const gtfs = require("./gtfsData"); 
const redis = require("./redisDAL");

const CACHE_PREFIX = "gtfs_cache";
const RT_TTL = 3;           
const STATIC_TTL = 24 * 3600; 

async function getCached(keySuffix, fetchFn, ttl) {
  await redis.connect();

  const cached = await redis.get(CACHE_PREFIX, { key: keySuffix });
  if (cached !== null) return cached;

  const data = await fetchFn();
  await redis.set(CACHE_PREFIX, { key: keySuffix }, data, ttl);
  return data;
}

async function getTrains() {
  return getCached("trains", gtfs.getTrains, RT_TTL);
}

async function getBuses() {
  return getCached("buses", gtfs.getBuses, RT_TTL);
}

async function getTrainsByRoute(route) {
  return getCached(`trains_route_${route}`, () => gtfs.getTrainsByRoute(route), RT_TTL);
}

async function getBusesByRoute(route) {
  return getCached(`buses_route_${route}`, () => gtfs.getBusesByRoute(route), RT_TTL);
}

async function getAlerts() {
  return getCached("alerts", gtfs.getAlerts, RT_TTL);
}

async function getAlertsByRoute(route) {
  return getCached(`alerts_route_${route}`, () => gtfs.getAlertsByRoute(route), RT_TTL);
}

async function getScheduleByRoute(route) {
  return getCached(`schedule_route_${route}`, () => gtfs.getScheduleByRoute(route), RT_TTL);
}

async function getScheduleByStationId(stopId) {
  return getCached(`schedule_stop_${stopId}`, () => gtfs.getScheduleByStationId(stopId), RT_TTL);
}

async function getRoutes() {
  return getCached("routes", gtfs.getRoutes, STATIC_TTL);
}

async function getStops() {
  return getCached("stops", gtfs.getStops, STATIC_TTL);
}

async function getStopsByRoute(route) {
  return getCached(`stops_route_${route}`, () => gtfs.getStopsByRoute(route), STATIC_TTL);
}

async function getShapeByRoute(route) {
  return getCached(`shape_route_${route}`, () => gtfs.getShapeByRoute(route), STATIC_TTL);
}

async function updateGtfsRt() {
  const data = await gtfs.updateGtfsRt();
  await redis.set(CACHE_PREFIX, { key: "trains" }, await gtfs.getTrains(), RT_TTL);
  await redis.set(CACHE_PREFIX, { key: "buses" }, await gtfs.getBuses(), RT_TTL);
  await redis.set(CACHE_PREFIX, { key: "alerts" }, await gtfs.getAlerts(), RT_TTL);
  return data;
}

async function loadGtfsStaticInMemory() {
  const data = await gtfs.loadGtfsStaticInMemory();
  await redis.set(CACHE_PREFIX, { key: "routes" }, data.routes || [], STATIC_TTL);
  await redis.set(CACHE_PREFIX, { key: "stops" }, data.stops || [], STATIC_TTL);
  return data;
}

const { gtfs_rt_v, gtfs_rt_t, gtfs_rt_a } = gtfs;

module.exports = {
  getStops,
  getStopsByRoute,
  getRoutes,
  getTrains,
  getBuses,
  getTrainsByRoute,
  getBusesByRoute,
  getAlerts,
  getAlertsByRoute,
  getScheduleByRoute,
  getScheduleByStationId,
  getShapeByRoute,
  updateGtfsRt,
  loadGtfsStaticInMemory,
};