Add kick command and helpful messages

src/main/java/sciwhiz12/janitor/commands/CommandRegistry.java

@@ -13,6 +13,7 @@ import sciwhiz12.janitor.commands.bot.ShutdownCommand;
 import sciwhiz12.janitor.commands.misc.HelloCommand;
 import sciwhiz12.janitor.commands.misc.OKCommand;
 import sciwhiz12.janitor.commands.misc.PingCommand;
+import sciwhiz12.janitor.commands.moderation.KickCommand;
 import sciwhiz12.janitor.utils.Util;
 
 import java.util.HashMap;
@@ -36,6 +37,7 @@ public class CommandRegistry implements EventListener {
         addCommand(new PingCommand(this, "pong", "Ping!"));
         addCommand(new OKCommand(this));
         addCommand(new HelloCommand(this));
+        addCommand(new KickCommand(this));
         if (bot.getConfig().getOwnerID().isPresent()) {
             addCommand(new ShutdownCommand(this, bot.getConfig().getOwnerID().get()));
         }

src/main/java/sciwhiz12/janitor/commands/arguments/GuildMemberArgument.java

@@ -14,6 +14,7 @@ import sciwhiz12.janitor.utils.StringReaderUtil;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
@@ -102,8 +103,9 @@ public class GuildMemberArgument implements ArgumentType<GuildMemberArgument.IMe
 
         @Override
         public List<Member> fromGuild(Guild guild) throws CommandSyntaxException {
+            final String nameLowercase = name.toLowerCase(Locale.ROOT);
             final List<Member> members = guild.getMembers().stream()
-                .filter(member -> (member.getUser().getName() + '#' + member.getUser().getDiscriminator()).replaceAll("\\s", "").startsWith(name))
+                .filter(member -> (member.getUser().getName() + '#' + member.getUser().getDiscriminator()).replaceAll("\\s", "").toLowerCase(Locale.ROOT).startsWith(nameLowercase))
                 .collect(Collectors.toList());
             if (!multiple && members.size() > 1) {
                 throw MULTIPLE_MEMBERS.create();

src/main/java/sciwhiz12/janitor/commands/bot/ShutdownCommand.java

@@ -8,7 +8,7 @@ import sciwhiz12.janitor.commands.CommandRegistry;
 import sciwhiz12.janitor.utils.Util;
 
 import static sciwhiz12.janitor.Logging.JANITOR;
-import static sciwhiz12.janitor.utils.CommandHelper.literal;
+import static sciwhiz12.janitor.commands.util.CommandHelper.literal;
 
 public class ShutdownCommand extends BaseCommand {
     private final long ownerID;

src/main/java/sciwhiz12/janitor/commands/misc/HelloCommand.java

@@ -14,8 +14,8 @@ import java.util.List;
 
 import static sciwhiz12.janitor.Logging.JANITOR;
 import static sciwhiz12.janitor.commands.arguments.GuildMemberArgument.getMembers;
-import static sciwhiz12.janitor.utils.CommandHelper.argument;
-import static sciwhiz12.janitor.utils.CommandHelper.literal;
+import static sciwhiz12.janitor.commands.util.CommandHelper.argument;
+import static sciwhiz12.janitor.commands.util.CommandHelper.literal;
 
 public class HelloCommand extends BaseCommand {
     public HelloCommand(CommandRegistry registry) {

src/main/java/sciwhiz12/janitor/commands/misc/OKCommand.java

@@ -8,7 +8,7 @@ import sciwhiz12.janitor.commands.CommandRegistry;
 import sciwhiz12.janitor.utils.Util;
 
 import static sciwhiz12.janitor.Logging.JANITOR;
-import static sciwhiz12.janitor.utils.CommandHelper.literal;
+import static sciwhiz12.janitor.commands.util.CommandHelper.literal;
 
 public class OKCommand extends BaseCommand {
     public OKCommand(CommandRegistry registry) {

src/main/java/sciwhiz12/janitor/commands/misc/PingCommand.java

@@ -8,7 +8,7 @@ import sciwhiz12.janitor.commands.CommandRegistry;
 import sciwhiz12.janitor.utils.Util;
 
 import static sciwhiz12.janitor.Logging.JANITOR;
-import static sciwhiz12.janitor.utils.CommandHelper.literal;
+import static sciwhiz12.janitor.commands.util.CommandHelper.literal;
 
 public class PingCommand extends BaseCommand {
     private final String command;

