From 2a3732fa83d122894c6880cb5c65563b76e9e2ec Mon Sep 17 00:00:00 2001
From: Tofaa2 <tofik.adigozalov@gmail.com>
Date: Mon, 10 Jun 2024 17:23:54 +0400
Subject: [PATCH] Fix holograms

---
 .idea/workspace.xml                           | 130 ++++++++----------
 .../java/me/tofaa/entitylib/utils/Check.java  |  13 ++
 .../entitylib/wrapper/hologram/Hologram.java  |  30 ++--
 .../wrapper/hologram/LegacyHologram.java      |  15 +-
 .../wrapper/hologram/ModernHologram.java      |  28 +++-
 test-plugin/build.gradle                      |   2 +-
 .../testentitylib/TestEntityLibPlugin.java    |   1 +
 .../testentitylib/TestHologramsCommand.java   |  48 +++++++
 8 files changed, 170 insertions(+), 97 deletions(-)
 create mode 100644 test-plugin/src/main/java/me/tofaa/testentitylib/TestHologramsCommand.java

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index d493ce1..4d8c3df 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -5,7 +5,14 @@
   </component>
   <component name="ChangeListManager">
     <list default="true" id="9d5d9b6f-43c8-41a4-bb42-a66ffc96c9b0" name="Changes" comment="">
+      <change afterPath="$PROJECT_DIR$/test-plugin/src/main/java/me/tofaa/testentitylib/TestHologramsCommand.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/utils/Check.java" beforeDir="false" afterPath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/utils/Check.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java" beforeDir="false" afterPath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java" beforeDir="false" afterPath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java" beforeDir="false" afterPath="$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/test-plugin/build.gradle" beforeDir="false" afterPath="$PROJECT_DIR$/test-plugin/build.gradle" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java" beforeDir="false" afterPath="$PROJECT_DIR$/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -34,37 +41,7 @@
         </task>
         <projects_view>
           <tree_state>
-            <expand>
-              <path>
-                <item name="" type="6a2764b6:ExternalProjectsStructure$RootNode" />
-                <item name="EntityLib" type="f1a62948:ProjectNode" />
-              </path>
-              <path>
-                <item name="" type="6a2764b6:ExternalProjectsStructure$RootNode" />
-                <item name="EntityLib" type="f1a62948:ProjectNode" />
-                <item name="test-plugin" type="2d1252cf:ModuleNode" />
-              </path>
-              <path>
-                <item name="" type="6a2764b6:ExternalProjectsStructure$RootNode" />
-                <item name="EntityLib" type="f1a62948:ProjectNode" />
-                <item name="test-plugin" type="2d1252cf:ModuleNode" />
-                <item name="Tasks" type="e4a08cd1:TasksNode" />
-              </path>
-              <path>
-                <item name="" type="6a2764b6:ExternalProjectsStructure$RootNode" />
-                <item name="EntityLib" type="f1a62948:ProjectNode" />
-                <item name="test-plugin" type="2d1252cf:ModuleNode" />
-                <item name="Tasks" type="e4a08cd1:TasksNode" />
-                <item name="run paper" type="c8890929:TasksNode$1" />
-              </path>
-              <path>
-                <item name="" type="6a2764b6:ExternalProjectsStructure$RootNode" />
-                <item name="EntityLib" type="f1a62948:ProjectNode" />
-                <item name="test-plugin" type="2d1252cf:ModuleNode" />
-                <item name="Tasks" type="e4a08cd1:TasksNode" />
-                <item name="run task shared" type="c8890929:TasksNode$1" />
-              </path>
-            </expand>
+            <expand />
             <select />
           </tree_state>
         </projects_view>
@@ -106,51 +83,51 @@
     <option name="showExcludedFiles" value="false" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent">{
-  &quot;keyToString&quot;: {
-    &quot;Downloaded.Files.Path.Enabled&quot;: &quot;false&quot;,
-    &quot;Gradle.Build EntityLib.executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib [dependencies].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib [publish].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib [runServer] (1).executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib [runServer].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:code-gen [:code-gen:Main.main()].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [cleanAllRunTaskCaches].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [cleanCustomServiceCaches].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [cleanPaperCache].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [cleanPaperPluginsCache].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [publish].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [runServer].executor&quot;: &quot;Run&quot;,
-    &quot;Gradle.EntityLib:test-plugin [shadowJar].executor&quot;: &quot;Run&quot;,
-    &quot;JAR Application.Unnamed.executor&quot;: &quot;Run&quot;,
-    &quot;Repository.Attach.Annotations&quot;: &quot;false&quot;,
-    &quot;Repository.Attach.JavaDocs&quot;: &quot;false&quot;,
-    &quot;Repository.Attach.Sources&quot;: &quot;false&quot;,
-    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
