import "server-only";

import Redis from "ioredis";

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

function createRedis(): Redis | null {
	const url = process.env.REDIS_URL;
	if (!url) {
		if (
			process.env.NODE_ENV === "production" &&
			!globalForRedis.redisMissingWarned
		) {
			globalForRedis.redisMissingWarned = true;
			console.error(
				"[redis] REDIS_URL is unset in production. Rate limits and shared caches fall back to in-process memory and will not work correctly across multiple instances.",
			);
		}
		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 : createRedis();
if (globalForRedis.redis === undefined) globalForRedis.redis = redis;