import { inArray, sum } from "drizzle-orm";
import { apiJson } from "@/lib/api";
import { db, RadioListenerPoints, User } from "@/lib/db";

// Radio listener-points leaderboard: the top 20 users by total points, summed
// across radio_listener_points and joined to users for username/look. Public
// (no auth) — mirrors the AtomCMS radio leaderboard widget.
export const dynamic = "force-dynamic";

export async function GET(_req: Request) {
	try {
		// Sum points per user. Sort/slice in JS so we stay adapter-agnostic about
		// aggregate ordering, then resolve the top 20 to usernames/looks.
		const grouped = await db
			.select({
				userId: RadioListenerPoints.userId,
				points: sum(RadioListenerPoints.points),
			})
			.from(RadioListenerPoints)
			.groupBy(RadioListenerPoints.userId);

		const ranked = grouped
			.map((g) => ({
				userId: Number(g.userId),
				points: Number(g.points ?? 0),
			}))
			.sort((a, b) => b.points - a.points)
			.slice(0, 20);

		if (ranked.length === 0) {
			return apiJson({ data: [] });
		}

		const userIds = ranked.map((r) => r.userId);
		const users = await db
			.select({ id: User.id, username: User.username, look: User.look })
			.from(User)
			.where(inArray(User.id, userIds));
		const userById = new Map(users.map((u) => [u.id, u]));

		const data = ranked.map((r) => {
			const u = userById.get(r.userId);
			return {
				username: u?.username ?? null,
				look: u?.look ?? null,
				points: r.points,
			};
		});

		return apiJson({ data });
	} catch {
		// DB unavailable — serve an empty leaderboard rather than a 500.
		return apiJson({ data: [] }, { status: 200 });
	}
}