Populate hidden item dropdown menu with item constants

mainwindow.cpp

     Project *project = editor->project;
     project->readMapAttributesTable();
     project->readAllMapAttributes();
+    project->readItemNames();
 }
 
 void MainWindow::populateMapList() {
                     combo->addItem(value);
                 }
                 combo->addItems(*editor->project->mapNames);
+            } else if (key == "item") {
+                if (!editor->project->itemNames->contains(value)) {
+                    combo->addItem(value);
+                }
+                combo->addItems(*editor->project->itemNames);
             } else {
                 combo->addItem(value);
             }

project.cpp

     groupNames = new QStringList;
     map_groups = new QMap<QString, int>;
     mapNames = new QStringList;
+    itemNames = new QStringList;
     map_cache = new QMap<QString, Map*>;
     mapConstantsToMapNames = new QMap<QString, QString>;
     mapNamesToMapConstants = new QMap<QString, QString>;
     return names;
 }
 
+void Project::readItemNames() {
+    QString text = readTextFile(root + "/include/constants/items.h");
+    if (!text.isNull()) {
+        QStringList itemDefinePrefixes;
+        itemDefinePrefixes << "ITEM_";
+        QMap<QString, int> itemDefines = readCDefines(text, itemDefinePrefixes);
+
+        // The item names should to be sorted by their underlying value, not alphabetically.
+        // Reverse the map and read out the resulting keys in order.
+        QMultiMap<int, QString> itemDefinesInverse;
+        for (QString itemName : itemDefines.keys()) {
+            itemDefinesInverse.insert(itemDefines[itemName], itemName);
+        }
+
+        for (int itemValue : itemDefinesInverse.keys()) {
+            QList<QString> names = itemDefinesInverse.values(itemValue);
+            for (QString name : names) {
+                itemNames->append(name);
+            }
+        }
+    }
+}
+
 QStringList Project::getSongNames() {
     QStringList names;
     QString text = readTextFile(root + "/include/constants/songs.h");

project.h

     QMap<int, QString> mapAttributesTableMaster;
     QMap<QString, QMap<QString, QString>> mapAttributes;
     QMap<QString, QMap<QString, QString>> mapAttributesMaster;
-
+    QStringList *itemNames = NULL;
 
     QMap<QString, Map*> *map_cache;
     Map* loadMap(QString);
     QStringList getWeathers();
     QStringList getMapTypes();
     QStringList getBattleScenes();
+    void readItemNames();
 
     void loadObjectPixmaps(QList<Event*> objects);
     QMap<QString, int> getMapObjGfxConstants();