaQueryData {
        WTF_MAKE_NONCOPYABLE(MediaQueryData);
    public:
        explicit MediaQueryData(MediaQueryParserContext);
        void clear();
        void addExpression(CSSParserTokenRange&);
        bool lastExpressionValid();
        void removeLastExpression();
        void setMediaType(const String& mediaType) { m_mediaType = mediaType; }

        MediaQuery::Restrictor restrictor() const { return m_restrictor; }
        Vector<MediaQueryExpression>& expressions() { return m_expressions; }
        const Optional<String>& mediaType() const { return m_mediaType; }

        bool currentMediaQueryChanged() const
        {
            return (m_restrictor != MediaQuery::None || m_mediaType || !m_expressions.isEmpty());
        }
        MediaQuery::Restrictor restrictor() { return m_restrictor; }

        void setRestrictor(MediaQuery::Restrictor restrictor) { m_restrictor = restrictor; }

        void setMediaFeature(const String& str) { m_mediaFeature = str; }

        void setMediaQueryParserContext(MediaQueryParserContext context) { m_context = context; }

    private:
        MediaQuery::Restrictor m_restrictor { MediaQuery::None };
        Optional<String> m_mediaType;
        Vector<MediaQueryExpression> m_expressions;
        String m_mediaFeature;
        MediaQueryParserContext m_context;
    };

    State m_state;
    ParserType m_parserType;
    MediaQueryData m_mediaQueryData;
    RefPtr<MediaQuerySet> m_querySet;
    MediaQueryBlockWatcher m_blockWatcher;

    const static State ReadRestrictor;
    const static State ReadMediaNot;
    const static State ReadMediaType;
    const static State ReadAnd;
    const static State ReadFeatureStart;
    const static State ReadFeature;
    const static State ReadFeatureColon;
    const static State ReadFeatureValue;
    const static State ReadFeatureEnd;
    const static State SkipUntilComma;
    const static State SkipUntilBlockEnd;
    const static State Done;
};

} // namespace WebCore