feat: moderation tool migration into webdev-bot

.env.example

@@ -10,6 +10,7 @@ GUIDES_CHANNEL_ID=your_guides_channel_id_here
 ADVENT_OF_CODE_CHANNEL_ID=your_advent_of_code_forum_channel_id_here
 REPEL_LOG_CHANNEL_ID=your_repel_log_channel_id_here
 ONBOARDING_CHANNEL_ID=onboarding_channel_id_here
+SPAM_DETECTION_CHANNEL_ID=spam_detection_channel_id_here
 ARCHIVE_CATEGORY_ID=archive_category_id_here
 
 # Role IDs (REQUIRED)

.env.production

@@ -12,6 +12,7 @@ ADVENT_OF_CODE_CHANNEL_ID=1047623689488830495
 SHOWCASE_CHANNEL_ID=1517161718818541658
 SHOWCASE_LOG_CHANNEL_ID=1517565847982444634
 SHOWCASE_RULES_CHANNEL_ID=1517948527098073158
+SPAM_DETECTION_CHANNEL_ID=973895712314110032
 ARCHIVE_CATEGORY_ID=837507969859977258
 
 

.env.test

@@ -19,6 +19,7 @@ REPEL_LOG_CHANNEL_ID=your-repel-log-channel-id
 SHOWCASE_CHANNEL_ID=your-showcase-forum-channel-id
 SHOWCASE_LOG_CHANNEL_ID=your-showcase-log-channel-id
 SHOWCASE_RULES_CHANNEL_ID=your-showcase-rules-channel-id
+SPAM_DETECTION_CHANNEL_ID=spam-detection-channel-id-here
 ARCHIVE_CATEGORY_ID=your-archived-category-id
 
 # Role IDs (from your dev server)
@@ -31,4 +32,4 @@ TAG_ACCESS_ROLE_ID=your-tag-access-role-id
 GUIDES_TRACKER_PATH=guides-tracker.json
 ADVENT_OF_CODE_TRACKER_PATH=test-advent-tracker.json
 
-DATABASE_URL=test.db
+DATABASE_URL=test.db

src/common/commands/index.ts

@@ -1,13 +1,14 @@
 import { docsCommands } from '@/features/docs/index.js';
 import { guidesCommand } from '@/features/guides/index.js';
-import cacheMessages from '@/features/moderation/cache-messages.js';
+import cacheMessages from '@/features/cache-messages/index.js';
 import { repelCommand } from '@/features/moderation/repel.js';
 import { pingCommand } from '@/features/ping/index.js';
 import { publicGuidesCommand } from '@/features/public-guides/index.js';
 import { createShowcaseCommand } from '@/features/showcase/create-showcase.js';
 import { sendShowcasePinnedMessage } from '@/features/showcase/send-pinned-message.js';
 import { tipsCommands } from '@/features/tips/index.js';
 import type { Command } from './types.js';
+import { reportMessage } from '@/features/report-message/index.js';
 import { tagCommand } from '@/features/tags/index.js';
 import { botOptionsCommand } from '@/features/bot-options/index.js';
 
@@ -22,6 +23,7 @@ export const commands = new Map<string, Command>(
     publicGuidesCommand,
     createShowcaseCommand,
     sendShowcasePinnedMessage,
+    reportMessage,
     tagCommand,
     botOptionsCommand,
   ]

src/common/events/index.ts

@@ -3,6 +3,7 @@ import { hasVarEvent } from '@/features/has-var/index.js';
 import { interactionCreateEvent } from '@/features/interaction-create/index.js';
 import { readyEvent } from '@/features/ready/index.js';
 import type { DiscordEvent } from './types.js';
+import { spamDetection } from '@/features/spam-detection/index.js';
 import archiveChannels from '@/features/archive-channels/index.js';
 import { tagReceivedEvent } from '@/features/tags/tag-received.js';
 import { reactionAddEvent } from '@/features/reactions/index.js';
@@ -13,6 +14,7 @@ export const events: DiscordEvent[] = [
   guildCreateEvent,
   hasVarEvent,
   interactionCreateEvent,
+  spamDetection,
   archiveChannels,
   tagReceivedEvent,
   reactionAddEvent,

