/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2011 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: Nokia Corporation (info@qt.nokia.com)
**
**
** GNU Lesser General Public License Usage
**
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this file.
** Please review the following information to ensure the GNU Lesser General
** Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** Other Usage
**
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
** If you have questions regarding the use of this file, please contact
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#include "vcsbaseeditor.h"
#include "diffhighlighter.h"
#include "baseannotationhighlighter.h"
#include "vcsbasetextdocument.h"
#include "vcsbaseconstants.h"
#include "vcsbaseoutputwindow.h"
#include "vcsbaseplugin.h"

#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/ifile.h>
#include <coreplugin/iversioncontrol.h>
#include <coreplugin/coreconstants.h>
#include <coreplugin/modemanager.h>
#include <extensionsystem/pluginmanager.h>
#include <projectexplorer/editorconfiguration.h>
#include <projectexplorer/projectexplorer.h>
#include <projectexplorer/project.h>
#include <projectexplorer/session.h>
#include <texteditor/basetextdocumentlayout.h>
#include <texteditor/fontsettings.h>
#include <texteditor/texteditorconstants.h>
#include <texteditor/texteditorsettings.h>
#include <utils/qtcassert.h>
#include <extensionsystem/invoker.h>
#include <extensionsystem/pluginmanager.h>

#include <QtCore/QDebug>
#include <QtCore/QFileInfo>
#include <QtCore/QFile>
#include <QtCore/QProcess>
#include <QtCore/QRegExp>
#include <QtCore/QSet>
#include <QtCore/QTextCodec>
#include <QtCore/QTextStream>
#include <QtGui/QTextBlock>
#include <QtGui/QAction>
#include <QtGui/QKeyEvent>
#include <QtGui/QLayout>
#include <QtGui/QMenu>
#include <QtGui/QTextCursor>
#include <QtGui/QTextEdit>
#include <QtGui/QComboBox>
#include <QtGui/QToolBar>
#include <QtGui/QClipboard>
#include <QtGui/QApplication>
#include <QtGui/QMessageBox>

/*!
    \enum VCSBase::EditorContentType

    \brief Contents of a VCSBaseEditor and its interaction.

    \value RegularCommandOutput  No special handling.
    \value LogOutput  Log of a file under revision control. Provide  'click on change'
           description and 'Annotate' if is the log of a single file.
    \value AnnotateOutput  Color contents per change number and provide 'click on change' description.
           Context menu offers "Annotate previous version". Expected format:
           \code
           <change description>: file line
           \endcode
    \value DiffOutput  Diff output. Might includes describe output, which consists of a
           header and diffs. Interaction is 'double click in  hunk' which
           opens the file. Context menu offers 'Revert chunk'.

    \sa VCSBase::VCSBaseEditorWidget
*/

namespace VCSBase {

/*!
    \class VCSBase::DiffChunk

    \brief A diff chunk consisting of file name and chunk data.
*/

bool DiffChunk::isValid() const
{
    return !fileName.isEmpty() && !chunk.isEmpty();
}

QByteArray DiffChunk::asPatch() const
{
    const QByteArray fileNameBA = QFile::encodeName(fileName);
    QByteArray rc = "--- ";
    rc += fileNameBA;
    rc += "\n+++ ";
    rc += fileNameBA;
    rc += '\n';
    rc += chunk;
    return rc;
}

/*!
    \class VCSBase::VCSBaseEditor

    \brief An editor with no support for duplicates.

    Creates a browse combo in the toolbar for diff output.
    It also mirrors the signals of the VCSBaseEditor since the editor
    manager passes the editor around.
*/

class VCSBaseEditor : public TextEditor::BaseTextEditor
{
    Q_OBJECT
public:
    VCSBaseEditor(VCSBaseEditorWidget *, const VCSBaseEditorParameters *type);

    bool duplicateSupported() const { return false; }
    Core::IEditor *duplicate(QWidget * /*parent*/) { return 0; }
    QString id() const { return m_id; }

    bool isTemporary() const { return m_temporary; }
    void setTemporary(bool t) { m_temporary = t; }

signals:
    void describeRequested(const QString &source, const QString &change);
    void annotateRevisionRequested(const QString &source, const QString &change, int line);

private:
    QString m_id;
    bool m_temporary;
};

VCSBaseEditor::VCSBaseEditor(VCSBaseEditorWidget *widget,
                             const VCSBaseEditorParameters *type)  :
    BaseTextEditor(widget),
    m_id(type->id),
    m_temporary(false)
{
    setContext(Core::Context(type->context, TextEditor::Constants::C_TEXTEDITOR));
}

// Diff editor: creates a browse combo in the toolbar for diff output.
class VCSBaseDiffEditor : public VCSBaseEditor
{
public:
    VCSBaseDiffEditor(VCSBaseEditorWidget *, const VCSBaseEditorParameters *type);

    QComboBox *diffFileBrowseComboBox() const { return m_diffFileBrowseComboBox; }

private:
    QComboBox *m_diffFileBrowseComboBox;
};

