* Use the term "version control" instead of "revision control" to be consistent with the naming in kdevplatform.

* Renamed VersionControlPlugin to KVersionControlPlugin so that the interface can be moved out of Dolphin.

svn path=/trunk/KDE/kdebase/apps/; revision=1011058

1 files changed, 326 insertions, 0 deletions

diff --git a/src/versioncontrolobserver.cpp b/src/versioncontrolobserver.cpp
new file mode 100644
index 000000000..03bba9f02
--- /dev/null
+++ b/src/versioncontrolobserver.cpp
@@ -0,0 +1,326 @@
+/***************************************************************************
+ *   Copyright (C) 2009 by Peter Penz <[email protected]>                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
+ ***************************************************************************/
+
+#include "versioncontrolobserver.h"
+
+#include "dolphinmodel.h"
+#include "kversioncontrolplugin.h"
+
+#include <kdirlister.h>
+#include <klocale.h>
+
+#include <QAbstractProxyModel>
+#include <QAbstractItemView>
+#include <QMutexLocker>
+#include <QTimer>
+
+/**
+ * The performance of updating the version state of items depends
+ * on the used plugin. To prevent that Dolphin gets blocked by a
+ * slow plugin, the updating is delegated to a thread.
+ */
+class UpdateItemStatesThread : public QThread
+{
+public:
+    UpdateItemStatesThread(QObject* parent, QMutex* pluginMutex);
+    void setData(KVersionControlPlugin* plugin,
+                 const QList<VersionControlObserver::ItemState>& itemStates);
+    QList<VersionControlObserver::ItemState> itemStates() const;
+    bool retrievedItems() const;
+
+protected:
+    virtual void run();
+    
+private:
+    bool m_retrievedItems;
+    KVersionControlPlugin* m_plugin;
+    QMutex* m_pluginMutex;
+    QList<VersionControlObserver::ItemState> m_itemStates;
+};
+
+UpdateItemStatesThread::UpdateItemStatesThread(QObject* parent, QMutex* pluginMutex) :
+    QThread(parent),
+    m_retrievedItems(false),
+    m_pluginMutex(pluginMutex),
+    m_itemStates()
+{
+}
+
+void UpdateItemStatesThread::setData(KVersionControlPlugin* plugin,
+                                     const QList<VersionControlObserver::ItemState>& itemStates)
+{
+    m_plugin = plugin;
+    m_itemStates = itemStates;
+}
+
+void UpdateItemStatesThread::run()
+{
+    Q_ASSERT(!m_itemStates.isEmpty());
+    Q_ASSERT(m_plugin != 0);
+
+    // The items from m_itemStates may be located in different directory levels. The version
+    // plugin requires the root directory for KVersionControlPlugin::beginRetrieval(). Instead
+    // of doing an expensive search, we utilize the knowledge of the implementation of
+    // VersionControlObserver::addDirectory() to be sure that the last item contains the root.
+    const QString directory = m_itemStates.last().item.url().directory(KUrl::AppendTrailingSlash);
+
+    QMutexLocker locker(m_pluginMutex);
+    m_retrievedItems = false;
+    if (m_plugin->beginRetrieval(directory)) {
+        const int count = m_itemStates.count();
+        for (int i = 0; i < count; ++i) {
+            m_itemStates[i].version = m_plugin->versionState(m_itemStates[i].item);
+        }
+        m_plugin->endRetrieval();
+        m_retrievedItems = true;
+    }
+}
+
+QList<VersionControlObserver::ItemState> UpdateItemStatesThread::itemStates() const
+{
+    return m_itemStates;
+}
+
+bool UpdateItemStatesThread::retrievedItems() const
+{
+    return m_retrievedItems;
+}
+
+// ------------------------------------------------------------------------------------------------
+
+VersionControlObserver::VersionControlObserver(QAbstractItemView* view) :
+    QObject(view),
+    m_pendingItemStatesUpdate(false),
+    m_versionedDirectory(false),
+    m_silentUpdate(false),
+    m_view(view),
+    m_dirLister(0),
+    m_dolphinModel(0),
+    m_dirVerificationTimer(0),
+    m_pluginMutex(QMutex::Recursive),
+    m_plugin(0),
+    m_updateItemStatesThread(0)
+{
+    Q_ASSERT(view != 0);
+
+    QAbstractProxyModel* proxyModel = qobject_cast<QAbstractProxyModel*>(view->model());
+    m_dolphinModel = (proxyModel == 0) ?
