1 files changed, 175 insertions, 0 deletions

diff --git a/common/entitystorage.h b/common/entitystorage.h
new file mode 100644
index 0000000..6a41e0e
--- /dev/null
+++ b/common/entitystorage.h
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2014 Christian Mollekopf <chrigi_1@fastmail.fm>
+ *
+ *   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.
+ */
+#pragma once
+
+#include "clientapi.h"
+
+#include <QByteArray>
+
+#include "domainadaptor.h"
+#include "entitybuffer.h"
+#include "log.h"
+#include "storage.h"
+#include "resultset.h"
+
+/**
+ * Wraps storage, entity adaptor factory and indexes into one.
+ */
+template <typename DomainType>
+class EntityStorage
+{
+
+public:
+    EntityStorage(const QByteArray &instanceIdentifier, const DomainTypeAdaptorFactoryInterface::Ptr &adaptorFactory)
+        : mResourceInstanceIdentifier(instanceIdentifier),
+        mDomainTypeAdaptorFactory(adaptorFactory)
+    {
+
+    }
+
+private:
+    static void scan(const QSharedPointer<Akonadi2::Storage> &storage, const QByteArray &key, std::function<bool(const QByteArray &key, const Akonadi2::Entity &entity)> callback)
+    {
+        storage->scan(key, [=](void *keyValue, int keySize, void *dataValue, int dataSize) -> bool {
+            //Skip internals
+            if (Akonadi2::Storage::isInternalKey(keyValue, keySize)) {
+                return true;
+            }
+
+            //Extract buffers
+            Akonadi2::EntityBuffer buffer(dataValue, dataSize);
+
+            //FIXME implement buffer.isValid()
+            // const auto resourceBuffer = Akonadi2::EntityBuffer::readBuffer<DummyEvent>(buffer.entity().resource());
+            // const auto localBuffer = Akonadi2::EntityBuffer::readBuffer<Akonadi2::ApplicationDomain::Buffer::Event>(buffer.entity().local());
+            // const auto metadataBuffer = Akonadi2::EntityBuffer::readBuffer<Akonadi2::Metadata>(buffer.entity().metadata());
+
+            // if ((!resourceBuffer && !localBuffer) || !metadataBuffer) {
+            //     qWarning() << "invalid buffer " << QByteArray::fromRawData(static_cast<char*>(keyValue), keySize);
+            //     return true;
+            // }
+            return callback(QByteArray::fromRawData(static_cast<char*>(keyValue), keySize), buffer.entity());
+        },
+        [](const Akonadi2::Storage::Error &error) {
+            qWarning() << "Error during query: " << error.message;
+        });
+    }
+
+    static void readValue(const QSharedPointer<Akonadi2::Storage> &storage, const QByteArray &key, const std::function<void(const typename DomainType::Ptr &)> &resultCallback, const DomainTypeAdaptorFactoryInterface::Ptr &adaptorFactory, const QByteArray &instanceIdentifier)
+    {
+        scan(storage, key, [=](const QByteArray &key, const Akonadi2::Entity &entity) {
+            const auto metadataBuffer = Akonadi2::EntityBuffer::readBuffer<Akonadi2::Metadata>(entity.metadata());
+            qint64 revision = metadataBuffer ? metadataBuffer->revision() : -1;
+            //This only works for a 1:1 mapping of resource to domain types.
+            //Not i.e. for tags that are stored as flags in each entity of an imap store.