-    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
-    &quot;WebServerToolWindowFactoryState&quot;: &quot;false&quot;,
-    &quot;git-widget-placeholder&quot;: &quot;master&quot;,
-    &quot;ignore.virus.scanning.warn.message&quot;: &quot;true&quot;,
-    &quot;jdk.selected.JAVA_MODULE&quot;: &quot;corretto-17&quot;,
-    &quot;kotlin-language-version-configured&quot;: &quot;true&quot;,
-    &quot;last_opened_file_path&quot;: &quot;/home/tofaa/Github/EntityLib/model-engine-addon&quot;,
-    &quot;node.js.detected.package.eslint&quot;: &quot;true&quot;,
-    &quot;node.js.detected.package.tslint&quot;: &quot;true&quot;,
-    &quot;node.js.selected.package.eslint&quot;: &quot;(autodetect)&quot;,
-    &quot;node.js.selected.package.tslint&quot;: &quot;(autodetect)&quot;,
-    &quot;nodejs_package_manager_path&quot;: &quot;npm&quot;,
-    &quot;project.structure.last.edited&quot;: &quot;Modules&quot;,
-    &quot;project.structure.proportion&quot;: &quot;0.15&quot;,
-    &quot;project.structure.side.proportion&quot;: &quot;0.2&quot;,
-    &quot;settings.editor.selected.configurable&quot;: &quot;preferences.editor&quot;,
-    &quot;vue.rearranger.settings.migration&quot;: &quot;true&quot;
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "Downloaded.Files.Path.Enabled": "false",
+    "Gradle.Build EntityLib.executor": "Run",
+    "Gradle.EntityLib [dependencies].executor": "Run",
+    "Gradle.EntityLib [publish].executor": "Run",
+    "Gradle.EntityLib [runServer] (1).executor": "Run",
+    "Gradle.EntityLib [runServer].executor": "Run",
+    "Gradle.EntityLib:code-gen [:code-gen:Main.main()].executor": "Run",
+    "Gradle.EntityLib:test-plugin [cleanAllRunTaskCaches].executor": "Run",
+    "Gradle.EntityLib:test-plugin [cleanCustomServiceCaches].executor": "Run",
+    "Gradle.EntityLib:test-plugin [cleanPaperCache].executor": "Run",
+    "Gradle.EntityLib:test-plugin [cleanPaperPluginsCache].executor": "Run",
+    "Gradle.EntityLib:test-plugin [publish].executor": "Run",
+    "Gradle.EntityLib:test-plugin [runServer].executor": "Run",
+    "Gradle.EntityLib:test-plugin [shadowJar].executor": "Run",
+    "JAR Application.Unnamed.executor": "Run",
+    "Repository.Attach.Annotations": "false",
+    "Repository.Attach.JavaDocs": "false",
+    "Repository.Attach.Sources": "false",
+    "RunOnceActivity.OpenProjectViewOnStart": "true",
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "WebServerToolWindowFactoryState": "false",
+    "git-widget-placeholder": "master",
+    "ignore.virus.scanning.warn.message": "true",
+    "jdk.selected.JAVA_MODULE": "corretto-17",
+    "kotlin-language-version-configured": "true",
+    "last_opened_file_path": "D:/Github/EntityLib",
+    "node.js.detected.package.eslint": "true",
+    "node.js.detected.package.tslint": "true",
+    "node.js.selected.package.eslint": "(autodetect)",
+    "node.js.selected.package.tslint": "(autodetect)",
+    "nodejs_package_manager_path": "npm",
+    "project.structure.last.edited": "Modules",
+    "project.structure.proportion": "0.15",
+    "project.structure.side.proportion": "0.2",
+    "settings.editor.selected.configurable": "preferences.editor",
+    "vue.rearranger.settings.migration": "true"
   },
-  &quot;keyToStringList&quot;: {
-    &quot;kotlin-gradle-user-dirs&quot;: [
-      &quot;/home/tofaa/.gradle&quot;
+  "keyToStringList": {
+    "kotlin-gradle-user-dirs": [
+      "/home/tofaa/.gradle"
     ]
   }
-}</component>
+}]]></component>
   <component name="RecentsManager">
     <key name="CopyFile.RECENT_KEYS">
       <recent name="$PROJECT_DIR$/model-engine-addon" />
@@ -313,8 +290,8 @@
   <component name="SharedIndexes">
     <attachedChunks>
       <set>
-        <option value="bundled-jdk-9f38398b9061-18abd8497189-intellij.indexing.shared.core-IU-241.14494.240" />
-        <option value="bundled-js-predefined-1d06a55b98c1-74d2a5396914-JavaScript-IU-241.14494.240" />
+        <option value="bundled-jdk-9f38398b9061-39b83d9b5494-intellij.indexing.shared.core-IU-241.15989.150" />
+        <option value="bundled-js-predefined-1d06a55b98c1-91d5c284f522-JavaScript-IU-241.15989.150" />
       </set>
     </attachedChunks>
   </component>
@@ -408,6 +385,7 @@
       <workItem from="1716488324710" duration="3710000" />
       <workItem from="1716722129881" duration="965000" />
       <workItem from="1716926795264" duration="1000" />
+      <workItem from="1718023888535" duration="1738000" />
     </task>
     <servers />
   </component>
@@ -428,7 +406,7 @@
         </line-breakpoint>
         <line-breakpoint enabled="true" type="java-line">
           <url>file://$PROJECT_DIR$/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java</url>
-          <line>33</line>
+          <line>42</line>
           <option name="timeStamp" value="3" />
         </line-breakpoint>
         <line-breakpoint enabled="true" type="java-line">
diff --git a/api/src/main/java/me/tofaa/entitylib/utils/Check.java b/api/src/main/java/me/tofaa/entitylib/utils/Check.java
index 82816ea..478ed49 100644
--- a/api/src/main/java/me/tofaa/entitylib/utils/Check.java
+++ b/api/src/main/java/me/tofaa/entitylib/utils/Check.java
@@ -5,6 +5,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.text.MessageFormat;
+import java.util.List;
 import java.util.Objects;
 
