Merge the functionality of CollapseStateProxyModel into MessageFilterModel

Merge the functionality of CollapseStateProxyModel into MessageFilterModel there is no need for a whole separate model the filters can be combined trivialy.

src/models/messagefiltermodel.h

@@ -5,21 +5,79 @@
 
 #include <QSortFilterProxyModel>
 
+#include "messageeventmodel.h"
+
 /**
  * @class MessageFilterModel
  *
  * This model filters out any messages that should be hidden.
  *
  * Deleted messages are only hidden if the user hasn't set them to be shown.
+ *
+ * The model also contains the roles and functions to support aggregating multiple
+ * consecutive state events into a single delegate. The state events must all happen
+ * on the same day to be aggregated.
  */
 class MessageFilterModel : public QSortFilterProxyModel
 {
     Q_OBJECT
 public:
+    /**
+     * @brief Defines the model roles.
+     */
+    enum Roles {
+        AggregateDisplayRole = MessageEventModel::LastRole + 1, /**< Single line aggregation of all the state events. */
+        StateEventsRole, /**< List of state events in the aggregated state. */
+        AuthorListRole, /**< List of the first 5 unique authors of the aggregated state event. */
+        ExcessAuthorsRole, /**< The number of unique authors beyond the first 5. */
+        LastRole, // Keep this last
+    };
+
     explicit MessageFilterModel(QObject *parent = nullptr);
 
     /**
      * @brief Custom filter function to remove hidden messages.
      */
     bool filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const override;
+
+    /**
+     * @brief Get the given role value at the given index.
+     *
+     * @sa QSortFilterProxyModel::data
+     */
+    [[nodiscard]] QVariant data(const QModelIndex &idx, int role = Qt::DisplayRole) const override;
+
+    /**
+     * @brief Returns a mapping from Role enum values to role names.
+     *
+     * @sa Roles, QAbstractProxyModel::roleNames()
+     */
+    [[nodiscard]] QHash<int, QByteArray> roleNames() const override;
+
+private:
+    /**
+     * @brief Aggregation of 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 the first 5 unique authors for the aggregate state events starting at row.
+     */
+    [[nodiscard]] QVariantList authorList(int row) const;
+
+    /**
+     * @brief The number of unique authors beyond the first 5 for the aggregate state events starting at row.
+     */
+    [[nodiscard]] QString excessAuthors(int row) const;
 };