Fix retain cycles

src/service/repository.vala

@@ -24,6 +24,8 @@ public class Repository : DBusServiceProxy {
     }
 
     private void connect_to_repository() {
+        GLib.info("Connecting to repository");
+
         try {
             this.dbus_repository = Bus.get_proxy_sync<DBusService.Repository>(BusType.SESSION, DBUS_NAME, DBUS_PATH);
             this.dbus_repository.conversations_updated.connect(() => {

src/transcript/message-list-model.vala

@@ -5,8 +5,8 @@ public class MessageListModel : Object, ListModel
 {
     public signal void messages_changed();
 
-    public SortedSet<Message> messages {
-        owned get { return _messages.read_only_view; }
+    public ArrayList<Message> messages {
+        get { return _messages; }
     }
 
     public bool is_group_chat {
@@ -17,19 +17,34 @@ public class MessageListModel : Object, ListModel
 
     public string conversation_guid { get; private set; }
 
-    private SortedSet<Message> _messages;
+    private ArrayList<Message> _messages;
     private HashSet<string> participants = new HashSet<string>();
+    private ulong handler_id = 0;
 
     public MessageListModel(string conversation_guid) {
-        _messages = new TreeSet<Message>((a, b) => {
-            // Sort by date in descending order (newest first)
-            return a.date.compare(b.date);
-        });
-
-        Repository.get_instance().messages_updated.connect(got_messages_updated);
+        _messages = new ArrayList<Message>();
         this.conversation_guid = conversation_guid;
     }
 
+    ~MessageListModel() {
+        // NOTE: this won't actually get destructed automatically because of a retain cycle with the signal handler. 
+        // unwatch_updates() should be called explicitly when the model is no longer needed.
+        unwatch_updates();
+    }
+
+    public void watch_updates() {
+        if (this.handler_id == 0) {
+            this.handler_id = Repository.get_instance().messages_updated.connect(got_messages_updated);
+        }
+    }
+
+    public void unwatch_updates() {
+        if (this.handler_id != 0) {
+            Repository.get_instance().disconnect(this.handler_id);
+            this.handler_id = 0;
+        }
+    }
+
     public void load_messages() {
         try {
             Message[] messages = Repository.get_instance().get_messages(conversation_guid);
@@ -82,6 +97,6 @@ public class MessageListModel : Object, ListModel
     }
     
     public Object? get_item(uint position) {
-        return _messages.to_array()[position];
+        return _messages.get((int)position);
     }
 }

src/transcript/transcript-drawing-area.vala

@@ -5,7 +5,7 @@ private class TranscriptDrawingArea : Widget
 {
     public bool show_sender = true;
 
-    private SortedSet<Message> _messages = new TreeSet<Message>();
+    private ArrayList<Message> _messages = new ArrayList<Message>();
     private ArrayList<ChatItemLayout> _chat_items = new ArrayList<ChatItemLayout>();
 
     private const float bubble_margin = 18.0f;
@@ -14,7 +14,7 @@ private class TranscriptDrawingArea : Widget
         add_css_class("transcript-drawing-area");
     }
 
-    public void set_messages(SortedSet<Message> messages) {
+    public void set_messages(ArrayList<Message> messages) {
         _messages = messages;
         recompute_message_layouts();
     }

src/transcript/transcript-view.vala

@@ -9,16 +9,25 @@ public class TranscriptView : Adw.Bin
             return _model;
         }
         set {
+            if (_model != null) {
+                _model.disconnect(messages_changed_handler_id);
+                _model.unwatch_updates();
+            }
+
             _model = value;
 
-            if (model != null) {
+            if (value != null) {
                 // Reset scroll position
                 scrolled_window.vadjustment = new Gtk.Adjustment(0, 0, 0, 0, 0, 0);
 
-                model.messages_changed.connect(reload_messages);
-                model.load_messages();
+                weak TranscriptView self = this;
+                messages_changed_handler_id = value.messages_changed.connect(() => {
+                    self.reload_messages();
+                });
+
+                value.load_messages();
             } else {
-                transcript_drawing_area.set_messages(new TreeSet<Message>());
+                transcript_drawing_area.set_messages(new ArrayList<Message>());
             }
         }
     }
@@ -34,10 +43,9 @@ public class TranscriptView : Adw.Bin
 
     private TranscriptDrawingArea transcript_drawing_area = new TranscriptDrawingArea();
     private ScrolledWindow scrolled_window = new ScrolledWindow();
+    private ulong messages_changed_handler_id = 0;
 
-    public TranscriptView(MessageListModel? model = null) {
-        this.model = model;
-
+    public TranscriptView() {
         container = new Adw.ToolbarView();
         set_child(container);