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#include "cpptoolsconstants.h"
#include "cpptoolsplugin.h"
#include "cppfilesettingspage.h"
#include "cppcodemodelsettingspage.h"
#include "cppcodestylesettingspage.h"
#include "cppclassesfilter.h"
#include "cppfunctionsfilter.h"
#include "cppcurrentdocumentfilter.h"
#include "cppmodelmanager.h"
#include "cpplocatorfilter.h"
#include "symbolsfindfilter.h"
#include "cpptoolsjsextension.h"
#include "cpptoolssettings.h"
#include "cpptoolsreuse.h"
#include "cppprojectfile.h"
#include "cpplocatordata.h"
#include "cppincludesfilter.h"

#include <coreplugin/actionmanager/actioncontainer.h>
#include <coreplugin/actionmanager/actionmanager.h>
#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/coreconstants.h>
#include <coreplugin/documentmanager.h>
#include <coreplugin/icore.h>
#include <coreplugin/idocument.h>
#include <coreplugin/jsexpander.h>
#include <coreplugin/vcsmanager.h>
#include <cppeditor/cppeditorconstants.h>
#include <projectexplorer/project.h>
#include <projectexplorer/projecttree.h>

#include <utils/fileutils.h>
#include <utils/hostosinfo.h>
#include <utils/macroexpander.h>
#include <utils/mimetypes/mimedatabase.h>
#include <utils/qtcassert.h>

#include <QtPlugin>
#include <QFileInfo>
#include <QDir>
#include <QDebug>
#include <QMenu>
#include <QAction>

using namespace Core;
using namespace CPlusPlus;

namespace CppTools {
namespace Internal {

enum { debug = 0 };

static CppToolsPlugin *m_instance = 0;
static QHash<QString, QString> m_headerSourceMapping;

CppToolsPlugin::CppToolsPlugin()
    : m_fileSettings(new CppFileSettings)
    , m_codeModelSettings(new CppCodeModelSettings)
{
    m_instance = this;
}

CppToolsPlugin::~CppToolsPlugin()
{
    m_instance = 0;
    delete CppModelManager::instance();
}

CppToolsPlugin *CppToolsPlugin::instance()
{
    return m_instance;
}

void CppToolsPlugin::clearHeaderSourceCache()
{
    m_headerSourceMapping.clear();
}

Utils::FileName CppToolsPlugin::licenseTemplatePath()
{
    return Utils::FileName::fromString(m_instance->m_fileSettings->licenseTemplatePath);
}

QString CppToolsPlugin::licenseTemplate()
{
    return m_instance->m_fileSettings->licenseTemplate();
}

const QStringList &CppToolsPlugin::headerSearchPaths()
{
    return m_instance->m_fileSettings->headerSearchPaths;
}

const QStringList &CppToolsPlugin::sourceSearchPaths()
{
    return m_instance->m_fileSettings->sourceSearchPaths;
}

const QStringList &CppToolsPlugin::headerPrefixes()
{
    return m_instance->m_fileSettings->headerPrefixes;
}

const QStringList &CppToolsPlugin::sourcePrefixes()
{
    return m_instance->m_fileSettings->sourcePrefixes;
}


bool CppToolsPlugin::initialize(const QStringList &arguments, QString *error)
{
    Q_UNUSED(arguments)
    Q_UNUSED(error)

    m_settings = new CppToolsSettings(this); // force registration of cpp tools settings

    // Objects
    CppModelManager *modelManager = CppModelManager::instance();
    connect(VcsManager::instance(), SIGNAL(repositoryChanged(QString)),
            modelManager, SLOT(updateModifiedSourceFiles()));
    connect(DocumentManager::instance(), &DocumentManager::filesChangedInternally,
            [=](const QStringList &files) {
        modelManager->updateSourceFiles(files.toSet());
    });

    JsExpander::registerQObjectForJs(QLatin1String("Cpp"), new CppToolsJsExtension);

