import type { Hono } from "hono";
import { html } from "../pages/html.ts";
import { relativeTime } from "../pages/layout.ts";
import { NOTIFICATION_KINDS, type NotificationKind, setting } from "../server/db.ts";
import { type AdminContext, adminPage, formField, textFields } from "./console.ts";
import { saveSettings } from "./store.ts";

type Notification = { id: number; text: string; href: string; created_at: number; read: number };

export const LABELS: Record<NotificationKind, string> = {
	issue_filed: "an issue is filed",
	issue_followup: "someone replies to an issue",
	sync_failed: "a repo's sync starts failing",
	backup_failed: "a backup starts failing",
};

/** §24's Notifications section: the list, opening one, mark all read, and which kinds to raise. */
export function registerNotifications(app: Hono, ctx: AdminContext): void {
	app.get("/admin/notifications", (c) => {
		if (c.req.query("format") === "json") {
			const unread =
				ctx.kepr
					.query<{ n: number }, []>("SELECT COUNT(*) AS n FROM notifications WHERE read = 0")
					.get()?.n ?? 0;
			const recent = ctx.kepr
				.query<Notification, []>(
					"SELECT id, text, href, created_at, read FROM notifications ORDER BY id DESC LIMIT 5",
				)
				.all();
			return c.json({
				unread,
				notifications: recent.map(({ id, text, created_at, read }) => ({
					id,
					text,
					read,
					when: relativeTime(created_at),
				})),
			});
		}

		const rows = ctx.kepr
			.query<Notification, []>(
				"SELECT id, text, href, created_at, read FROM notifications ORDER BY id DESC",
			)
			.all();
		const row = (n: Notification) =>
			html`<a class="issue-row${n.read ? "" : " notification-unread"}" href="/admin/notifications/${String(n.id)}">
<span class="issue-title">${n.text}</span>
<span class="issue-meta mono">${n.read ? "" : "unread · "}${relativeTime(n.created_at)}</span></a>`;
		const kind = (k: NotificationKind) =>
			html`<label class="issues-label"><input type="checkbox" name="${k}" value="1"${
				setting(ctx.kepr, `notify_off_${k}`) ? "" : html` checked`
			}> ${LABELS[k]}</label>`;
		const body = html`<form method="post" action="/admin/notifications">
${formField(c)}<input type="hidden" name="action" value="read_all">
<button class="issues-submit" type="submit">mark all read</button></form>
<section class="repo-section">
${rows.length > 0 ? rows.map(row) : html`<p class="muted mono save-empty">nothing yet</p>`}
</section>
<section class="repo-section"><h2 class="section-label mono">tell me when</h2>
<form class="issues-form" method="post" action="/admin/notifications">
${formField(c)}<input type="hidden" name="action" value="preferences">
${NOTIFICATION_KINDS.map(kind)}
<button class="issues-submit" type="submit">save</button>
</form></section>`;
		return c.html(adminPage(c, ctx, "notifications", body));
	});

	app.get("/admin/notifications/:id{[0-9]{1,9}}", (c) => {
		const found = ctx.kepr
			.query<{ href: string }, [number]>(
				"UPDATE notifications SET read = 1 WHERE id = ? RETURNING href",
			)
			.get(Number(c.req.param("id")));
		return found ? c.redirect(found.href, 303) : c.notFound();
	});

	app.post("/admin/notifications", async (c) => {
		const fields = await textFields(c);
		if (fields.action === "read_all") {
			ctx.kepr.run("UPDATE notifications SET read = 1 WHERE read = 0");
		} else if (fields.action === "preferences") {
			// A box left unticked is a kind switched off; the setting records only that.
			saveSettings(
				ctx.kepr,
				Object.fromEntries(
					NOTIFICATION_KINDS.map((k) => [`notify_off_${k}`, fields[k] === "1" ? "" : "1"]),
				),
			);
		} else return c.text("Unknown action.", 400);
		return c.redirect("/admin/notifications?saved=1", 303);
	});
}