feat: add editing support to InternalPoster

backend/src/plugins/InternalPoster/functions/editMessage.ts

@@ -0,0 +1,46 @@
+import { Message, MessageOptions, NewsChannel, TextChannel, WebhookClient } from "discord.js";
+import { GuildPluginData } from "knub";
+import { InternalPosterPluginType } from "../types";
+import { isDiscordAPIError, noop } from "../../../utils";
+
+/**
+ * Sends a message using a webhook or direct API requests, preferring webhooks when possible.
+ */
+export async function editMessage(
+  pluginData: GuildPluginData<InternalPosterPluginType>,
+  message: Message,
+  content: MessageOptions,
+): Promise<void> {
+  if (!(message.channel instanceof TextChannel || message.channel instanceof NewsChannel)) {
+    return;
+  }
+
+  const channel = message.channel as TextChannel | NewsChannel;
+
+  await pluginData.state.queue.add(async () => {
+    if (message.webhookId) {
+      const webhook = await pluginData.state.webhooks.find(message.webhookId);
+      if (!webhook) {
+        // Webhook message but we're missing the token -> can't edit
+        return;
+      }
+
+      const webhookClient = new WebhookClient({
+        id: webhook.id,
+        token: webhook.token,
+      });
+      await webhookClient.editMessage(message.id, content).catch(async (err) => {
+        // Unknown Webhook, remove from DB
+        if (isDiscordAPIError(err) && err.code === 10015) {
+          await pluginData.state.webhooks.delete(webhookClient.id);
+          return;
+        }
+
+        throw err;
+      });
+      return;
+    }
+
+    await message.edit(content).catch(noop);
+  });
+}