src/env.ts

@@ -43,6 +43,7 @@ export const config = {
     showcase: requireEnv('SHOWCASE_CHANNEL_ID'),
     showcaseLogs: requireEnv('SHOWCASE_LOG_CHANNEL_ID'),
     showcaseRules: requireEnv('SHOWCASE_RULES_CHANNEL_ID'),
+    spamDetection: requireEnv('SPAM_DETECTION_CHANNEL_ID'),
     archiveCategory: requireEnv('ARCHIVE_CATEGORY_ID'),
   },
   onboarding: {

src/features/moderation/cache-messages.ts → src/features/cache-messages/index.ts

@@ -4,7 +4,7 @@ import {
   PermissionsBitField,
 } from 'discord.js';
 import { createSlashCommand } from '../../common/commands/create-commands.js';
-import { fetchAndCachePublicChannelsMessages } from '../../util/cache.js';
+import { fetchAndCachePublicChannelsMessages } from '../../util/channel-prefetch.js';
 
 export default createSlashCommand({
   data: {

src/features/has-var/index.ts

@@ -2,7 +2,7 @@ import { Events } from 'discord.js';
 import ts from 'typescript';
 import { createEvent } from '@/common/events/create-event.js';
 import { MINUTE } from '../../constants/time.js';
-import { codeBlockRegex } from '../../util/message.js';
+import { codeBlockRegex } from '@/util/text.js';
 import { rateLimit } from '../../util/rate-limit.js';
 
 const { canRun, reset } = rateLimit(5 * MINUTE);

src/features/ready/index.ts

@@ -2,7 +2,7 @@ import { Events } from 'discord.js';
 import { createEvent } from '@/common/events/create-event.js';
 import { config } from '@/env.js';
 import { initializeAdventScheduler } from '@/util/advent-scheduler.js';
-import { fetchAndCachePublicChannelsMessages } from '@/util/cache.js';
+import { fetchAndCachePublicChannelsMessages } from '@/util/channel-prefetch.js';
 import { syncGuidesToChannel } from '@/util/post-guides.js';
 import { leaveIfNotAllowedServer } from '@/util/server-guard.js';
 import { syncArchiveCategoryChannels } from '../archive-channels/util.js';

src/features/report-message/index.ts

@@ -0,0 +1,70 @@
+import { createMessageContextMenuCommand } from '@/common/commands/create-commands.js';
+import { config } from '@/env.js';
+import { ChannelType, Colors, EmbedBuilder, MessageFlags } from 'discord.js';
+
+export const reportMessage = createMessageContextMenuCommand({
+  data: {
+    name: 'Report to Moderators',
+  },
+  execute: async (interaction) => {
+    await interaction.deferReply({
+      flags: MessageFlags.Ephemeral,
+    });
+
+    const guild = interaction.guild;
+
+    if (!guild) {
+      await interaction.editReply({
+        content: 'This can only be used in a server.',
+      });
+      return;
+    }
+
+    const targetMessage = interaction.targetMessage;
+    const reporter = interaction.user;
+    const channelId = config.channelIds.spamDetection;
+    const channel = guild.channels.cache.get(channelId);
+
+    try {
+      if (!channel || channel.type !== ChannelType.GuildText) {
+        await interaction.editReply({
+          content: 'Moderator channel not found or is not a text channel.',
+        });
+        return;
+      }
+
+      const jumpLink = targetMessage.url;
+      const authorTag = targetMessage.author.tag ?? 'Unknown';
+      const authorId = targetMessage.author.id ?? 'Unknown';
+
+      const embed = new EmbedBuilder()
+        .setTitle('🚩 Message Report')
+        .setColor(Colors.DarkOrange)
+        .setTimestamp()
+        .setURL(jumpLink)
+        .addFields(
+          { name: 'Reporter', value: `<@${reporter.id}>`, inline: true },
+          {
+            name: 'Message Link',
+            value: `[Jump to message](${jumpLink})`,
+            inline: true,
+          },
+          { name: 'Message ID', value: targetMessage.id, inline: true },
+          { name: 'Username', value: authorTag, inline: true },
+          { name: 'User ID', value: authorId, inline: true },
+          { name: 'Linked User', value: `<@${authorId}>`, inline: true }
+        );
+
+      await channel.send({ embeds: [embed] });
+
+      await interaction.editReply({
+        content: 'Thanks. The message was reported to moderators.',
+      });
+    } catch (error) {
+      console.error(error);
+      await interaction.editReply({
+        content: 'Failed to report the message.',
+      });
+    }
+  },
+});

