Add ability to redact messages

9 files changed, 216 insertions, 79 deletions

diff --git a/include/ChatPage.h b/include/ChatPage.h
index c753aa97..cd516a71 100644
--- a/include/ChatPage.h
+++ b/include/ChatPage.h
@@ -72,6 +72,10 @@ public:
         {
                 client_->readEvent(room_id, event_id);
         }
+        void redactEvent(const QString &room_id, const QString &event_id)
+        {
+                client_->redactEvent(room_id, event_id);
+        }
 
         QSharedPointer<UserSettings> userSettings() { return userSettings_; }
 
diff --git a/include/MatrixClient.h b/include/MatrixClient.h
index 69fa72bc..3052a118 100644
--- a/include/MatrixClient.h
+++ b/include/MatrixClient.h
@@ -86,6 +86,7 @@ public:
         void sendTypingNotification(const QString &roomid, int timeoutInMillis = 20000);
         void removeTypingNotification(const QString &roomid);
         void readEvent(const QString &room_id, const QString &event_id);
+        void redactEvent(const QString &room_id, const QString &event_id);
         void inviteUser(const QString &room_id, const QString &user);
         void createRoom(const mtx::requests::CreateRoom &request);
 
@@ -171,6 +172,9 @@ signals:
         void leftRoom(const QString &room_id);
         void roomCreationFailed(const QString &msg);
 
+        void redactionFailed(const QString &error);
+        void redactionCompleted(const QString &room_id, const QString &event_id);
+
 private:
         QNetworkReply *makeUploadRequest(QSharedPointer<QIODevice> iodev);
         QJsonObject getUploadReply(QNetworkReply *reply);
diff --git a/include/timeline/TimelineItem.h b/include/timeline/TimelineItem.h
index 7c04e167..ade2f834 100644
--- a/include/timeline/TimelineItem.h
+++ b/include/timeline/TimelineItem.h
@@ -93,6 +93,9 @@ public:
                         ChatPage::instance()->readEvent(room_id_, event_id_);
         }
 
+        //! Add a user avatar for this event.
+        void addAvatar();
+
 protected:
         void paintEvent(QPaintEvent *event) override;
         void contextMenuEvent(QContextMenuEvent *event) override;
@@ -130,20 +133,18 @@ private:
         QMenu *contextMenu_;
         QAction *showReadReceipts_;
         QAction *markAsRead_;
+        QAction *redactMsg_;
 
-        QHBoxLayout *topLayout_;
-        //! The message and the timestamp/checkmark.
-        QHBoxLayout *messageLayout_;
-        //! Avatar or Timestamp
-        QVBoxLayout *sideLayout_;
-        //! Header & Message body
-        QVBoxLayout *mainLayout_;
-
-        QVBoxLayout *headerLayout_; // Username (&) Timestamp
+        QHBoxLayout *topLayout_     = nullptr;
+        QHBoxLayout *messageLayout_ = nullptr;
+        QVBoxLayout *mainLayout_    = nullptr;
+        QVBoxLayout *headerLayout_  = nullptr;
+        QHBoxLayout *widgetLayout_  = nullptr;
 
         Avatar *userAvatar_;
 
         QFont font_;
+        QFont usernameFont_;
 
         QLabel *timestamp_;
         QLabel *checkmark_;
@@ -169,26 +170,23 @@ TimelineItem::setupLocalWidgetLayout(Widget *widget,
 
         generateTimestamp(timestamp);
 
-        auto widgetLayout = new QHBoxLayout();
-        widgetLayout->setContentsMargins(0, 5, 0, 0);
-        widgetLayout->addWidget(widget);
-        widgetLayout->addStretch(1);
-
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
+        widgetLayout_ = new QHBoxLayout;
+        widgetLayout_->setContentsMargins(0, 5, 0, 0);
+        widgetLayout_->addWidget(widget);
+        widgetLayout_->addStretch(1);
 
         if (withSender) {
                 generateBody(displayName, "");
                 setupAvatarLayout(displayName);
 
