Add rich replying and editing support

Cc #596
Closes #447

client/chatroomwidget.cpp

@@ -52,6 +52,7 @@
 #include "quaternionroom.h"
 #include "chatedit.h"
 #include "htmlfilter.h"
+#include "models/messageeventmodel.h"
 
 static auto DefaultPlaceholderText()
 {
@@ -84,6 +85,13 @@ ChatRoomWidget::ChatRoomWidget(MainWindow* parent)
     m_hudCaption->setFont(f);
     m_hudCaption->setTextFormat(Qt::RichText);
 
+    m_modeIndicator = new QToolButton();
+    m_modeIndicator->setAutoRaise(true);
+    m_modeIndicator->hide();
+    connect(m_modeIndicator, &QToolButton::clicked, this, [this] {
+        setDefaultMode();
+    });
+
     auto attachButton = new QToolButton();
     attachButton->setAutoRaise(true);
     m_attachAction = new QAction(QIcon::fromTheme("mail-attachment"),
@@ -207,6 +215,7 @@ ChatRoomWidget::ChatRoomWidget(MainWindow* parent)
     layout->addWidget(m_hudCaption);
     {
         auto inputLayout = new QHBoxLayout;
+        inputLayout->addWidget(m_modeIndicator);
         inputLayout->addWidget(attachButton);
         inputLayout->addWidget(m_chatEdit);
         layout->addLayout(inputLayout);
@@ -262,6 +271,7 @@ void ChatRoomWidget::setRoom(QuaternionRoom* newRoom)
     }
     typingChanged();
     encryptionChanged();
+    setDefaultMode();
 }
 
 void ChatRoomWidget::typingChanged()
@@ -416,38 +426,77 @@ void ChatRoomWidget::sendFile()
     m_chatEdit->setPlaceholderText(DefaultPlaceholderText());
 }
 
-#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
-void sendMarkdown(QuaternionRoom* room, const QTextDocumentFragment& text)
-{
-    room->postHtmlText(text.toPlainText(),
-                       HtmlFilter::toMatrixHtml(text.toHtml(), room,
-                                                HtmlFilter::ConvertMarkdown));
-}
-#endif
-
 void ChatRoomWidget::sendMessage()
 {
     if (m_chatEdit->toPlainText().startsWith("//"))
         QTextCursor(m_chatEdit->document()).deleteChar();
 
