import type { RequestHandler } from './$types';
import { getDb } from '$lib/server/db';
import { findActiveToken, createCalendarTokenUrl, buildCalendarIcsUrl } from '$lib/server/calendar-tokens';

export const GET: RequestHandler = async (event) => {
  // Requiere sesión
  const userId = event.locals.userId ?? null;
  if (!userId) {
    return new Response('Unauthorized', { status: 401 });
  }

  const db = await getDb();

  // Listar solo grupos permitidos donde el usuario está activo (mismo gating que /api/me/groups)
  const groups = db
    .prepare(
      `SELECT g.id, g.name
       FROM groups g
       INNER JOIN group_members gm
         ON gm.group_id = g.id AND gm.user_id = ? AND gm.is_active = 1
       INNER JOIN allowed_groups ag
         ON ag.group_id = g.id AND ag.status = 'allowed'
       WHERE COALESCE(g.active, 1) = 1
       ORDER BY (g.name IS NULL) ASC, g.name ASC, g.id ASC`
    )
    .all(userId) as Array<{ id: string; name: string | null }>;

  // Personal
  const personalExisting = await findActiveToken('personal', userId, null);
  const personal =
    personalExisting
      ? { url: personalExisting.token_plain ? buildCalendarIcsUrl('personal', personalExisting.token_plain) : null }
      : await (async () => {
          const created = await createCalendarTokenUrl('personal', userId, null);
          return { url: created.url };
        })();

  // Aggregate (multigrupo)
  const aggregateExisting = await findActiveToken('aggregate', userId, null);
  const aggregate =
    aggregateExisting
      ? { url: aggregateExisting.token_plain ? buildCalendarIcsUrl('aggregate', aggregateExisting.token_plain) : null }
      : await (async () => {
          const created = await createCalendarTokenUrl('aggregate', userId, null);
          return { url: created.url };
        })();

  // Por grupo (B): autogenerar si falta
  const groupFeeds: Array<{ groupId: string; groupName: string | null; url: string | null }> = [];
  for (const g of groups) {
    const ex = await findActiveToken('group', userId, g.id);
    if (ex) {
      const url = ex.token_plain ? buildCalendarIcsUrl('group', ex.token_plain) : null;
      groupFeeds.push({ groupId: g.id, groupName: g.name ?? null, url });
    } else {
      const created = await createCalendarTokenUrl('group', userId, g.id);
      groupFeeds.push({ groupId: g.id, groupName: g.name ?? null, url: created.url });
    }
  }

  const body = {
    personal,
    groups: groupFeeds,
    aggregate
  };

  return new Response(JSON.stringify(body), {
    status: 200,
    headers: { 'content-type': 'application/json; charset=utf-8', 'cache-control': 'no-store' }
  });
};