Refactor event items

* TimelineItem and a newly introduced PendingEventItem are now
inheriting from the common EventItemBase class
* PendingEventItem has its own status and annotation, serving to track
transition of the item through pending states

6 files changed, 228 insertions, 71 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7be054e8..fa48db03 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -80,6 +80,7 @@ set(libqmatrixclient_SRCS
     lib/networksettings.cpp
     lib/converters.cpp
     lib/util.cpp
+    lib/eventitem.cpp
     lib/events/event.cpp
     lib/events/roomevent.cpp
     lib/events/stateevent.cpp
diff --git a/lib/eventitem.cpp b/lib/eventitem.cpp
index e69de29b..79ef769c 100644
--- a/lib/eventitem.cpp
+++ b/lib/eventitem.cpp
@@ -0,0 +1,19 @@
+/******************************************************************************
+ * Copyright (C) 2018 Kitsune Ral <kitsune-ral@users.sf.net>
+ *
+ * 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) any later version.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "eventitem.h"
diff --git a/lib/eventitem.h b/lib/eventitem.h
index 9e02fab0..6bec5a7f 100644
--- a/lib/eventitem.h
+++ b/lib/eventitem.h
@@ -1,4 +1,144 @@
-#ifndef EVENTITEM_H
-#define EVENTITEM_H
+/******************************************************************************
+ * Copyright (C) 2018 Kitsune Ral <kitsune-ral@users.sf.net>
+ *
+ * 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) any later version.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
 
-#endif // EVENTITEM_H
+#pragma once
+
+#include "events/stateevent.h"
+
+#include <utility>
+
+namespace QMatrixClient
+{
+    class StateEventBase;
+
+    class EventStatus
+    {
+            Q_GADGET
+        public:
+            /** Special marks an event can assume
+             *
+             * This is used to hint at a special status of some events in UI.
+             * Most status values are mutually exclusive.
+             */
+            enum Code {
+                Normal = 0x0,         //< No special designation
+                Submitted = 0x01,     //< The event has just been submitted for sending
+                Departed = 0x02,      //< The event has left the client
+                ReachedServer = 0x03, //< The server has received the event
+                SendingFailed = 0x04, //< The server could not receive the event
+                Redacted = 0x08,      //< The event has been redacted
+                Hidden = 0x10,        //< The event should be hidden
+            };
+            Q_DECLARE_FLAGS(Status, Code)
+            Q_FLAG(Status)
+    };
+
+    class EventItemBase
+    {
+        public:
+            explicit EventItemBase(RoomEventPtr&& e)
+                : evt(std::move(e))
+            {
+                Q_ASSERT(evt);
+            }
+
+            const RoomEvent* event() const { return rawPtr(evt); }
+            const RoomEvent* get() const { return event(); }
+            template <typename EventT>
+            const EventT* viewAs() const { return eventCast<const EventT>(evt); }
+            const RoomEventPtr& operator->() const { return evt; }
+            const RoomEvent& operator*() const { return *evt; }
+
+            // Used for event redaction
+            RoomEventPtr replaceEvent(RoomEventPtr&& other)
+            {
+                return std::exchange(evt, move(other));
+            }
+
+        private:
+            RoomEventPtr evt;
+    };
+
+    class TimelineItem : public EventItemBase
+    {
+        public:
+            // For compatibility with Qt containers, even though we use
+            // a std:: container now for the room timeline
+            using index_t = int;
+
+            TimelineItem(RoomEventPtr&& e, index_t number)
+                : EventItemBase(std::move(e)), idx(number)
+            { }
+
+            index_t index() const { return idx; }
+
+        private:
+            index_t idx;
+    };
+
+    template<>
+    inline const StateEventBase* EventItemBase::viewAs<StateEventBase>() const
+    {
+        return evt->isStateEvent() ? weakPtrCast<const StateEventBase>(evt)
+                                   : nullptr;
+    }
+
+    class PendingEventItem : public EventItemBase
+    {
+            Q_GADGET
+        public:
+            using EventItemBase::EventItemBase;
+
+            EventStatus::Code deliveryStatus() const { return _status; }
+            QDateTime lastUpdated() const { return _lastUpdated; }
+            QString annotation() const { return _annotation; }
+
+            void setDeparted() { setStatus(EventStatus::Departed); }
+            void setReachedServer(const QString& eventId)
+            {
+                setStatus(EventStatus::ReachedServer);
+                (*this)->addId(eventId);
+            }
+            void setSendingFailed(QString errorText)
+            {
+                setStatus(EventStatus::SendingFailed);
+                _annotation = std::move(errorText);
+            }
+            void resetStatus() { setStatus(EventStatus::Submitted); }
+
+        private:
+            EventStatus::Code _status = EventStatus::Submitted;
+            QDateTime _lastUpdated = QDateTime::currentDateTimeUtc();
+            QString _annotation;
+
+            void setStatus(EventStatus::Code status)
+            {
+                _status = status;
+                _lastUpdated = QDateTime::currentDateTimeUtc();
+                _annotation.clear();
+            }
+    };
+
+    inline QDebug& operator<<(QDebug& d, const TimelineItem& ti)
+    {
+        QDebugStateSaver dss(d);
+        d.nospace() << "(" << ti.index() << "|" << ti->id() << ")";
+        return d;
+    }
+}
+Q_DECLARE_METATYPE(QMatrixClient::EventStatus)
diff --git a/lib/room.cpp b/lib/room.cpp
index bfa6df68..e615060b 100644
--- a/lib/room.cpp
+++ b/lib/room.cpp
@@ -88,7 +88,7 @@ class Room::Private
 
