Foldable State Events

Implement folding sections for multiple consecutive state events. This also reworks some of the aggregated text output:

- Only new days cause a new section
- The aggregated text starts with either a single username or n users
- If the same user did the same action mutltiple times it will be in the aggregated text a user did x n times
- When there are multiple authors in a block with multiple state event types it will use or rather than and before the last event. e.g 3 user left the room or joined the room.

Folded

![image](/uploads/17141ed5e1f2e0e3539523a082275976/image.png)

Unfolded

![image](/uploads/1d5db5804da457b921544cc81099997d/image.png)

Implements network/neochat#90

src/models/collapsestateproxymodel.cpp

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: LGPL-2.0-or-later
 
 #include "collapsestateproxymodel.h"
+#include "messageeventmodel.h"
 
 #include <KLocalizedString>
 
@@ -12,18 +13,17 @@ bool CollapseStateProxyModel::filterAcceptsRow(int source_row, const QModelIndex
         != MessageEventModel::DelegateType::State // If this is not a state, show it
         || sourceModel()->data(sourceModel()->index(source_row + 1, 0), MessageEventModel::EventTypeRole)
         != MessageEventModel::DelegateType::State // If this is the first state in a block, show it. TODO hidden events?
-        || sourceModel()->data(sourceModel()->index(source_row, 0), MessageEventModel::ShowSectionRole).toBool() // If it's a new day, show it
-        || sourceModel()->data(sourceModel()->index(source_row, 0), MessageEventModel::EventResolvedTypeRole)
-        != sourceModel()->data(sourceModel()->index(source_row + 1, 0),
-                               MessageEventModel::EventResolvedTypeRole) // Also show it if it's of a different type than the one before TODO improve in
-        || sourceModel()->data(sourceModel()->index(source_row, 0), MessageEventModel::AuthorIdRole)
-        != sourceModel()->data(sourceModel()->index(source_row + 1, 0), MessageEventModel::AuthorIdRole); // Also show it if it's a different author
+        || sourceModel()->data(sourceModel()->index(source_row, 0), MessageEventModel::ShowSectionRole).toBool(); // If it's a new day, show it
 }
 
 QVariant CollapseStateProxyModel::data(const QModelIndex &index, int role) const
 {
     if (role == AggregateDisplayRole) {
         return aggregateEventToString(mapToSource(index).row());
+    } else if (role == StateEventsRole) {
+        return stateEventsList(mapToSource(index).row());
+    } else if (role == AuthorListRole) {
+        return authorList(mapToSource(index).row());
     }
     return sourceModel()->data(mapToSource(index), role);
 }
@@ -32,27 +32,29 @@ QHash<int, QByteArray> CollapseStateProxyModel::roleNames() const
 {
     auto roles = sourceModel()->roleNames();
     roles[AggregateDisplayRole] = "aggregateDisplay";
+    roles[StateEventsRole] = "stateEvents";
+    roles[AuthorListRole] = "authorList";
     return roles;
 }
 
 QString CollapseStateProxyModel::aggregateEventToString(int sourceRow) const
 {
     QStringList parts;
+    QVariantList uniqueAuthors;
     for (int i = sourceRow; i >= 0; i--) {
-        parts += sourceModel()->data(sourceModel()->index(i, 0), Qt::DisplayRole).toString();
-        if (sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::EventTypeRole)
+        parts += sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::GenericDisplayRole).toString();
+        QVariant nextAuthor = sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::AuthorRole);
+        if (!uniqueAuthors.contains(nextAuthor)) {
+            uniqueAuthors.append(nextAuthor);
+        }
+        if (sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::EventTypeRole)
                 != MessageEventModel::DelegateType::State // If it's not a state event
-            || (i > 0
-                && sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::EventResolvedTypeRole)
-                    != sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::EventResolvedTypeRole)) // or of a different type
-            || (i > 0
-                && sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::AuthorIdRole)
-                    != sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::AuthorIdRole)) // or by a different author
             || sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::ShowSectionRole).toBool() // or the section needs to be visible
         ) {
             break;
         }
     }
+    parts.sort(); // Sort them so that all identical events can be collected.
     if (!parts.isEmpty()) {
         QStringList chunks;
         while (!parts.isEmpty()) {
@@ -64,18 +66,27 @@ QString CollapseStateProxyModel::aggregateEventToString(int sourceRow) const
                 parts.removeFirst();
                 count++;
             }
-            if (count > 1) {
-                chunks.last() += i18ncp("[user did something] n times", " %1 time", " %1 times", count);
+            if (count > 1 && uniqueAuthors.length() == 1) {
+                chunks.last() += i18ncp("n times", " %1 time ", " %1 times ", count);
             }
         }
-        QString text = chunks.takeFirst();
+        chunks.removeDuplicates();
+        QString text = "<style>a {text-decoration: none;}</style>"; // There can be links in the event text so make sure all are styled.
+        // The author text is either "n users" if > 1 user or the matrix.to link to a single user.
+        QString userText = uniqueAuthors.length() > 1 ? i18ncp("n users", " %1 user ", " %1 users ", uniqueAuthors.length())
+                                                      : QStringLiteral("<a href=\"https://matrix.to/#/%1\" style=\"color: %2\">%3</a> ")
+                                                            .arg(uniqueAuthors[0].toMap()["id"].toString(),
+                                                                 uniqueAuthors[0].toMap()["color"].toString(),
+                                                                 uniqueAuthors[0].toMap()["displayName"].toString());
+        text += userText;
+        text += chunks.takeFirst();
 
