/**
 * apps/worker — ioredis factory.
 *
 * `createRedis()` builds the shared connection. BullMQ requirements:
 * `maxRetriesPerRequest: null` (long-running workers must not let ioredis
 * abort in-flight commands during a Redis failover). `lazyConnect: false`
 * so failures surface immediately at startup. Connection errors are logged
 * (warn) instead of crashing — ioredis retries with backoff on its own.
 */
import { Redis } from "ioredis";
import { getLogger } from "../logger.js";

const log = getLogger("redis");

let shared: Redis | null = null;

export function createRedis(url: string): Redis {
  const redis = new Redis(url, {
    maxRetriesPerRequest: null, // REQUIRED by BullMQ
    lazyConnect: false,
    enableReadyCheck: true,
    retryStrategy: (times) => Math.min(times * 200, 5000)
  });

  redis.on("error", (err: Error) => {
    log.warn({ err: err.message }, "redis connection error (auto-retrying)");
  });
  redis.on("connect", () => log.debug("redis connected"));
  redis.on("ready", () => log.debug("redis ready"));
  redis.on("reconnecting", (ms: number) => log.warn(`redis reconnecting in ${ms}ms`));
  return redis;
}

/** Shared instance for the whole process (workers + consumers + heartbeat). */
export function getRedis(url: string): Redis {
  if (!shared) shared = createRedis(url);
  return shared;
}

export async function closeRedis(): Promise<void> {
  if (shared) {
    await shared.quit().catch(() => shared!.disconnect());
    shared = null;
  }
}