From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: MrHua269 <novau233@163.com>
Date: Fri, 12 Apr 2024 13:48:09 +0000
Subject: [PATCH] Rewrite linear region flush task dispatching


diff --git a/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFile.java b/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFile.java
index e40989889f3821bb7484fc0bae5d94b033013904..dc5a5f42c9ca7a50295c18424722568a3ad33fa5 100644
--- a/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFile.java
+++ b/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFile.java
@@ -126,7 +126,7 @@ public class LinearRegionFile implements AbstractRegionFile, AutoCloseable {
     }
 
     public void flush() throws IOException {
-        if (isMarkedToSave()) flushWrapper(); // sync
+        if (getAndResetSaveMarker()) flushWrapper(); // sync
     }
 
     private void markToSave() {
@@ -134,10 +134,18 @@ public class LinearRegionFile implements AbstractRegionFile, AutoCloseable {
         markedToSave.set(true);
     }
 
-    public boolean isMarkedToSave() {
+    public boolean getAndResetSaveMarker() {
         return markedToSave.getAndSet(false);
     }
 
+    public boolean isMarkedToSave(){
+        return this.markedToSave.get();
+    }
+
+    public void resetSaveMarker(){
+        this.markedToSave.set(false);
+    }
+
     public void flushWrapper() {
         try {
             save();
diff --git a/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFileFlusher.java b/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFileFlusher.java
index f06d7767c79e465f999b2032086cc224de95152a..65435eb666b2e1cabffc145e016faa5e3b373464 100644
--- a/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFileFlusher.java
+++ b/src/main/java/dev/kaiijumc/kaiiju/region/LinearRegionFileFlusher.java
@@ -1,17 +1,14 @@
 package dev.kaiijumc.kaiiju.region;
 
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
-import java.util.Queue;
+
+import java.util.Set;
 import java.util.concurrent.*;
 import org.bukkit.Bukkit;
 
 public class LinearRegionFileFlusher {
-    private final Queue<LinearRegionFile> savingQueue = new LinkedBlockingQueue<>();
-    private final ScheduledExecutorService scheduler = Executors.newSingleThreadScheduledExecutor(
-        new ThreadFactoryBuilder()
-            .setNameFormat("linear-flush-scheduler")
-            .build()
-    );
+    private final Set<LinearRegionFile> pendingSaving = ConcurrentHashMap.newKeySet();
+
     private final ExecutorService executor = Executors.newFixedThreadPool(
         me.earthme.luminol.config.modules.misc.RegionFormatConfig.linearFlushThreads,
         new ThreadFactoryBuilder()
@@ -19,26 +16,42 @@ public class LinearRegionFileFlusher {
             .build()
     );
 
+    private final Executor delayedFlusher = CompletableFuture.delayedExecutor(
+            me.earthme.luminol.config.modules.misc.RegionFormatConfig.linearFlushFrequency,
+            TimeUnit.SECONDS,
+            executor
+    );
+
     public LinearRegionFileFlusher() {
         Bukkit.getLogger().info("Using " + me.earthme.luminol.config.modules.misc.RegionFormatConfig.linearFlushThreads + " threads for linear region flushing.");
-        scheduler.scheduleAtFixedRate(this::pollAndFlush, 0L, me.earthme.luminol.config.modules.misc.RegionFormatConfig.linearFlushFrequency, TimeUnit.SECONDS);
     }
 
     public void scheduleSave(LinearRegionFile regionFile) {
-        if (savingQueue.contains(regionFile)) return;
-        savingQueue.add(regionFile);
-    }
-
-    private void pollAndFlush() {
-        while (!savingQueue.isEmpty()) {
-            LinearRegionFile regionFile = savingQueue.poll();
-            if (!regionFile.closed && regionFile.isMarkedToSave())
-                executor.execute(regionFile::flushWrapper);
+        if (this.pendingSaving.contains(regionFile) || !regionFile.isMarkedToSave()){
+            return;
         }
+
+        this.pendingSaving.add(regionFile);
+        this.delayedFlusher.execute(()->{
+            try {
+                if (!regionFile.closed && regionFile.isMarkedToSave()){
+                    regionFile.flushWrapper();
+                }
+            }finally {
+                regionFile.resetSaveMarker();
+                this.pendingSaving.remove(regionFile);
+            }
+        });
     }
 
     public void shutdown() {
-        executor.shutdown();
-        scheduler.shutdown();
+        this.executor.shutdown();
+        for (;;) {
+            try {
+                if (this.executor.awaitTermination(5_00,TimeUnit.MILLISECONDS)) break;
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
     }
 }