+                     qobject_cast<DolphinModel*>(view->model()) :
+                     qobject_cast<DolphinModel*>(proxyModel->sourceModel());
+    if (m_dolphinModel != 0) {
+        m_dirLister = m_dolphinModel->dirLister();
+        connect(m_dirLister, SIGNAL(completed()),
+                this, SLOT(delayedDirectoryVerification()));
+ 
+        // The verification timer specifies the timeout until the shown directory
+        // is checked whether it is versioned. Per default it is assumed that users
+        // don't iterate through versioned directories and a high timeout is used
+        // The timeout will be decreased as soon as a versioned directory has been
+        // found (see verifyDirectory()).
+        m_dirVerificationTimer = new QTimer(this);
+        m_dirVerificationTimer->setSingleShot(true);
+        m_dirVerificationTimer->setInterval(500);
+        connect(m_dirVerificationTimer, SIGNAL(timeout()),
+                this, SLOT(verifyDirectory()));
+    }
+}
+
+VersionControlObserver::~VersionControlObserver()
+{
+    if (m_updateItemStatesThread != 0) {
+        m_updateItemStatesThread->terminate();
+        m_updateItemStatesThread->wait();
+    }
+    delete m_plugin;
+    m_plugin = 0;
+}
+
+QList<QAction*> VersionControlObserver::contextMenuActions(const KFileItemList& items) const
+{
+    if (m_dolphinModel->hasVersionData() && (m_plugin != 0)) {
+        QMutexLocker locker(&m_pluginMutex);
+        return m_plugin->contextMenuActions(items);
+    }
+    return QList<QAction*>();
+}
+
+QList<QAction*> VersionControlObserver::contextMenuActions(const QString& directory) const
+{
+    if (m_dolphinModel->hasVersionData() && (m_plugin != 0)) {
+        QMutexLocker locker(&m_pluginMutex);
+        return m_plugin->contextMenuActions(directory);
+    }
+
+    return QList<QAction*>();
+}
+
+void VersionControlObserver::delayedDirectoryVerification()
+{
+    m_silentUpdate = false;
+    m_dirVerificationTimer->start();
+}
+
+void VersionControlObserver::silentDirectoryVerification()
+{
+    m_silentUpdate = true;
+    m_dirVerificationTimer->start();
+}
+
+void VersionControlObserver::verifyDirectory()
+{
+    KUrl versionControlUrl = m_dirLister->url();
+    if (!versionControlUrl.isLocalFile()) {
+        return;
+    }
+
+    if (m_plugin == 0) {
+        // TODO: just for testing purposes. A plugin approach will be used later.
+        m_plugin = new SubversionPlugin();
+        connect(m_plugin, SIGNAL(infoMessage(const QString&)),
+                this, SIGNAL(infoMessage(const QString&)));
+        connect(m_plugin, SIGNAL(errorMessage(const QString&)),
+                this, SIGNAL(errorMessage(const QString&)));
+        connect(m_plugin, SIGNAL(operationCompletedMessage(const QString&)),
+                this, SIGNAL(operationCompletedMessage(const QString&)));
+    }
+
+    versionControlUrl.addPath(m_plugin->fileName());
+    const KFileItem item = m_dirLister->findByUrl(versionControlUrl);
+
+    bool foundVersionInfo = !item.isNull();
+    if (!foundVersionInfo && m_versionedDirectory) {
+        // Version control systems like Git provide the version information
+        // file only in the root directory. Check whether the version information file can
+        // be found in one of the parent directories.
+
+        // TODO...
+    }
+
+    if (foundVersionInfo) {
+        if (!m_versionedDirectory) {
+            m_versionedDirectory = true;
+
+            // The directory is versioned. Assume that the user will further browse through
+            // versioned directories and decrease the verification timer.
+            m_dirVerificationTimer->setInterval(100);
+            connect(m_dirLister, SIGNAL(refreshItems(const QList<QPair<KFileItem,KFileItem>>&)),
+                    this, SLOT(delayedDirectoryVerification()));
+            connect(m_dirLister, SIGNAL(newItems(const KFileItemList&)),
+                    this, SLOT(delayedDirectoryVerification()));
+            connect(m_plugin, SIGNAL(versionStatesChanged()),
+                    this, SLOT(silentDirectoryVerification()));
+        }
+        updateItemStates();
+    } else if (m_versionedDirectory) {
+        m_versionedDirectory = false;
+
+        // The directory is not versioned. Reset the verification timer to a higher
+        // value, so that browsing through non-versioned directories is not slown down
+        // by an immediate verification.