-                headerLayout_->addLayout(widgetLayout);
+                headerLayout_->addLayout(widgetLayout_);
                 messageLayout_->addLayout(headerLayout_, 1);
 
                 AvatarProvider::resolve(userid, [this](const QImage &img) { setUserAvatar(img); });
         } else {
                 setupSimpleLayout();
 
-                messageLayout_->addLayout(widgetLayout, 1);
+                messageLayout_->addLayout(widgetLayout_, 1);
         }
 
         messageLayout_->addWidget(checkmark_);
@@ -220,26 +218,23 @@ TimelineItem::setupWidgetLayout(Widget *widget,
 
         generateTimestamp(timestamp);
 
-        auto widgetLayout = new QHBoxLayout();
-        widgetLayout->setContentsMargins(0, 5, 0, 0);
-        widgetLayout->addWidget(widget);
-        widgetLayout->addStretch(1);
-
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
+        widgetLayout_ = new QHBoxLayout();
+        widgetLayout_->setContentsMargins(0, 5, 0, 0);
+        widgetLayout_->addWidget(widget);
+        widgetLayout_->addStretch(1);
 
         if (withSender) {
                 generateBody(displayName, "");
                 setupAvatarLayout(displayName);
 
-                headerLayout_->addLayout(widgetLayout);
+                headerLayout_->addLayout(widgetLayout_);
                 messageLayout_->addLayout(headerLayout_, 1);
 
                 AvatarProvider::resolve(sender, [this](const QImage &img) { setUserAvatar(img); });
         } else {
                 setupSimpleLayout();
 
-                messageLayout_->addLayout(widgetLayout, 1);
+                messageLayout_->addLayout(widgetLayout_, 1);
         }
 
         messageLayout_->addWidget(checkmark_);
diff --git a/include/timeline/TimelineView.h b/include/timeline/TimelineView.h
index 2876cc60..78e092b3 100644
--- a/include/timeline/TimelineView.h
+++ b/include/timeline/TimelineView.h
@@ -101,6 +101,9 @@ public:
         void scrollDown();
         QLabel *createDateSeparator(QDateTime datetime);
 
+        //! Remove an item from the timeline with the given Event ID.
+        void removeEvent(const QString &event_id);
+
 public slots:
         void sliderRangeChanged(int min, int max);
         void sliderMoved(int position);
@@ -128,6 +131,8 @@ protected:
 private:
         using TimelineEvent = mtx::events::collections::TimelineEvents;
 
+        QWidget *relativeWidget(TimelineItem *item, int dt) const;
+
         //! HACK: Fixing layout flickering when adding to the bottom
         //! of the timeline.
         void pushTimelineItem(TimelineItem *item)
@@ -232,7 +237,7 @@ private:
         inline bool isNotifiable(const TimelineEvent &event) const;
 
         // The events currently rendered. Used for duplicate detection.
-        QMap<QString, bool> eventIds_;
+        QMap<QString, TimelineItem *> eventIds_;
         QQueue<PendingMessage> pending_msgs_;
         QList<PendingMessage> pending_sent_msgs_;
         QSharedPointer<MatrixClient> client_;
@@ -295,13 +300,9 @@ TimelineView::processMessageEvent(const Event &event, TimelineDirection directio
         const auto event_id = QString::fromStdString(event.event_id);
         const auto sender   = QString::fromStdString(event.sender);
 
-        if (isDuplicate(event_id))
-                return nullptr;
-
-        eventIds_[event_id] = true;
-
         const QString txnid = QString::fromStdString(event.unsigned_data.transaction_id);
-        if (!txnid.isEmpty() && isPendingMessage(txnid, sender, local_user_)) {
+        if ((!txnid.isEmpty() && isPendingMessage(txnid, sender, local_user_)) ||
+            isDuplicate(event_id)) {
                 removePendingMessage(txnid);
                 return nullptr;
         }
@@ -310,7 +311,11 @@ TimelineView::processMessageEvent(const Event &event, TimelineDirection directio
 
         updateLastSender(sender, direction);
 
