From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Ivan Pekov <ivan@mrivanplays.com>
Date: Sun, 27 Sep 2020 18:30:10 +0300
Subject: [PATCH] Add last tick time API

Original code by YatopiaMC, licensed under MIT
You can find the original code on https://github.com/YatopiaMC/Yatopia

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 7ace6c1e81519b3e4f673d23627ca603fecb646d..3378298b0c465c0df9618804c390930e875bcce3 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1095,6 +1095,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     // Spigot End
 
     public static volatile RuntimeException chunkSystemCrash; // Paper - rewrite chunk system
+    public static java.time.Duration lastTickTime = java.time.Duration.ZERO; // Yatopia
 
     protected void runServer() {
         try {
@@ -1172,7 +1173,9 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                 this.nextTickTime += 50L;
                 this.startMetricsRecordingTick();
                 this.profiler.push("tick");
+                long tickStart = System.nanoTime(); // Yatopia
                 this.tickServer(this::haveTime);
+                lastTickTime = java.time.Duration.ofNanos(System.nanoTime() - tickStart); // Yatopia
                 this.profiler.popPush("nextTickWait");
                 this.mayHaveDelayedTasks = true;
                 this.delayedTasksMaxNextTickTime = Math.max(Util.getMillis() + 50L, this.nextTickTime);
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index adf6308c0d8dbd8919db60abce51082091005bd1..f6f15f1913b558b457e6e63db93cb0f9c1b6724d 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -2914,6 +2914,12 @@ public final class CraftServer implements Server {
     public CraftPotionBrewer getPotionBrewer() {
         return this.potionBrewer;
     }
-
     // Paper end
+
+    // Yatopia start
+    @Override
+    public java.time.Duration getLastTickTime() {
+        return net.minecraft.server.MinecraftServer.lastTickTime;
+    }
+    // Yatopia end
 }
diff --git a/src/main/java/org/spigotmc/TicksPerSecondCommand.java b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
index 9bede6a26c08ede063c7a38f1149c811df14b258..b735769b7876e54db2950ebb4170484447cfb9a6 100644
--- a/src/main/java/org/spigotmc/TicksPerSecondCommand.java
+++ b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
@@ -32,6 +32,10 @@ public class TicksPerSecondCommand extends Command
             tpsAvg[i] = TicksPerSecondCommand.format( tps[i] );
         }
         sender.sendMessage(ChatColor.GOLD + "TPS from last 1m, 5m, 15m: " + org.apache.commons.lang.StringUtils.join(tpsAvg, ", "));
+        // Yatopia start - Last tick time API
+        java.time.Duration lastTickTime = org.bukkit.Bukkit.getLastTickTime();
+        sender.sendMessage(ChatColor.GOLD + "Last tick: " + TicksPerSecondCommand.formatTo( lastTickTime, java.util.concurrent.TimeUnit.MILLISECONDS ) + " (" + formatTo( lastTickTime, java.util.concurrent.TimeUnit.NANOSECONDS ) + ")");
+        // Yatopia end
         if (args.length > 0 && args[0].equals("mem") && sender.hasPermission("bukkit.command.tpsmemory")) {
             sender.sendMessage(ChatColor.GOLD + "Current Memory Usage: " + ChatColor.GREEN + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) / (1024 * 1024)) + "/" + (Runtime.getRuntime().totalMemory() / (1024 * 1024)) + " mb (Max: " + (Runtime.getRuntime().maxMemory() / (1024 * 1024)) + " mb)");
             if (!hasShownMemoryWarning) {
@@ -50,4 +54,15 @@ public class TicksPerSecondCommand extends Command
         return ( ( tps > 18.0 ) ? ChatColor.GREEN : ( tps > 16.0 ) ? ChatColor.YELLOW : ChatColor.RED ).toString()
                 + ( ( tps > 21.0 ) ? "*" : "" ) + Math.min( Math.round( tps * 100.0 ) / 100.0, 20.0 ); // Paper - only print * at 21, we commonly peak to 20.02 as the tick sleep is not accurate enough, stop the noise
     }
+
+    // Yatopia start - Last tick time API
+    public static String formatTo(java.time.Duration duration, java.util.concurrent.TimeUnit unit) {
+        java.util.concurrent.TimeUnit nanosUnit = java.util.concurrent.TimeUnit.NANOSECONDS;
+        long nanos = duration.toNanos();
+        long toAskedUnit = unit.convert( nanos, nanosUnit );
+        long ms = nanosUnit.toMillis( nanos );
+        ChatColor startingColor = ms < 40 ? ChatColor.GREEN : ( ms < 50 ) ? ChatColor.YELLOW : ChatColor.RED;
+        return startingColor.toString() + toAskedUnit + ChatColor.GOLD + org.yatopiamc.yatopia.server.util.TimeUtils.getFriendlyName( unit );
+    }
+    // Yatopia end
 }