feat: initial prototype (#1)

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Reviewed-on: #1
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/modules/checkAltText.ts

@@ -0,0 +1,34 @@
+/**
+ * @copyright NHCarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+
+import { reminders } from "../config/reminders.js";
+import { getRandomValue } from "../utils/getRandomValue.js";
+import type { Message } from "discord.js";
+
+/**
+ * Checks if a message has image attachments, and
+ * if those attachments have alt text.
+ * @param message - The message payload from Discord.
+ */
+export const checkAltText = async(message: Message): Promise<void> => {
+  if (message.attachments.size <= 0) {
+    return;
+  }
+
+  const images = message.attachments.filter((attachment) => {
+    return attachment.contentType?.startsWith("image/");
+  });
+  const noDescription = images.filter((image) => {
+    return image.description === null;
+  });
+
+  if (noDescription.size > 0) {
+    const reminder = getRandomValue(reminders);
+    await message.reply({
+      content: reminder,
+    });
+  }
+};