-        return createTimelineItem<Event>(event, with_sender);
+        auto item = createTimelineItem<Event>(event, with_sender);
+
+        eventIds_[event_id] = item;
+
+        return item;
 }
 
 template<class Event, class Widget>
@@ -320,13 +325,9 @@ TimelineView::processMessageEvent(const Event &event, TimelineDirection directio
         const auto event_id = QString::fromStdString(event.event_id);
         const auto sender   = QString::fromStdString(event.sender);
 
-        if (isDuplicate(event_id))
-                return nullptr;
-
-        eventIds_[event_id] = true;
-
         const QString txnid = QString::fromStdString(event.unsigned_data.transaction_id);
-        if (!txnid.isEmpty() && isPendingMessage(txnid, sender, local_user_)) {
+        if ((!txnid.isEmpty() && isPendingMessage(txnid, sender, local_user_)) ||
+            isDuplicate(event_id)) {
                 removePendingMessage(txnid);
                 return nullptr;
         }
@@ -335,5 +336,9 @@ TimelineView::processMessageEvent(const Event &event, TimelineDirection directio
 
         updateLastSender(sender, direction);
 
-        return createTimelineItem<Event, Widget>(event, with_sender);
+        auto item = createTimelineItem<Event, Widget>(event, with_sender);
+
+        eventIds_[event_id] = item;
+
+        return item;
 }
diff --git a/src/ChatPage.cc b/src/ChatPage.cc
index fee4f982..158427fd 100644
--- a/src/ChatPage.cc
+++ b/src/ChatPage.cc
@@ -342,6 +342,9 @@ ChatPage::ChatPage(QSharedPointer<MatrixClient> client,
                 emit showNotification(QString("Room %1 created").arg(room_id));
         });
         connect(client_.data(), &MatrixClient::leftRoom, this, &ChatPage::removeRoom);
+        connect(client_.data(), &MatrixClient::redactionFailed, this, [this](const QString &error) {
+                emit showNotification(QString("Message redaction failed: %1").arg(error));
+        });
 
         showContentTimer_ = new QTimer(this);
         showContentTimer_->setSingleShot(true);
diff --git a/src/MatrixClient.cc b/src/MatrixClient.cc
index 4a4fc67c..5f9e1b86 100644
--- a/src/MatrixClient.cc
+++ b/src/MatrixClient.cc
@@ -1281,3 +1281,47 @@ MatrixClient::getUploadReply(QNetworkReply *reply)
 
         return object;
 }
+
+void
+MatrixClient::redactEvent(const QString &room_id, const QString &event_id)
+{
+        QUrlQuery query;
+        query.addQueryItem("access_token", token_);
+
+        QUrl endpoint(server_);
+        endpoint.setPath(clientApiUrl_ + QString("/rooms/%1/redact/%2/%3")
+                                           .arg(room_id)
+                                           .arg(event_id)
+                                           .arg(incrementTransactionId()));
+        endpoint.setQuery(query);
+
+        QNetworkRequest request(QString(endpoint.toEncoded()));
+        request.setHeader(QNetworkRequest::KnownHeaders::ContentTypeHeader, "application/json");
+
+        // TODO: no reason specified
+        QJsonObject body{};
+        auto reply = put(request, QJsonDocument(body).toJson(QJsonDocument::Compact));
+
+        connect(reply, &QNetworkReply::finished, this, [reply, this, room_id, event_id]() {
+                reply->deleteLater();
+
+                int status = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
+                auto data  = reply->readAll();
+
+                if (status == 0 || status >= 400) {
+                        try {
+                                mtx::errors::Error res = nlohmann::json::parse(data);
+                                emit redactionFailed(QString::fromStdString(res.error));
+                                return;
+                        } catch (const std::exception &) {
+                        }
+                }
+
+                try {
+                        mtx::responses::EventId res = nlohmann::json::parse(data);
+                        emit redactionCompleted(room_id, event_id);
+                } catch (const std::exception &e) {
+                        emit redactionFailed(QString::fromStdString(e.what()));
+                }
+        });
+}
diff --git a/src/timeline/TimelineItem.cc b/src/timeline/TimelineItem.cc
index 2f04a1bd..371ced10 100644
--- a/src/timeline/TimelineItem.cc
+++ b/src/timeline/TimelineItem.cc
@@ -40,29 +40,39 @@ TimelineItem::init()
         body_       = nullptr;
 