src/main/java/sciwhiz12/janitor/commands/moderation/KickCommand.java

@@ -0,0 +1,69 @@
+package sciwhiz12.janitor.commands.moderation;
+
+import com.mojang.brigadier.builder.LiteralArgumentBuilder;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import sciwhiz12.janitor.commands.BaseCommand;
+import sciwhiz12.janitor.commands.CommandRegistry;
+import sciwhiz12.janitor.commands.util.CommandHelper;
+import sciwhiz12.janitor.commands.util.ModerationHelper;
+import sciwhiz12.janitor.msg.General;
+import sciwhiz12.janitor.msg.Moderation;
+
+import java.util.EnumSet;
+import java.util.List;
+
+import static com.mojang.brigadier.arguments.StringArgumentType.getString;
+import static com.mojang.brigadier.arguments.StringArgumentType.greedyString;
+import static sciwhiz12.janitor.commands.arguments.GuildMemberArgument.getMembers;
+import static sciwhiz12.janitor.commands.arguments.GuildMemberArgument.member;
+
+public class KickCommand extends BaseCommand {
+    public static final EnumSet<Permission> KICK_PERMISSION = EnumSet.of(Permission.KICK_MEMBERS);
+
+    public KickCommand(CommandRegistry registry) {
+        super(registry);
+    }
+
+    @Override
+    public LiteralArgumentBuilder<MessageReceivedEvent> getNode() {
+        return CommandHelper.literal("kick")
+            .then(
+                CommandHelper.argument("member", member())
+                    .then(
+                        CommandHelper.argument("reason", greedyString())
+                            .executes(ctx -> this.runWithReason(ctx, getString(ctx, "reason")))
+                    )
+                    .executes(this::run)
+            );
+    }
+
+    private int run(CommandContext<MessageReceivedEvent> ctx) throws CommandSyntaxException {
+        return runWithReason(ctx, null);
+    }
+
+    private int runWithReason(CommandContext<MessageReceivedEvent> ctx, @Nullable String reason) throws CommandSyntaxException {
+        if (!ctx.getSource().isFromGuild()) {
+            General.guildOnlyCommand(ctx.getSource().getTextChannel()).queue();
+            return 1;
+        }
+        Member performer = ctx.getSource().getMember();
+        if (performer == null) return 1;
+        List<Member> members = getMembers("member", ctx).fromGuild(ctx.getSource().getGuild());
+        if (members.size() > 1) {
+            General.ambiguousMember(ctx.getSource().getTextChannel()).queue();
+            return 1;
+        }
+        Member target = members.get(0);
+        if (ModerationHelper.ensurePermissions(ctx.getSource().getTextChannel(), performer, target, KICK_PERMISSION)) {
+            ModerationHelper.kickUser(target.getGuild(), performer, target, reason)
+                .flatMap(v -> Moderation.kickUser(ctx.getSource().getChannel(), performer, target, reason))
+                .queue();
+        }
+        return 1;
+    }
+}

src/main/java/sciwhiz12/janitor/commands/util/CommandHelper.java

@@ -0,0 +1,39 @@
+package sciwhiz12.janitor.commands.util;
+
+import com.mojang.brigadier.arguments.ArgumentType;
+import com.mojang.brigadier.builder.LiteralArgumentBuilder;
+import com.mojang.brigadier.builder.RequiredArgumentBuilder;
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.Guild;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.entities.TextChannel;
+import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import sciwhiz12.janitor.msg.General;
+
+import java.util.EnumSet;
+
+public class CommandHelper {
+    public static LiteralArgumentBuilder<MessageReceivedEvent> literal(String command) {
+        return LiteralArgumentBuilder.literal(command);
+    }
+
+    public static <Arg> RequiredArgumentBuilder<MessageReceivedEvent, Arg> argument(String command, ArgumentType<Arg> argument) {
+        return RequiredArgumentBuilder.argument(command, argument);
+    }
+
+    public static boolean canInteract(TextChannel response, Member target) {
+        if (!target.getGuild().getSelfMember().canInteract(target)) {
+            General.cannotInteract(response, target).queue();
+            return false;
+        }
+        return true;
+    }
+
+    public static boolean hasPermission(TextChannel response, Guild guild, EnumSet<Permission> permissions) {
+        if (!guild.getSelfMember().hasPermission(permissions)) {
+            General.insufficientPermissions(response, permissions).queue();
+            return false;
+        }
+        return true;
+    }
+}

src/main/java/sciwhiz12/janitor/commands/util/ModerationHelper.java

@@ -0,0 +1,36 @@
+package sciwhiz12.janitor.commands.util;
+
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.Guild;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.entities.TextChannel;
+import net.dv8tion.jda.api.requests.restaction.AuditableRestAction;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import sciwhiz12.janitor.msg.General;
+import sciwhiz12.janitor.msg.Moderation;
+
+import java.util.EnumSet;
+
+public class ModerationHelper {
+    public static AuditableRestAction<Void> kickUser(Guild guild, Member performer, Member target, @Nullable String reason) {
+        StringBuilder auditReason = new StringBuilder();
+        auditReason.append("Kicked by ").append(General.nameFor(performer.getUser()));
+        if (reason != null)
+            auditReason.append(" for reason: ").append(reason);
+        return guild.kick(target, auditReason.toString());
+    }
+
+    public static boolean ensurePermissions(TextChannel channel, Member performer, Member target, EnumSet<Permission> permissions) {
+        if (!CommandHelper.hasPermission(channel, target.getGuild(), permissions)) return false;
+        if (!CommandHelper.canInteract(channel, target)) return false;
+        if (!performer.hasPermission(permissions)) {
+            Moderation.performerInsufficientPermissions(channel, performer, permissions).queue();
+            return false;
+        }
+        if (!performer.canInteract(target)) {
+            Moderation.cannotModerate(channel, performer, target).queue();
+            return false;
+        }
+        return true;
+    }
+}

