QString VcsJsExtension::displayName(const QString &vcsId) const
{
    IVersionControl *vc = VcsManager::versionControl(Id::fromString(vcsId));
    return vc ? vc->displayName() : QString();
}
void StateListener::slotStateChanged()
{
    // Get the current file. Are we on a temporary submit editor indicated by
    // temporary path prefix or does the file contains a hash, indicating a project
    // folder?
    State state;
    IDocument *currentDocument = EditorManager::currentDocument();
    if (!currentDocument) {
        state.currentFile.clear();
    } else {
        state.currentFile = currentDocument->filePath().toString();
        if (state.currentFile.isEmpty() || currentDocument->isTemporary())
            state.currentFile = VcsBasePlugin::source(currentDocument);
    }
    QScopedPointer<QFileInfo> currentFileInfo; // Instantiate QFileInfo only once if required.
    if (!state.currentFile.isEmpty()) {
        const bool isTempFile = state.currentFile.startsWith(QDir::tempPath());
        // Quick check: Does it look like a patch?
        const bool isPatch = state.currentFile.endsWith(QLatin1String(".patch"))
                             || state.currentFile.endsWith(QLatin1String(".diff"));
        if (isPatch) {
            // Patch: Figure out a name to display. If it is a temp file, it could be
            // Codepaster. Use the display name of the editor.
            state.currentPatchFile = state.currentFile;
            if (isTempFile)
                state.currentPatchFileDisplayName = displayNameOfEditor(state.currentPatchFile);
            if (state.currentPatchFileDisplayName.isEmpty()) {
                currentFileInfo.reset(new QFileInfo(state.currentFile));
                state.currentPatchFileDisplayName = currentFileInfo->fileName();
            }
        }
        // For actual version control operations on it:
        // Do not show temporary files and project folders ('#')
        if (isTempFile || state.currentFile.contains(QLatin1Char('#')))
            state.currentFile.clear();
    }

    // Get the file and its control. Do not use the file unless we find one
    IVersionControl *fileControl = 0;
    if (!state.currentFile.isEmpty()) {
        if (currentFileInfo.isNull())
            currentFileInfo.reset(new QFileInfo(state.currentFile));
        if (currentFileInfo->isDir()) {
            state.currentFile.clear();
            state.currentFileDirectory = currentFileInfo->absoluteFilePath();
        } else {
            state.currentFileDirectory = currentFileInfo->absolutePath();
            state.currentFileName = currentFileInfo->fileName();
        }
        fileControl = VcsManager::findVersionControlForDirectory(
                    state.currentFileDirectory,
                    &state.currentFileTopLevel);
        if (!fileControl)
            state.clearFile();
    }
    // Check for project, find the control
    IVersionControl *projectControl = 0;
    Project *currentProject = ProjectTree::currentProject();
    if (!currentProject)
        currentProject = SessionManager::startupProject();
    if (currentProject) {
        state.currentProjectPath = currentProject->projectDirectory().toString();
        state.currentProjectName = currentProject->displayName();
        projectControl = VcsManager::findVersionControlForDirectory(state.currentProjectPath,
                                                                    &state.currentProjectTopLevel);
        if (projectControl) {
            // If we have both, let the file's one take preference
            if (fileControl && projectControl != fileControl)
                state.clearProject();
        } else {
            state.clearProject(); // No control found
        }
    }
    // Assemble state and emit signal.
    IVersionControl *vc = fileControl;
    if (!vc)
        vc = projectControl;
    if (!vc)
        state.clearPatchFile(); // Need a repository to patch
    if (debug)
        qDebug() << state << (vc ? vc->displayName() : QLatin1String("No version control"));
    EditorManager::updateWindowTitles();
    emit stateChanged(state, vc);
}