From cc1a54b5f02cb1d02ee7a558686f83a4076cccd6 Mon Sep 17 00:00:00 2001
From: Matthew Miller <mnmiller1@me.com>
Date: Sun, 23 Sep 2018 22:48:04 +1000
Subject: [PATCH] Added an implementation tester to Bukkit, to determine which
 impl is in use. (For WE,WG,CB to use Paper/Spigot specific APIs)

---
 .../bukkit/BukkitImplementationTester.java    | 90 +++++++++++++++++++
 .../worldedit/bukkit/WorldEditPlugin.java     |  3 +
 2 files changed, 93 insertions(+)
 create mode 100644 worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitImplementationTester.java

diff --git a/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitImplementationTester.java b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitImplementationTester.java
new file mode 100644
index 000000000..186365a9b
--- /dev/null
+++ b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitImplementationTester.java
@@ -0,0 +1,90 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.sk89q.worldedit.bukkit;
+
+/**
+ * Adds methods to test if different API methods are possible based on implementation.
+ */
+public class BukkitImplementationTester {
+
+    private BukkitImplementationTester() {
+    }
+
+    /**
+     * Known Bukkit implementations
+     */
+    public enum BukkitImplementation {
+        CRAFTBUKKIT,
+        SPIGOT,
+        PAPER,
+    }
+
+    private static final String implementationMessage = "************************************************" +
+                                                        "* Note: PaperMC (https://papermc.io/) is       *" +
+                                                        "* recommended for optimal performance with     *" +
+                                                        "* WorldEdit, WorldGuard, or CraftBook.         *" +
+                                                        "************************************************";
+
+    private static BukkitImplementation implementation;
+
+    /**
+     * Gets the implementation currently in use on the server.
+     *
+     * @return The server implementation
+     */
+    public static BukkitImplementation getImplementation() {
+        if (implementation == null) {
+            try {
+                Class.forName("com.destroystokyo.paper.PaperConfig");
+                implementation = BukkitImplementation.PAPER;
+            } catch (Exception e) {
+                try {
+                    Class.forName("org.spigotmc.SpigotConfig");
+                    implementation = BukkitImplementation.SPIGOT;
+                } catch (Exception e2) {
+                    implementation = BukkitImplementation.CRAFTBUKKIT;
+                }
+            }
+
+            if (implementation != BukkitImplementation.PAPER) {
+//                 Bukkit.getServer().getConsoleSender().sendMessage(implementationMessage); // TODO Decide if good idea.
+            }
+        }
+
+        return implementation;
+    }
+
+    /**
+     * Check if this implementation is compatible with Spigot APIs
+     *
+     * @return If compatible with Spigot APIs
+     */
+    public static boolean isSpigotCompatible() {
+        return getImplementation() == BukkitImplementation.SPIGOT || getImplementation() == BukkitImplementation.PAPER;
+    }
+
+    /**
+     * Check if this implementation is compatible with Paper APIs
+     *
+     * @return If compatible with Paper APIs
+     */
+    public static boolean isPaperCompatible() {
+        return getImplementation() == BukkitImplementation.PAPER;
+    }
+}
diff --git a/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java
index c4b017e83..8cc6f544b 100644
--- a/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java
+++ b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java
@@ -104,6 +104,9 @@ public class WorldEditPlugin extends JavaPlugin implements TabCompleter {
         // platforms to be worried about... at the current time of writing
         WorldEdit.getInstance().getEventBus().post(new PlatformReadyEvent());
 
+        // Setup the BukkitImplementationTester.
+        BukkitImplementationTester.getImplementation();
+
         // Enable metrics
         new Metrics(this);
     }