fix annotations issue

Author: MjnMixael

code/missioneditor/sexp_annotation_model.cpp

@@ -126,6 +126,15 @@ bool SexpAnnotationModel::isDefault(const event_annotation& ea)
 // Mutation
 // -----------------------------------------------------------------------
 
+// Remove the annotation with the given key, if one exists.
+void SexpAnnotationModel::removeByKey(int key)
+{
+	int idx = findByKey(key);
+	if (idx >= 0) {
+		m_annotations.erase(m_annotations.begin() + idx);
+	}
+}
+
 // Remove all annotations that have default values (no useful data).
 void SexpAnnotationModel::prune()
 {

code/missioneditor/sexp_annotation_model.h

@@ -56,6 +56,9 @@ class SexpAnnotationModel {
 	// Mutation
 	// ---------------------------------------------------------------
 
+	// Remove the annotation with the given key, if one exists.
+	void removeByKey(int key);
+
 	// Remove all annotations that are at default values.
 	void prune();
 

code/missioneditor/sexp_tree_model.cpp

@@ -1,4 +1,5 @@
 #include "missioneditor/sexp_tree_model.h"
+#include "missioneditor/sexp_annotation_model.h"
 
 #include "parse/sexp.h"
 #include "parse/sexp_container.h"
@@ -397,6 +398,11 @@ void SexpTreeModel::free_node2(int node)
 		*modified = 1;
 	tree_nodes[node].type = SEXPT_UNUSED;
 	total_nodes--;
+
+	// Remove any annotation referencing this node so that if allocate_node()
+	// reuses this slot, the new node won't inherit a stale annotation.
+	if (annotation_model)
+		annotation_model->removeByKey(node);
 	if (tree_nodes[node].child != -1)
 		free_node2(tree_nodes[node].child);
 

code/missioneditor/sexp_tree_model.h

@@ -8,6 +8,8 @@
 #include "globalincs/flagset.h"
 #include "globalincs/vmallocator.h"
 
+class SexpAnnotationModel;
+
 // -----------------------------------------------------------------------
 // SEXPT_* node type/status constants
 // -----------------------------------------------------------------------
@@ -440,6 +442,10 @@ class SexpTreeModel {
 	// Model code sets *modified = 1 when tree data changes.
 	int* modified;
 
+	// Optional annotation model — when set, free_node2() automatically removes
+	// annotations referencing freed nodes to prevent stale annotation reuse.
+	SexpAnnotationModel* annotation_model = nullptr;
+
 	// --- Tree navigation helpers ---
 
 	// Return the 0-based argument position of child_node among parent_node's children, or -1

fred2/eventeditor.cpp

@@ -278,6 +278,7 @@ BOOL event_editor::OnInitDialog()
 	// load event annotations into local model and apply comment icons
 	m_annotation_model.loadFromGlobal(m_event_tree._model.tree_nodes, m_events, m_sig);
 	m_event_tree.m_annotations = &m_annotation_model;
+	m_event_tree._model.annotation_model = &m_annotation_model;
 	for (auto &ea : m_annotation_model.annotations())
 	{
 		if (ea.node_index >= 0 && !ea.comment.empty())

qtfred/src/mission/dialogs/MissionEventsDialogModel.cpp

@@ -166,6 +166,7 @@ void MissionEventsDialogModel::initializeEvents()
 void MissionEventsDialogModel::initializeEventAnnotations()
 {
 	m_annotation_model.loadFromGlobal(m_tree_model.tree_nodes, m_events, m_sig);
+	m_tree_model.annotation_model = &m_annotation_model;
 
 	for (const auto& ea : m_annotation_model.annotations()) {
 		if (ea.node_index >= 0) {