1 files changed, 102 insertions, 0 deletions

diff --git a/common/changereplay.cpp b/common/changereplay.cpp
new file mode 100644
index 0000000..2447b6e
--- /dev/null
+++ b/common/changereplay.cpp
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2016 Christian Mollekopf <mollekopf@kolabsys.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) version 3, or any
+ * later version accepted by the membership of KDE e.V. (or its
+ * successor approved by the membership of KDE e.V.), which shall
+ * act as a proxy defined in Section 6 of version 3 of the license.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "changereplay.h"
+
+#include "entitybuffer.h"
+#include "log.h"
+#include "definitions.h"
+#include "bufferutils.h"
+
+using namespace Sink;
+
+#undef DEBUG_AREA
+#define DEBUG_AREA "resource.changereplay"
+
+ChangeReplay::ChangeReplay(const QByteArray &resourceName)
+    : mStorage(storageLocation(), resourceName, Storage::ReadOnly), mChangeReplayStore(storageLocation(), resourceName + ".changereplay", Storage::ReadWrite)
+{
+    Trace() << "Created change replay: " << resourceName;
+}
+
+qint64 ChangeReplay::getLastReplayedRevision()
+{
+    qint64 lastReplayedRevision = 0;
+    auto replayStoreTransaction = mChangeReplayStore.createTransaction(Storage::ReadOnly);
+    replayStoreTransaction.openDatabase().scan("lastReplayedRevision",
+        [&lastReplayedRevision](const QByteArray &key, const QByteArray &value) -> bool {
+            lastReplayedRevision = value.toLongLong();
+            return false;
+        },
+        [](const Storage::Error &) {});
+    return lastReplayedRevision;
+}
+
+bool ChangeReplay::allChangesReplayed()
+{
+    const qint64 topRevision = Storage::maxRevision(mStorage.createTransaction(Storage::ReadOnly, [](const Sink::Storage::Error &error) {
+        Warning() << error.message;
+    }));
+    const qint64 lastReplayedRevision = getLastReplayedRevision();
+    Trace() << "All changes replayed " << topRevision << lastReplayedRevision;
+    return (lastReplayedRevision >= topRevision);
+}
+
+void ChangeReplay::revisionChanged()
+{
+    auto mainStoreTransaction = mStorage.createTransaction(Storage::ReadOnly, [](const Sink::Storage::Error &error) {
+        Warning() << error.message;
+    });
+    auto replayStoreTransaction = mChangeReplayStore.createTransaction(Storage::ReadWrite, [](const Sink::Storage::Error &error) {
+        Warning() << error.message;
+    });
+    qint64 lastReplayedRevision = 1;
+    replayStoreTransaction.openDatabase().scan("lastReplayedRevision",
+        [&lastReplayedRevision](const QByteArray &key, const QByteArray &value) -> bool {
+            lastReplayedRevision = value.toLongLong();
+            return false;
+        },
+        [](const Storage::Error &) {});
+    const qint64 topRevision = Storage::maxRevision(mainStoreTransaction);
+
+    Trace() << "Changereplay from " << lastReplayedRevision << " to " << topRevision;
+    if (lastReplayedRevision <= topRevision) {
+        qint64 revision = lastReplayedRevision;
+        for (; revision <= topRevision; revision++) {
+            const auto uid = Storage::getUidFromRevision(mainStoreTransaction, revision);
+            const auto type = Storage::getTypeFromRevision(mainStoreTransaction, revision);
+            const auto key = Storage::assembleKey(uid, revision);
+            Storage::mainDatabase(mainStoreTransaction, type)
+                .scan(key,
+                    [&lastReplayedRevision, type, this](const QByteArray &key, const QByteArray &value) -> bool {
+                        replay(type, key, value).exec();
+                        // TODO make for loop async, and pass to async replay function together with type
+                        Trace() << "Replaying " << key;
+                        return false;
+                    },
+                    [key](const Storage::Error &) { ErrorMsg() << "Failed to replay change " << key; });
+        }
+        revision--;
+        replayStoreTransaction.openDatabase().write("lastReplayedRevision", QByteArray::number(revision));
+        replayStoreTransaction.commit();
+        Trace() << "Replayed until " << revision;
+    }
+    emit changesReplayed();
+}
+