Cleanup MessageUtilities (#190)

Removes the exception and functional interface, since their use is
entirely avoidable and replaceable with normal Java conventions of
return values and Optional.

Uses JDA's message jump URL pattern for robustness, instead of matching
only normal (non-canary/PTB) Discord links and using manual string
manipulation to obtain the IDs.

Author: sciwhiz12

src/commander/java/com/mcmoddev/mmdbot/commander/TheCommander.java

@@ -546,17 +546,15 @@ public Jdbi getJdbi() {
     }
 
     @Nullable
-    public RestAction<Message> getMessageByLink(final String link) throws MessageUtilities.MessageLinkException {
-        final AtomicReference<RestAction<Message>> returnAtomic = new AtomicReference<>();
-        MessageUtilities.decodeMessageLink(link, (guildId, channelId, messageId) -> {
-            final var guild = getJda().getGuildById(guildId);
-            if (guild == null) return;
-            final var channel = guild.getChannelById(MessageChannel.class, channelId);
-            if (channel != null) {
-                returnAtomic.set(channel.retrieveMessageById(messageId));
-            }
-        });
-        return returnAtomic.get();
+    public RestAction<Message> getMessageByLink(final String link) {
+        return MessageUtilities.decodeMessageLink(link)
+            .map(info -> {
+                final var guild = getJda().getGuildById(info.guildId());
+                if (guild == null) return null;
+                final var channel = guild.getChannelById(MessageChannel.class, info.channelId());
+                return channel == null ? null : channel.retrieveMessageById(info.messageId());
+            })
+            .orElse(null);
     }
 
     public String getGithubToken() {

src/commander/java/com/mcmoddev/mmdbot/commander/eventlistener/ReferencingListener.java

@@ -56,21 +56,14 @@ public void onMessageReceived(@NonNull MessageReceivedEvent event) {
             return;
         }
 
-        final var matcher = MessageUtilities.MESSAGE_LINK_PATTERN.matcher(msg[0]);
-        if (matcher.find()) {
-            try {
-                final var m = TheCommander.getInstance().getMessageByLink(msg[0]);
-                if (m != null) {
-                    m.queue(message -> {
-                        event.getChannel().sendMessageEmbeds(reference(message, event.getMember())).queue();
-                        if (msg.length == 1) {
-                            originalMsg.delete().reason("Quote successful").queue();
-                        }
-                    });
+        final var m = TheCommander.getInstance().getMessageByLink(msg[0]);
+        if (m != null) {
+            m.queue(message -> {
+                event.getChannel().sendMessageEmbeds(reference(message, event.getMember())).queue();
+                if (msg.length == 1) {
+                    originalMsg.delete().reason("Quote successful").queue();
                 }
-            } catch (MessageUtilities.MessageLinkException e) {
-                // Do nothing
-            }
+            });
         }
     }
 

src/core/java/com/mcmoddev/mmdbot/core/util/MessageUtilities.java

@@ -20,20 +20,22 @@
  */
 package com.mcmoddev.mmdbot.core.util;
 
+import com.jagrosh.jdautilities.commons.utils.SafeIdUtil;
 import lombok.NonNull;
 import lombok.experimental.UtilityClass;
 import net.dv8tion.jda.api.entities.Message;
 import net.dv8tion.jda.api.interactions.components.ActionRow;
 import net.dv8tion.jda.api.interactions.components.buttons.Button;
 
-import java.io.Serial;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.regex.Pattern;
 
 @UtilityClass
 public class MessageUtilities {
 
+    // TODO: expand this, see JDA's Message.JUMP_URL_PATTERN
     public static final Pattern MESSAGE_LINK_PATTERN = Pattern.compile("https://discord.com/channels/");
 
     /**
@@ -59,56 +61,21 @@ public static void disableButtons(@NonNull Message message) {
             .queue();
     }
 
-    public static void decodeMessageLink(final String link, MessageInfo consumer)
-        throws MessageLinkException {
-        final var matcher = MESSAGE_LINK_PATTERN.matcher(link);
-        if (matcher.find()) {
-            try {
-                var originalWithoutLink = matcher.replaceAll("");
-                if (originalWithoutLink.indexOf('/') > -1) {
-                    final long guildId = Long
-                        .parseLong(originalWithoutLink.substring(0, originalWithoutLink.indexOf('/')));
-                    originalWithoutLink = originalWithoutLink.substring(originalWithoutLink.indexOf('/') + 1);
-                    if (originalWithoutLink.indexOf('/') > -1) {
-                        final long channelId = Long
-                            .parseLong(originalWithoutLink.substring(0, originalWithoutLink.indexOf('/')));
-                        originalWithoutLink = originalWithoutLink.substring(originalWithoutLink.indexOf('/') + 1);
-                        final long messageId = Long.parseLong(originalWithoutLink);
-                        consumer.accept(guildId, channelId, messageId);
-                    } else {
-                        throw new MessageLinkException("Invalid Link");
-                    }
-                } else {
-                    throw new MessageLinkException("Invalid Link");
-                }
-            } catch (NumberFormatException e) {
-                throw new MessageLinkException(e);
-            }
-        } else {
-            throw new MessageLinkException("Invalid Link");
-        }
-    }
-
-    public static class MessageLinkException extends Exception {
+    public static Optional<MessageLinkInformation> decodeMessageLink(final String link) {
+        final var matcher = Message.JUMP_URL_PATTERN.matcher(link);
+        if (!matcher.find()) return Optional.empty();
 
-        @Serial
-        private static final long serialVersionUID = -2805786147679905681L;
-
-        public MessageLinkException(Throwable e) {
-            super(e);
-        }
+        try {
+            final long guildId = SafeIdUtil.safeConvert(matcher.group("guild"));
+            final long channelId = SafeIdUtil.safeConvert(matcher.group("channel"));
+            final long messageId = SafeIdUtil.safeConvert(matcher.group("message"));
 
-        public MessageLinkException(String message) {
-            super(message);
+            return Optional.of(new MessageLinkInformation(guildId, channelId, messageId));
+        } catch (NumberFormatException e) {
+            return Optional.empty();
         }
-
     }
 
-    @FunctionalInterface
-    public interface MessageInfo {
-
-        void accept(final long guildId, final long channelId, final long messageId);
-
+    public record MessageLinkInformation(long guildId, long channelId, long messageId) {
     }
-
 }