 /**
@@ -14,6 +15,18 @@ public final class Check {
 
     private Check() {}
 
+
+    public static <T> void arrayLength(List<T> lines, int index, T e) {
+        if (index >= lines.size()) {
+            for (int i = lines.size(); i < index; i++) {
+                lines.add(null);
+            }
+            lines.add(e);
+        }
+        else {lines.set(index, e);
+        }
+    }
+
     @Contract("null, _ -> fail")
     public static void notNull(@Nullable Object object, @NotNull String reason) {
         if (Objects.isNull(object)) {
diff --git a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java
index 88ab529..2327d08 100644
--- a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java
+++ b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/Hologram.java
@@ -1,5 +1,6 @@
 package me.tofaa.entitylib.wrapper.hologram;
 
+import com.github.retrooper.packetevents.protocol.player.User;
 import com.github.retrooper.packetevents.protocol.world.Location;
 import me.tofaa.entitylib.meta.display.TextDisplayMeta;
 import net.kyori.adventure.text.Component;
@@ -7,24 +8,26 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
+import java.util.UUID;
 import java.util.function.Consumer;
 
-public interface Hologram<W> {
+public interface Hologram {
 
-    static <C> Hologram.@NotNull Legacy<C> legacy(@NotNull Location location) {
-        return new LegacyHologram<>(location);
+    static  Hologram.@NotNull Legacy legacy(@NotNull Location location) {
+        return new LegacyHologram(location);
     }
 
-    static <C> Hologram.@NotNull Legacy<C> legacy(@NotNull Location location, List<Component> lines) {
-        return new LegacyHologram<>(location, lines);
+    static  Hologram.@NotNull Legacy legacy(@NotNull Location location, List<Component> lines) {
+        return new LegacyHologram(location, lines);
     }
 
-    static <C> Hologram.@NotNull Modern<C> modern(@NotNull Location location) {
-        return new ModernHologram<>(location);
+
+    static  Hologram.@NotNull Modern modern(@NotNull Location location) {
+        return new ModernHologram(location);
     }
 
-    static <C> Hologram.@NotNull Modern<C> modern(@NotNull Location location, List<Component> lines) {
-        return new ModernHologram<>(location, lines);
+    static  Hologram.@NotNull Modern modern(@NotNull Location location, List<Component> lines) {
+        return new ModernHologram(location, lines);
     }
 
