qt-creator/src/plugins/classview/classviewmanager.cpp

/****************************************************************************
**
** Copyright (C) 2016 Denis Mingulov
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt Creator.
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#include "classviewmanager.h"
#include "classviewsymbollocation.h"
#include "classviewnavigationwidgetfactory.h"
#include "classviewparser.h"
#include "classviewutils.h"

#include <utils/qtcassert.h>
#include <projectexplorer/projectexplorer.h>
#include <projectexplorer/session.h>
#include <cpptools/cppmodelmanager.h>
#include <cpptools/cpptoolsconstants.h>
#include <coreplugin/progressmanager/progressmanager.h>
#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/editormanager/ieditor.h>
#include <coreplugin/idocument.h>
#include <texteditor/texteditor.h>

#include <QThread>
#include <QMutex>
#include <QMutexLocker>

using namespace Core;
using namespace Utils;

namespace ClassView {
namespace Internal {

///////////////////////////////// ManagerPrivate //////////////////////////////////

// static variable initialization
static Manager *managerInstance = nullptr;

/*!
    \class ClassView::Internal::Manager

    \brief The Manager class implements a class view manager that interacts with
    other \QC plugins and acts as a proxy between them and the parser.

    The parser is moved to a separate thread and is connected to the manager by
    using signals and slots. Manager's signals starting with 'request' are for
    the parser.
*/

/*!
    \fn explicit ClassView::Internal::Manager(QObject *parent = 0)

    Creates a shared instance of a \a parent object.
*/

/*!
    \fn void ClassView::Internal::Manager::treeDataUpdate(QSharedPointer<QStandardItem> result)

    Emits a signal about a tree data update (to tree view). \a result holds the
    item with the current tree.
*/

/*!
   \class ManagerPrivate
   \internal
   \brief The ManagerPrivate class contains private class data for the Manager
    class.
   \sa Manager
*/

class ManagerPrivate
{
public:
    //! code state/changes parser
    Parser parser;

    //! separate thread for the parser
    QThread parserThread;

    //! Internal manager state. \sa Manager::state
    bool state = false;

    //! there is some massive operation ongoing so temporary we should wait
    bool disableCodeParser = false;
};

///////////////////////////////// Manager //////////////////////////////////

Manager::Manager(QObject *parent)
    : QObject(parent),
    d(new ManagerPrivate())
{
    managerInstance = this;

    // register - to be able send between signal/slots
    qRegisterMetaType<QSharedPointer<QStandardItem> >("QSharedPointer<QStandardItem>");

    initialize();

    // start a separate thread for the parser
    d->parser.moveToThread(&d->parserThread);
    d->parserThread.start();
}

Manager::~Manager()
{
    d->parserThread.quit();
    d->parserThread.wait();
    delete d;
    managerInstance = nullptr;
}

Manager *Manager::instance()
{
    return managerInstance;
}

/*!
    Checks \a item for lazy data population of a QStandardItemModel.
*/

bool Manager::canFetchMore(QStandardItem *item, bool skipRoot) const
{
    return d->parser.canFetchMore(item, skipRoot);
}

/*!
    Checks \a item for lazy data population of a QStandardItemModel.
    \a skipRoot item is needed for the manual update, call not from model.
*/

void Manager::fetchMore(QStandardItem *item, bool skipRoot)
{
    d->parser.fetchMore(item, skipRoot);
}

bool Manager::hasChildren(QStandardItem *item) const
{
    return d->parser.hasChildren(item);
}

void Manager::initialize()
{
    using ProjectExplorer::SessionManager;

    // connections to enable/disable navi widget factory
    SessionManager *sessionManager = SessionManager::instance();
    connect(sessionManager, &SessionManager::projectAdded,
            this, &Manager::onProjectListChanged);
    connect(sessionManager, &SessionManager::projectRemoved,
            this, &Manager::onProjectListChanged);

    // connect to the progress manager for signals about Parsing tasks
    connect(ProgressManager::instance(), &ProgressManager::taskStarted,
            this, [this](Id type) {
        if (type != CppTools::Constants::TASK_INDEX)
            return;

        // disable tree updates to speed up
        d->disableCodeParser = true;
    });
    connect(ProgressManager::instance(), &ProgressManager::allTasksFinished,
            this, [this](Id type) {
        if (type != CppTools::Constants::TASK_INDEX)
            return;

        // parsing is finished, enable tree updates
        d->disableCodeParser = false;

        // do nothing if Manager is disabled
        if (!state())
            return;

        // any document might be changed, clear parser's cache
        QMetaObject::invokeMethod(&d->parser, &Parser::clearCache, Qt::QueuedConnection);

        // request to update a tree to the current state
        resetParser();
    });