         if (chunks.size() > 0) {
             while (chunks.size() > 1) {
-                text += i18nc("[action 1], [action 2 and action 3]", ", ");
+                text += i18nc("[action 1], [action 2 and/or action 3]", ", ");
                 text += chunks.takeFirst();
             }
-            text += i18nc("[action 1, action 2] and [action 3]", " and ");
+            text += uniqueAuthors.length() > 1 ? i18nc("[action 1, action 2] or [action 3]", " or ") : i18nc("[action 1, action 2] and [action 3]", " and ");
             text += chunks.takeFirst();
         }
         return text;
@@ -83,3 +94,41 @@ QString CollapseStateProxyModel::aggregateEventToString(int sourceRow) const
         return {};
     }
 }
+
+QVariantList CollapseStateProxyModel::stateEventsList(int sourceRow) const
+{
+    QVariantList stateEvents;
+    for (int i = sourceRow; i >= 0; i--) {
+        auto nextState = QVariantMap{
+            {"author", sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::AuthorRole)},
+            {"authorDisplayName", sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::AuthorDisplayNameRole).toString()},
+            {"text", sourceModel()->data(sourceModel()->index(i, 0), Qt::DisplayRole).toString()},
+        };
+        stateEvents.append(nextState);
+        if (sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::EventTypeRole)
+                != MessageEventModel::DelegateType::State // If it's not a state event
+            || sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::ShowSectionRole).toBool() // or the section needs to be visible
+        ) {
+            break;
+        }
+    }
+    return stateEvents;
+}
+
+QVariantList CollapseStateProxyModel::authorList(int sourceRow) const
+{
+    QVariantList uniqueAuthors;
+    for (int i = sourceRow; i >= 0; i--) {
+        QVariant nextAvatar = sourceModel()->data(sourceModel()->index(i, 0), MessageEventModel::AuthorRole);
+        if (!uniqueAuthors.contains(nextAvatar)) {
+            uniqueAuthors.append(nextAvatar);
+        }
+        if (sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::EventTypeRole)
+                != MessageEventModel::DelegateType::State // If it's not a state event
+            || sourceModel()->data(sourceModel()->index(i - 1, 0), MessageEventModel::ShowSectionRole).toBool() // or the section needs to be visible
+        ) {
+            break;
+        }
+    }
+    return uniqueAuthors;
+}

src/models/collapsestateproxymodel.h

@@ -12,10 +12,29 @@ class CollapseStateProxyModel : public QSortFilterProxyModel
 public:
     enum Roles {
         AggregateDisplayRole = MessageEventModel::LastRole + 1,
+        StateEventsRole,
+        AuthorListRole,
     };
     [[nodiscard]] bool filterAcceptsRow(int source_row, const QModelIndex &source_parent) const override;
     [[nodiscard]] QHash<int, QByteArray> roleNames() const override;
     [[nodiscard]] QVariant data(const QModelIndex &idx, int role = Qt::DisplayRole) const override;
 
+    /**
+     * @brief QString aggregating the text of consecutive state events starting at row.
+     *
+     * If state events happen on different days they will be split into two aggregate
+     * events.
+     */
     [[nodiscard]] QString aggregateEventToString(int row) const;
+    /**
+     * @brief Return a list of consecutive state events starting at row.
+     *
+     * If state events happen on different days they will be split into two aggregate
+     * events.
+     */
+    [[nodiscard]] QVariantList stateEventsList(int row) const;
+    /**
+     * @brief List of unique authors for the aggregate state events starting at row.
+     */
+    [[nodiscard]] QVariantList authorList(int row) const;
 };

src/models/messageeventmodel.cpp

@@ -67,6 +67,7 @@ QHash<int, QByteArray> MessageEventModel::roleNames() const
     roles[IsNameChangeRole] = "isNameChange";
     roles[IsAvatarChangeRole] = "isAvatarChange";
     roles[IsRedactedRole] = "isRedacted";
+    roles[GenericDisplayRole] = "genericDisplay";
     return roles;
 }
 
@@ -462,6 +463,14 @@ QVariant MessageEventModel::data(const QModelIndex &idx, int role) const
         return m_currentRoom->eventToString(evt, Qt::RichText);
     }
 
+    if (role == GenericDisplayRole) {
+        if (evt.isRedacted()) {
+            return i18n("<i>[This message was deleted]</i>");
+        }
+
+        return m_currentRoom->eventToGenericString(evt);
+    }
+
     if (role == FormattedBodyRole) {
         if (auto e = eventCast<const RoomMessageEvent>(&evt)) {
             if (e->hasTextContent() && e->mimeType().name() != "text/plain") {

src/models/messageeventmodel.h

@@ -45,6 +45,7 @@ public:
         AnnotationRole,
         UserMarkerRole,
         FormattedBodyRole,
+        GenericDisplayRole,
 
         MimeTypeRole,
         FileMimetypeIcon,