         font_.setPixelSize(conf::fontSize);
+        usernameFont_ = font_;
+        usernameFont_.setWeight(60);
 
         QFontMetrics fm(font_);
 
         contextMenu_      = new QMenu(this);
         showReadReceipts_ = new QAction("Read receipts", this);
         markAsRead_       = new QAction("Mark as read", this);
+        redactMsg_        = new QAction("Redact message", this);
         contextMenu_->addAction(showReadReceipts_);
         contextMenu_->addAction(markAsRead_);
+        contextMenu_->addAction(redactMsg_);
 
         connect(showReadReceipts_, &QAction::triggered, this, [this]() {
                 if (!event_id_.isEmpty())
                         ChatPage::instance()->showReadReceipts(event_id_);
         });
 
+        connect(redactMsg_, &QAction::triggered, this, [this]() {
+                if (!event_id_.isEmpty())
+                        ChatPage::instance()->redactEvent(room_id_, event_id_);
+        });
+
         connect(markAsRead_, &QAction::triggered, this, [this]() { sendReadReceipt(); });
 
         topLayout_     = new QHBoxLayout(this);
         mainLayout_    = new QVBoxLayout;
         messageLayout_ = new QHBoxLayout;
+        messageLayout_->setContentsMargins(0, 0, 20, 4);
+        messageLayout_->setSpacing(20);
 
         topLayout_->setContentsMargins(conf::timeline::msgMargin, conf::timeline::msgMargin, 0, 0);
         topLayout_->setSpacing(0);
-
         topLayout_->addLayout(mainLayout_, 1);
 
         mainLayout_->setContentsMargins(conf::timeline::headerLeftMargin, 0, 0, 0);
@@ -73,7 +83,7 @@ TimelineItem::init()
 
         // Setting fixed width for checkmark because systems may have a differing width for a
         // space and the Unicode checkmark.
-        checkmark_ = new QLabel(" ", this);
+        checkmark_ = new QLabel(this);
         checkmark_->setFont(checkmarkFont);
         checkmark_->setFixedWidth(QFontMetrics{checkmarkFont}.width(CHECKMARK));
 }
@@ -106,9 +116,6 @@ TimelineItem::TimelineItem(mtx::events::MessageType ty,
         body.replace("\n", "<br/>");
         generateTimestamp(timestamp);
 
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
-
         if (withSender) {
                 generateBody(displayName, body);
                 setupAvatarLayout(displayName);
@@ -240,9 +247,6 @@ TimelineItem::TimelineItem(const mtx::events::RoomEvent<mtx::events::msg::Notice
         body.replace("\n", "<br/>");
         body = "<i>" + body + "</i>";
 
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
-
         if (with_sender) {
                 auto displayName = TimelineViewManager::displayName(sender);
 
@@ -289,9 +293,6 @@ TimelineItem::TimelineItem(const mtx::events::RoomEvent<mtx::events::msg::Emote>
         emoteMsg.replace(conf::strings::url_regex, conf::strings::url_html);
         emoteMsg.replace("\n", "<br/>");
 
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
-
         if (with_sender) {
                 generateBody(displayName, emoteMsg);
                 setupAvatarLayout(displayName);
@@ -341,9 +342,6 @@ TimelineItem::TimelineItem(const mtx::events::RoomEvent<mtx::events::msg::Text>
         body.replace(conf::strings::url_regex, conf::strings::url_html);
         body.replace("\n", "<br/>");
 