         Connection* connection;
         Timeline timeline;
-        RoomEvents unsyncedEvents;
+        PendingEvents unsyncedEvents;
         QHash<QString, TimelineItem::index_t> eventsIndex;
         QString id;
         QStringList aliases;
@@ -207,6 +207,9 @@ class Room::Private
             return sendEvent(makeEvent<EventT>(std::forward<ArgTs>(eventArgs)...));
         }
 
+        QString doSendEvent(const RoomEvent* pEvent);
+        PendingEvents::iterator findAsPending(const RoomEvent* rawEvtPtr);
+
         template <typename EvT>
         auto requestSetState(const QString& stateKey, const EvT& event)
         {
@@ -250,11 +253,6 @@ class Room::Private
         }
 };
 
-RoomEventPtr TimelineItem::replaceEvent(RoomEventPtr&& other)
-{
-    return std::exchange(evt, move(other));
-}
-
 Room::Room(Connection* connection, QString id, JoinState initialJoinState)
     : QObject(connection), d(new Private(connection, id, initialJoinState))
 {
@@ -283,7 +281,7 @@ const Room::Timeline& Room::messageEvents() const
     return d->timeline;
 }
 
-const RoomEvents& Room::pendingEvents() const
+const Room::PendingEvents& Room::pendingEvents() const
 {
     return d->unsyncedEvents;
 }
@@ -1128,30 +1126,68 @@ void Room::updateData(SyncRoomData&& data)
 
 QString Room::Private::sendEvent(RoomEventPtr&& event)
 {
+    if (event->transactionId().isEmpty())
+        event->setTransactionId(connection->generateTxnId());
     auto* pEvent = rawPtr(event);
     emit q->pendingEventAboutToAdd();
     unsyncedEvents.emplace_back(move(event));
     emit q->pendingEventAdded();
+    return doSendEvent(pEvent);
+}
 
-    if (pEvent->transactionId().isEmpty())
-        pEvent->setTransactionId(connection->generateTxnId());
+QString Room::Private::doSendEvent(const RoomEvent* pEvent)
+{
+    auto txnId = pEvent->transactionId();
     // TODO: Enqueue the job rather than immediately trigger it
-    auto call = connection->sendMessage(id, *pEvent);
-    Room::connect(call, &BaseJob::success, q, [this,call,pEvent]
-    {
-        const auto comparator =
-            [pEvent] (const auto& eptr) { return rawPtr(eptr) == pEvent; };
+    auto call = connection->callApi<SendMessageJob>(BackgroundRequest,
+                    id, pEvent->matrixType(), txnId, pEvent->contentJson());
+    Room::connect(call, &BaseJob::started, q,
+        [this,pEvent,txnId] {
+            auto it = findAsPending(pEvent);
+            if (it == unsyncedEvents.end())
+            {
+                qWarning(EVENTS) << "Pending event for transaction" << txnId
+                                 << "not found - got synced so soon?";
+                return;
+            }
+            it->setDeparted();
+            emit q->pendingEventChanged(it - unsyncedEvents.begin());
+        });
+    Room::connect(call, &BaseJob::failure, q,
+        [this,pEvent,txnId,call] {
+            auto it = findAsPending(pEvent);
+            if (it == unsyncedEvents.end())
+            {
+                qCritical(EVENTS) << "Pending event for transaction" << txnId
+                                  << "got lost without successful sending";
+                return;
+            }
+            it->setSendingFailed(
+                        call->statusCaption() % ": " % call->errorString());
+            emit q->pendingEventChanged(it - unsyncedEvents.begin());
+
+        });
+    Room::connect(call, &BaseJob::success, q,
+        [this,call,pEvent] {
+            // Find an event by the pointer saved in the lambda (the pointer
+            // may be dangling by now but we can still search by it).
+            auto it = findAsPending(pEvent);
+            if (it == unsyncedEvents.end())
+                return; // The event is already synced, nothing to do
+
+            it->setReachedServer(call->eventId());
+            emit q->pendingEventChanged(it - unsyncedEvents.begin());
+        });
+    return txnId;
+}
 
