a basically-working Pipeline implementation

still a skeleton rather than a full body with flesh and blood, but
it is getting there!

1 files changed, 184 insertions, 15 deletions

diff --git a/common/pipeline.cpp b/common/pipeline.cpp
index 41def7c..5606c30 100644
--- a/common/pipeline.cpp
+++ b/common/pipeline.cpp
@@ -20,7 +20,9 @@
 
 #include "pipeline.h"
 
+#include <QByteArray>
 #include <QStandardPaths>
+#include <QVector>
 
 namespace Akonadi2
 {
@@ -28,47 +30,214 @@ namespace Akonadi2
 class Pipeline::Private
 {
 public:
-    Private(const QString &storageName)
-        : storage(QStandardPaths::writableLocation(QStandardPaths::QStandardPaths::GenericDataLocation) + "/akonadi2", storageName, Akonadi2::Storage::ReadWrite)
+    Private(const QString &resourceName)
+        : storage(QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + "/akonadi2/storage", resourceName),
+          stepScheduled(false)
     {
-
     }
 
-    Akonadi2::Storage storage;
+    Storage storage;
+    QVector<PipelineFilter *> nullPipeline;
+    QVector<PipelineFilter *> newPipeline;
+    QVector<PipelineFilter *> modifiedPipeline;
+    QVector<PipelineFilter *> deletedPipeline;
+    QVector<PipelineState> activePipelines;
+    bool stepScheduled;
 };
 
-Pipeline::Pipeline(const QString &storageName)
-    : d(new Private(storageName))
+Pipeline::Pipeline(const QString &resourceName, QObject *parent)
+    : QObject(parent),
+      d(new Private(resourceName))
 {
 }
 
 Pipeline::~Pipeline()
 {
+    delete d;
 }
 
-Storage &Pipeline::storage()
+Storage &Pipeline::storage() const
 {
     return d->storage;
 }
 
-void Pipeline::null(uint messageId, const char *key, size_t keySize, const char *buffer, size_t bufferSize)
+void Pipeline::null()
+{
+    //TODO: is there really any need for the null pipeline? if so, it should be doing something ;)
+    PipelineState state(this, NullPipeline, QByteArray(), d->nullPipeline);
+    d->activePipelines << state;
+    state.step();
+}
+
+void Pipeline::newEntity(const QByteArray &key, flatbuffers::FlatBufferBuilder &entity)
+{
+    PipelineState state(this, NewPipeline, key, d->newPipeline);
+    d->activePipelines << state;
+    state.step();
+}
+
+void Pipeline::modifiedEntity(const QByteArray &key, flatbuffers::FlatBufferBuilder &entityDelta)
+{
+    PipelineState state(this, ModifiedPipeline, key, d->modifiedPipeline);
+    d->activePipelines << state;
+    state.step();
+}
+
+void Pipeline::deletedEntity(const QByteArray &key)
+{
+    PipelineState state(this, DeletedPipeline, key, d->deletedPipeline);
+    d->activePipelines << state;
+    state.step();
+}
+
+void Pipeline::pipelineStepped(const PipelineState &state)
+{
+    scheduleStep();
+}
+
+void Pipeline::scheduleStep()
+{
+    if (!d->stepScheduled) {
+        d->stepScheduled = true;
+        QMetaObject::invokeMethod(this, "stepPipelines", Qt::QueuedConnection);
+    }
+}
+
+void Pipeline::stepPipelines()
+{
+    for (PipelineState &state: d->activePipelines) {
+        if (state.isIdle()) {
+            state.step();
+        }
+    }
+
+    d->stepScheduled = false;
+}
+
+void Pipeline::pipelineCompleted(const PipelineState &state)
+{
+    //TODO finalize the datastore, inform clients of the new rev
+    const int index = d->activePipelines.indexOf(state);
+    if (index > -1) {
+        d->activePipelines.remove(index);
+    }
+
+    if (state.type() != NullPipeline) {
+        emit revisionUpdated();
+    }
+    scheduleStep();
+}
+
+
+class PipelineState::Private : public QSharedData
+{
+public:
+    Private(Pipeline *p, Pipeline::Type t, const QByteArray &k, QVector<PipelineFilter *> filters)
+        : pipeline(p),
+          type(t),
+          key(k),
+          filterIt(filters),
+          idle(true)
+    {}
+
+    Private()
+        : pipeline(0),
+          filterIt(QVector<PipelineFilter *>()),
+          idle(true)
+    {}
+
+    Pipeline *pipeline;
+    Pipeline::Type type;
+    QByteArray key;
+    QVectorIterator<PipelineFilter *> filterIt;
+    bool idle;
+};
+
+PipelineState::PipelineState()
+    : d(new Private())
+{
+
+}
+
+PipelineState::PipelineState(Pipeline *pipeline, Pipeline::Type type, const QByteArray &key, const QVector<PipelineFilter *> &filters)
+    : d(new Private(pipeline, type, key, filters))
+{
+}
+
+PipelineState::PipelineState(const PipelineState &other)
+    : d(other.d)
+{
+}
+
+PipelineState::~PipelineState()
+{
+}
+
+PipelineState &PipelineState::operator=(const PipelineState &rhs)
+{
+    d = rhs.d;
+    return *this;
+}
+
+bool PipelineState::operator==(const PipelineState &rhs)
+{
+    return d == rhs.d;
+}
+
+bool PipelineState::isIdle() const
+{
+    return d->idle;
+}
+
+QByteArray PipelineState::key() const
+{
+    return d->key;
+}
+
+Pipeline::Type PipelineState::type() const
+{
+    return d->type;
+}
+
+void PipelineState::step()
+{
+    if (!d->pipeline) {
+        return;
+    }
+
+    d->idle = false;
+    if (d->filterIt.hasNext()) {
+        d->filterIt.next()->process(*this);
+    } else {
+        d->pipeline->pipelineCompleted(*this);
+    }
+}
+
+void PipelineState::processingCompleted(PipelineFilter *filter)
+{
+    if (d->pipeline && filter == d->filterIt.peekPrevious()) {
+        d->idle = true;
+        d->pipeline->pipelineStepped(*this);
+    }
+}
+
+PipelineFilter::PipelineFilter()
+    : d(0)
 {
-    d->storage.write(key, keySize, buffer, bufferSize);
 }
 
-void Pipeline::newEntity(uint messageId, const char *key, size_t keySize, const char *buffer, size_t bufferSize)
+PipelineFilter::~PipelineFilter()
 {
-    d->storage.write(key, keySize, buffer, bufferSize);
 }
 
-void Pipeline::modifiedEntity(uint messageId, const char *key, size_t keySize, const char *buffer, size_t bufferSize)
+void PipelineFilter::process(PipelineState state)
 {
-    d->storage.write(key, keySize, buffer, bufferSize);
+    processingCompleted(state);
 }
 
-void Pipeline::deletedEntity(uint messageId, const char *key, size_t keySize, const char *buffer, size_t bufferSize)
+void PipelineFilter::processingCompleted(PipelineState state)
 {
-    d->storage.write(key, keySize, buffer, bufferSize);
+    state.processingCompleted(this);
 }
 
 } // namespace Akonadi2