From 881f71611561cda96e20930a7ff9a15ad5db1333 Mon Sep 17 00:00:00 2001
From: George <george@me.com>
Date: Sun, 7 Jun 2026 16:42:11 +0100
Subject: [PATCH] Fix two live simulation bugs: profiler crash + regions never
 updating
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forceUpdateRegion crashed with "no profiling cycle is active" because
runModulesForRegion calls profiler.beginModule() which requires an active
cycle. Wrapped the call in startCycle/endCycle in a try/finally.

Regions showed tick=0 and no module data because SimulationScheduler's
priority queue was never populated for normal rolling updates — only
explicit queueRegion() calls worked. Fixed by auto-enqueueing all active
regions in onMinecraftServerTick() just before each simulation cycle fires.
Auto-enqueueing is placed there (not in runSimulationCycle()) so unit tests
that drive cycles directly are unaffected.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 .../core/simulation/RegionManager.java          |  8 +++++++-
 .../core/simulation/SimulationManager.java      | 17 ++++++++++++++++-
 .../core/simulation/SimulationManagerTest.java  |  5 +++++
 .../testing/LongRunSimulationTest.java          |  5 +++++
 4 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/src/main/java/com/livingworld/core/simulation/RegionManager.java b/src/main/java/com/livingworld/core/simulation/RegionManager.java
index 671d1b6..6952119 100644
--- a/src/main/java/com/livingworld/core/simulation/RegionManager.java
+++ b/src/main/java/com/livingworld/core/simulation/RegionManager.java
@@ -1,5 +1,6 @@
 package com.livingworld.core.simulation;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
 
@@ -30,9 +31,14 @@ public interface RegionManager {
      */
     List<Region> resolveAll(List<RegionCoordinate> coordinates);
 
+    /**
+     * Returns all currently active (cached/loaded) regions.
+     */
+    Collection<Region> getActiveRegions();
+
     /**
      * Marks a region as dirty, indicating unsaved changes.
-     * 
+     *
      * @param region the region to mark dirty (must not be null)
      */
     void markDirty(Region region);
diff --git a/src/main/java/com/livingworld/core/simulation/SimulationManager.java b/src/main/java/com/livingworld/core/simulation/SimulationManager.java
index 24ad402..bbb9d09 100644
--- a/src/main/java/com/livingworld/core/simulation/SimulationManager.java
+++ b/src/main/java/com/livingworld/core/simulation/SimulationManager.java
@@ -1,5 +1,6 @@
 package com.livingworld.core.simulation;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
 import java.util.Set;
@@ -63,6 +64,11 @@ public final class SimulationManager {
         this.scheduler.onMinecraftTick();
 
         if (this.scheduler.shouldRunSimulationCycle()) {
+            long tick = this.timeService.getSimulationTick();
+            for (Region r : this.regionManager.getActiveRegions()) {
+                this.scheduler.queueRegion(new RegionUpdateJob(
+                        r.getCoordinate(), 0, tick, null, UpdateReason.NORMAL_ROLLING_UPDATE));
+            }
             runSimulationCycle();
         }
     }
@@ -209,7 +215,16 @@ public final class SimulationManager {
         long tick = getSimulationTickCounter();
         RegionUpdateJob job = new RegionUpdateJob(
                 coordinate, 100, tick, null, UpdateReason.FORCED_DEBUG_COMMAND);
-        runModulesForRegion(region.get(), job, tick);
+        if (this.profiler != null) {
+            this.profiler.startCycle(tick);
+        }
+        try {
+            runModulesForRegion(region.get(), job, tick);
+        } finally {
+            if (this.profiler != null) {
+                this.profiler.endCycle(0);
+            }
+        }
     }
 
     /** Returns a profile snapshot of the last completed simulation cycle. */
diff --git a/src/test/java/com/livingworld/core/simulation/SimulationManagerTest.java b/src/test/java/com/livingworld/core/simulation/SimulationManagerTest.java
index 7a8502a..fbeea87 100644
--- a/src/test/java/com/livingworld/core/simulation/SimulationManagerTest.java
+++ b/src/test/java/com/livingworld/core/simulation/SimulationManagerTest.java
@@ -233,6 +233,11 @@ class SimulationManagerTest {
             return coordinates.stream().map(regions::get).filter(java.util.Objects::nonNull).toList();
         }
 
+        @Override
+        public java.util.Collection<Region> getActiveRegions() {
+            return regions.values();
+        }
+
         @Override
         public void markDirty(Region region) {
             markDirtyCount++;
diff --git a/src/test/java/com/livingworld/testing/LongRunSimulationTest.java b/src/test/java/com/livingworld/testing/LongRunSimulationTest.java
index 948f19c..5a8c047 100644
--- a/src/test/java/com/livingworld/testing/LongRunSimulationTest.java
+++ b/src/test/java/com/livingworld/testing/LongRunSimulationTest.java
@@ -158,6 +158,11 @@ class LongRunSimulationTest {
                     .toList();
         }
 
+        @Override
+        public Collection<Region> getActiveRegions() {
+            return orderedRegions;
+        }
+
         @Override
         public void markDirty(Region region) {
             region.markDirty();