Merge pull request #5320 from SiliconSaga/review/post-di-phase4

review: remove null CoreRegistry, guard null binds/providers, fix Mermaid

Author: Cervator

docs/EngineStartUp/Engine-States.md

@@ -20,8 +20,8 @@ graph TD;
     subgraph Loading
         subgraph LoadingUpdate[Update]
             LoadingLoadingScreenUpdate[LoadingScreen::updateStatus] --> LoadingNUIManagerUpdate[NUIManager]
-            LoadingNUIManagerUpdate--> LoadingStepUpdate[Step Update]
-            subgraph LoadingStepUpdate
+            LoadingNUIManagerUpdate--> LoadingStepUpdate
+            subgraph LoadingStepUpdate[Step Update]
                 direction TB
                 RegisterMods --> InitRenderingHeadlessCheck{!headless}
                 InitRenderingHeadlessCheck -->|true| InitialiseRendering --> InitialiseEntitySystem

engine/src/main/java/org/terasology/engine/core/TerasologyEngine.java

@@ -182,13 +182,8 @@ public TerasologyEngine(TimeSubsystem timeSubsystem, Collection<EngineSubsystem>
         rootContextRegistry.with(CharacterStateEventPositionMap.class).lifetime(Lifetime.Singleton).use(() -> characterStateEventPositionMap);
         DirectionAndOriginPosRecorderList directionAndOriginPosRecorderList = new DirectionAndOriginPosRecorderList();
         rootContextRegistry.with(DirectionAndOriginPosRecorderList.class).lifetime(Lifetime.Singleton).use(() -> directionAndOriginPosRecorderList);
-        /*
-         * We can't load the engine without core registry yet.
-         * e.g. the statically created MaterialLoader needs the CoreRegistry to get the AssetManager.
-         * And the engine loads assets while it gets created.
-         */
-        // TODO: Remove
-        CoreRegistry.setContext(rootContext);
+        // Clear any stale context — rootContext is set in initialize().
+        CoreRegistry.setContext(null);
 
         this.allSubsystems = Queues.newArrayDeque();
         configurationSubsystem = new ConfigurationSubsystem();

engine/src/main/java/org/terasology/engine/core/subsystem/config/BindsSubsystem.java

@@ -420,11 +420,11 @@ public List<Input> getInputsForBindButton(SimpleUri bindId) {
             }
         }
 
-        if (mouseWheelUpBind.getId().equals(bindId)) {
+        if (mouseWheelUpBind != null && mouseWheelUpBind.getId().equals(bindId)) {
             inputs.add(MouseInput.WHEEL_UP);
         }
 
-        if (mouseWheelDownBind.getId().equals(bindId)) {
+        if (mouseWheelDownBind != null && mouseWheelDownBind.getId().equals(bindId)) {
             inputs.add(MouseInput.WHEEL_DOWN);
         }
 

engine/src/main/java/org/terasology/engine/persistence/internal/ReadWriteStorageManager.java

@@ -267,11 +267,19 @@ private void waitForCompletionOfPreviousSave() {
     }
 
     private SaveTransaction createSaveTransaction() {
+        ChunkProvider chunkProviderInstance = chunkProvider != null ? chunkProvider.get() : null;
+        NetworkSystem networkSystemInstance = networkSystem != null ? networkSystem.get() : null;
+        if (chunkProviderInstance == null) {
+            throw new IllegalStateException("Cannot save: ChunkProvider not available");
+        }
+        if (networkSystemInstance == null) {
+            throw new IllegalStateException("Cannot save: NetworkSystem not available");
+        }
         SaveTransactionBuilder saveTransactionBuilder = new SaveTransactionBuilder(privateEntityManager,
                 entitySetDeltaRecorder, isStoreChunksInZips(), getStoragePathProvider(), worldDirectoryWriteLock,
                 recordAndReplaySerializer, recordAndReplayUtils, recordAndReplayCurrentStatus);
-        addChunksToSaveTransaction(saveTransactionBuilder, chunkProvider.get());
-        addPlayersToSaveTransaction(saveTransactionBuilder, networkSystem.get());
+        addChunksToSaveTransaction(saveTransactionBuilder, chunkProviderInstance);
+        addPlayersToSaveTransaction(saveTransactionBuilder, networkSystemInstance);
         addGlobalStoreBuilderToSaveTransaction(saveTransactionBuilder);
         addGameManifestToSaveTransaction(saveTransactionBuilder);
 
@@ -403,9 +411,13 @@ public void update() {
     }
 
     private boolean isRunModeAllowSaving() {
+        if (networkSystem == null || chunkProvider == null) {
+            return false;
+        }
         NetworkSystem networkSystemInstance = networkSystem.get();
-        return networkSystemInstance != null && networkSystemInstance.getMode().isAuthority() && chunkProvider.get() != null
-                && blockManager != null;
+        ChunkProvider chunkProviderInstance = chunkProvider.get();
+        return networkSystemInstance != null && networkSystemInstance.getMode().isAuthority()
+                && chunkProviderInstance != null && blockManager != null;
     }
 
     private void startSaving() {