import Redis from "ioredis";

const globalForRedis = globalThis as unknown as { redis?: Redis | null };

function createRedis(): Redis | null {
  const url = process.env.REDIS_URL;
  if (!url) return null;
  try {
    const client = new Redis(url, {
      maxRetriesPerRequest: 3,
      retryStrategy(times) {
        if (times > 3) return null;
        return Math.min(times * 200, 2000);
      },
      lazyConnect: true,
    });
    client.on("error", () => {});
    return client;
  } catch {
    return null;
  }
}

export const redis: Redis | null =
  globalForRedis.redis !== undefined ? globalForRedis.redis : (globalForRedis.redis = createRedis());

export async function withRedis<T>(
  fallback: () => Promise<T>,
  redisFn: (client: Redis) => Promise<T>,
): Promise<T> {
  if (redis) {
    try {
      return await redisFn(redis);
    } catch {
      return fallback();
    }
  }
  return fallback();
}