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#include "cpplocatorfilter.h"
#include "cppmodelmanager.h"

#include <texteditor/itexteditor.h>
#include <texteditor/basetexteditor.h>
#include <utils/fileutils.h>

#include <QStringMatcher>

using namespace CppTools::Internal;
using namespace Utils;

static const int MaxPendingDocuments = 10;

CppLocatorFilter::CppLocatorFilter(CppModelManager *manager)
    : m_manager(manager)
    , m_pendingDocumentsMutex(QMutex::Recursive)
{
    setId("Classes and Methods");
    setDisplayName(tr("C++ Classes and Methods"));
    setShortcutString(QString(QLatin1Char(':')));
    setIncludedByDefault(false);

    m_pendingDocuments.reserve(MaxPendingDocuments);

    connect(manager, SIGNAL(documentUpdated(CPlusPlus::Document::Ptr)),
            this, SLOT(onDocumentUpdated(CPlusPlus::Document::Ptr)));

    connect(manager, SIGNAL(aboutToRemoveFiles(QStringList)),
            this, SLOT(onAboutToRemoveFiles(QStringList)));
}

CppLocatorFilter::~CppLocatorFilter()
{ }


void CppLocatorFilter::flushPendingDocument(bool force)
{
    QMutexLocker locker(&m_pendingDocumentsMutex);
    if (!force && m_pendingDocuments.size() < MaxPendingDocuments)
        return;

    foreach (CPlusPlus::Document::Ptr doc, m_pendingDocuments) {
        QList<ModelItemInfo> &results = m_searchList[doc->fileName()];
        results = search(doc, results.size() + 10);
    }

    m_pendingDocuments.clear();
    m_pendingDocuments.reserve(MaxPendingDocuments);
}

void CppLocatorFilter::onDocumentUpdated(CPlusPlus::Document::Ptr updatedDoc)
{
    QMutexLocker locker(&m_pendingDocumentsMutex);

    int i = 0, ei = m_pendingDocuments.size();
    for (; i < ei; ++i) {
        const CPlusPlus::Document::Ptr &doc = m_pendingDocuments.at(i);
        if (doc->fileName() == updatedDoc->fileName()
                && doc->revision() < updatedDoc->revision()) {
            m_pendingDocuments[i] = updatedDoc;
            break;
        }
    }

    if (i == ei)
        m_pendingDocuments.append(updatedDoc);

    flushPendingDocument(false);
}

void CppLocatorFilter::onAboutToRemoveFiles(const QStringList &files)
{
    QMutexLocker locker(&m_pendingDocumentsMutex);

    for (int i = 0; i < m_pendingDocuments.size(); ) {
        if (files.contains(m_pendingDocuments.at(i)->fileName()))
            m_pendingDocuments.remove(i);
        else
            ++i;
    }

    foreach (const QString &file, files)
        m_searchList.remove(file);
}

void CppLocatorFilter::refresh(QFutureInterface<void> &future)
{
    Q_UNUSED(future)
}

static bool compareLexigraphically(const Locator::FilterEntry &a,
                                   const Locator::FilterEntry &b)
{
    return a.displayName < b.displayName;
}

QList<Locator::FilterEntry> CppLocatorFilter::matchesFor(QFutureInterface<Locator::FilterEntry> &future, const QString &origEntry)
{
    flushPendingDocument(true);

    QString entry = trimWildcards(origEntry);
    QList<Locator::FilterEntry> goodEntries;
    QList<Locator::FilterEntry> betterEntries;
    const QChar asterisk = QLatin1Char('*');
    QStringMatcher matcher(entry, Qt::CaseInsensitive);
    QRegExp regexp(asterisk + entry+ asterisk, Qt::CaseInsensitive, QRegExp::Wildcard);
    if (!regexp.isValid())
        return goodEntries;
    bool hasWildcard = (entry.contains(asterisk) || entry.contains(QLatin1Char('?')));

    QHashIterator<QString, QList<ModelItemInfo> > it(m_searchList);
    while (it.hasNext()) {
        if (future.isCanceled())
            break;

        it.next();

        const QList<ModelItemInfo> items = it.value();
        foreach (const ModelItemInfo &info, items) {
            if ((hasWildcard && regexp.exactMatch(info.symbolName))
                    || (!hasWildcard && matcher.indexIn(info.symbolName) != -1)) {

                QVariant id = qVariantFromValue(info);
                Locator::FilterEntry filterEntry(this, info.symbolName, id, info.icon);
                if (! info.symbolType.isEmpty()) {
                    filterEntry.extraInfo = info.symbolType;
                } else {
                    filterEntry.extraInfo = FileUtils::shortNativePath(
                        FileName::fromString(info.fileName));
                }

                if (info.symbolName.startsWith(entry))
                    betterEntries.append(filterEntry);
                else
                    goodEntries.append(filterEntry);
            }
        }
    }

    if (goodEntries.size() < 1000)
        qSort(goodEntries.begin(), goodEntries.end(), compareLexigraphically);
    if (betterEntries.size() < 1000)
        qSort(betterEntries.begin(), betterEntries.end(), compareLexigraphically);

    betterEntries += goodEntries;
    return betterEntries;
}

void CppLocatorFilter::accept(Locator::FilterEntry selection) const
{
    ModelItemInfo info = qvariant_cast<CppTools::ModelItemInfo>(selection.internalData);
    TextEditor::BaseTextEditorWidget::openEditorAt(info.fileName, info.line, info.column,
                                             Core::Id(), Core::EditorManager::ModeSwitch);
}

void CppLocatorFilter::reset()
{
    m_searchList.clear();
    m_previousEntry.clear();
}