-        // Find an event by the pointer saved in the lambda
-        auto it = std::find_if(unsyncedEvents.begin(), unsyncedEvents.end(),
-                               comparator);
-        if (it == unsyncedEvents.end())
-            return; // The event is already synced, nothing to do
+Room::PendingEvents::iterator Room::Private::findAsPending(
+        const RoomEvent* rawEvtPtr)
+{
+    const auto comp =
+        [rawEvtPtr] (const auto& pe) { return pe.event() == rawEvtPtr; };
 
-        pEvent->addId(call->eventId());
-        emit q->pendingEventChanged(it - unsyncedEvents.begin());
-    });
-    return pEvent->transactionId();
+    return std::find_if(unsyncedEvents.begin(), unsyncedEvents.end(), comp);
 }
 
 QString Room::postMessage(const QString& type, const QString& plainText)
@@ -1202,7 +1238,7 @@ void Room::setTopic(const QString& newTopic)
     d->requestSetState(RoomTopicEvent(newTopic));
 }
 
-bool isEchoEvent(const RoomEventPtr& le, const RoomEventPtr& re)
+bool isEchoEvent(const RoomEventPtr& le, const PendingEventItem& re)
 {
     if (le->type() != re->type())
         return false;
diff --git a/lib/room.h b/lib/room.h
index 599b7fbf..15e2146e 100644
--- a/lib/room.h
+++ b/lib/room.h
@@ -21,6 +21,7 @@
 #include "jobs/syncjob.h"
 #include "events/roommessageevent.h"
 #include "events/accountdataevents.h"
+#include "eventitem.h"
 #include "joinstate.h"
 
 #include <QtGui/QPixmap>
@@ -40,49 +41,6 @@ namespace QMatrixClient
     class SetRoomStateWithKeyJob;
     class RedactEventJob;
 
-    class TimelineItem
-    {
-        public:
-            // For compatibility with Qt containers, even though we use
-            // a std:: container now for the room timeline
-            using index_t = int;
-
-            TimelineItem(RoomEventPtr&& e, index_t number)
-                : evt(std::move(e)), idx(number)
-            {
-                Q_ASSERT(evt);
-            }
-
-            const RoomEvent* event() const { return rawPtr(evt); }
-            const RoomEvent* get() const { return event(); }
-            template <typename EventT>
-            const EventT* viewAs() const { return eventCast<const EventT>(evt); }
-            const RoomEventPtr& operator->() const { return evt; }
-            const RoomEvent& operator*() const { return *evt; }
-            index_t index() const { return idx; }
-
-            // Used for event redaction
-            RoomEventPtr replaceEvent(RoomEventPtr&& other);
-
-        private:
-            RoomEventPtr evt;
-            index_t idx;
-    };
-
-    template<>
-    inline const StateEventBase* TimelineItem::viewAs<StateEventBase>() const
-    {
-        return evt->isStateEvent() ? weakPtrCast<const StateEventBase>(evt)
-                                   : nullptr;
-    }
-
-    inline QDebug& operator<<(QDebug& d, const TimelineItem& ti)
-    {
-        QDebugStateSaver dss(d);
-        d.nospace() << "(" << ti.index() << "|" << ti->id() << ")";
-        return d;
-    }
-
     class FileTransferInfo
     {
             Q_GADGET
@@ -139,6 +97,7 @@ namespace QMatrixClient
 
         public:
             using Timeline = std::deque<TimelineItem>;
+            using PendingEvents = std::vector<PendingEventItem>;
             using rev_iter_t = Timeline::const_reverse_iterator;
             using timeline_iter_t = Timeline::const_iterator;
 
@@ -216,7 +175,7 @@ namespace QMatrixClient
             Q_INVOKABLE QString roomMembername(const QString& userId) const;
 
             const Timeline& messageEvents() const;
-            const RoomEvents& pendingEvents() const;
+            const PendingEvents& pendingEvents() const;
             /**
              * A convenience method returning the read marker to the before-oldest
              * message
diff --git a/libqmatrixclient.pri b/libqmatrixclient.pri
index 2f6a701a..f931be32 100644
--- a/libqmatrixclient.pri
+++ b/libqmatrixclient.pri
@@ -13,6 +13,7 @@ INCLUDEPATH += $$SRCPATH
 HEADERS += \
     $$SRCPATH/connectiondata.h \
     $$SRCPATH/connection.h \
+    $$SRCPATH/eventitem.h \
     $$SRCPATH/room.h \
     $$SRCPATH/user.h \
     $$SRCPATH/avatar.h \
@@ -49,6 +50,7 @@ HEADERS += \
 SOURCES += \
     $$SRCPATH/connectiondata.cpp \
     $$SRCPATH/connection.cpp \
+    $$SRCPATH/eventitem.cpp \
     $$SRCPATH/room.cpp \
     $$SRCPATH/user.cpp \
     $$SRCPATH/avatar.cpp \