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#include "vcsbaseoutputwindow.h"

#include <utils/qtcassert.h>
#include <coreplugin/editormanager/editormanager.h>

#include <QPlainTextEdit>
#include <QTextCharFormat>
#include <QContextMenuEvent>
#include <QTextBlock>
#include <QMenu>
#include <QAction>
#include <QTextDocument>
#include <QTextBlockUserData>

#include <QPointer>
#include <QTextCodec>
#include <QDir>
#include <QTextStream>
#include <QTime>
#include <QPoint>
#include <QFileInfo>

/*!
    \class VcsBase::VcsBaseOutputWindow

    \brief Output window for Version Control System command and other output (Singleton).

    Installed by the base plugin and accessible for the other plugins
    via static instance()-accessor. Provides slots to append output with
    special formatting.

    It is possible to associate a repository with plain log text, enabling
    an "Open" context menu action over relative file name tokens in the text
    (absolute paths will also work). This can be used for "status" logs,
    showing modified file names, allowing the user to open them.
*/

namespace VcsBase {

namespace Internal {

// Store repository along with text blocks
class RepositoryUserData : public QTextBlockUserData
{
public:
    explicit RepositoryUserData(const QString &repo) : m_repository(repo) {}
    const QString &repository() const { return m_repository; }

private:
    const QString m_repository;
};

// A plain text edit with a special context menu containing "Clear" and
// and functions to append specially formatted entries.
class OutputWindowPlainTextEdit : public QPlainTextEdit
{
public:
    explicit OutputWindowPlainTextEdit(QWidget *parent = 0);

    void appendLines(QString s, const QString &repository = QString());
    // Append red error text and pop up.
    void appendError(const QString &text);
    // Append warning error text and pop up.
    void appendWarning(const QString &text);
    // Append a bold command "10:00 " + "Executing: vcs -diff"
    void appendCommand(const QString &text);

protected:
    virtual void contextMenuEvent(QContextMenuEvent *event);

private:
    QString identifierUnderCursor(const QPoint &pos, QString *repository = 0) const;

    const QTextCharFormat m_defaultFormat;
    QTextCharFormat m_errorFormat;
    QTextCharFormat m_warningFormat;
    QTextCharFormat m_commandFormat;
};

OutputWindowPlainTextEdit::OutputWindowPlainTextEdit(QWidget *parent) :
    QPlainTextEdit(parent),
    m_defaultFormat(currentCharFormat()),
    m_errorFormat(m_defaultFormat),
    m_warningFormat(m_defaultFormat),
    m_commandFormat(m_defaultFormat)
{
    setReadOnly(true);
    setFrameStyle(QFrame::NoFrame);
    m_errorFormat.setForeground(Qt::red);
    m_warningFormat.setForeground(Qt::darkYellow);
    m_commandFormat.setFontWeight(QFont::Bold);
}

// Search back for beginning of word
static inline int firstWordCharacter(const QString &s, int startPos)
{
    for ( ; startPos >= 0 ; startPos--) {
        if (s.at(startPos).isSpace())
            return startPos + 1;
    }
    return 0;
}

QString OutputWindowPlainTextEdit::identifierUnderCursor(const QPoint &widgetPos, QString *repository) const
{
    if (repository)
        repository->clear();
    // Get the blank-delimited word under cursor. Note that
    // using "SelectWordUnderCursor" does not work since it breaks
    // at delimiters like '/'. Get the whole line
    QTextCursor cursor = cursorForPosition(widgetPos);
    const int cursorDocumentPos = cursor.position();
    cursor.select(QTextCursor::BlockUnderCursor);
    if (!cursor.hasSelection())
        return QString();
    QString block = cursor.selectedText();
    // Determine cursor position within line and find blank-delimited word
    const int cursorPos = cursorDocumentPos - cursor.block().position();
    const int blockSize = block.size();
    if (cursorPos < 0 || cursorPos >= blockSize || block.at(cursorPos).isSpace())
        return QString();
    // Retrieve repository if desired
    if (repository)
        if (QTextBlockUserData *data = cursor.block().userData())
            *repository = static_cast<const RepositoryUserData*>(data)->repository();
    // Find first non-space character of word and find first non-space character past
    const int startPos = firstWordCharacter(block, cursorPos);
    int endPos = cursorPos;
    for ( ; endPos < blockSize && !block.at(endPos).isSpace(); endPos++) ;
    return endPos > startPos ? block.mid(startPos, endPos - startPos) : QString();
}