VCSBaseDiffEditor::VCSBaseDiffEditor(VCSBaseEditorWidget *w, const VCSBaseEditorParameters *type) :
    VCSBaseEditor(w, type),
    m_diffFileBrowseComboBox(new QComboBox)
{
    m_diffFileBrowseComboBox->setMinimumContentsLength(20);
    // Make the combo box prefer to expand
    QSizePolicy policy = m_diffFileBrowseComboBox->sizePolicy();
    policy.setHorizontalPolicy(QSizePolicy::Expanding);
    m_diffFileBrowseComboBox->setSizePolicy(policy);

    insertExtraToolBarWidget(Left, m_diffFileBrowseComboBox);
}

// ----------- VCSBaseEditorPrivate

struct VCSBaseEditorWidgetPrivate
{
    VCSBaseEditorWidgetPrivate(const VCSBaseEditorParameters *type);

    const VCSBaseEditorParameters *m_parameters;

    QString m_currentChange;
    QString m_source;
    QString m_diffBaseDirectory;

    QRegExp m_diffFilePattern;
    QList<int> m_diffSections; // line number where this section starts
    int m_cursorLine;
    QString m_annotateRevisionTextFormat;
    QString m_annotatePreviousRevisionTextFormat;
    QString m_copyRevisionTextFormat;
    bool m_fileLogAnnotateEnabled;
    TextEditor::BaseTextEditor *m_editor;
    QWidget *m_configurationWidget;
    bool m_revertChunkEnabled;
    bool m_mouseDragging;
};

VCSBaseEditorWidgetPrivate::VCSBaseEditorWidgetPrivate(const VCSBaseEditorParameters *type)  :
    m_parameters(type),
    m_cursorLine(-1),
    m_annotateRevisionTextFormat(VCSBaseEditorWidget::tr("Annotate \"%1\"")),
    m_copyRevisionTextFormat(VCSBaseEditorWidget::tr("Copy \"%1\"")),
    m_fileLogAnnotateEnabled(false),
    m_editor(0),
    m_configurationWidget(0),
    m_revertChunkEnabled(false),
    m_mouseDragging(false)
{
}

/*!
    \struct VCSBase::VCSBaseEditorParameters

    \brief Helper struct used to parametrize an editor with mime type, context
    and id. The extension is currently only a suggestion when running
    VCS commands with redirection.

    \sa VCSBase::VCSBaseEditorWidget, VCSBase::BaseVCSEditorFactory, VCSBase::EditorContentType
*/

/*!
    \class VCSBase::VCSBaseEditorWidget

    \brief Base class for editors showing version control system output
    of the type enumerated by EditorContentType.

    The source property should contain the file or directory the log
    refers to and will be emitted with describeRequested().
    This is for VCS that need a current directory.

    \sa VCSBase::BaseVCSEditorFactory, VCSBase::VCSBaseEditorParameters, VCSBase::EditorContentType
*/

VCSBaseEditorWidget::VCSBaseEditorWidget(const VCSBaseEditorParameters *type, QWidget *parent)
  : BaseTextEditorWidget(parent),
    d(new VCSBaseEditorWidgetPrivate(type))
{
    if (VCSBase::Constants::Internal::debug)
        qDebug() << "VCSBaseEditor::VCSBaseEditor" << type->type << type->id;

    viewport()->setMouseTracking(true);
    setBaseTextDocument(new Internal::VCSBaseTextDocument);
    setMimeType(QLatin1String(d->m_parameters->mimeType));
}

void VCSBaseEditorWidget::init()
{
    switch (d->m_parameters->type) {
    case RegularCommandOutput:
    case LogOutput:
    case AnnotateOutput:
        // Annotation highlighting depends on contents, which is set later on
        connect(this, SIGNAL(textChanged()), this, SLOT(slotActivateAnnotation()));
        break;
    case DiffOutput: {
        DiffHighlighter *dh = createDiffHighlighter();
        setCodeFoldingSupported(true);
        baseTextDocument()->setSyntaxHighlighter(dh);
        d->m_diffFilePattern = dh->filePattern();
        connect(this, SIGNAL(textChanged()), this, SLOT(slotPopulateDiffBrowser()));
        connect(this, SIGNAL(cursorPositionChanged()), this, SLOT(slotDiffCursorPositionChanged()));
    }
        break;
    }
    TextEditor::TextEditorSettings::instance()->initializeEditor(this);
}

VCSBaseEditorWidget::~VCSBaseEditorWidget()
{
    delete d;
}

void VCSBaseEditorWidget::setForceReadOnly(bool b)
{
    Internal::VCSBaseTextDocument *vbd = qobject_cast<Internal::VCSBaseTextDocument*>(baseTextDocument());
    VCSBaseEditor *eda = qobject_cast<VCSBaseEditor *>(editor());
    QTC_ASSERT(vbd != 0 && eda != 0, return);
    setReadOnly(b);
    vbd->setForceReadOnly(b);
    eda->setTemporary(b);
}

bool VCSBaseEditorWidget::isForceReadOnly() const
{
    const Internal::VCSBaseTextDocument *vbd = qobject_cast<const Internal::VCSBaseTextDocument*>(baseTextDocument());
    QTC_ASSERT(vbd, return false);
    return vbd->isForceReadOnly();
}

QString VCSBaseEditorWidget::source() const
{
    return d->m_source;
}

void VCSBaseEditorWidget::setSource(const  QString &source)
{
    d->m_source = source;
}

