#1034 Create debug command structure + utility to see permission groups

- Relevant to current work... :)

src/main/java/fr/xephi/authme/command/executable/authme/debug/DebugCommand.java

@@ -0,0 +1,46 @@
+package fr.xephi.authme.command.executable.authme.debug;
+
+import fr.xephi.authme.command.ExecutableCommand;
+import org.bukkit.command.CommandSender;
+
+import javax.annotation.PostConstruct;
+import javax.inject.Inject;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+/**
+ * Debug command main.
+ */
+public class DebugCommand implements ExecutableCommand {
+
+    @Inject
+    private PermissionGroups permissionGroups;
+
+    private Map<String, DebugSection> sections;
+
+    @PostConstruct
+    private void collectSections() {
+        Map<String, DebugSection> sections = Stream.of(permissionGroups)
+            .collect(Collectors.toMap(DebugSection::getName, Function.identity()));
+        this.sections = sections;
+    }
+
+    @Override
+    public void executeCommand(CommandSender sender, List<String> arguments) {
+        if (arguments.isEmpty()) {
+            sender.sendMessage("Available sections:");
+            sections.values()
+                .forEach(e -> sender.sendMessage("- " + e.getName() + ": " + e.getDescription()));
+        } else {
+            DebugSection debugSection = sections.get(arguments.get(0).toLowerCase());
+            if (debugSection == null) {
+                sender.sendMessage("Unknown subcommand");
+            } else {
+                debugSection.execute(sender, arguments.subList(1, arguments.size()));
+            }
+        }
+    }
+}

src/main/java/fr/xephi/authme/command/executable/authme/debug/DebugSection.java

@@ -0,0 +1,30 @@
+package fr.xephi.authme.command.executable.authme.debug;
+
+import org.bukkit.command.CommandSender;
+
+import java.util.List;
+
+/**
+ * A debug section: "child" command of the debug command.
+ */
+interface DebugSection {
+
+    /**
+     * @return the name to get to this child command
+     */
+    String getName();
+
+    /**
+     * @return short description of the child command
+     */
+    String getDescription();
+
+    /**
+     * Executes the debug child command.
+     *
+     * @param sender the sender executing the command
+     * @param arguments the arguments, without the label of the child command
+     */
+    void execute(CommandSender sender, List<String> arguments);
+
+}

src/main/java/fr/xephi/authme/command/executable/authme/debug/PermissionGroups.java

@@ -0,0 +1,40 @@
+package fr.xephi.authme.command.executable.authme.debug;
+
+import fr.xephi.authme.permission.PermissionsManager;
+import org.bukkit.Bukkit;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+
+import javax.inject.Inject;
+import java.util.List;
+
+/**
+ * Outputs the permission groups of a player.
+ */
+class PermissionGroups implements DebugSection {
+
+    @Inject
+    private PermissionsManager permissionsManager;
+
+    @Override
+    public String getName() {
+        return "groups";
+    }
+
+    @Override
+    public String getDescription() {
+        return "Show permission groups a player belongs to";
+    }
+
+    @Override
+    public void execute(CommandSender sender, List<String> arguments) {
+        String name = arguments.isEmpty() ? sender.getName() : arguments.get(0);
+        Player player = Bukkit.getPlayer(name);
+        if (player == null) {
+            sender.sendMessage("Player " + name + " could not be found");
+        } else {
+            sender.sendMessage("Player " + name + " has permission groups: "
+                + String.join(", ", permissionsManager.getGroups(player)));
+        }
+    }
+}