+            //additional properties that don't have a 1:1 mapping (such as separately stored tags),
+            //could be added to the adaptor
+            auto domainObject = QSharedPointer<DomainType>::create(instanceIdentifier, key, revision, adaptorFactory->createAdaptor(entity));
+            resultCallback(domainObject);
+            return true;
+        });
+    }
+
+    static ResultSet fullScan(const QSharedPointer<Akonadi2::Storage> &storage)
+    {
+        //TODO use a result set with an iterator, to read values on demand
+        QVector<QByteArray> keys;
+        scan(storage, QByteArray(), [=, &keys](const QByteArray &key, const Akonadi2::Entity &) {
+            keys << key;
+            return true;
+        });
+        Trace() << "Full scan found " << keys.size() << " results";
+        return ResultSet(keys);
+    }
+
+    static ResultSet filteredSet(const ResultSet &resultSet, const std::function<bool(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &domainObject)> &filter, const QSharedPointer<Akonadi2::Storage> &storage, const DomainTypeAdaptorFactoryInterface::Ptr &adaptorFactory, qint64 baseRevision, qint64 topRevision, const QByteArray &instanceIdentifier)
+    {
+        auto resultSetPtr = QSharedPointer<ResultSet>::create(resultSet);
+
+        //Read through the source values and return whatever matches the filter
+        std::function<bool(std::function<void(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &)>)> generator = [resultSetPtr, storage, adaptorFactory, filter, instanceIdentifier](std::function<void(const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &)> callback) -> bool {
+            while (resultSetPtr->next()) {
+                readValue(storage, resultSetPtr->id(), [filter, callback](const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &domainObject) {
+                    if (filter(domainObject)) {
+                        callback(domainObject);
+                    }
+                }, adaptorFactory, instanceIdentifier);
+            }
+            return false;
+        };
+        return ResultSet(generator);
+    }
+
+    static ResultSet getResultSet(const Akonadi2::Query &query, const QSharedPointer<Akonadi2::Storage> &storage, const DomainTypeAdaptorFactoryInterface::Ptr &adaptorFactory, const QByteArray &resourceInstanceIdentifier, qint64 baseRevision, qint64 topRevision)
+    {
+        QSet<QByteArray> appliedFilters;
+        ResultSet resultSet = Akonadi2::ApplicationDomain::TypeImplementation<DomainType>::queryIndexes(query, resourceInstanceIdentifier, appliedFilters, qMakePair(baseRevision, topRevision));
+        const auto remainingFilters = query.propertyFilter.keys().toSet() - appliedFilters;
+
+        //We do a full scan if there were no indexes available to create the initial set.
+        if (appliedFilters.isEmpty()) {
+            resultSet = fullScan(storage);
+        }
+
+        auto filter = [remainingFilters, query, baseRevision, topRevision](const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &domainObject) -> bool {
+            if (topRevision > 0) {
+                Trace() << "filtering by revision " << domainObject->revision();
+                if (domainObject->revision() < baseRevision || domainObject->revision() > topRevision) {
+                    return false;
+                }
+            }
+            for (const auto &filterProperty : remainingFilters) {
+                //TODO implement other comparison operators than equality
+                if (domainObject->getProperty(filterProperty) != query.propertyFilter.value(filterProperty)) {
+                    return false;
+                }
+            }
+            return true;
+        };
+
+        return filteredSet(resultSet, filter, storage, adaptorFactory, baseRevision, topRevision, resourceInstanceIdentifier);
+    }
+
+public:
+
+    void read(const Akonadi2::Query &query, const QPair<qint64, qint64> &revisionRange, const QSharedPointer<Akonadi2::ResultProvider<typename DomainType::Ptr> > &resultProvider)
+    {
+        auto storage = QSharedPointer<Akonadi2::Storage>::create(Akonadi2::Store::storageLocation(), mResourceInstanceIdentifier);
+        storage->setDefaultErrorHandler([](const Akonadi2::Storage::Error &error) {
+            Warning() << "Error during query: " << error.store << error.message;
+        });
+
+        storage->startTransaction(Akonadi2::Storage::ReadOnly);
+        //TODO start transaction on indexes as well
+
+        Log() << "Querying" << revisionRange.first << revisionRange.second;
+        auto resultSet = getResultSet(query, storage, mDomainTypeAdaptorFactory, mResourceInstanceIdentifier, revisionRange.first, revisionRange.second);
+        auto resultCallback = std::bind(&Akonadi2::ResultProvider<typename DomainType::Ptr>::add, resultProvider, std::placeholders::_1);
+        while(resultSet.next([resultCallback](const Akonadi2::ApplicationDomain::ApplicationDomainType::Ptr &value) -> bool {
+            resultCallback(Akonadi2::ApplicationDomain::ApplicationDomainType::getInMemoryRepresentation<DomainType>(*value));
+            return true;
+        })){};
+        //TODO replay removals and modifications
+        storage->abortTransaction();
+    }
+
+private:
+    DomainTypeAdaptorFactoryInterface::Ptr mDomainTypeAdaptorFactory;
+    QByteArray mResourceInstanceIdentifier;
+};