qcssparser.cpp

奇趣公司比较新的qt/emd版本

    return result;
}

Parser::Parser(QString css, bool isFile)
{
    if (isFile) {
        QFile file(css);
        if (file.open(QFile::ReadOnly)) {
            sourcePath = QFileInfo(css).absolutePath() + QLatin1String("/");
            QTextStream stream(&file);
            css = stream.readAll();
        } else {
            qWarning() << "QCss::Parser - Failed to load file " << css;
            css.clear();
        }
    }
    init(css);
}

Parser::Parser()
{
    index = 0;
    errorIndex = -1;
    hasEscapeSequences = false;
}

void Parser::init(const QString &css)
{
    symbols.resize(0);
    Scanner::scan(Scanner::preprocess(css, &hasEscapeSequences), &symbols);
    index = 0;
    errorIndex = -1;
    symbols.reserve(qMax(symbols.capacity(), symbols.size()));
}

bool Parser::parse(StyleSheet *styleSheet)
{
    if (testTokenAndEndsWith(ATKEYWORD_SYM, QLatin1String("charset"))) {
        if (!next(STRING)) return false;
        if (!next(SEMICOLON)) return false;
    }

    while (test(S) || test(CDO) || test(CDC));

    while (testImport()) {
        ImportRule rule;
        if (!parseImport(&rule)) return false;
        styleSheet->importRules.append(rule);
        while (test(S) || test(CDO) || test(CDC));
    }

    do {
        if (testMedia()) {
            MediaRule rule;
            if (!parseMedia(&rule)) return false;
            styleSheet->mediaRules.append(rule);
        } else if (testPage()) {
            PageRule rule;
            if (!parsePage(&rule)) return false;
            styleSheet->pageRules.append(rule);
        } else if (testRuleset()) {
            StyleRule rule;
            if (!parseRuleset(&rule)) return false;
            styleSheet->styleRules.append(rule);
        } else if (test(ATKEYWORD_SYM)) {
            if (!until(RBRACE)) return false;
        } else if (hasNext()) {
            return false;
        }
        while (test(S) || test(CDO) || test(CDC));
    } while (hasNext());
    return true;
}

Symbol Parser::errorSymbol()
{
    if (errorIndex == -1) return Symbol();
    return symbols.at(errorIndex);
}

static inline void removeOptionalQuotes(QString *str)
{
    if (!str->startsWith(QLatin1Char('\''))
        && !str->startsWith(QLatin1Char('\"')))
        return;
    str->remove(0, 1);
    str->chop(1);
}

bool Parser::parseImport(ImportRule *importRule)
{
    skipSpace();

    if (test(STRING)) {
        importRule->href = lexem();
    } else {
        if (!testAndParseUri(&importRule->href)) return false;
    }
    removeOptionalQuotes(&importRule->href);

    skipSpace();

    if (testMedium()) {
        if (!parseMedium(&importRule->media)) return false;

        while (test(COMMA)) {
            skipSpace();
            if (!parseNextMedium(&importRule->media)) return false;
        }
    }

    if (!next(SEMICOLON)) return false;

    skipSpace();
    return true;
}

bool Parser::parseMedia(MediaRule *mediaRule)
{
    do {
        skipSpace();
        if (!parseNextMedium(&mediaRule->media)) return false;
    } while (test(COMMA));

    if (!next(LBRACE)) return false;
    skipSpace();

    while (testRuleset()) {
        StyleRule rule;
        if (!parseRuleset(&rule)) return false;
        mediaRule->styleRules.append(rule);
    }

    if (!next(RBRACE)) return false;
    skipSpace();
    return true;
}

bool Parser::parseMedium(QStringList *media)
{
    media->append(lexem());
    skipSpace();
    return true;
}

bool Parser::parsePage(PageRule *pageRule)
{
    skipSpace();

    if (testPseudoPage())
        if (!parsePseudoPage(&pageRule->selector)) return false;

    skipSpace();
    if (!next(LBRACE)) return false;

    do {
        skipSpace();
        Declaration decl;
        if (!parseNextDeclaration(&decl)) return false;
        if (!decl.isEmpty())
            pageRule->declarations.append(decl);
    } while (test(SEMICOLON));

    if (!next(RBRACE)) return false;
    skipSpace();
    return true;
}

bool Parser::parsePseudoPage(QString *selector)
{
    if (!next(IDENT)) return false;
    *selector = lexem();
    return true;
}

bool Parser::parseNextOperator(Value *value)
{
    if (!hasNext()) return true;
    switch (next()) {
        case SLASH: value->type = Value::TermOperatorSlash; skipSpace(); break;
        case COMMA: value->type = Value::TermOperatorComma; skipSpace(); break;
        default: prev(); break;
    }
    return true;
}

bool Parser::parseCombinator(BasicSelector::Relation *relation)
{
    *relation = BasicSelector::NoRelation;
    if (lookup() == S) {
        *relation = BasicSelector::MatchNextSelectorIfAncestor;
        skipSpace();
    } else {
        prev();
    }
    if (test(PLUS)) {
        *relation = BasicSelector::MatchNextSelectorIfPreceeds;
    } else if (test(GREATER)) {
        *relation = BasicSelector::MatchNextSelectorIfParent;
    }
    skipSpace();
    return true;
}

bool Parser::parseProperty(Declaration *decl)
{
    decl->property = lexem();
    decl->propertyId = static_cast<Property>(findKnownValue(decl->property, properties, NumProperties));
    skipSpace();
    return true;
}