     @NotNull Location getLocation();
@@ -44,13 +47,18 @@ public interface Hologram<W> {
 
     void addLine(@Nullable Component line);
 
-    interface Modern<W> extends Hologram<W> {
+    void addViewer(@NotNull UUID viewer);
+    default void addViewer(@NotNull User user) {
+        addViewer(user.getUUID());
+    }
+
+    interface Modern extends Hologram {
 
         // I got too lazy
         void setModifier(@NotNull Consumer<TextDisplayMeta> consumer);
 
     }
-    interface Legacy<W> extends Hologram<W> {
+    interface Legacy extends Hologram {
 
         float getLineOffset(boolean marker);
 
diff --git a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java
index c501a3d..4062f21 100644
--- a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java
+++ b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/LegacyHologram.java
@@ -4,6 +4,7 @@ import com.github.retrooper.packetevents.protocol.entity.type.EntityTypes;
 import com.github.retrooper.packetevents.protocol.world.Location;
 import me.tofaa.entitylib.EntityLib;
 import me.tofaa.entitylib.meta.other.ArmorStandMeta;
+import me.tofaa.entitylib.utils.Check;
 import me.tofaa.entitylib.wrapper.WrapperEntity;
 import net.kyori.adventure.text.Component;
 import org.jetbrains.annotations.NotNull;
@@ -11,11 +12,12 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.UUID;
 
-final class LegacyHologram<W> implements Hologram.Legacy<W> {
+final class LegacyHologram implements Hologram.Legacy {
 
     private Location location;
-    private List<WrapperEntity> lines = new ArrayList<>(3);
+    private final List<WrapperEntity> lines = new ArrayList<>(3);
     private float lineOffset = -0.9875f;
     private float markerOffset = -0.40625f;
     private boolean marker;
@@ -31,6 +33,13 @@ final class LegacyHologram<W> implements Hologram.Legacy<W> {
         }
     }
 
+    @Override
+    public void addViewer(@NotNull UUID viewer) {
+        for (WrapperEntity line : lines) {
+            line.addViewer(viewer);
+        }
+    }
+
     @Override
     public boolean isMarker() {
         return marker;
@@ -95,7 +104,7 @@ final class LegacyHologram<W> implements Hologram.Legacy<W> {
         meta.setHasNoGravity(true);
         meta.setSmall(true);
         meta.setMarker(marker);
-        this.lines.set(index, e);
+        Check.arrayLength(lines, index, e);
         e.spawn(location);
         teleport(location);
     }
diff --git a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java
index c8ebb75..110af16 100644
--- a/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java
+++ b/api/src/main/java/me/tofaa/entitylib/wrapper/hologram/ModernHologram.java
@@ -4,6 +4,7 @@ import com.github.retrooper.packetevents.protocol.entity.type.EntityTypes;
 import com.github.retrooper.packetevents.protocol.world.Location;
 import me.tofaa.entitylib.EntityLib;
 import me.tofaa.entitylib.meta.display.TextDisplayMeta;
+import me.tofaa.entitylib.utils.Check;
 import me.tofaa.entitylib.wrapper.WrapperEntity;
 import net.kyori.adventure.text.Component;
 import org.jetbrains.annotations.NotNull;
@@ -11,13 +12,15 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.UUID;
 import java.util.function.Consumer;
 
-final class ModernHologram<W> implements Hologram.Modern<W> {
+final class ModernHologram implements Hologram.Modern {
 
     private Location location;
-    private List<WrapperEntity> lines = new ArrayList<>(3);
+    private final List<WrapperEntity> lines = new ArrayList<>(3);
     private Consumer<TextDisplayMeta> modifier;
+    private boolean spawned = false;
 
     ModernHologram(@NotNull Location location) {
         this.location = location;
@@ -36,6 +39,7 @@ final class ModernHologram<W> implements Hologram.Modern<W> {
             line.spawn(location);
         }
         teleport(location);
+        spawned = true;
     }
 
     @Override
@@ -43,6 +47,7 @@ final class ModernHologram<W> implements Hologram.Modern<W> {
         for (WrapperEntity line : lines) {
             line.despawn();
         }
+        spawned = false;
     }
 