QString VCSBaseEditorWidget::annotateRevisionTextFormat() const
{
    return d->m_annotateRevisionTextFormat;
}

void VCSBaseEditorWidget::setAnnotateRevisionTextFormat(const QString &f)
{
    d->m_annotateRevisionTextFormat = f;
}

QString VCSBaseEditorWidget::annotatePreviousRevisionTextFormat() const
{
    return d->m_annotatePreviousRevisionTextFormat;
}

void VCSBaseEditorWidget::setAnnotatePreviousRevisionTextFormat(const QString &f)
{
    d->m_annotatePreviousRevisionTextFormat = f;
}

QString VCSBaseEditorWidget::copyRevisionTextFormat() const
{
    return d->m_copyRevisionTextFormat;
}

void VCSBaseEditorWidget::setCopyRevisionTextFormat(const QString &f)
{
    d->m_copyRevisionTextFormat = f;
}

bool VCSBaseEditorWidget::isFileLogAnnotateEnabled() const
{
    return d->m_fileLogAnnotateEnabled;
}

void VCSBaseEditorWidget::setFileLogAnnotateEnabled(bool e)
{
    d->m_fileLogAnnotateEnabled = e;
}

QString VCSBaseEditorWidget::diffBaseDirectory() const
{
    return d->m_diffBaseDirectory;
}

void VCSBaseEditorWidget::setDiffBaseDirectory(const QString &bd)
{
    d->m_diffBaseDirectory = bd;
}

QTextCodec *VCSBaseEditorWidget::codec() const
{
    return baseTextDocument()->codec();
}

void VCSBaseEditorWidget::setCodec(QTextCodec *c)
{
    if (c) {
        baseTextDocument()->setCodec(c);
    } else {
        qWarning("%s: Attempt to set 0 codec.", Q_FUNC_INFO);
    }
}

EditorContentType VCSBaseEditorWidget::contentType() const
{
    return d->m_parameters->type;
}

bool VCSBaseEditorWidget::isModified() const
{
    return false;
}

TextEditor::BaseTextEditor *VCSBaseEditorWidget::createEditor()
{
    TextEditor::BaseTextEditor *editor = 0;
    if (d->m_parameters->type == DiffOutput) {
        // Diff: set up diff file browsing
        VCSBaseDiffEditor *de = new VCSBaseDiffEditor(this, d->m_parameters);
        QComboBox *diffBrowseComboBox = de->diffFileBrowseComboBox();
        connect(diffBrowseComboBox, SIGNAL(activated(int)), this, SLOT(slotDiffBrowse(int)));
        editor = de;
    } else {
        editor = new VCSBaseEditor(this, d->m_parameters);
    }
    d->m_editor = editor;

    // Pass on signals.
    connect(this, SIGNAL(describeRequested(QString,QString)),
            editor, SIGNAL(describeRequested(QString,QString)));
    connect(this, SIGNAL(annotateRevisionRequested(QString,QString,int)),
            editor, SIGNAL(annotateRevisionRequested(QString,QString,int)));
    return editor;
}

void VCSBaseEditorWidget::slotPopulateDiffBrowser()
{
    VCSBaseDiffEditor *de = static_cast<VCSBaseDiffEditor*>(editor());
    QComboBox *diffBrowseComboBox = de->diffFileBrowseComboBox();
    diffBrowseComboBox->clear();
    d->m_diffSections.clear();
    // Create a list of section line numbers (diffed files)
    // and populate combo with filenames.
    const QTextBlock cend = document()->end();
    int lineNumber = 0;
    QString lastFileName;
    for (QTextBlock it = document()->begin(); it != cend; it = it.next(), lineNumber++) {
        const QString text = it.text();
        // Check for a new diff section (not repeating the last filename)
        if (d->m_diffFilePattern.exactMatch(text)) {
            const QString file = fileNameFromDiffSpecification(it);
            if (!file.isEmpty() && lastFileName != file) {
                lastFileName = file;
                // ignore any headers
                d->m_diffSections.push_back(d->m_diffSections.empty() ? 0 : lineNumber);
                diffBrowseComboBox->addItem(QFileInfo(file).fileName());
            }
        }
    }
}

void VCSBaseEditorWidget::slotDiffBrowse(int index)
{
    // goto diffed file as indicated by index/line number
    if (index < 0 || index >= d->m_diffSections.size())
        return;
    const int lineNumber = d->m_diffSections.at(index) + 1; // TextEdit uses 1..n convention
    // check if we need to do something, especially to avoid messing up navigation history
    int currentLine, currentColumn;
    convertPosition(position(), &currentLine, &currentColumn);
    if (lineNumber != currentLine) {
        Core::EditorManager *editorManager = Core::EditorManager::instance();
        editorManager->addCurrentPositionToNavigationHistory();
        gotoLine(lineNumber, 0);
    }
}

