Source/WebCore/css/parser/CSSParserImpl.h

// Copyright 2014 The Chromium Authors. All rights reserved.
// Copyright (C) 2016-2021 Apple Inc. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//    * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//    * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#pragma once

#include "CSSDeferredParser.h"
#include "CSSParser.h"
#include "CSSParserTokenRange.h"
#include "CSSPropertyNames.h"
#include "StyleRule.h"

#include <memory>
#include <wtf/Vector.h>
#include <wtf/text/WTFString.h>

namespace WebCore {

class CSSParserObserver;
class CSSParserObserverWrapper;
class CSSSelectorList;
class CSSTokenizer;
class StyleRuleCounterStyle;
class StyleRuleKeyframe;
class StyleRule;
class StyleRuleBase;
class StyleRuleCharset;
class StyleRuleFontFace;
class StyleRuleFontPaletteValues;
class StyleRuleImport;
class StyleRuleKeyframes;
class StyleRuleLayer;
class StyleRuleMedia;
class StyleRuleNamespace;
class StyleRulePage;
class StyleRuleSupports;
class StyleRuleViewport;
class StyleSheetContents;
class ImmutableStyleProperties;
class Element;
class MutableStyleProperties;
    
class CSSParserImpl {
    WTF_MAKE_NONCOPYABLE(CSSParserImpl);
public:
    CSSParserImpl(const CSSParserContext&, const String&, StyleSheetContents* = nullptr, CSSParserObserverWrapper* = nullptr, CSSParser::RuleParsing = CSSParser::RuleParsing::Normal);

    enum AllowedRulesType {
        // As per css-syntax, css-cascade and css-namespaces, @charset rules
        // must come first, followed by @import then @namespace.
        // AllowImportRules actually means we allow @import and any rules thay
        // may follow it, i.e. @namespace rules and regular rules.
        // AllowCharsetRules and AllowNamespaceRules behave similarly.
        AllowCharsetRules,
        AllowLayerStatementRules,
        AllowImportRules,
        AllowNamespaceRules,
        RegularRules,
        KeyframeRules,
        ApplyRules, // For @apply inside style rules
        CounterStyleRules,
        NoRules, // For parsing at-rules inside declaration lists
    };

    static CSSParser::ParseResult parseValue(MutableStyleProperties*, CSSPropertyID, const String&, bool important, const CSSParserContext&);
    static CSSParser::ParseResult parseCustomPropertyValue(MutableStyleProperties*, const AtomString& propertyName, const String&, bool important, const CSSParserContext&);
    static Ref<ImmutableStyleProperties> parseInlineStyleDeclaration(const String&, const Element*);
    static bool parseDeclarationList(MutableStyleProperties*, const String&, const CSSParserContext&);
    static RefPtr<StyleRuleBase> parseRule(const String&, const CSSParserContext&, StyleSheetContents*, AllowedRulesType);
    static void parseStyleSheet(const String&, const CSSParserContext&, StyleSheetContents&, CSSParser::RuleParsing);
    static CSSSelectorList parsePageSelector(CSSParserTokenRange, StyleSheetContents*);

    static Vector<double> parseKeyframeKeyList(const String&);

    bool supportsDeclaration(CSSParserTokenRange&);
    const CSSParserContext& context() const { return m_context; }

    static void parseDeclarationListForInspector(const String&, const CSSParserContext&, CSSParserObserver&);
    static void parseStyleSheetForInspector(const String&, const CSSParserContext&, StyleSheetContents*, CSSParserObserver&);

    static Ref<ImmutableStyleProperties> parseDeferredDeclaration(CSSParserTokenRange, const CSSParserContext&, StyleSheetContents*);
    static void parseDeferredRuleList(CSSParserTokenRange, CSSDeferredParser&, Vector<RefPtr<StyleRuleBase>>&);
    static void parseDeferredKeyframeList(CSSParserTokenRange, CSSDeferredParser&, StyleRuleKeyframes&);

    CSSTokenizer* tokenizer() const { return m_tokenizer.get(); };
    CSSDeferredParser* deferredParser() const { return m_deferredParser.get(); }

private:
    CSSParserImpl(const CSSParserContext&, StyleSheetContents*);
    CSSParserImpl(CSSDeferredParser&);

    enum RuleListType {
        TopLevelRuleList,
        RegularRuleList,
        KeyframesRuleList
    };

    // Returns whether the first encountered rule was valid
    template<typename T>
    bool consumeRuleList(CSSParserTokenRange, RuleListType, T callback);

    // These two functions update the range they're given
    RefPtr<StyleRuleBase> consumeAtRule(CSSParserTokenRange&, AllowedRulesType);
    RefPtr<StyleRuleBase> consumeQualifiedRule(CSSParserTokenRange&, AllowedRulesType);

    static RefPtr<StyleRuleCharset> consumeCharsetRule(CSSParserTokenRange prelude);
    RefPtr<StyleRuleImport> consumeImportRule(CSSParserTokenRange prelude);
    RefPtr<StyleRuleNamespace> consumeNamespaceRule(CSSParserTokenRange prelude);
    RefPtr<StyleRuleMedia> consumeMediaRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleSupports> consumeSupportsRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleViewport> consumeViewportRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleFontFace> consumeFontFaceRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleFontPaletteValues> consumeFontPaletteValuesRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleKeyframes> consumeKeyframesRule(bool webkitPrefixed, CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRulePage> consumePageRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleCounterStyle> consumeCounterStyleRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRuleLayer> consumeLayerRule(CSSParserTokenRange prelude, std::optional<CSSParserTokenRange> block);
    RefPtr<StyleRuleContainer> consumeContainerRule(CSSParserTokenRange prelude, CSSParserTokenRange block);

    RefPtr<StyleRuleKeyframe> consumeKeyframeStyleRule(CSSParserTokenRange prelude, CSSParserTokenRange block);
    RefPtr<StyleRule> consumeStyleRule(CSSParserTokenRange prelude, CSSParserTokenRange block);

    void consumeDeclarationList(CSSParserTokenRange, StyleRuleType);
    void consumeDeclaration(CSSParserTokenRange, StyleRuleType);
    void consumeDeclarationValue(CSSParserTokenRange, CSSPropertyID, bool important, StyleRuleType);
    void consumeCustomPropertyValue(CSSParserTokenRange, const AtomString& propertyName, bool important);

    static Vector<double> consumeKeyframeKeyList(CSSParserTokenRange);

    Ref<DeferredStyleProperties> createDeferredStyleProperties(const CSSParserTokenRange& propertyRange);
    
    void adoptTokenizerEscapedStrings();

    // FIXME: Can we build StylePropertySets directly?
    // FIXME: Investigate using a smaller inline buffer
    ParsedPropertyVector m_parsedProperties;
    const CSSParserContext& m_context;

    RefPtr<StyleSheetContents> m_styleSheet;

    // For deferred property parsing.
    RefPtr<CSSDeferredParser> m_deferredParser;
    
    // For normal parsing.
    std::unique_ptr<CSSTokenizer> m_tokenizer;

    // For the inspector
    CSSParserObserverWrapper* m_observerWrapper { nullptr };
};

} // namespace WebCore