+        m_dirVerificationTimer->setInterval(500);
+        disconnect(m_dirLister, SIGNAL(refreshItems(const QList<QPair<KFileItem,KFileItem>>&)),
+                   this, SLOT(delayedDirectoryVerification()));
+        disconnect(m_dirLister, SIGNAL(newItems(const KFileItemList&)),
+                   this, SLOT(delayedDirectoryVerification()));
+        disconnect(m_plugin, SIGNAL(versionStatesChanged()),
+                   this, SLOT(silentDirectoryVerification()));
+    }
+}
+
+void VersionControlObserver::applyUpdatedItemStates()
+{
+    if (!m_updateItemStatesThread->retrievedItems()) {
+        // ignore m_silentUpdate for an error message
+        emit errorMessage(i18nc("@info:status", "Update of version information failed."));
+        return;
+    }
+
+    // QAbstractItemModel::setData() triggers a bottleneck in combination with QListView
+    // (a detailed description of the root cause is given in the class KFilePreviewGenerator
+    // from kdelibs). To bypass this bottleneck, the signals of the model are temporary blocked.
+    // This works as the update of the data does not require a relayout of the views used in Dolphin.
+    const bool signalsBlocked = m_dolphinModel->signalsBlocked();
+    m_dolphinModel->blockSignals(true);
+
+    const QList<ItemState> itemStates = m_updateItemStatesThread->itemStates();
+    foreach (const ItemState& itemState, itemStates) {
+        m_dolphinModel->setData(itemState.index,
+                                QVariant(static_cast<int>(itemState.version)),
+                                Qt::DecorationRole);
+    }
+
+    m_dolphinModel->blockSignals(signalsBlocked);
+    m_view->viewport()->repaint();
+
+    if (!m_silentUpdate) {
+        // Using an empty message results in clearing the previously shown information message and showing
+        // the default status bar information. This is useful as the user already gets feedback that the
+        // operation has been completed because of the icon emblems.
+        emit operationCompletedMessage(QString());
+    }
+    
+    if (m_pendingItemStatesUpdate) {
+        m_pendingItemStatesUpdate = false;
+        updateItemStates();
+    }
+}
+
+void VersionControlObserver::updateItemStates()
+{
+    Q_ASSERT(m_plugin != 0);
+    if (m_updateItemStatesThread == 0) {
+        m_updateItemStatesThread = new UpdateItemStatesThread(this, &m_pluginMutex);
+        connect(m_updateItemStatesThread, SIGNAL(finished()),
+                this, SLOT(applyUpdatedItemStates()));
+    }
+    if (m_updateItemStatesThread->isRunning()) {
+        // An update is currently ongoing. Wait until the thread has finished
+        // the update (see applyUpdatedItemStates()).
+        m_pendingItemStatesUpdate = true;
+        return;
+    }
+    
+    QList<ItemState> itemStates;
+    addDirectory(QModelIndex(), itemStates);
+    if (!itemStates.isEmpty()) {
+        if (!m_silentUpdate) {
+            emit infoMessage(i18nc("@info:status", "Updating version information..."));
+        }
+        m_updateItemStatesThread->setData(m_plugin, itemStates);
+        m_updateItemStatesThread->start(); // applyUpdatedItemStates() is called when finished
+    }
+}
+
+void VersionControlObserver::addDirectory(const QModelIndex& parentIndex, QList<ItemState>& itemStates)
+{
+    const int rowCount = m_dolphinModel->rowCount(parentIndex);
+    for (int row = 0; row < rowCount; ++row) {
+        const QModelIndex index = m_dolphinModel->index(row, DolphinModel::Version, parentIndex);
+        addDirectory(index, itemStates);
+        
+        ItemState itemState;
+        itemState.index = index;
+        itemState.item = m_dolphinModel->itemForIndex(index);
+        itemState.version = KVersionControlPlugin::UnversionedVersion;
+
+        itemStates.append(itemState);
+    }
+}
+
+#include "versioncontrolobserver.moc"