src/features/spam-detection/actions.ts

@@ -0,0 +1,115 @@
+import type { Channel, Message } from 'discord.js';
+import { cachedMessages } from '@/util/cache/recent-message-store.js';
+import { DAY, HOUR } from '../../constants/time.js';
+import { defaultLogFunction, type LogFunction } from './logs.js';
+import type { Rule } from './rules-config.js';
+
+type ActionConfig = {
+  reason: string;
+  deleteMessages?: boolean;
+  muteDuration?: number;
+  log?: LogFunction;
+};
+
+const handleBulkDeleteMessages = async (messages: Message[]) => {
+  const messagesByChannel = new Map<string, string[]>();
+  for (const message of messages) {
+    if (!message.deletable || !message.inGuild()) {
+      continue;
+    }
+    if (!messagesByChannel.has(message.channelId)) {
+      messagesByChannel.set(message.channelId, [message.id]);
+    } else {
+      messagesByChannel.get(message.channelId)!.push(message.id);
+    }
+  }
+
+  let deletedMessagesCount = 0;
+
+  await Promise.allSettled(
+    Array.from(messagesByChannel.entries()).map(([channelId, messageIds]) => {
+      const channel = messages.find(
+        (message) => message.channelId === channelId
+      )?.channel;
+      if (!channel || channel.isDMBased()) {
+        return Promise.resolve();
+      }
+      cachedMessages.bulkDeleteByIds(messageIds);
+      deletedMessagesCount += messageIds.length;
+      return channel.bulkDelete(messageIds, true);
+    })
+  );
+
+  return deletedMessagesCount;
+};
+
+const handleAction = (config: ActionConfig) => {
+  return async (messages: Message[], rule: Rule, logChannel?: Channel) => {
+    const firstMessage = messages[0];
+    const author = firstMessage.author;
+
+    if (author === undefined) {
+      return;
+    }
+
+    let muted = false;
+    if (config.muteDuration) {
+      try {
+        const guildMember = await firstMessage.guild?.members.fetch(author.id);
+        if (guildMember?.moderatable) {
+          await guildMember.timeout(config.muteDuration, config.reason);
+          muted = true;
+        }
+      } catch (error) {
+        console.error('Failed to mute user:', error);
+      }
+    }
+
+    let deletedMessagesCount = 0;
+
+    if (config.deleteMessages) {
+      deletedMessagesCount = await handleBulkDeleteMessages(messages);
+    }
+
+    // Use custom log function if provided, otherwise use default
+    const logFunction = config.log || defaultLogFunction;
+    await logFunction({
+      messages,
+      reason: config.reason,
+      logChannel,
+      deletedMessagesCount,
+      muteDuration: muted ? config.muteDuration : undefined,
+      rule,
+    });
+  };
+};
+
+export const handleBannedTagsAction = handleAction({
+  reason: 'Banned Tag',
+  deleteMessages: true,
+  muteDuration: 1 * DAY,
+});
+
+export const handleDiscordInvitesAction = handleAction({
+  reason: 'Discord Invite Link',
+  deleteMessages: true,
+  muteDuration: 1 * DAY,
+});
+
+export const handleSpoilerHackAction = handleAction({
+  reason: 'Spoiler Tag Hack',
+  deleteMessages: true,
+  muteDuration: 12 * HOUR,
+});
+
+export const handleCrossPostingAction = handleAction({
+  reason: 'Cross-posting',
+  deleteMessages: true,
+  muteDuration: 12 * HOUR,
+});
+
+export const handleHighFrequencyAction = handleAction({
+  reason: 'High Frequency Messaging',
+  deleteMessages: true,
+  muteDuration: 12 * HOUR,
+});