src/main/java/sciwhiz12/janitor/msg/General.java

@@ -0,0 +1,67 @@
+package sciwhiz12.janitor.msg;
+
+import net.dv8tion.jda.api.EmbedBuilder;
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.*;
+import net.dv8tion.jda.api.requests.RestAction;
+
+import java.util.EnumSet;
+import java.util.stream.Collectors;
+
+public final class General {
+    public static final int FAILURE_COLOR = 0xF73132;
+
+    private General() {
+    }
+
+    public static RestAction<Message> guildOnlyCommand(TextChannel channel) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("Guild only command!")
+                .setDescription("The previous command can only be run in a guild channel.")
+                .setColor(FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static RestAction<Message> insufficientPermissions(TextChannel channel, EnumSet<Permission> permissions) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("I have insufficient permissions!")
+                .setDescription("I do not have sufficient permissions to carry out this action!\n" +
+                    "Please contact your server admins if you believe this is in error.")
+                .addField(new MessageEmbed.Field(
+                    "Required permissions",
+                    permissions.stream().map(Permission::getName).collect(Collectors.joining(", ")),
+                    false))
+                .setColor(FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static RestAction<Message> ambiguousMember(TextChannel channel) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("Ambiguous member argument!")
+                .setDescription("The name you have specified is too ambiguous (leads to more than 1 member)!\n" +
+                    "Please narrow down the specified name until it can uniquely identify a member of this guild.")
+                .setColor(FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static RestAction<Message> cannotInteract(TextChannel channel, Member target) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("Member is higher than me!")
+                .setDescription("Cannot perform action on the given member, as they higher up in the hierarchy than me.")
+                .addField("Target", nameFor(target.getUser()), true)
+                .setColor(General.FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static String nameFor(User user) {
+        return user.getName().concat("#").concat(user.getDiscriminator());
+    }
+}

src/main/java/sciwhiz12/janitor/msg/Moderation.java

@@ -0,0 +1,61 @@
+package sciwhiz12.janitor.msg;
+
+import net.dv8tion.jda.api.EmbedBuilder;
+import net.dv8tion.jda.api.Permission;
+import net.dv8tion.jda.api.entities.Member;
+import net.dv8tion.jda.api.entities.MessageChannel;
+import net.dv8tion.jda.api.entities.MessageEmbed;
+import net.dv8tion.jda.api.requests.restaction.MessageAction;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+import java.util.EnumSet;
+import java.util.stream.Collectors;
+
+import static sciwhiz12.janitor.msg.General.nameFor;
+
+public final class Moderation {
+    public static final int MODERATION_COLOR = 0xF1BD25;
+
+    private Moderation() {
+    }
+
+    public static MessageAction performerInsufficientPermissions(MessageChannel channel, Member performer, EnumSet<Permission> permissions) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("Insufficient permissions.")
+                .setDescription("The performer of this command has insufficient permissions to use this command.")
+                .addField("Performer", nameFor(performer.getUser()), true)
+                .addField(new MessageEmbed.Field(
+                    "Required permissions",
+                    permissions.stream().map(Permission::getName).collect(Collectors.joining(", ")),
+                    true))
+                .setColor(General.FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static MessageAction cannotModerate(MessageChannel channel, Member performer, Member target) {
+        return channel.sendMessage(
+            new EmbedBuilder()
+                .setTitle("Cannot moderate Target.")
+                .setDescription("The performer of this command cannot moderate the target user, likely due to being lower in the role hierarchy.")
+                .addField("Performer", nameFor(performer.getUser()), true)
+                .addField("Target", nameFor(target.getUser()), true)
+                .setColor(General.FAILURE_COLOR)
+                .build()
+        );
+    }
+
+    public static MessageAction kickUser(MessageChannel channel, Member performer, Member target, @Nullable String reason) {
+        final EmbedBuilder embed = new EmbedBuilder()
+            .setTitle("Kicked.")
+            .addField("Performer", nameFor(performer.getUser()), true)
+            .addField("Target", nameFor(target.getUser()), true);
+        if (reason != null)
+            embed.addField("Reason", reason, false);
+        return channel.sendMessage(
+            embed.setColor(MODERATION_COLOR)
+                .build()
+        );
+    }
+}

src/main/java/sciwhiz12/janitor/utils/CommandHelper.java

@@ -1,16 +0,0 @@
-package sciwhiz12.janitor.utils;
-
-import com.mojang.brigadier.arguments.ArgumentType;
-import com.mojang.brigadier.builder.LiteralArgumentBuilder;
-import com.mojang.brigadier.builder.RequiredArgumentBuilder;
-import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
-
-public class CommandHelper {
-    public static LiteralArgumentBuilder<MessageReceivedEvent> literal(String command) {
-        return LiteralArgumentBuilder.literal(command);
-    }
-
-    public static <Arg> RequiredArgumentBuilder<MessageReceivedEvent, Arg> argument(String command, ArgumentType<Arg> argument) {
-        return RequiredArgumentBuilder.argument(command, argument);
-    }
-}