From 544b2669ca1b8b7f81521ac502282d7402769cc4 Mon Sep 17 00:00:00 2001
From: JandereDev <me@janderedev.xyz>
Date: Sat, 23 Oct 2021 16:04:06 +0200
Subject: [PATCH] purge command

---
 src/bot/commands/purge.ts | 89 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 src/bot/commands/purge.ts

diff --git a/src/bot/commands/purge.ts b/src/bot/commands/purge.ts
new file mode 100644
index 0000000..e134d15
--- /dev/null
+++ b/src/bot/commands/purge.ts
@@ -0,0 +1,89 @@
+import Command from "../../struct/Command";
+import { Message } from "revolt.js/dist/maps/Messages";
+import { decodeTime } from 'ulid';
+import { isModerator, parseUser } from "../util";
+
+const SYNTAX = '/purge [SELECTOR] [@user?[m @user?[, ...]]]; where SELECTOR: [number] || [messageID]-[messageID]';
+const MAX_PURGE_AMOUNT = 100;
+
+export default {
+    name: 'purge',
+    aliases: [ 'clear' ],
+    description: 'delete multiple messages at once',
+    syntax: SYNTAX,
+    run: async (message: Message, args: string[]) => {
+        try {
+            if (!message.member || !await isModerator(message.member!)) return message.reply('🔒 Access denied');
+
+            let messages: Array<Message> = [];
+            // X amount of messages from bottom
+            if (/^[0-9]+$/g.test(args[0])) {
+                let amount = Number(args[0]);
+                if (isNaN(amount)) return message.reply('Invalid number');
+                if (amount > MAX_PURGE_AMOUNT) return message.reply(`Message count exceeds the limit of ${MAX_PURGE_AMOUNT}.`);
+
+                messages = await message.channel!.fetchMessages({
+                    limit: amount
+                });
+            }
+            // delete messages between [id] and [id]
+            // [0-9A-HJ-KM-NP-TV-Z]{26} -> matches ULIDs
+            else if (/^[0-9A-HJ-KM-NP-TV-Z]{26}-[0-9A-HJ-KM-NP-TV-Z]{26}$/g.test(args[0])) {
+                let [id1, id2] = args[0].split('-');
+
+                let [msg1, msg2] = await Promise.all([
+                    message.channel!.fetchMessage(id1),
+                    message.channel!.fetchMessage(id2),
+                ]);
+
+                // Make sure the msg1 and msg2 are in the correct order
+                if (decodeTime(msg1._id) < decodeTime(msg2._id)) {
+                    [msg1, msg2] = [msg2, msg1];
+                }
+
+                messages = await message.channel!.fetchMessages({
+                    before: id2,
+                    after: id1,
+                    limit: MAX_PURGE_AMOUNT,
+                    sort: 'Latest',
+                });
+
+                if (!messages.find(m => m._id == msg1._id)) messages = [ msg1, ...messages ];
+                if (!messages.find(m => m._id == msg2._id)) messages = [ ...messages, msg2 ];
+
+                // Discard messages that are not in the selected range,
+                // because Revolt returns more messages than expected for some reason
+                messages = messages.filter(
+                    m => decodeTime(m._id) <= decodeTime(id2) &&
+                         decodeTime(m._id) >= decodeTime(id1)
+                );
+            }
+            // allow single messages too, because why not?
+            else if (/^[0-9A-HJ-KM-NP-TV-Z]{26}$/g.test(args[0])) {
+                messages = [ await message.channel!.fetchMessage(args[0]) ];
+            } else {
+                return message.reply(`I can't parse that message range.\nSyntax: \`${SYNTAX}\``);
+            }
+
+            if (args[1]) {
+                let p = args[1].split(',').map(u => parseUser(u));
+                let users = await Promise.all(p);
+
+                if (users.filter(u => !u).length > 0)
+                    return message.reply('At least one of the supplied users could not be found.');
+
+                messages = messages.filter(m => users.find(u => u?._id == m.author_id));
+            }
+
+            let m = await message.reply(`Deleting ${messages.length} messages...`);
+            let res = await Promise.allSettled(messages.map(m => m.delete()));
+
+            let failures = res.filter(r => r.status == 'rejected').length;
+
+            await m?.edit({ content: `Deleted ${messages.length} messages.`
+                + `${failures > 0 ? `\n${failures} message${failures == 1 ? '' : 's'} failed to delete.` : ''}` });
+        } catch(e) {
+            message.reply(`An error has occurred: ${e}`);
+        }
+    }
+} as Command;