// Locate a line number in the list of diff sections.
static int sectionOfLine(int line, const QList<int> &sections)
{
    const int sectionCount = sections.size();
    if (!sectionCount)
        return -1;
    // The section at s indicates where the section begins.
    for (int s = 0; s < sectionCount; s++) {
        if (line < sections.at(s))
            return s - 1;
    }
    return sectionCount - 1;
}

void VCSBaseEditorWidget::slotDiffCursorPositionChanged()
{
    // Adapt diff file browse combo to new position
    // if the cursor goes across a file line.
    QTC_ASSERT(d->m_parameters->type == DiffOutput, return)
    const int newCursorLine = textCursor().blockNumber();
    if (newCursorLine == d->m_cursorLine)
        return;
    // Which section does it belong to?
    d->m_cursorLine = newCursorLine;
    const int section = sectionOfLine(d->m_cursorLine, d->m_diffSections);
    if (section != -1) {
        VCSBaseDiffEditor *de = static_cast<VCSBaseDiffEditor*>(editor());
        QComboBox *diffBrowseComboBox = de->diffFileBrowseComboBox();
        if (diffBrowseComboBox->currentIndex() != section) {
            const bool blocked = diffBrowseComboBox->blockSignals(true);
            diffBrowseComboBox->setCurrentIndex(section);
            diffBrowseComboBox->blockSignals(blocked);
        }
    }
}

QAction *VCSBaseEditorWidget::createDescribeAction(const QString &change)
{
    QAction *a = new QAction(tr("Describe change %1").arg(change), 0);
    connect(a, SIGNAL(triggered()), this, SLOT(describe()));
    return a;
}

QAction *VCSBaseEditorWidget::createAnnotateAction(const QString &change, bool previous)
{
    // Use 'previous' format if desired and available, else default to standard.
    const QString &format =  previous && !d->m_annotatePreviousRevisionTextFormat.isEmpty() ?
                d->m_annotatePreviousRevisionTextFormat : d->m_annotateRevisionTextFormat;
    QAction *a = new QAction(format.arg(change), 0);
    a->setData(change);
    connect(a, SIGNAL(triggered()), this, SLOT(slotAnnotateRevision()));
    return a;
}

QAction *VCSBaseEditorWidget::createCopyRevisionAction(const QString &change)
{
    QAction *a = new QAction(d->m_copyRevisionTextFormat.arg(change), 0);
    a->setData(change);
    connect(a, SIGNAL(triggered()), this, SLOT(slotCopyRevision()));
    return a;
}

void VCSBaseEditorWidget::contextMenuEvent(QContextMenuEvent *e)
{
    QMenu *menu = createStandardContextMenu();
    // 'click on change-interaction'
    switch (d->m_parameters->type) {
    case LogOutput:
    case AnnotateOutput:
        d->m_currentChange = changeUnderCursor(cursorForPosition(e->pos()));
        if (!d->m_currentChange.isEmpty()) {
            switch (d->m_parameters->type) {
            case LogOutput: // Describe current / Annotate file of current
                menu->addSeparator();
                menu->addAction(createCopyRevisionAction(d->m_currentChange));
                menu->addAction(createDescribeAction(d->m_currentChange));
                if (d->m_fileLogAnnotateEnabled)
                    menu->addAction(createAnnotateAction(d->m_currentChange, false));
                break;
            case AnnotateOutput: { // Describe current / annotate previous
                    menu->addSeparator();
                    menu->addAction(createCopyRevisionAction(d->m_currentChange));
                    menu->addAction(createDescribeAction(d->m_currentChange));
                    const QStringList previousVersions = annotationPreviousVersions(d->m_currentChange);
                    if (!previousVersions.isEmpty()) {
                        menu->addSeparator();
                        foreach(const QString &pv, previousVersions)
                            menu->addAction(createAnnotateAction(pv, true));
                    } // has previous versions
                }
                break;
            default:
                break;
            }         // switch type
        }             // has current change
        break;
    case DiffOutput: {
        menu->addSeparator();
        connect(menu->addAction(tr("Send to CodePaster...")), SIGNAL(triggered()),
                this, SLOT(slotPaste()));
        menu->addSeparator();
        QAction *revertAction = menu->addAction(tr("Revert Chunk..."));
        const DiffChunk chunk = diffChunk(cursorForPosition(e->pos()));
        revertAction->setEnabled(canRevertDiffChunk(chunk));
        revertAction->setData(qVariantFromValue(chunk));
        connect(revertAction, SIGNAL(triggered()), this, SLOT(slotRevertDiffChunk()));
    }
        break;
    default:
        break;
    }
    menu->exec(e->globalPos());
    delete menu;
}

void VCSBaseEditorWidget::mouseMoveEvent(QMouseEvent *e)
{
    if (e->buttons()) {
        d->m_mouseDragging = true;
        TextEditor::BaseTextEditorWidget::mouseMoveEvent(e);
        return;
    }

    bool overrideCursor = false;
    Qt::CursorShape cursorShape;

    if (d->m_parameters->type == LogOutput || d->m_parameters->type == AnnotateOutput) {
        // Link emulation behaviour for 'click on change-interaction'
        QTextCursor cursor = cursorForPosition(e->pos());
        QString change = changeUnderCursor(cursor);
        if (!change.isEmpty()) {
            QTextEdit::ExtraSelection sel;
            sel.cursor = cursor;
            sel.cursor.select(QTextCursor::WordUnderCursor);
            sel.format.setFontUnderline(true);
            sel.format.setProperty(QTextFormat::UserProperty, change);
            setExtraSelections(OtherSelection, QList<QTextEdit::ExtraSelection>() << sel);
            overrideCursor = true;
            cursorShape = Qt::PointingHandCursor;
        }
    } else {
        setExtraSelections(OtherSelection, QList<QTextEdit::ExtraSelection>());
        overrideCursor = true;
        cursorShape = Qt::IBeamCursor;
    }
    TextEditor::BaseTextEditorWidget::mouseMoveEvent(e);

