Show a message with install instructions when running the jar file

Co-Authored-By: Matthew Miller <mnmiller1@me.com>

worldedit-core/src/main/java/com/sk89q/worldedit/WorldEditManifest.java

@@ -34,11 +34,32 @@ import javax.annotation.Nullable;
 public class WorldEditManifest {
 
     public static final String WORLD_EDIT_VERSION = "WorldEdit-Version";
+    public static final String WORLD_EDIT_KIND = "WorldEdit-Kind";
+
+    public enum Kind {
+        MOD("mods"),
+        PLUGIN("plugins"),
+        UNKNOWN("mods/plugins"),
+        ;
+
+        public final String folderName;
+
+        Kind(String folderName) {
+            this.folderName = folderName;
+        }
+    }
 
     public static WorldEditManifest load() {
         Attributes attributes = readAttributes();
+        Kind kind;
+        try {
+            kind = Kind.valueOf(readAttribute(attributes, WORLD_EDIT_KIND, () -> "UNKNOWN"));
+        } catch (IllegalArgumentException e) {
+            kind = Kind.UNKNOWN;
+        }
         return new WorldEditManifest(
-            readAttribute(attributes, WORLD_EDIT_VERSION, () -> "(unknown)")
+            readAttribute(attributes, WORLD_EDIT_VERSION, () -> "(unknown)"),
+                kind
         );
     }
 
@@ -71,12 +92,18 @@ public class WorldEditManifest {
     }
 
     private final String worldEditVersion;
+    private final Kind worldEditKind;
 
-    private WorldEditManifest(String worldEditVersion) {
+    private WorldEditManifest(String worldEditVersion, Kind worldEditKind) {
         this.worldEditVersion = worldEditVersion;
+        this.worldEditKind = worldEditKind;
     }
 
     public String getWorldEditVersion() {
         return worldEditVersion;
     }
+
+    public Kind getWorldEditKind() {
+        return worldEditKind;
+    }
 }

worldedit-core/src/main/java/com/sk89q/worldedit/internal/util/InfoEntryPoint.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 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.internal.util;
+
+import com.sk89q.worldedit.WorldEditManifest;
+
+import java.awt.Desktop;
+import java.io.IOException;
+import java.net.URISyntaxException;
+import javax.swing.JOptionPane;
+import javax.swing.JTextPane;
+import javax.swing.UIManager;
+import javax.swing.event.HyperlinkEvent;
+import javax.swing.text.html.HTMLDocument;
+import javax.swing.text.html.HTMLEditorKit;
+
+public class InfoEntryPoint {
+
+    private static final String INSTALL_URL = "https://wiki.intellectualsites.com/FastAsyncWorldEdit";
+    private static final String SUPPORT_URL = "https://discord.gg/intellectualsites";
+
+    private static String getMessage(boolean html) {
+        WorldEditManifest manifest = WorldEditManifest.load();
+
+        return "To install FastAsyncWorldEdit, place it in the "
+                + manifest.getWorldEditKind().folderName + " folder.\n"
+                + "For more detailed instructions, see " + formatLink(INSTALL_URL, html) + "\n"
+                + "For further help, check out our support Discord at "
+                + formatLink(SUPPORT_URL, html) + "\n"
+                + "\n"
+                + "Version: " + manifest.getWorldEditVersion() + "\n";
+    }
+
+    private static String formatLink(String url, boolean html) {
+        return html ? String.format("<a href=\"%1$s\">%1$s</a>", url) : url;
+    }
+
+    public static void main(String[] args) {
+        if (System.console() != null) {
+            System.err.println(getMessage(false));
+        } else {
+            System.setProperty("awt.useSystemAAFontSettings", "lcd");
+            JOptionPane.showMessageDialog(
+                    null,
+                    new NavigableEditorPane(getMessage(true)),
+                    "FastAsyncWorldEdit",
+                    JOptionPane.INFORMATION_MESSAGE
+            );
+        }
+        System.exit(1);
+    }
+
+    private static class NavigableEditorPane extends JTextPane {
+        public NavigableEditorPane(String htmlBody) {
+            super(new HTMLDocument());
+            setEditorKit(new HTMLEditorKit());
+            setText(htmlBody.replace("\n", "<br>"));
+            setBackground(UIManager.getColor("Panel.background"));
+
+            addHyperlinkListener(e -> {
+                if (e.getEventType().equals(HyperlinkEvent.EventType.ACTIVATED)) {
+                    try {
+                        Desktop.getDesktop().browse(e.getURL().toURI());
+                    } catch (IOException | URISyntaxException ex) {
+                        ex.printStackTrace();
+                    }
+                }
+            });
+            setEditable(false);
+            setBorder(null);
+        }
+    }
+}