    CppLocatorData *locatorData = new CppLocatorData;
    connect(modelManager, &CppModelManager::documentUpdated,
            locatorData, &CppLocatorData::onDocumentUpdated);

    connect(modelManager, &CppModelManager::aboutToRemoveFiles,
            locatorData, &CppLocatorData::onAboutToRemoveFiles);

    addAutoReleasedObject(locatorData);
    addAutoReleasedObject(new CppLocatorFilter(locatorData));
    addAutoReleasedObject(new CppClassesFilter(locatorData));
    addAutoReleasedObject(new CppIncludesFilter);
    addAutoReleasedObject(new CppFunctionsFilter(locatorData));
    addAutoReleasedObject(new CppCurrentDocumentFilter(modelManager, m_stringTable));
    addAutoReleasedObject(new CppFileSettingsPage(m_fileSettings));
    addAutoReleasedObject(new CppCodeModelSettingsPage(m_codeModelSettings));
    addAutoReleasedObject(new SymbolsFindFilter(modelManager));
    addAutoReleasedObject(new CppCodeStyleSettingsPage);

    // Menus
    ActionContainer *mtools = ActionManager::actionContainer(Core::Constants::M_TOOLS);
    ActionContainer *mcpptools = ActionManager::createMenu(CppTools::Constants::M_TOOLS_CPP);
    QMenu *menu = mcpptools->menu();
    menu->setTitle(tr("&C++"));
    menu->setEnabled(true);
    mtools->addMenu(mcpptools);

    // Actions
    Context context(CppEditor::Constants::CPPEDITOR_ID);

    QAction *switchAction = new QAction(tr("Switch Header/Source"), this);
    Command *command = ActionManager::registerAction(switchAction, Constants::SWITCH_HEADER_SOURCE, context, true);
    command->setDefaultKeySequence(QKeySequence(Qt::Key_F4));
    mcpptools->addAction(command);
    connect(switchAction, &QAction::triggered,
            this, &CppToolsPlugin::switchHeaderSource);

    QAction *openInNextSplitAction = new QAction(tr("Open Corresponding Header/Source in Next Split"), this);
    command = ActionManager::registerAction(openInNextSplitAction, Constants::OPEN_HEADER_SOURCE_IN_NEXT_SPLIT, context, true);
    command->setDefaultKeySequence(QKeySequence(Utils::HostOsInfo::isMacHost()
                                                ? tr("Meta+E, F4")
                                                : tr("Ctrl+E, F4")));
    mcpptools->addAction(command);
    connect(openInNextSplitAction, &QAction::triggered,
            this, &CppToolsPlugin::switchHeaderSourceInNextSplit);

    Utils::MacroExpander *expander = Utils::globalMacroExpander();
    expander->registerVariable("Cpp:LicenseTemplate",
                               tr("The license template."),
                               [this]() { return CppToolsPlugin::licenseTemplate(); });
    expander->registerFileVariables("Cpp:LicenseTemplatePath",
                                    tr("The configured path to the license template"),
                                    [this]() { return CppToolsPlugin::licenseTemplatePath().toString(); });

    return true;
}

void CppToolsPlugin::extensionsInitialized()
{
    // The Cpp editor plugin, which is loaded later on, registers the Cpp mime types,
    // so, apply settings here
    m_fileSettings->fromSettings(ICore::settings());
    if (!m_fileSettings->applySuffixesToMimeDB())
        qWarning("Unable to apply cpp suffixes to mime database (cpp mime types not found).\n");
    m_codeModelSettings->fromSettings(ICore::settings());
}

ExtensionSystem::IPlugin::ShutdownFlag CppToolsPlugin::aboutToShutdown()
{
    return SynchronousShutdown;
}

QSharedPointer<CppCodeModelSettings> CppToolsPlugin::codeModelSettings() const
{
    return m_codeModelSettings;
}

StringTable &CppToolsPlugin::stringTable()
{
    return instance()->m_stringTable;
}

void CppToolsPlugin::switchHeaderSource()
{
    CppTools::switchHeaderSource();
}

void CppToolsPlugin::switchHeaderSourceInNextSplit()
{
    QString otherFile = correspondingHeaderOrSource(
                EditorManager::currentDocument()->filePath().toString());
    if (!otherFile.isEmpty())
        EditorManager::openEditor(otherFile, Id(), EditorManager::OpenInOtherSplit);
}

static QStringList findFilesInProject(const QString &name,
                                   const ProjectExplorer::Project *project)
{
    if (debug)
        qDebug() << Q_FUNC_INFO << name << project;

    if (!project)
        return QStringList();