    // translate data update from the parser to listeners
    connect(&d->parser, &Parser::treeDataUpdate,
            this, &Manager::onTreeDataUpdate, Qt::QueuedConnection);

    // connect to the cpp model manager for signals about document updates
    CppTools::CppModelManager *codeModelManager = CppTools::CppModelManager::instance();

    // when code manager signals that document is updated - handle it by ourselves
    connect(codeModelManager, &CppTools::CppModelManager::documentUpdated,
            this, [this](CPlusPlus::Document::Ptr doc) {
        // do nothing if Manager is disabled
        if (!state())
            return;

        // do nothing if updates are disabled
        if (d->disableCodeParser)
            return;

        QMetaObject::invokeMethod(&d->parser, [this, doc]() {
            d->parser.parseDocument(doc); }, Qt::QueuedConnection);
    }, Qt::QueuedConnection);
    //
    connect(codeModelManager, &CppTools::CppModelManager::aboutToRemoveFiles,
            &d->parser, &Parser::removeFiles, Qt::QueuedConnection);
}

/*!
    Gets the internal manager state. If it is disabled, does not emit signals
    about parsing requests. If enabled, does parsing in the background even if
    the navigation pane is not visible. Returns true if the manager is enabled,
    false otherwise.

   \sa setState, stateChanged
*/

bool Manager::state() const
{
    return d->state;
}

/*!
    Sets the internal manager \a state to \c true if the manager has to be
    enabled, otherwise sets it to \c false.

   \sa state, stateChanged
*/

void Manager::setState(bool state)
{
    if (state == d->state)
        return;

    d->state = state;

    if (state) // enabled - request a current snapshots etc?..
        resetParser();
}

void Manager::resetParser()
{
    QMetaObject::invokeMethod(&d->parser, &Parser::resetDataToCurrentState, Qt::QueuedConnection);
}

/*!
    Reacts to the \a visibility of one navigation pane widget being changed
    (there might be a lot of them).

   \sa setState, state
*/

void Manager::onWidgetVisibilityIsChanged(bool visibility)
{
    // activate data handling - when 1st time 'Class View' will be open
    if (!visibility)
        return;
    setState(true);
    onProjectListChanged();
}

/*!
    Reacts to the project list being changed by updating the navigation pane
    visibility if necessary.
*/

void Manager::onProjectListChanged()
{
    // do nothing if Manager is disabled
    if (!state())
        return;

    QMetaObject::invokeMethod(&d->parser, &Parser::requestCurrentState, Qt::QueuedConnection);
}

/*!
    Opens the text editor for the file \a fileName on \a line (1-based) and
    \a column (0-based).
*/

void Manager::gotoLocation(const QString &fileName, int line, int column)
{
    EditorManager::openEditorAt(fileName, line, column);
}

/*!
    Opens the text editor for any of the symbol locations in the \a list.

   \sa Manager::gotoLocations
*/

void Manager::gotoLocations(const QList<QVariant> &list)
{
    QSet<SymbolLocation> locations = Internal::roleToLocations(list);
    if (locations.size() == 0)
        return;

    // Default to first known location
    SymbolLocation loc = *locations.constBegin();

    if (locations.size() > 1) {
        // The symbol has multiple locations. Check if we are already at one location,
        // and if so, cycle to the "next" one
        auto textEditor = qobject_cast<TextEditor::BaseTextEditor *>(EditorManager::currentEditor());
        if (textEditor) {
            // check if current cursor position is a known location of the symbol
            const QString fileName = textEditor->document()->filePath().toString();
            int line;
            int column;
            textEditor->convertPosition(textEditor->position(), &line, &column);
            SymbolLocation current(fileName, line, column);
            QSet<SymbolLocation>::const_iterator it = locations.constFind(current);
            QSet<SymbolLocation>::const_iterator end = locations.constEnd();
            if (it != end) {
                // we already are at the symbol, cycle to next location
                ++it;
                if (it == end)
                    it = locations.constBegin();
                loc = *it;
            }
        }
    }
    // line is 1-based, column is 0-based
    gotoLocation(loc.fileName(), loc.line(), loc.column() - 1);
}

/*!
    Switches to flat mode (without subprojects) if \a flat is set to \c true.
*/

void Manager::setFlatMode(bool flat)
{
    QMetaObject::invokeMethod(&d->parser, [this, flat]() {
        d->parser.setFlatMode(flat);
    }, Qt::QueuedConnection);
}

/*!
    Sends a new tree data update to a tree view. \a result holds the item with
    the current tree.
*/

void Manager::onTreeDataUpdate(QSharedPointer<QStandardItem> result)
{
    // do nothing if Manager is disabled
    if (!state())
        return;

    emit treeDataUpdate(result);
}

} // namespace Internal
} // namespace ClassView