src/features/spam-detection/constants.ts

@@ -0,0 +1,9 @@
+import { rules } from './rules-config.js';
+
+export const MAX_RULE_TIMEFRAME = Math.max(
+  ...rules
+    .filter((rule) => rule.type !== 'contentBased')
+    .map((rule) => rule.timeframe)
+);
+
+export const MESSAGE_SIMILARITY_THRESHOLD = 0.8;

src/features/spam-detection/detectors.ts

@@ -0,0 +1,51 @@
+import type { Message } from 'discord.js';
+import { jaccardSimilarity } from '@/util/text.js';
+import { replaceSpoilerHack } from '@/util/text.js';
+import { stripCode } from '@/util/text.js';
+import { MESSAGE_SIMILARITY_THRESHOLD } from './constants.js';
+
+export const containsLink = (message: Message): boolean => {
+  const withoutCode = stripCode(message.content);
+  return withoutCode.includes('http://') || withoutCode.includes('https://');
+};
+
+export const containsBannedTag = (message: Message): boolean => {
+  const withoutCode = stripCode(message.content);
+  return withoutCode.includes('@everyone') || withoutCode.includes('@here');
+};
+
+export const containsDiscordInvite = (message: Message): boolean => {
+  const withoutCode = stripCode(message.content);
+  const keywords = [
+    'discord.gg/',
+    'discord.com/invite/',
+    'discordapp.com/invite/',
+  ];
+  return keywords.some((keyword) => withoutCode.includes(keyword));
+};
+
+export const containsSpoilerHack = (message: Message) => {
+  const withoutCode = stripCode(message.content);
+
+  return withoutCode !== replaceSpoilerHack(withoutCode, '');
+};
+
+export const isDuplicate = (message: Message, oldMessage: Message) => {
+  // cheaper comparison first
+  const content = message.content.toLowerCase().trim();
+  const oldContent = oldMessage.content.toLowerCase().trim();
+  if (content === oldContent) {
+    return true;
+  }
+  // followed by jaccard for catching reordered/slightly altered messages with high similarity
+  return jaccardSimilarity(content, oldContent) > MESSAGE_SIMILARITY_THRESHOLD;
+};
+
+export const isCrossPost = (message: Message, oldMessage: Message) => {
+  return (
+    message.channelId !== oldMessage.channelId &&
+    isDuplicate(message, oldMessage)
+  );
+};
+
+export const anyMessage = () => true;

src/features/spam-detection/index.ts

@@ -0,0 +1,28 @@
+import { Events } from 'discord.js';
+import { cachedMessages } from '@/util/cache/recent-message-store.js';
+import { config } from '@/env.js';
+import { createEvent } from '@/common/events/create-event.js';
+import { checkRules } from './rules.js';
+import { isNormalUserMessage } from '@/util/messages.js';
+
+export const spamDetection = createEvent(
+  {
+    name: Events.MessageCreate,
+  },
+  async (message) => {
+    if (!isNormalUserMessage(message)) {
+      return;
+    }
+    const regularRole = message.guild?.roles.cache.get(config.roleIds.regular);
+    if (
+      regularRole === undefined ||
+      message.member === null ||
+      message.member.roles.highest.position >= regularRole.position
+    ) {
+      return;
+    }
+
+    cachedMessages.add(message);
+    await checkRules(message);
+  }
+);