-        messageLayout_->setContentsMargins(0, 0, 20, 4);
-        messageLayout_->setSpacing(20);
-
         if (with_sender) {
                 generateBody(displayName, body);
                 setupAvatarLayout(displayName);
@@ -400,25 +398,13 @@ TimelineItem::generateBody(const QString &userid, const QString &body)
                         sender = userid.split(":")[0].split("@")[1];
         }
 
-        QFont usernameFont = font_;
-        usernameFont.setWeight(60);
-
-        QFontMetrics fm(usernameFont);
+        QFontMetrics fm(usernameFont_);
 
         userName_ = new QLabel(this);
-        userName_->setFont(usernameFont);
+        userName_->setFont(usernameFont_);
         userName_->setText(fm.elidedText(sender, Qt::ElideRight, 500));
 
-        if (body.isEmpty())
-                return;
-
-        body_ = new QLabel(this);
-        body_->setFont(font_);
-        body_->setWordWrap(true);
-        body_->setText(QString("<span>%1</span>").arg(replaceEmoji(body)));
-        body_->setTextInteractionFlags(Qt::TextSelectableByMouse | Qt::TextBrowserInteraction);
-        body_->setOpenExternalLinks(true);
-        body_->setMargin(0);
+        generateBody(body);
 }
 
 void
@@ -474,12 +460,8 @@ TimelineItem::setupAvatarLayout(const QString &userName)
         if (userName[0] == '@' && userName.size() > 1)
                 userAvatar_->setLetter(QChar(userName[1]).toUpper());
 
-        sideLayout_ = new QVBoxLayout;
-        sideLayout_->setMargin(0);
-        sideLayout_->setSpacing(0);
-        sideLayout_->addWidget(userAvatar_);
-        sideLayout_->addStretch(1);
-        topLayout_->insertLayout(0, sideLayout_);
+        topLayout_->insertWidget(0, userAvatar_);
+        topLayout_->setAlignment(userAvatar_, Qt::AlignTop);
 
         headerLayout_ = new QVBoxLayout;
         headerLayout_->setMargin(0);
@@ -492,8 +474,8 @@ TimelineItem::setupAvatarLayout(const QString &userName)
 void
 TimelineItem::setupSimpleLayout()
 {
-        topLayout_->setContentsMargins(conf::timeline::avatarSize + conf::timeline::msgMargin + 1,
-                                       conf::timeline::msgMargin / 3,
+        topLayout_->setContentsMargins(conf::timeline::msgMargin + conf::timeline::avatarSize + 2,
+                                       conf::timeline::msgMargin,
                                        0,
                                        0);
 }
@@ -533,3 +515,48 @@ TimelineItem::addSaveImageAction(ImageItem *image)
                 connect(saveImage, &QAction::triggered, image, &ImageItem::saveAs);
         }
 }
+
+void
+TimelineItem::addAvatar()
+{
+        if (userAvatar_)
+                return;
+
+        // TODO: should be replaced with the proper event struct.
+        auto userid      = descriptionMsg_.userid;
+        auto displayName = TimelineViewManager::displayName(userid);
+
+        QFontMetrics fm(usernameFont_);
+        userName_ = new QLabel(this);
+        userName_->setFont(usernameFont_);
+        userName_->setText(fm.elidedText(displayName, Qt::ElideRight, 500));
+
+        QWidget *widget = nullptr;
+
+        // Extract the widget before we delete its layout.
+        if (widgetLayout_)
+                widget = widgetLayout_->itemAt(0)->widget();
+
+        // Remove all items from the layout.
+        QLayoutItem *item;
+        while ((item = messageLayout_->takeAt(0)) != 0)
+                delete item;
+
+        setupAvatarLayout(displayName);
+
+        // Restore widget's layout.
+        if (widget) {
+                widgetLayout_ = new QHBoxLayout();
+                widgetLayout_->setContentsMargins(0, 5, 0, 0);
+                widgetLayout_->addWidget(widget);
+                widgetLayout_->addStretch(1);
+
+                headerLayout_->addLayout(widgetLayout_);
+        }
+
+        messageLayout_->addLayout(headerLayout_, 1);
+        messageLayout_->addWidget(checkmark_);
+        messageLayout_->addWidget(timestamp_);
+
+        AvatarProvider::resolve(userid, [this](const QImage &img) { setUserAvatar(img); });
+}
diff --git a/src/timeline/TimelineView.cc b/src/timeline/TimelineView.cc
index 7e281e03..ded5ad2c 100644
--- a/src/timeline/TimelineView.cc
+++ b/src/timeline/TimelineView.cc
@@ -491,6 +491,7 @@ TimelineView::updatePendingMessage(int txn_id, QString event_id)
                 if (msg.widget) {
                         msg.widget->setEventId(event_id);
                         msg.widget->markReceived();
+                        eventIds_[event_id] = msg.widget;
                 }
 