void OutputWindowPlainTextEdit::contextMenuEvent(QContextMenuEvent *event)
{
    QMenu *menu = createStandardContextMenu();
    // Add 'open file'
    QString repository;
    const QString token = identifierUnderCursor(event->pos(), &repository);
    QAction *openAction = 0;
    if (!token.isEmpty()) {
        // Check for a file, expand via repository if relative
        QFileInfo fi(token);
        if (!repository.isEmpty() && !fi.isFile() && fi.isRelative())
            fi = QFileInfo(repository + QLatin1Char('/') + token);
        if (fi.isFile())  {
            menu->addSeparator();
            openAction = menu->addAction(VcsBaseOutputWindow::tr("Open \"%1\"").
                                         arg(QDir::toNativeSeparators(fi.fileName())));
            openAction->setData(fi.absoluteFilePath());
        }
    }
    // Add 'clear'
    menu->addSeparator();
    QAction *clearAction = menu->addAction(VcsBaseOutputWindow::tr("Clear"));

    // Run
    QAction *action = menu->exec(event->globalPos());
    if (action) {
        if (action == clearAction) {
            clear();
            return;
        }
        if (action == openAction) {
            const QString fileName = action->data().toString();
            Core::EditorManager::openEditor(fileName, Core::Id(), Core::EditorManager::ModeSwitch);
        }
    }
    delete menu;
}

void OutputWindowPlainTextEdit::appendLines(QString s, const QString &repository)
{
    if (s.isEmpty())
        return;
    // Avoid additional new line character generated by appendPlainText
    if (s.endsWith(QLatin1Char('\n')))
        s.truncate(s.size() - 1);
    const int previousLineCount = document()->lineCount();
    appendPlainText(s);
    // Scroll down
    moveCursor(QTextCursor::End);
    ensureCursorVisible();
    if (!repository.isEmpty()) {
        // Associate repository with new data.
        QTextBlock block = document()->findBlockByLineNumber(previousLineCount);
        for ( ; block.isValid(); block = block.next())
            block.setUserData(new RepositoryUserData(repository));
    }
}

void OutputWindowPlainTextEdit::appendError(const QString &text)
{
    setCurrentCharFormat(m_errorFormat);
    appendLines(text);
    setCurrentCharFormat(m_defaultFormat);
}

void OutputWindowPlainTextEdit::appendWarning(const QString &text)
{
    setCurrentCharFormat(m_warningFormat);
    appendLines(text);
    setCurrentCharFormat(m_defaultFormat);
}

// Append command with new line and log time stamp
void OutputWindowPlainTextEdit::appendCommand(const QString &text)
{
    setCurrentCharFormat(m_commandFormat);
    const QString timeStamp = QTime::currentTime().toString(QLatin1String("\nHH:mm "));
    appendLines(timeStamp + text);
    setCurrentCharFormat(m_defaultFormat);
}

} // namespace Internal

// ------------------- VcsBaseOutputWindowPrivate
struct VcsBaseOutputWindowPrivate
{
    static VcsBaseOutputWindow *instance;
    Internal::OutputWindowPlainTextEdit *plainTextEdit();

    QPointer<Internal::OutputWindowPlainTextEdit> m_plainTextEdit;
    QString repository;
};

// Create log editor on demand. Some errors might be logged
// before CorePlugin::extensionsInitialized() pulls up the windows.

Internal::OutputWindowPlainTextEdit *VcsBaseOutputWindowPrivate::plainTextEdit()
{
    if (!m_plainTextEdit)
        m_plainTextEdit = new Internal::OutputWindowPlainTextEdit();
    return m_plainTextEdit;
}

VcsBaseOutputWindow *VcsBaseOutputWindowPrivate::instance = 0;

VcsBaseOutputWindow::VcsBaseOutputWindow() :
    d(new VcsBaseOutputWindowPrivate)
{
    VcsBaseOutputWindowPrivate::instance = this;
}

VcsBaseOutputWindow::~VcsBaseOutputWindow()
{
    VcsBaseOutputWindowPrivate::instance = 0;
    delete d;
}

QWidget *VcsBaseOutputWindow::outputWidget(QWidget *parent)
{
    if (d->m_plainTextEdit) {
        if (parent != d->m_plainTextEdit->parent())
            d->m_plainTextEdit->setParent(parent);
    } else {
        d->m_plainTextEdit = new Internal::OutputWindowPlainTextEdit(parent);
    }
    return d->m_plainTextEdit;
}

QWidgetList VcsBaseOutputWindow::toolBarWidgets() const
{
    return QWidgetList();
}