bool Parser::parseRuleset(StyleRule *styleRule)
{
    Selector sel;
    if (!parseSelector(&sel)) return false;
    styleRule->selectors.append(sel);

    while (test(COMMA)) {
        skipSpace();
        Selector sel;
        if (!parseNextSelector(&sel)) return false;
        styleRule->selectors.append(sel);
    }

    skipSpace();
    if (!next(LBRACE)) return false;
    const int declarationStart = index;

    do {
        skipSpace();
        Declaration decl;
        const int rewind = index;
        if (!parseNextDeclaration(&decl)) {
            index = rewind;
            const bool foundSemicolon = until(SEMICOLON);
            const int semicolonIndex = index;

            index = declarationStart;
            const bool foundRBrace = until(RBRACE);

            if (foundSemicolon && semicolonIndex < index) {
                decl = Declaration();
                index = semicolonIndex - 1;
            } else {
                skipSpace();
                return foundRBrace;
            }
        }
        if (!decl.isEmpty())
            styleRule->declarations.append(decl);
    } while (test(SEMICOLON));

    if (!next(RBRACE)) return false;
    skipSpace();
    return true;
}

bool Parser::parseSelector(Selector *sel)
{
    BasicSelector basicSel;
    if (!parseSimpleSelector(&basicSel)) return false;
    while (testCombinator()) {
        if (!parseCombinator(&basicSel.relationToNext)) return false;

        if (!testSimpleSelector()) break;
        sel->basicSelectors.append(basicSel);

        basicSel = BasicSelector();
        if (!parseSimpleSelector(&basicSel)) return false;
    }
    sel->basicSelectors.append(basicSel);
    return true;
}

bool Parser::parseSimpleSelector(BasicSelector *basicSel)
{
    int minCount = 0;
    if (lookupElementName()) {
        if (!parseElementName(&basicSel->elementName)) return false;
    } else {
        prev();
        minCount = 1;
    }
    bool onceMore;
    int count = 0;
    do {
        onceMore = false;
        if (test(HASH)) {
            QString id = lexem();
            // chop off leading #
            id.remove(0, 1);
            basicSel->ids.append(id);
            onceMore = true;
        } else if (testClass()) {
            onceMore = true;
            AttributeSelector a;
            a.name = QLatin1String("class");
            a.valueMatchCriterium = AttributeSelector::MatchContains;
            if (!parseClass(&a.value)) return false;
            basicSel->attributeSelectors.append(a);
        } else if (testAttrib()) {
            onceMore = true;
            AttributeSelector a;
            if (!parseAttrib(&a)) return false;
            basicSel->attributeSelectors.append(a);
        } else if (testPseudo()) {
            onceMore = true;
            Pseudo ps;
            if (!parsePseudo(&ps)) return false;
            basicSel->pseudos.append(ps);
        }
        if (onceMore) ++count;
    } while (onceMore);
    return count >= minCount;
}

bool Parser::parseClass(QString *name)
{
    if (!next(IDENT)) return false;
    *name = lexem();
    return true;
}

bool Parser::parseElementName(QString *name)
{
    switch (lookup()) {
        case STAR: name->clear(); break;
        case IDENT: *name = lexem(); break;
        default: return false;
    }
    return true;
}

bool Parser::parseAttrib(AttributeSelector *attr)
{
    skipSpace();
    if (!next(IDENT)) return false;
    attr->name = lexem();
    skipSpace();

    if (test(EQUAL)) {
        attr->valueMatchCriterium = AttributeSelector::MatchEqual;
    } else if (test(INCLUDES)) {
        attr->valueMatchCriterium = AttributeSelector::MatchContains;
    } else if (test(DASHMATCH)) {
        attr->valueMatchCriterium = AttributeSelector::MatchBeginsWith;
    } else {
        return next(RBRACKET);
    }

    skipSpace();

    if (!test(IDENT) && !test(STRING)) return false;
    attr->value = unquotedLexem();

    skipSpace();
    return next(RBRACKET);
}

bool Parser::parsePseudo(Pseudo *pseudo)
{
    test(COLON);
    pseudo->negated = test(EXCLAMATION_SYM);
    if (test(IDENT)) {
        pseudo->name = lexem();
        pseudo->type = static_cast<PseudoClass>(findKnownValue(pseudo->name, pseudos, NumPseudos));
        return true;
    }
    if (!next(FUNCTION)) return false;
    pseudo->function = lexem();
    // chop off trailing parenthesis
    pseudo->function.chop(1);
    skipSpace();
    if (!test(IDENT)) return false;
    pseudo->name = lexem();
    skipSpace();
    return next(RPAREN);
}

bool Parser::parseNextDeclaration(Declaration *decl)
{
    if (!testProperty())
        return true; // not an error!
    if (!parseProperty(decl)) return false;
    if (!next(COLON)) return false;
    skipSpace();
    if (!parseNextExpr(&decl->values)) return false;
    if (testPrio())
        if (!parsePrio(decl)) return false;
    return true;
}

bool Parser::testPrio()
{
    const int rewind = index;
    if (!test(EXCLAMATION_SYM)) return false;
    skipSpace();
    if (!test(IDENT)) {
        index = rewind;
        return false;
    }
    if (lexem().compare(QLatin1String("important"), Qt::CaseInsensitive) != 0) {
        index = rewind;
        return false;
    }
    return true;
}

bool Parser::parsePrio(Declaration *declaration)
{