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#include "FastPreprocessor.h"

#include <cplusplus/Literals.h>
#include <cplusplus/TranslationUnit.h>

#include <QDir>

using namespace CPlusPlus;

FastPreprocessor::FastPreprocessor(const Snapshot &snapshot)
    : _snapshot(snapshot)
    , _preproc(this, &_env)
{ }

// This is a temporary fix to handle non-ascii characters. This can be removed when the lexer can
// handle multi-byte characters.
static QByteArray convertToLatin1(const QByteArray &contents)
{
    const char *p = contents.constData();
    while (char ch = *p++)
        if (ch & 0x80)
            return QString::fromUtf8(contents).toLatin1();

    return contents;
}

QByteArray FastPreprocessor::run(Document::Ptr newDoc, const QByteArray &source)
{
    std::swap(newDoc, _currentDoc);
    const QString fileName = _currentDoc->fileName();
    _preproc.setExpandFunctionlikeMacros(false);
    _preproc.setKeepComments(true);

    if (Document::Ptr doc = _snapshot.document(fileName)) {
        _merged.insert(fileName);

        for (Snapshot::const_iterator i = _snapshot.begin(), ei = _snapshot.end(); i != ei; ++i) {
            if (isInjectedFile(i.key()))
                mergeEnvironment(i.key());
        }

        foreach (const Document::Include &i, doc->resolvedIncludes())
            mergeEnvironment(i.resolvedFileName());
    }

    QByteArray src = convertToLatin1(source);

    const QByteArray preprocessed = _preproc.run(fileName, src);
//    qDebug("FastPreprocessor::run for %s produced [[%s]]", fileName.toUtf8().constData(), preprocessed.constData());
    std::swap(newDoc, _currentDoc);
    return preprocessed;
}

void FastPreprocessor::sourceNeeded(unsigned line, const QString &fileName,
                                    IncludeType mode)
{
    Q_ASSERT(_currentDoc);
    // CHECKME: Is that cleanName needed?
    QString cleanName = QDir::cleanPath(fileName);
    _currentDoc->addIncludeFile(Document::Include(fileName, cleanName, line, mode));
    mergeEnvironment(fileName);
}

void FastPreprocessor::mergeEnvironment(const QString &fileName)
{
    if (! _merged.contains(fileName)) {
        _merged.insert(fileName);

        if (Document::Ptr doc = _snapshot.document(fileName)) {
            foreach (const Document::Include &i, doc->resolvedIncludes())
                mergeEnvironment(i.resolvedFileName());

            _env.addMacros(doc->definedMacros());
        }
    }
}

void FastPreprocessor::macroAdded(const Macro &macro)
{
    Q_ASSERT(_currentDoc);

    _currentDoc->appendMacro(macro);
}

static const Macro revision(const Snapshot &s, const Macro &m)
{
    if (Document::Ptr d = s.document(m.fileName())) {
        Macro newMacro(m);
        newMacro.setFileRevision(d->revision());
        return newMacro;
    }

    return m;
}

void FastPreprocessor::passedMacroDefinitionCheck(unsigned offset, unsigned line, const Macro &macro)
{
    Q_ASSERT(_currentDoc);

    _currentDoc->addMacroUse(revision(_snapshot, macro),
                             offset, macro.name().length(), line,
                             QVector<MacroArgumentReference>());
}

void FastPreprocessor::failedMacroDefinitionCheck(unsigned offset, const ByteArrayRef &name)
{
    Q_ASSERT(_currentDoc);

    _currentDoc->addUndefinedMacroUse(QByteArray(name.start(), name.size()), offset);
}

void FastPreprocessor::notifyMacroReference(unsigned offset, unsigned line, const Macro &macro)
{
    Q_ASSERT(_currentDoc);

    _currentDoc->addMacroUse(revision(_snapshot, macro),
                             offset, macro.name().length(), line,
                             QVector<MacroArgumentReference>());
}

void FastPreprocessor::startExpandingMacro(unsigned offset, unsigned line,
                                          const Macro &macro,
                                          const QVector<MacroArgumentReference> &actuals)
{
    Q_ASSERT(_currentDoc);

    _currentDoc->addMacroUse(revision(_snapshot, macro),
                             offset, macro.name().length(), line, actuals);
}