Adds tab completion to the encrypt and group encrypt commands

src/main/java/net/knarcraft/bookswithoutborders/command/CommandEncrypt.java

@@ -5,16 +5,19 @@ import net.knarcraft.bookswithoutborders.state.EncryptionStyle;
 import net.knarcraft.bookswithoutborders.utility.EncryptionHelper;
 import net.knarcraft.bookswithoutborders.utility.InventoryHelper;
 import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabExecutor;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.BookMeta;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Command executor for the encrypt command
  */
-public class CommandEncrypt implements CommandExecutor {
+public class CommandEncrypt implements TabExecutor {
 
     @Override
     public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
@@ -90,4 +93,40 @@ public class CommandEncrypt implements CommandExecutor {
         }
     }
 
+    @Override
+    public List<String> onTabComplete(CommandSender sender, Command command, String alias, String[] args) {
+        return doTabCompletion(args, false);
+    }
+
+    /**
+     * Gets a list of string for tab completions
+     * @param args <p>The arguments given</p>
+     * @param groupEncrypt <p>Whether to auto-complete for group encryption</p>
+     * @return <p>The strings to auto-complete</p>
+     */
+    protected List<String> doTabCompletion(String[] args, boolean groupEncrypt) {
+        int argumentsCount = args.length;
+
+        List<String> encryptionStyles = new ArrayList<>();
+        encryptionStyles.add("dna");
+        encryptionStyles.add("substitution");
+
+        if (argumentsCount == 1) {
+            List<String> info = new ArrayList<>();
+            info.add("<password>");
+            return info;
+        } else if (argumentsCount == 2) {
+            if (groupEncrypt) {
+                List<String> info = new ArrayList<>();
+                info.add("<group>");
+                return info;
+            } else {
+                return encryptionStyles;
+            }
+        } else if (argumentsCount == 3 && groupEncrypt) {
+            return encryptionStyles;
+        }
+        return new ArrayList<>();
+    }
+
 }

src/main/java/net/knarcraft/bookswithoutborders/command/CommandGroupEncrypt.java

@@ -3,8 +3,8 @@ package net.knarcraft.bookswithoutborders.command;
 import net.knarcraft.bookswithoutborders.BooksWithoutBorders;
 import net.knarcraft.bookswithoutborders.state.EncryptionStyle;
 import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabExecutor;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.meta.BookMeta;
 
@@ -13,7 +13,7 @@ import java.util.List;
 /**
  * Command executor for the group encrypt command
  */
-public class CommandGroupEncrypt extends CommandEncrypt implements CommandExecutor {
+public class CommandGroupEncrypt extends CommandEncrypt implements TabExecutor {
 
     @Override
     public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
@@ -35,4 +35,9 @@ public class CommandGroupEncrypt extends CommandEncrypt implements CommandExecut
         return encryptBook(encryptionStyle, (Player) sender, args[1], args[0]);
     }
 
+    @Override
+    public List<String> onTabComplete(CommandSender sender, Command command, String alias, String[] args) {
+        return doTabCompletion(args, true);
+    }
+
 }