                 pending_sent_msgs_.append(msg);
@@ -591,6 +592,9 @@ TimelineView::isPendingMessage(const QString &txnid,
 void
 TimelineView::removePendingMessage(const QString &txnid)
 {
+        if (txnid.isEmpty())
+                return;
+
         for (auto it = pending_sent_msgs_.begin(); it != pending_sent_msgs_.end(); ++it) {
                 if (QString::number(it->txn_id) == txnid) {
                         int index = std::distance(pending_sent_msgs_.begin(), it);
@@ -739,3 +743,44 @@ TimelineView::toggleScrollDownButton()
                 scrollDownBtn_->hide();
         }
 }
+
+void
+TimelineView::removeEvent(const QString &event_id)
+{
+        if (!eventIds_.contains(event_id)) {
+                qWarning() << "unknown event_id couldn't be removed:" << event_id;
+                return;
+        }
+
+        auto removedItem = eventIds_[event_id];
+
+        // Find the next and the previous widgets in the timeline
+        auto prevItem = qobject_cast<TimelineItem *>(relativeWidget(removedItem, -1));
+        auto nextItem = qobject_cast<TimelineItem *>(relativeWidget(removedItem, 1));
+
+        // If it's a TimelineItem add an avatar.
+        if (prevItem)
+                prevItem->addAvatar();
+
+        if (nextItem)
+                nextItem->addAvatar();
+
+        // Finally remove the event.
+        removedItem->deleteLater();
+        eventIds_.remove(event_id);
+}
+
+QWidget *
+TimelineView::relativeWidget(TimelineItem *item, int dt) const
+{
+        int pos = scroll_layout_->indexOf(item);
+
+        if (pos == -1)
+                return nullptr;
+
+        pos = pos + dt;
+
+        bool isOutOfBounds = (pos <= 0 || pos > scroll_layout_->count() - 1);
+
+        return isOutOfBounds ? nullptr : scroll_layout_->itemAt(pos)->widget();
+}
diff --git a/src/timeline/TimelineViewManager.cc b/src/timeline/TimelineViewManager.cc
index ccbf509b..55f25dfc 100644
--- a/src/timeline/TimelineViewManager.cc
+++ b/src/timeline/TimelineViewManager.cc
@@ -44,6 +44,16 @@ TimelineViewManager::TimelineViewManager(QSharedPointer<MatrixClient> client, QW
                 &MatrixClient::messageSendFailed,
                 this,
                 &TimelineViewManager::messageSendFailed);
+
+        connect(client_.data(),
+                &MatrixClient::redactionCompleted,
+                this,
+                [this](const QString &room_id, const QString &event_id) {
+                        auto view = views_[room_id];
+
+                        if (view)
+                                view->removeEvent(event_id);
+                });
 }
 
 void