     @Override
@@ -72,10 +77,14 @@ final class ModernHologram<W> implements Hologram.Modern<W> {
         meta.setInvisible(true);
         meta.setHasNoGravity(true);
         meta.setText(line);
-        this.modifier.accept(meta);
-        this.lines.set(index, e);
-        e.spawn(location);
-        teleport(location);
+        if (this.modifier != null) {
+            this.modifier.accept(meta);
+        }
+        Check.arrayLength(lines, index, e);
+        if (spawned) {
+            e.spawn(location);
+            teleport(location);
+        }
     }
 
     @Override
@@ -83,6 +92,13 @@ final class ModernHologram<W> implements Hologram.Modern<W> {
         setLine(lines.size(), line);
     }
 
+    @Override
+    public void addViewer(@NotNull UUID viewer) {
+        for (WrapperEntity line : lines) {
+            line.addViewer(viewer);
+        }
+    }
+
 
     @Override
     public int length() {
diff --git a/test-plugin/build.gradle b/test-plugin/build.gradle
index 4d089d7..7552bc9 100644
--- a/test-plugin/build.gradle
+++ b/test-plugin/build.gradle
@@ -34,7 +34,7 @@ dependencies {
     compileOnly('org.spigotmc:spigot-api:1.20.1-R0.1-SNAPSHOT')
     compileOnly('com.github.retrooper.packetevents:spigot:2.3.0')
 //    implementation(project(":platforms:spigot"))
-    implementation("com.github.Tofaa2.EntityLib:spigot:2.2.0-SNAPSHOT")
+    implementation(project(":platforms:spigot"))
 }
 
 
diff --git a/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java b/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java
index c8baf17..415de2d 100644
--- a/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java
+++ b/test-plugin/src/main/java/me/tofaa/testentitylib/TestEntityLibPlugin.java
@@ -42,6 +42,7 @@ public class TestEntityLibPlugin extends JavaPlugin {
             commandMap = (CommandMap) Bukkit.getServer().getClass().getMethod("getCommandMap").invoke(Bukkit.getServer());
             commandMap.register("testapi", new TestTextDisplayCommand());
             commandMap.register("testplayer", new TestPlayerCommand());
+            commandMap.register("testholo", new TestHologramsCommand());
         }
         catch (NoSuchMethodException | InvocationTargetException | IllegalAccessException e) {
             e.printStackTrace();
diff --git a/test-plugin/src/main/java/me/tofaa/testentitylib/TestHologramsCommand.java b/test-plugin/src/main/java/me/tofaa/testentitylib/TestHologramsCommand.java
new file mode 100644
index 0000000..6ee8f0d
--- /dev/null
+++ b/test-plugin/src/main/java/me/tofaa/testentitylib/TestHologramsCommand.java
@@ -0,0 +1,48 @@
+package me.tofaa.testentitylib;
+
+import io.github.retrooper.packetevents.util.SpigotConversionUtil;
+import me.tofaa.entitylib.wrapper.hologram.Hologram;
+import net.kyori.adventure.text.Component;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.defaults.BukkitCommand;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class TestHologramsCommand extends BukkitCommand {
+
+
+    TestHologramsCommand () {
+        super("testholo");
+    }
+
+    @Override
+    public boolean execute(@NotNull CommandSender commandSender, @NotNull String s, @NotNull String[] strings) {
+        if (strings.length == 0) {
+            commandSender.sendMessage("Usage: /testholo <legacy|modern>");
+            return true;
+        }
+        Player player = (Player) commandSender;
+        if (strings[0].equalsIgnoreCase("modern")) {
+             Hologram.Modern holo =Hologram.modern(SpigotConversionUtil.fromBukkitLocation(player.getLocation()));
+            holo.addLine(Component.text("Hello, World!"));
+            holo.show();
+            holo.addViewer(player.getUniqueId());
+        }
+        if (strings[0].equalsIgnoreCase("legacy")) {
+            Hologram.Legacy holo = Hologram.legacy(SpigotConversionUtil.fromBukkitLocation(player.getLocation()));
+            holo.addLine(Component.text("Hello, World!"));
+            holo.show();
+            holo.addViewer(player.getUniqueId());
+        }
+        return true;
+    }
+
+    @NotNull
+    @Override
+    public List<String> tabComplete(@NotNull CommandSender sender, @NotNull String alias, @NotNull String[] args) throws IllegalArgumentException {
+        return Arrays.asList("legacy", "modern");
+    }
+}