import { json, readJsonBody, requireAdmin } from "../../../../_lib/auth";
import { addCalendarDays, organizerDate, readCalendar } from "../../../../_lib/calendar-feed";
import { readSettings, validCalendarUrl } from "../../../../_lib/store";

export const dynamic = "force-dynamic";

/** Fetches one feed (saved by id, or a not-yet-saved URL) and reports what it found. */
export async function POST(request: Request) {
  const denied = await requireAdmin(request, { mutating: true });
  if (denied) return denied;
  const body = await readJsonBody<{ id?: string; url?: string }>(request);
  let url: string | null = null;
  if (body?.url) url = validCalendarUrl(body.url);
  else if (body?.id) url = (await readSettings()).calendars.find((calendar) => calendar.id === body.id)?.url ?? null;
  if (!url) return json({ ok: false, error: "Not a Google Calendar basic.ics address." }, 400);

  const now = Date.now();
  const today = organizerDate(new Date(now));
  try {
    const result = await readCalendar(
      url,
      { feedIndex: 0, tone: "cyan", nameOverride: "" },
      now,
      now + 60 * 24 * 60 * 60 * 1_000,
      today,
      addCalendarDays(today, 60),
    );
    return json({ ok: true, sourceName: result.sourceName, eventCount: result.eventCount, upcoming: result.items.length });
  } catch (error) {
    return json({ ok: false, error: error instanceof Error ? error.message : "Fetch failed" });
  }
}