    QString pattern = QString(1, QLatin1Char('/'));
    pattern += name;
    const QStringList projectFiles = project->files(ProjectExplorer::Project::AllFiles);
    const QStringList::const_iterator pcend = projectFiles.constEnd();
    QStringList candidateList;
    for (QStringList::const_iterator it = projectFiles.constBegin(); it != pcend; ++it) {
        if (it->endsWith(pattern))
            candidateList.append(*it);
    }
    return candidateList;
}

// Return the suffixes that should be checked when trying to find a
// source belonging to a header and vice versa
static QStringList matchingCandidateSuffixes(ProjectFile::Kind kind)
{
    Utils::MimeDatabase mdb;
    switch (kind) {
     // Note that C/C++ headers are undistinguishable
    case ProjectFile::CHeader:
    case ProjectFile::CXXHeader:
    case ProjectFile::ObjCHeader:
    case ProjectFile::ObjCXXHeader:
        return mdb.mimeTypeForName(QLatin1String(Constants::C_SOURCE_MIMETYPE)).suffixes()
                + mdb.mimeTypeForName(QLatin1String(Constants::CPP_SOURCE_MIMETYPE)).suffixes()
                + mdb.mimeTypeForName(QLatin1String(Constants::OBJECTIVE_C_SOURCE_MIMETYPE)).suffixes()
                + mdb.mimeTypeForName(QLatin1String(Constants::OBJECTIVE_CPP_SOURCE_MIMETYPE)).suffixes();
    case ProjectFile::CSource:
    case ProjectFile::ObjCSource:
        return mdb.mimeTypeForName(QLatin1String(Constants::C_HEADER_MIMETYPE)).suffixes();
    case ProjectFile::CXXSource:
    case ProjectFile::ObjCXXSource:
    case ProjectFile::CudaSource:
    case ProjectFile::OpenCLSource:
        return mdb.mimeTypeForName(QLatin1String(Constants::CPP_HEADER_MIMETYPE)).suffixes();
    default:
        return QStringList();
    }
}

static QStringList baseNameWithAllSuffixes(const QString &baseName, const QStringList &suffixes)
{
    QStringList result;
    const QChar dot = QLatin1Char('.');
    foreach (const QString &suffix, suffixes) {
        QString fileName = baseName;
        fileName += dot;
        fileName += suffix;
        result += fileName;
    }
    return result;
}

static QStringList baseNamesWithAllPrefixes(const QStringList &baseNames, bool isHeader)
{
    QStringList result;
    const QStringList &sourcePrefixes = m_instance->sourcePrefixes();
    const QStringList &headerPrefixes = m_instance->headerPrefixes();

    foreach (const QString &name, baseNames) {
        foreach (const QString &prefix, isHeader ? headerPrefixes : sourcePrefixes) {
            if (name.startsWith(prefix)) {
                QString nameWithoutPrefix = name.mid(prefix.size());
                result += nameWithoutPrefix;
                foreach (const QString &prefix, isHeader ? sourcePrefixes : headerPrefixes)
                    result += prefix + nameWithoutPrefix;
            }
        }
        foreach (const QString &prefix, isHeader ? sourcePrefixes : headerPrefixes)
            result += prefix + name;

    }
    return result;
}

static QStringList baseDirWithAllDirectories(const QDir &baseDir, const QStringList &directories)
{
    QStringList result;
    foreach (const QString &dir, directories)
        result << QDir::cleanPath(baseDir.absoluteFilePath(dir));
    return result;
}

static int commonStringLength(const QString &s1, const QString &s2)
{
    int length = qMin(s1.length(), s2.length());
    for (int i = 0; i < length; ++i)
        if (s1[i] != s2[i])
            return i;
    return length;
}

static QString correspondingHeaderOrSourceInProject(const QFileInfo &fileInfo,
                                                    const QStringList &candidateFileNames,
                                                    const ProjectExplorer::Project *project)
{
    QString bestFileName;
    int compareValue = 0;
    const QString filePath = fileInfo.filePath();
    foreach (const QString &candidateFileName, candidateFileNames) {
        const QStringList projectFiles = findFilesInProject(candidateFileName, project);
        // Find the file having the most common path with fileName
        foreach (const QString &projectFile, projectFiles) {
            int value = commonStringLength(filePath, projectFile);
            if (value > compareValue) {
                compareValue = value;
                bestFileName = projectFile;
            }
        }
    }
    if (!bestFileName.isEmpty()) {
        const QFileInfo candidateFi(bestFileName);
        QTC_ASSERT(candidateFi.isFile(), return QString());
        m_headerSourceMapping[fileInfo.absoluteFilePath()] = candidateFi.absoluteFilePath();
        m_headerSourceMapping[candidateFi.absoluteFilePath()] = fileInfo.absoluteFilePath();
        return candidateFi.absoluteFilePath();
    }