    if (overrideCursor)
        viewport()->setCursor(cursorShape);
}

void VCSBaseEditorWidget::mouseReleaseEvent(QMouseEvent *e)
{
    const bool wasDragging = d->m_mouseDragging;
    d->m_mouseDragging = false;
    if (!wasDragging && (d->m_parameters->type == LogOutput || d->m_parameters->type == AnnotateOutput)) {
        if (e->button() == Qt::LeftButton &&!(e->modifiers() & Qt::ShiftModifier)) {
            QTextCursor cursor = cursorForPosition(e->pos());
            d->m_currentChange = changeUnderCursor(cursor);
            if (!d->m_currentChange.isEmpty()) {
                describe();
                e->accept();
                return;
            }
        }
    }
    TextEditor::BaseTextEditorWidget::mouseReleaseEvent(e);
}

void VCSBaseEditorWidget::mouseDoubleClickEvent(QMouseEvent *e)
{
    if (d->m_parameters->type == DiffOutput) {
        if (e->button() == Qt::LeftButton &&!(e->modifiers() & Qt::ShiftModifier)) {
            QTextCursor cursor = cursorForPosition(e->pos());
            jumpToChangeFromDiff(cursor);
        }
    }
    TextEditor::BaseTextEditorWidget::mouseDoubleClickEvent(e);
}

void VCSBaseEditorWidget::keyPressEvent(QKeyEvent *e)
{
    // Do not intercept return in editable patches.
    if (d->m_parameters->type == DiffOutput && isReadOnly()
        && (e->key() == Qt::Key_Enter || e->key() == Qt::Key_Return)) {
        jumpToChangeFromDiff(textCursor());
        return;
    }
    BaseTextEditorWidget::keyPressEvent(e);
}

void VCSBaseEditorWidget::describe()
{
    if (VCSBase::Constants::Internal::debug)
        qDebug() << "VCSBaseEditor::describe" << d->m_currentChange;
    if (!d->m_currentChange.isEmpty())
        emit describeRequested(d->m_source, d->m_currentChange);
}

void VCSBaseEditorWidget::slotActivateAnnotation()
{
    // The annotation highlighting depends on contents (change number
    // set with assigned colors)
    if (d->m_parameters->type != AnnotateOutput)
        return;

    const QSet<QString> changes = annotationChanges();
    if (changes.isEmpty())
        return;
    if (VCSBase::Constants::Internal::debug)
        qDebug() << "VCSBaseEditor::slotActivateAnnotation(): #" << changes.size();

    disconnect(this, SIGNAL(textChanged()), this, SLOT(slotActivateAnnotation()));

    if (BaseAnnotationHighlighter *ah = qobject_cast<BaseAnnotationHighlighter *>(baseTextDocument()->syntaxHighlighter())) {
        ah->setChangeNumbers(changes);
        ah->rehighlight();
    } else {
        baseTextDocument()->setSyntaxHighlighter(createAnnotationHighlighter(changes));
    }
}

// Check for a change chunk "@@ -91,7 +95,7 @@" and return
// the modified line number (95).
// Note that git appends stuff after "  @@" (function names, etc.).
static inline bool checkChunkLine(const QString &line, int *modifiedLineNumber)
{
    if (!line.startsWith(QLatin1String("@@ ")))
        return false;
    const int endPos = line.indexOf(QLatin1String(" @@"), 3);
    if (endPos == -1)
        return false;
    // the first chunk range applies to the original file, the second one to
    // the modified file, the one we're interested int
    const int plusPos = line.indexOf(QLatin1Char('+'), 3);
    if (plusPos == -1 || plusPos > endPos)
        return false;
    const int lineNumberPos = plusPos + 1;
    const int commaPos = line.indexOf(QLatin1Char(','), lineNumberPos);
    if (commaPos == -1 || commaPos > endPos)
        return false;
    const QString lineNumberStr = line.mid(lineNumberPos, commaPos - lineNumberPos);
    bool ok;
    *modifiedLineNumber = lineNumberStr.toInt(&ok);
    return ok;
}

void VCSBaseEditorWidget::jumpToChangeFromDiff(QTextCursor cursor)
{
    int chunkStart = 0;
    int lineCount = -1;
    const QChar deletionIndicator = QLatin1Char('-');
    // find nearest change hunk
    QTextBlock block = cursor.block();
    if (TextEditor::BaseTextDocumentLayout::foldingIndent(block) <= 1)
        /* We are in a diff header, do not jump anywhere. DiffHighlighter sets the foldingIndent for us. */
        return;
    for ( ; block.isValid() ; block = block.previous()) {
        const QString line = block.text();
        if (checkChunkLine(line, &chunkStart)) {
            break;
        } else {
            if (!line.startsWith(deletionIndicator))
                ++lineCount;
        }
    }

    if (VCSBase::Constants::Internal::debug)
        qDebug() << "VCSBaseEditor::jumpToChangeFromDiff()1" << chunkStart << lineCount;

    if (chunkStart == -1 || lineCount < 0 || !block.isValid())
        return;

