fix: Hierarchy now updates properly

editor/explorermodel.cpp

@@ -3,12 +3,35 @@
 #include "qcontainerfwd.h"
 #include "qobject.h"
 #include "qwidget.h"
+#include "common.h"
+#include <algorithm>
+#include <optional>
 
 // https://doc.qt.io/qt-6/qtwidgets-itemviews-simpletreemodel-example.html#testing-the-model
 
 ExplorerModel::ExplorerModel(InstanceRef dataRoot, QWidget *parent)
     : QAbstractItemModel(parent)
     , rootItem(dataRoot) {
+    // TODO: Don't use lambdas and handlers like that
+    hierarchyPreUpdateHandler = [&](InstanceRef object, std::optional<InstanceRef> oldParent, std::optional<InstanceRef> newParent) {
+        if (oldParent.has_value()) {
+            auto children = oldParent.value()->GetChildren();
+            size_t idx = std::find(children.begin(), children.end(), object) - children.end();
+            beginRemoveRows(toIndex(oldParent.value()), idx, idx);
+        }
+
+        if (newParent.has_value()) {
+            size_t size = newParent.value()->GetChildren().size();
+            beginInsertRows(toIndex(newParent.value()), size, size);
+        } else {
+            // TODO:
+        }
+    };
+
+    hierarchyPostUpdateHandler = [&](InstanceRef object, std::optional<InstanceRef> oldParent, std::optional<InstanceRef> newParent) {
+        if (newParent.has_value()) endInsertRows();
+        if (oldParent.has_value()) endRemoveRows();
+    };
 }
 
 ExplorerModel::~ExplorerModel() = default;
@@ -26,6 +49,18 @@ QModelIndex ExplorerModel::index(int row, int column, const QModelIndex &parent)
     return {};
 }
 
+QModelIndex ExplorerModel::toIndex(InstanceRef item) {
+    if (item == rootItem)
+        return {};
+
+    InstanceRef parentItem = item->GetParent().value();
+    // Check above ensures this item is not root, so value() must be valid
+    for (int i = 0; i < parentItem->GetChildren().size(); i++)
+        if (parentItem->GetChildren()[i] == item)
+            return createIndex(i, 0, item.get());
+    return QModelIndex{};
+}
+
 QModelIndex ExplorerModel::parent(const QModelIndex &index) const {
     if (!index.isValid())
         return {};

editor/explorermodel.h

@@ -29,6 +29,7 @@ public:
 
 private:
     InstanceRef rootItem;
+    QModelIndex toIndex(InstanceRef item);
 };
 
 #endif // EXPLORERMODEL_H

editor/mainwindow.cpp

@@ -8,6 +8,8 @@
 #include <QTimerEvent>
 #include <QMouseEvent>
 #include <QWidget>
+#include <QTreeView>
+#include <QAbstractItemView>
 #include <memory>
 
 #include "common.h"

src/common.cpp

@@ -5,4 +5,6 @@
 
 Camera camera(glm::vec3(0.0, 0.0, 3.0));
 //std::vector<Part> parts;
-std::shared_ptr<Workspace> workspace = Workspace::New();
+std::shared_ptr<Workspace> workspace = Workspace::New();
+std::optional<HierarchyPreUpdateHandler> hierarchyPreUpdateHandler;
+std::optional<HierarchyPostUpdateHandler> hierarchyPostUpdateHandler;

src/common.h

@@ -1,8 +1,17 @@
 #pragma once
 #include "objects/workspace.h"
 #include "camera.h"
+#include <functional>
+#include <memory>
+
+class Instance;
+// typedef std::function<void(std::shared_ptr<Instance> element, std::optional<std::shared_ptr<Instance>> newParent)> HierarchyUpdateHandler;
+typedef std::function<void(InstanceRef object, std::optional<InstanceRef> oldParent, std::optional<InstanceRef> newParent)> HierarchyPreUpdateHandler;
+typedef std::function<void(InstanceRef object, std::optional<InstanceRef> oldParent, std::optional<InstanceRef> newParent)> HierarchyPostUpdateHandler;
 
 // TEMPORARY COMMON DATA FOR DIFFERENT INTERNAL COMPONENTS
 
 extern Camera camera;
-extern std::shared_ptr<Workspace> workspace;
+extern std::shared_ptr<Workspace> workspace;
+extern std::optional<HierarchyPreUpdateHandler> hierarchyPreUpdateHandler;
+extern std::optional<HierarchyPostUpdateHandler> hierarchyPostUpdateHandler;

src/objects/base/instance.cpp

@@ -1,4 +1,5 @@
 #include "instance.h"
+#include "../../common.h"
 #include <algorithm>
 #include <memory>
 #include <optional>
@@ -25,6 +26,8 @@ Instance::~Instance () {
 }
 
 void Instance::SetParent(std::optional<std::shared_ptr<Instance>> newParent) {
+    auto lastParent = GetParent();
+    if (hierarchyPreUpdateHandler.has_value()) hierarchyPreUpdateHandler.value()(this->shared_from_this(), lastParent, newParent);
     // If we currently have a parent, remove ourselves from it before adding ourselves to the new one
     if (this->parent.has_value() && !this->parent.value().expired()) {
         auto oldParent = this->parent.value().lock();
@@ -36,6 +39,8 @@ void Instance::SetParent(std::optional<std::shared_ptr<Instance>> newParent) {
     }
     this->parent = newParent;
     // TODO: Add code for sending signals for parent updates
+    // TODO: Yeahhh maybe this isn't the best way of doing this?
+    if (hierarchyPostUpdateHandler.has_value()) hierarchyPostUpdateHandler.value()(this->shared_from_this(), lastParent, newParent);
 }
 
 std::optional<std::shared_ptr<Instance>> Instance::GetParent() {