    return QString();
}

} // namespace Internal

QString correspondingHeaderOrSource(const QString &fileName, bool *wasHeader)
{
    using namespace Internal;

    const QFileInfo fi(fileName);
    ProjectFile::Kind kind = ProjectFile::classify(fileName);
    const bool isHeader = ProjectFile::isHeader(kind);
    if (wasHeader)
        *wasHeader = isHeader;
    if (m_headerSourceMapping.contains(fi.absoluteFilePath()))
        return m_headerSourceMapping.value(fi.absoluteFilePath());

    if (debug)
        qDebug() << Q_FUNC_INFO << fileName <<  kind;

    if (kind == ProjectFile::Unclassified)
        return QString();

    const QString baseName = fi.completeBaseName();
    const QString privateHeaderSuffix = QLatin1String("_p");
    const QStringList suffixes = matchingCandidateSuffixes(kind);

    QStringList candidateFileNames = baseNameWithAllSuffixes(baseName, suffixes);
    if (isHeader) {
        if (baseName.endsWith(privateHeaderSuffix)) {
            QString sourceBaseName = baseName;
            sourceBaseName.truncate(sourceBaseName.size() - privateHeaderSuffix.size());
            candidateFileNames += baseNameWithAllSuffixes(sourceBaseName, suffixes);
        }
    } else {
        QString privateHeaderBaseName = baseName;
        privateHeaderBaseName.append(privateHeaderSuffix);
        candidateFileNames += baseNameWithAllSuffixes(privateHeaderBaseName, suffixes);
    }

    const QDir absoluteDir = fi.absoluteDir();
    QStringList candidateDirs(absoluteDir.absolutePath());
    // If directory is not root, try matching against its siblings
    const QStringList searchPaths = isHeader ? m_instance->sourceSearchPaths()
                                             : m_instance->headerSearchPaths();
    candidateDirs += baseDirWithAllDirectories(absoluteDir, searchPaths);

    candidateFileNames += baseNamesWithAllPrefixes(candidateFileNames, isHeader);

    // Try to find a file in the same or sibling directories first
    foreach (const QString &candidateDir, candidateDirs) {
        foreach (const QString &candidateFileName, candidateFileNames) {
            const QString candidateFilePath = candidateDir + QLatin1Char('/') + candidateFileName;
            const QString normalized = Utils::FileUtils::normalizePathName(candidateFilePath);
            const QFileInfo candidateFi(normalized);
            if (candidateFi.isFile()) {
                m_headerSourceMapping[fi.absoluteFilePath()] = candidateFi.absoluteFilePath();
                if (!isHeader || !baseName.endsWith(privateHeaderSuffix))
                    m_headerSourceMapping[candidateFi.absoluteFilePath()] = fi.absoluteFilePath();
                return candidateFi.absoluteFilePath();
            }
        }
    }

    // Find files in the current project
    ProjectExplorer::Project *currentProject = ProjectExplorer::ProjectTree::currentProject();
    if (currentProject) {
        const QString path = correspondingHeaderOrSourceInProject(fi, candidateFileNames,
                                                                  currentProject);
        if (!path.isEmpty())
            return path;

    // Find files in other projects
    } else {
        CppModelManager *modelManager = CppModelManager::instance();
        QList<ProjectInfo> projectInfos = modelManager->projectInfos();
        foreach (const ProjectInfo &projectInfo, projectInfos) {
            const ProjectExplorer::Project *project = projectInfo.project().data();
            if (project == currentProject)
                continue; // We have already checked the current project.

            const QString path = correspondingHeaderOrSourceInProject(fi, candidateFileNames, project);
            if (!path.isEmpty())
                return path;
        }
    }

    return QString();
}

} // namespace CppTools