QString VcsBaseOutputWindow::displayName() const
{
    return tr("Version Control");
}

int VcsBaseOutputWindow::priorityInStatusBar() const
{
    return -1;
}

void VcsBaseOutputWindow::clearContents()
{
    if (d->m_plainTextEdit)
        d->m_plainTextEdit->clear();
}

void VcsBaseOutputWindow::visibilityChanged(bool visible)
{
    if (visible && d->m_plainTextEdit)
        d->m_plainTextEdit->setFocus();
}

void VcsBaseOutputWindow::setFocus()
{
}

bool VcsBaseOutputWindow::hasFocus() const
{
    return false;
}

bool VcsBaseOutputWindow::canFocus() const
{
    return false;
}

bool VcsBaseOutputWindow::canNavigate() const
{
    return false;
}

bool VcsBaseOutputWindow::canNext() const
{
    return false;
}

bool VcsBaseOutputWindow::canPrevious() const
{
    return false;
}

void VcsBaseOutputWindow::goToNext()
{
}

void VcsBaseOutputWindow::goToPrev()
{
}

void VcsBaseOutputWindow::setText(const QString &text)
{
    d->plainTextEdit()->setPlainText(text);
}

void VcsBaseOutputWindow::setData(const QByteArray &data)
{
    setText(QTextCodec::codecForLocale()->toUnicode(data));
}

void VcsBaseOutputWindow::appendSilently(const QString &text)
{
    d->plainTextEdit()->appendLines(text, d->repository);
}

void VcsBaseOutputWindow::append(const QString &text)
{
    appendSilently(text);
    if (!d->plainTextEdit()->isVisible())
        popup(Core::IOutputPane::NoModeSwitch);
}

void VcsBaseOutputWindow::appendError(const QString &text)
{
    d->plainTextEdit()->appendError(text);
    if (!d->plainTextEdit()->isVisible())
        popup(Core::IOutputPane::NoModeSwitch);
}

void VcsBaseOutputWindow::appendWarning(const QString &text)
{
    d->plainTextEdit()->appendWarning(text);
    if (!d->plainTextEdit()->isVisible())
        popup(Core::IOutputPane::NoModeSwitch);
}

// Helper to format arguments for log windows hiding common password
// options.
static inline QString formatArguments(const QStringList &args)
{
    const char passwordOptionC[] = "--password";

    QString rc;
    QTextStream str(&rc);
    const int size = args.size();
    // Skip authentication options
    for (int i = 0; i < size; i++) {
        const QString &arg = args.at(i);
        if (i)
            str << ' ';
        str << arg;
        if (arg == QLatin1String(passwordOptionC)) {
            str << " ********";
            i++;
        }
    }
    return rc;
}

QString VcsBaseOutputWindow::msgExecutionLogEntry(const QString &workingDir,
                                                  const QString &executable,
                                                  const QStringList &arguments)
{
    const QString args = formatArguments(arguments);
    const QString nativeExecutable = QDir::toNativeSeparators(executable);
    if (workingDir.isEmpty())
        return tr("Executing: %1 %2\n").arg(nativeExecutable, args);
    return tr("Executing in %1: %2 %3\n").
            arg(QDir::toNativeSeparators(workingDir), nativeExecutable, args);
}

void VcsBaseOutputWindow::appendCommand(const QString &text)
{
    d->plainTextEdit()->appendCommand(text);
}

void VcsBaseOutputWindow::appendCommand(const QString &workingDirectory,
                                        const QString &binary,
                                        const QStringList &args)
{
    appendCommand(msgExecutionLogEntry(workingDirectory, binary, args));
}


void VcsBaseOutputWindow::appendData(const QByteArray &data)
{
    appendDataSilently(data);
    if (!d->plainTextEdit()->isVisible())
        popup(Core::IOutputPane::NoModeSwitch);
}

void VcsBaseOutputWindow::appendDataSilently(const QByteArray &data)
{
    appendSilently(QTextCodec::codecForLocale()->toUnicode(data));
}

VcsBaseOutputWindow *VcsBaseOutputWindow::instance()
{
    if (!VcsBaseOutputWindowPrivate::instance) {
        VcsBaseOutputWindow *w = new VcsBaseOutputWindow;
        Q_UNUSED(w)
    }
    return VcsBaseOutputWindowPrivate::instance;
}

QString VcsBaseOutputWindow::repository() const
{
    return d->repository;
}

void VcsBaseOutputWindow::setRepository(const QString &r)
{
    d->repository = r;
}

void VcsBaseOutputWindow::clearRepository()
{
    d->repository.clear();
}

} // namespace VcsBase