    // find the filename in previous line, map depot name back
    block = block.previous();
    if (!block.isValid())
        return;
    const QString fileName = fileNameFromDiffSpecification(block);

    const bool exists = fileName.isEmpty() ? false : QFile::exists(fileName);

    if (VCSBase::Constants::Internal::debug)
        qDebug() << "VCSBaseEditor::jumpToChangeFromDiff()2" << fileName << "ex=" << exists << "line" << chunkStart <<  lineCount;

    if (!exists)
        return;

    Core::EditorManager *em = Core::EditorManager::instance();
    Core::IEditor *ed = em->openEditor(fileName, QString(), Core::EditorManager::ModeSwitch);
    if (TextEditor::ITextEditor *editor = qobject_cast<TextEditor::ITextEditor *>(ed))
        editor->gotoLine(chunkStart + lineCount);
}

// cut out chunk and determine file name.
DiffChunk VCSBaseEditorWidget::diffChunk(QTextCursor cursor) const
{
    QTC_ASSERT(d->m_parameters->type == DiffOutput, return DiffChunk(); )
    DiffChunk rc;
    // Search back for start of chunk.
    QTextBlock block = cursor.block();
    QTextBlock next = block.next();
    if (next.isValid() && TextEditor::BaseTextDocumentLayout::foldingIndent(next) <= 1)
        /* We are in a diff header, not in a chunk! DiffHighlighter sets the foldingIndent for us. */
        return rc;

    int chunkStart = 0;
    for ( ; block.isValid() ; block = block.previous()) {
        if (checkChunkLine(block.text(), &chunkStart)) {
            break;
        }
    }
    if (!chunkStart || !block.isValid())
        return rc;
    rc.fileName = fileNameFromDiffSpecification(block);
    if (rc.fileName.isEmpty())
        return rc;
    // Concatenate chunk and convert
    QString unicode = block.text();
    if (!unicode.endsWith(QLatin1Char('\n'))) // Missing in case of hg.
        unicode.append(QLatin1Char('\n'));
    for (block = block.next() ; block.isValid() ; block = block.next()) {
        const QString line = block.text();
        if (checkChunkLine(line, &chunkStart)) {
            break;
        } else {
            unicode += line;
            unicode += QLatin1Char('\n');
        }
    }
    const QTextCodec *cd = textCodec();
    rc.chunk = cd ? cd->fromUnicode(unicode) : unicode.toLocal8Bit();
    return rc;
}

void VCSBaseEditorWidget::setPlainTextData(const QByteArray &data)
{
    if (data.size() > Core::EditorManager::maxTextFileSize()) {
        setPlainText(msgTextTooLarge(data.size()));
    } else {
        setPlainText(codec()->toUnicode(data));
    }
}

void VCSBaseEditorWidget::setFontSettings(const TextEditor::FontSettings &fs)
{
    TextEditor::BaseTextEditorWidget::setFontSettings(fs);
    if (d->m_parameters->type == DiffOutput) {
        if (DiffHighlighter *highlighter = qobject_cast<DiffHighlighter*>(baseTextDocument()->syntaxHighlighter())) {
            static QVector<QString> categories;
            if (categories.isEmpty()) {
                categories << QLatin1String(TextEditor::Constants::C_TEXT)
                           << QLatin1String(TextEditor::Constants::C_ADDED_LINE)
                           << QLatin1String(TextEditor::Constants::C_REMOVED_LINE)
                           << QLatin1String(TextEditor::Constants::C_DIFF_FILE)
                           << QLatin1String(TextEditor::Constants::C_DIFF_LOCATION);
            }
            highlighter->setFormats(fs.toTextCharFormats(categories));
            highlighter->rehighlight();
        }
    }
}

const VCSBaseEditorParameters *VCSBaseEditorWidget::findType(const VCSBaseEditorParameters *array,
                                                       int arraySize,
                                                       EditorContentType et)
{
    for (int i = 0; i < arraySize; i++)
        if (array[i].type == et)
            return array + i;
    return 0;
}

// Find the codec used for a file querying the editor.
static QTextCodec *findFileCodec(const QString &source)
{
    typedef QList<Core::IEditor *> EditorList;

    const EditorList editors = Core::EditorManager::instance()->editorsForFileName(source);
    if (!editors.empty()) {
        const EditorList::const_iterator ecend =  editors.constEnd();
        for (EditorList::const_iterator it = editors.constBegin(); it != ecend; ++it)
            if (const TextEditor::BaseTextEditor *be = qobject_cast<const TextEditor::BaseTextEditor *>(*it)) {
                QTextCodec *codec = be->editorWidget()->textCodec();
                if (VCSBase::Constants::Internal::debug)
                    qDebug() << Q_FUNC_INFO << source << codec->name();
                return codec;
            }
    }
    if (VCSBase::Constants::Internal::debug)
        qDebug() << Q_FUNC_INFO << source << "not found";
    return 0;
}