+    QTextCursor c(m_chatEdit->document());
+    c.select(QTextCursor::Document);
+    sendMessageFromFragment(c.selection());
+}
+
+void ChatRoomWidget::sendMessageFromFragment(const QTextDocumentFragment& text, bool markdown)
+{
+    const auto& plainText = text.toPlainText();
+    const auto& htmlText =
+        HtmlFilter::toMatrixHtml(text.toHtml(), currentRoom(),
 #if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
-    if (m_uiSettings.get("auto_markdown", false)) {
-        sendMarkdown(currentRoom(),
-                     QTextDocumentFragment(m_chatEdit->document()));
-        return;
-    }
+                    (m_uiSettings.get("auto_markdown", false) || markdown) ?
+                        HtmlFilter::ConvertMarkdown :
 #endif
-    const auto& plainText = m_chatEdit->toPlainText();
-    const auto& htmlText =
-        HtmlFilter::toMatrixHtml(m_chatEdit->toHtml(), currentRoom());
+                        HtmlFilter::Default
+        );
     Q_ASSERT(!plainText.isEmpty() && !htmlText.isEmpty());
     // Send plain text if htmlText has no markup or just <br/> elements
     // (those are easily represented as line breaks in plain text)
     static const QRegularExpression MarkupRE { "<(?![Bb][Rr])" };
-    if (htmlText.contains(MarkupRE))
-        currentRoom()->postHtmlText(plainText, htmlText);
-    else
-        currentRoom()->postPlainText(plainText);
+
+    using namespace Quotient;
+    switch (mode) {
+        case Editing:
+            {
+                // Any quotation is ignored intentionally, see
+                // https://spec.matrix.org/latest/client-server-api/#edits-of-replies
+                auto eventRelation = EventRelation::replace(
+                    reference.data(MessageEventModel::EventIdRole).toString()
+                );
+                EventContent::TextContent* textContent;
+                if (htmlText.contains(MarkupRE)) {
+                    textContent = new EventContent::TextContent(htmlText,
+                            QStringLiteral("text/html"), eventRelation);
+                } else {
+                    textContent = new EventContent::TextContent("",
+                            QStringLiteral("text/plain"), eventRelation);
+                }
+                auto roomMessageEvent = new RoomMessageEvent(plainText,
+                        MessageEventType::Text, textContent);
+                currentRoom()->postEvent(roomMessageEvent);
+            }
+            break;
+        case Replying:
+            {
+                QString htmlQuotation, plainTextQuotation;
+                if (reference.isValid()) {
+                    htmlQuotation = reference.data(MessageEventModel::HtmlQuotationRole).toString();
+                    plainTextQuotation = reference.data(MessageEventModel::QuotationRole).toString();
+                }
+                auto textContent = new EventContent::TextContent(htmlQuotation + htmlText,
+                        QStringLiteral("text/html"),
+                        EventRelation::replyTo(
+                            reference.data(MessageEventModel::EventIdRole).toString()
+                        ));
+                auto roomMessageEvent = new RoomMessageEvent(plainTextQuotation + plainText,
+                        MessageEventType::Text, textContent);
+                currentRoom()->postEvent(roomMessageEvent);
+            }
+            break;
+        default:
+            if (htmlText.contains(MarkupRE))
+                currentRoom()->postHtmlText(plainText, htmlText);
+            else
+                currentRoom()->postPlainText(plainText);
+    }
 }
 
 static auto NothingToSendMsg()
@@ -682,7 +731,7 @@ QString ChatRoomWidget::sendCommand(QStringView command,
         QTextCursor c(m_chatEdit->document());
         c.movePosition(QTextCursor::Right, QTextCursor::MoveAnchor, 4);
         c.movePosition(QTextCursor::End, QTextCursor::KeepAnchor);
-        sendMarkdown(currentRoom(), c.selection());
+        sendMessageFromFragment(c.selection(), true);
         return {};
 #else
         return tr("Your build of Quaternion doesn't support Markdown");
@@ -731,6 +780,27 @@ void ChatRoomWidget::sendInput()
     }
 
     m_chatEdit->saveInput();
+    setDefaultMode();
+}
+
+void ChatRoomWidget::setDefaultMode()
+{
+    mode = Default;
+    emit m_timelineWidget->setCurrentIndex(-1);
+    reference = QModelIndex();
+    m_modeIndicator->hide();
+}
+
+void ChatRoomWidget::setReferringMode(const int newMode, const QModelIndex& referredIndex, const char *icon_name)
+{
+    Q_ASSERT( newMode == Replying || newMode == Editing );
+    mode = newMode;
+    reference = referredIndex;
+    emit m_timelineWidget->setCurrentIndex(referredIndex.row());
+
+    m_modeIndicator->setIcon(QIcon::fromTheme(icon_name));
+
+    m_modeIndicator->show();
 }
 
 ChatRoomWidget::completions_t
@@ -789,6 +859,25 @@ void ChatRoomWidget::quote(const QString& htmlText)
     m_chatEdit->insertPlainText(sendString);
 }
 
