/**
 * Centralized env parsing — validate at startup, fail fast on bad config.
 * Other modules read from the frozen `config` object instead of process.env
 * so misconfiguration shows up here, not deep in a request handler.
 */

import { parseStalenessHours } from "../../lib/env";

function parsePort(raw: string | undefined, fallback: number): number {
  if (!raw) return fallback;
  const n = parseInt(raw, 10);
  if (!Number.isFinite(n) || n < 1 || n > 65535) {
    throw new Error(`Invalid PORT=${raw}: must be an integer in 1..65535`);
  }
  return n;
}

export const config = Object.freeze({
  port: parsePort(process.env.PORT, 3001),
  parkHoursStalenessHours: parseStalenessHours(process.env.PARK_HOURS_STALENESS_HOURS, 72),
  nodeEnv: process.env.NODE_ENV ?? "development",
  rateLimitPerMin: parsePort(process.env.RATE_LIMIT_PER_MIN, 60),
});

export type Config = typeof config;