// Find the codec by checking the projects (root dir of project file)
static QTextCodec *findProjectCodec(const QString &dir)
{
    typedef  QList<ProjectExplorer::Project*> ProjectList;
    // Try to find a project under which file tree the file is.
    const ProjectExplorer::SessionManager *sm = ProjectExplorer::ProjectExplorerPlugin::instance()->session();
    const ProjectList projects = sm->projects();
    if (!projects.empty()) {
        const ProjectList::const_iterator pcend = projects.constEnd();
        for (ProjectList::const_iterator it = projects.constBegin(); it != pcend; ++it)
            if (const Core::IFile *file = (*it)->file())
                if (file->fileName().startsWith(dir)) {
                    QTextCodec *codec = (*it)->editorConfiguration()->textCodec();
                    if (VCSBase::Constants::Internal::debug)
                        qDebug() << Q_FUNC_INFO << dir << (*it)->displayName() << codec->name();
                    return codec;
                }
    }
    if (VCSBase::Constants::Internal::debug)
        qDebug() << Q_FUNC_INFO << dir << "not found";
    return 0;
}

QTextCodec *VCSBaseEditorWidget::getCodec(const QString &source)
{
    if (!source.isEmpty()) {
        // Check file
        const QFileInfo sourceFi(source);
        if (sourceFi.isFile())
            if (QTextCodec *fc = findFileCodec(source))
                return fc;
        // Find by project via directory
        if (QTextCodec *pc = findProjectCodec(sourceFi.isFile() ? sourceFi.absolutePath() : source))
            return pc;
    }
    QTextCodec *sys = QTextCodec::codecForLocale();
    if (VCSBase::Constants::Internal::debug)
        qDebug() << Q_FUNC_INFO << source << "defaulting to " << sys->name();
    return sys;
}

QTextCodec *VCSBaseEditorWidget::getCodec(const QString &workingDirectory, const QStringList &files)
{
    if (files.empty())
        return getCodec(workingDirectory);
    return getCodec(workingDirectory + QLatin1Char('/') + files.front());
}

VCSBaseEditorWidget *VCSBaseEditorWidget::getVcsBaseEditor(const Core::IEditor *editor)
{
    if (const TextEditor::BaseTextEditor *be = qobject_cast<const TextEditor::BaseTextEditor *>(editor))
        return qobject_cast<VCSBaseEditorWidget *>(be->editorWidget());
    return 0;
}

// Return line number of current editor if it matches.
int VCSBaseEditorWidget::lineNumberOfCurrentEditor(const QString &currentFile)
{
    Core::IEditor *ed = Core::EditorManager::instance()->currentEditor();
    if (!ed)
        return -1;
    if (!currentFile.isEmpty()) {
        const Core::IFile *ifile  = ed->file();
        if (!ifile || ifile->fileName() != currentFile)
            return -1;
    }
    const TextEditor::BaseTextEditor *eda = qobject_cast<const TextEditor::BaseTextEditor *>(ed);
    if (!eda)
        return -1;
    return eda->currentLine();
}

bool VCSBaseEditorWidget::gotoLineOfEditor(Core::IEditor *e, int lineNumber)
{
    if (lineNumber >= 0 && e) {
        if (TextEditor::BaseTextEditor *be = qobject_cast<TextEditor::BaseTextEditor*>(e)) {
            be->gotoLine(lineNumber);
            return true;
        }
    }
    return false;
}

// Return source file or directory string depending on parameters
// ('git diff XX' -> 'XX' , 'git diff XX file' -> 'XX/file').
QString VCSBaseEditorWidget::getSource(const QString &workingDirectory,
                                 const QString &fileName)
{
    if (fileName.isEmpty())
        return workingDirectory;

    QString rc = workingDirectory;
    const QChar slash = QLatin1Char('/');
    if (!rc.isEmpty() && !(rc.endsWith(slash) || rc.endsWith(QLatin1Char('\\'))))
        rc += slash;
    rc += fileName;
    return rc;
}

QString VCSBaseEditorWidget::getSource(const QString &workingDirectory,
                                 const QStringList &fileNames)
{
    return fileNames.size() == 1 ?
            getSource(workingDirectory, fileNames.front()) :
            workingDirectory;
}

QString VCSBaseEditorWidget::getTitleId(const QString &workingDirectory,
                                  const QStringList &fileNames,
                                  const QString &revision)
{
    QString rc;
    switch (fileNames.size()) {
    case 0:
        rc = workingDirectory;
        break;
    case 1:
        rc = fileNames.front();
        break;
    default:
        rc = fileNames.join(QLatin1String(", "));
        break;
    }
    if (!revision.isEmpty()) {
        rc += QLatin1Char(':');
        rc += revision;
    }
    return rc;
}

bool VCSBaseEditorWidget::setConfigurationWidget(QWidget *w)
{
    if (!d->m_editor || d->m_configurationWidget)
        return false;

    d->m_configurationWidget = w;
    d->m_editor->insertExtraToolBarWidget(TextEditor::BaseTextEditor::Right, w);

    return true;
}

QWidget *VCSBaseEditorWidget::configurationWidget() const
{
    return d->m_configurationWidget;
}

// Find the complete file from a diff relative specification.
QString VCSBaseEditorWidget::findDiffFile(const QString &f,
                                          Core::IVersionControl *control /* = 0 */) const
{
    // Check if file is absolute
    const QFileInfo in(f);
    if (in.isAbsolute())
        return in.isFile() ? f : QString();

