refactor split board update and notifications to their modules

src/lib/board.ts

@@ -0,0 +1,27 @@
+import { Client, EmbedBuilder } from "npm:discord.js";
+
+import { fetch_feed_channel, format_devoir_title } from "./lib.ts";
+import { Storage } from "./storage.ts";
+import { Channel, collect, log_from } from "./utils.ts";
+
+const log = log_from(import.meta);
+
+export async function update_loop(bot: Client, storage: Storage, update_display: Channel) {
+	log("Waiting for updates.");
+	while (true) {
+		const _trigger = await update_display.receive();
+		log("Updating board.");
+		for await (const [_, feed] of storage.feeds.list()) {
+			const feed_channel = await fetch_feed_channel(bot, feed);
+			const embed = new EmbedBuilder().setTitle("`📚` Devoirs")
+				.setFooter({ text: "Mise à jour " + Date.now() });
+			const sorted_devoirs = (await (collect(storage.devoirs.list())))
+				.map(([_, d]) => d).toSorted((a, b) => a.date > b.date ? 1 : -1);
+			for (const devoir of sorted_devoirs) {
+				embed.addFields({ name: format_devoir_title(devoir), value: devoir.description });
+			}
+			const board_message = await feed_channel.messages.fetch(feed.board_message_id);
+			board_message.edit({ embeds: [embed], content: "" });
+		}
+	}
+}