+void ChatRoomWidget::reply(const QString& eventId, const QModelIndex& modelIndex)
+{
+    setReferringMode(Replying, modelIndex, "mail-reply-sender");
+    setHudHtml(tr("Reply message"));
+}
+
+void ChatRoomWidget::edit(const QString& eventId, const QModelIndex& modelIndex)
+{
+    // Might it be a good idea to detect markdown text in the plain text body
+    // here and if found then present that for the user instead of the rich
+    // body?
+    auto htmlText = modelIndex.data(MessageEventModel::NudeRichBodyRole).toString();
+
+    m_chatEdit->clear();
+    m_chatEdit->insertHtml(htmlText);
+    setReferringMode(Editing, modelIndex, "edit-entry");
+    setHudHtml(tr("Edit message"));
+}
+
 void ChatRoomWidget::resizeEvent(QResizeEvent*)
 {
     m_chatEdit->setMaximumHeight(maximumChatEditHeight());

client/chatroomwidget.h

@@ -24,6 +24,8 @@
 #include <settings.h>
 
 #include <QtWidgets/QWidget>
+#include <QtWidgets/QToolButton>
+#include <QtCore/QModelIndex>
 
 class TimelineWidget;
 class QuaternionRoom;
@@ -41,6 +43,12 @@ class User;
 
 class ChatRoomWidget : public QWidget
 {
+        enum Modes {
+            Default,
+            Replying,
+            Editing,
+        };
+
         Q_OBJECT
     public:
         using completions_t = ChatEdit::completions_t;
@@ -63,6 +71,8 @@ class ChatRoomWidget : public QWidget
 
         void typingChanged();
         void quote(const QString& htmlText);
+        void edit(const QString& eventId, const QModelIndex& modelIndex);
+        void reply(const QString& eventId, const QModelIndex& modelIndex);
         void fileDrop(const QString& url);
         void htmlDrop(const QString& html);
         void textDrop(const QString& text);
@@ -74,20 +84,28 @@ class ChatRoomWidget : public QWidget
     private:
         TimelineWidget* m_timelineWidget;
         QLabel* m_hudCaption; //< For typing and completion notifications
+        QToolButton* m_modeIndicator;
         QAction* m_attachAction;
         ChatEdit* m_chatEdit;
 
+        int mode;
+        QModelIndex reference;
+
         QString attachedFileName;
         QTemporaryFile* m_fileToAttach;
         Quotient::SettingsGroup m_uiSettings;
 
         MainWindow* mainWindow() const;
         QuaternionRoom* currentRoom() const;
 
+        void setDefaultMode();
+        void setReferringMode(const int newMode, const QModelIndex& referredIndex, const char *icon_name);
+
         void sendFile();
         void sendMessage();
         [[nodiscard]] QString sendCommand(QStringView command,
                                           const QString& argString);
+        void sendMessageFromFragment(const QTextDocumentFragment& text, bool markdown = false);
 
         void resizeEvent(QResizeEvent*) override;
         void keyPressEvent(QKeyEvent* event) override;

client/models/messageeventmodel.cpp

@@ -28,6 +28,7 @@
 #include <connection.h>
 #include <user.h>
 #include <settings.h>
+#include <uri.h>
 #include <events/encryptionevent.h>
 #include <events/roommemberevent.h>
 #include <events/simplestateevents.h>
@@ -59,6 +60,9 @@ QHash<int, QByteArray> MessageEventModel::roleNames() const
         roles.insert(EventResolvedTypeRole, "eventResolvedType");
         roles.insert(RefRole, "refId");
         roles.insert(ReactionsRole, "reactions");
+        roles.insert(NudeRichBodyRole, "nudeRichBody");
+        roles.insert(QuotationRole, "quotation");
+        roles.insert(HtmlQuotationRole, "htmlQuotation");
         return roles;
     }();
     return roles;
@@ -919,5 +923,70 @@ QVariant MessageEventModel::data(const QModelIndex& idx, int role) const
             evt, [](const RoomCreateEvent& e) { return e.predecessor().roomId; },
             [](const RoomTombstoneEvent& e) { return e.successorRoomId(); });
 