    // 1) Try base dir
    const QChar slash = QLatin1Char('/');
    if (!d->m_diffBaseDirectory.isEmpty()) {
        const QFileInfo baseFileInfo(d->m_diffBaseDirectory + slash + f);
        if (baseFileInfo.isFile())
            return baseFileInfo.absoluteFilePath();
    }
    // 2) Try in source (which can be file or directory)
    if (!source().isEmpty()) {
        const QFileInfo sourceInfo(source());
        const QString sourceDir = sourceInfo.isDir() ? sourceInfo.absoluteFilePath()
                                                     : sourceInfo.absolutePath();
        const QFileInfo sourceFileInfo(sourceDir + slash + f);
        if (sourceFileInfo.isFile())
            return sourceFileInfo.absoluteFilePath();

        QString topLevel;
        if (control && control->managesDirectory(sourceDir, &topLevel)) {
            const QFileInfo topLevelFileInfo(topLevel + slash + f);
            if (topLevelFileInfo.isFile())
                return topLevelFileInfo.absoluteFilePath();
        }
    }

    // 3) Try working directory
    if (in.isFile())
        return in.absoluteFilePath();

    return QString();
}

void VCSBaseEditorWidget::slotAnnotateRevision()
{
    if (const QAction *a = qobject_cast<const QAction *>(sender()))
        emit annotateRevisionRequested(source(), a->data().toString(),
                                       editor()->currentLine());
}

void VCSBaseEditorWidget::slotCopyRevision()
{
    QApplication::clipboard()->setText(d->m_currentChange);
}

QStringList VCSBaseEditorWidget::annotationPreviousVersions(const QString &) const
{
    return QStringList();
}

void VCSBaseEditorWidget::slotPaste()
{
    // Retrieve service by soft dependency.
    QObject *pasteService =
            ExtensionSystem::PluginManager::instance()
                ->getObjectByClassName("CodePaster::CodePasterService");
    if (pasteService) {
        QMetaObject::invokeMethod(pasteService, "postCurrentEditor");
    } else {
        QMessageBox::information(this, tr("Unable to Paste"),
                                 tr("Code pasting services are not available."));
    }
}

bool VCSBaseEditorWidget::isRevertDiffChunkEnabled() const
{
    return d->m_revertChunkEnabled;
}

void VCSBaseEditorWidget::setRevertDiffChunkEnabled(bool e)
{
    d->m_revertChunkEnabled = e;
}

bool VCSBaseEditorWidget::canRevertDiffChunk(const DiffChunk &dc) const
{
    if (!isRevertDiffChunkEnabled() || !dc.isValid())
        return false;
    const QFileInfo fi(dc.fileName);
    // Default implementation using patch.exe relies on absolute paths.
    return fi.isFile() && fi.isAbsolute() && fi.isWritable();
}

// Default implementation of revert: Revert a chunk by piping it into patch
// with '-R', assuming we got absolute paths from the VCS plugins.
bool VCSBaseEditorWidget::revertDiffChunk(const DiffChunk &dc) const
{
    return VCSBasePlugin::runPatch(dc.asPatch(), QString(), 0, true);
}

void VCSBaseEditorWidget::slotRevertDiffChunk()
{
    const QAction *a = qobject_cast<QAction *>(sender());
    QTC_ASSERT(a, return ; )
    const DiffChunk chunk = qvariant_cast<DiffChunk>(a->data());
    if (QMessageBox::No == QMessageBox::question(this, tr("Revert Chunk"),
                                                  tr("Would you like to revert the chunk?"),
                                                  QMessageBox::Yes|QMessageBox::No))
        return;

    if (revertDiffChunk(chunk))
        emit diffChunkReverted(chunk);
}

// Tagging of editors for re-use.
QString VCSBaseEditorWidget::editorTag(EditorContentType t,
                                       const QString &workingDirectory,
                                       const QStringList &files,
                                       const QString &revision)
{
    const QChar colon = QLatin1Char(':');
    QString rc = QString::number(t);
    rc += colon;
    if (!revision.isEmpty()) {
        rc += revision;
        rc += colon;
    }
    rc += workingDirectory;
    if (!files.isEmpty()) {
        rc += colon;
        rc += files.join(QString(colon));
    }
    return rc;
}

static const char tagPropertyC[] = "_q_VCSBaseEditorTag";

void VCSBaseEditorWidget::tagEditor(Core::IEditor *e, const QString &tag)
{
    e->setProperty(tagPropertyC, QVariant(tag));
}

Core::IEditor* VCSBaseEditorWidget::locateEditorByTag(const QString &tag)
{
    Core::IEditor *rc = 0;
    foreach (Core::IEditor *ed, Core::EditorManager::instance()->openedEditors()) {
        const QVariant tagPropertyValue = ed->property(tagPropertyC);
        if (tagPropertyValue.type() == QVariant::String && tagPropertyValue.toString() == tag) {
            rc = ed;
            break;
        }
    }
    if (VCSBase::Constants::Internal::debug)
        qDebug() << "locateEditorByTag " << tag << rc;
    return rc;
}

} // namespace VCSBase

#include "vcsbaseeditor.moc"
