Detect blocked words on channel creation

src/events/channelCreate.ts

@@ -0,0 +1,109 @@
+import client from "../client";
+import { AuditLogEvent, Events, GuildAuditLogsEntry, PermissionFlagsBits, User } from "discord.js";
+import { getGuildSetting } from "../tools/data";
+import { Badword, database } from "../data";
+import { IsNull } from "typeorm";
+import getDefaultEmbed, { getFailedEmbed } from "../tools/defaultEmbeds";
+import { getGuildChannel } from "../tools/discord";
+import { Color, Emoji } from "../tools/design";
+
+client.on(Events.ChannelCreate, async (newChannel) => {
+    if (newChannel.isDMBased()) return;
+    const name = newChannel.name.toLowerCase();
+
+    const guild = newChannel.guild;
+    const settings = await getGuildSetting(guild.id);
+
+    const globalBlocklist = await database.getRepository(Badword).find({
+        where: {
+            guildID: IsNull()
+        }
+    });
+    const localBlocklist = await database.getRepository(Badword).find({
+        where: {
+            guildID: guild.id
+        }
+    });
+
+    const blocklist = [...globalBlocklist, ...localBlocklist];
+    let found: string | null = null;
+
+    for (let i = 0; i < blocklist.length; i++) {
+        const word = blocklist[i];
+        if (!word) continue;
+
+        if (!name.includes(word.value)) continue;
+        found = word.value;
+        break;
+    }
+
+    if (found === null) return;
+
+    let responsibleUser: User | null;
+
+    try {
+        const clientMember = await guild.members.fetchMe();
+        const canSeeAuditLog = clientMember.permissions.has(PermissionFlagsBits.ViewAuditLog);
+        const auditLogs = canSeeAuditLog ? await guild.fetchAuditLogs({
+            type: AuditLogEvent.ChannelCreate,
+            limit: 50
+        }) : undefined;
+
+        const change = auditLogs?.entries.filter((entry) => {
+            if (entry.target.id !== newChannel.id) return false;
+
+            return entry.changes.filter((change) => {
+                return change.key === "name" && change.new === newChannel.name;
+            }).length > 0;
+        }).reduce<null | GuildAuditLogsEntry<AuditLogEvent.ChannelCreate, "Create", "Channel", AuditLogEvent.ChannelCreate>>((unknown, curr) => {
+            if (!unknown) return curr;
+            const prev = unknown as GuildAuditLogsEntry<AuditLogEvent.ChannelCreate, "Create", "Channel", AuditLogEvent.ChannelCreate>
+            return curr.createdTimestamp > prev.createdTimestamp ? curr : prev;
+        }, null);
+
+        responsibleUser = change?.executor || null;
+    } catch (error) {
+        responsibleUser = null;
+    }
+
+    const logChannel = settings.notificationChannelID ? await getGuildChannel(guild.id, settings.notificationChannelID) : null;
+
+    try {
+        if (!newChannel.deletable) throw new Error("Missing permissions to delete channel");
+        await newChannel.delete("[Automated] Detected blocked word in channel name");
+    } catch (error) {
+        if (!logChannel || !logChannel.isTextBased()) return;
+        const embed = getFailedEmbed();
+        embed.setDescription(`Couldn't delete <#${newChannel.id}> (${newChannel.id}): ${error instanceof Error ? error.message : error}`);
+        embed.addFields({
+            name: "Detected banned word:",
+            value: `||${found}||`
+        }, {
+            name: "Channel created by:",
+            value: responsibleUser ? `${responsibleUser.tag} (${responsibleUser.id})` : "`Couldn't detect responsible user :(`"
+        });
+
+        logChannel.send({
+            embeds: [embed]
+        }).catch(() => {});
+        return;
+    }
+
+    if (!logChannel || !logChannel.isTextBased()) return;
+    const embed = getDefaultEmbed();
+    embed.setTitle(`${Emoji.SECURITY_CHALLENGE_FAILED} Blocked word detected`);
+    embed.setDescription(`||#${newChannel.name}|| (${newChannel.id}) has been deleted because its name contained a blocked word.`);
+    embed.setColor(Color.WARNING_YELLOW);
+    embed.addFields({
+        name: "Detected banned word:",
+        value: `||${found}||`,
+        inline: true
+    }, {
+        name: "Channel created by:",
+        value: responsibleUser ? `${responsibleUser.tag} (${responsibleUser.id})` : "`Couldn't detect responsible user :(`"
+    });
+
+    logChannel.send({
+        embeds: [embed]
+    }).catch(() => {});
+});

src/events/index.ts

@@ -1,2 +1,3 @@
 import "./channelUpdate";
 import "./guildDelete";
+import "./channelCreate";