+    if (role == NudeRichBodyRole)
+    {
+        if (auto e = eventCast<const Quotient::RoomMessageEvent>(&evt)) {
+            if (!e->hasTextContent())
+                return QString();
+
+            static const QRegularExpression quoteBlock {
+                "<mx-reply>.*</mx-reply>",
+                QRegularExpression::DotMatchesEverythingOption
+            };
+            static const QRegularExpression quoteLines("> .*(?:\n|$)");
+            QString nudeBody;
+            if (e->mimeType().name() != "text/plain") {
+                // Naïvely assume that it's HTML
+                auto htmlBody =
+                    static_cast<const MessageEventContent::TextContent*>(e->content())->body;
+                auto [cleanHtml, errorPos, errorString] =
+                    HtmlFilter::fromMatrixHtml(htmlBody, m_currentRoom);
+                if (errorPos == -1) {
+                    nudeBody = cleanHtml.remove(quoteBlock);
+                }
+            }
+            if (nudeBody.isEmpty()) {
+                nudeBody = m_currentRoom->prettyPrint(e->plainBody().remove(quoteLines));
+            }
+            return nudeBody;
+        }
+    }
+
+    if (role == QuotationRole)
+    {
+        if (auto e = eventCast<const Quotient::RoomMessageEvent>(&evt)) {
+            if (!e->hasTextContent())
+                return QString();
+
+            static const QRegularExpression quoteLines("> .*(?:\n|$)");
+            static const QRegularExpression eachLine("(.+)(?:\n|$)");
+            const auto quotePrefix = QStringLiteral("> \\1\n");
+            const auto authorUser = isPending ? m_currentRoom->localUser() : m_currentRoom->user(evt.senderId());
+            const auto authorId = authorUser->id();
+
+            QString quotation = e->plainBody().remove(quoteLines);
+            return QStringLiteral("<%1> %2").arg(authorId, quotation).
+                    replace(eachLine, quotePrefix);
+        }
+    }
+
+    if (role == HtmlQuotationRole)
+    {
+        if (auto e = eventCast<const Quotient::RoomMessageEvent>(&evt)) {
+            QString quotation = data(idx, NudeRichBodyRole).toString();
+            if (quotation.isEmpty())
+                return QString();
+            const auto authorUser = isPending ? m_currentRoom->localUser() : m_currentRoom->user(evt.senderId());
+            const QString eventId = !evt.id().isEmpty() ? evt.id() : evt.transactionId();
+            const QString evtLink = "https://matrix.to/#/" + m_currentRoom->id() + "/" + eventId;
+            const QString authorName = authorUser->displayname(m_currentRoom);
+            const QString authorLink = Uri(authorUser->id()).toUrl(Uri::MatrixToUri).toString();
+
+            return QStringLiteral(
+                "<mx-reply><blockquote><a href=\"%1\">In reply to</a> <a href=\"%2\">%3</a><br />%4</blockquote></mx-reply>"
+            ).arg(evtLink, authorLink, authorName, quotation);
+        }
+    }
+
     return {};
 }

client/models/messageeventmodel.h

@@ -45,6 +45,9 @@ class MessageEventModel: public QAbstractListModel
             RefRole,
             ReactionsRole,
             EventResolvedTypeRole,
+            NudeRichBodyRole,
+            QuotationRole,
+            HtmlQuotationRole,
         };
 
         explicit MessageEventModel(QObject* parent = nullptr);

client/qml/Timeline.qml

@@ -242,6 +242,19 @@ Page {
         boundsMovement: Flickable.StopAtBounds
 //        pixelAligned: true // Causes false-negatives in atYEnd
         cacheBuffer: 200
+        highlight: Component {
+            Rectangle {
+                color: defaultPalette.highlight
+                radius: 5
+                Behavior on y {
+                    SpringAnimation {
+                        spring: 3
+                        damping: 0.2
+                    }
+                }
+            }
+        }
+        highlightFollowsCurrentItem: true
 
         clip: true
         ScrollBar.vertical: ScrollBar {
@@ -466,6 +479,8 @@ Page {
                                     - sectionBanner.childrenRect.height)
             onViewPositionRequested:
                 chatView.scrollViewTo(index, ListView.Contain, true)
+            onSetCurrentIndex:
+                chatView.currentIndex = index
         }
 
         Component.onCompleted: {