import { randomUUID } from "node:crypto";

import Redis from "ioredis";
import { afterAll, beforeAll, describe, expect, it } from "vitest";

import { CATALOG_CACHE_TAG, GLOSSARY_CACHE_TAG, pageCacheTag } from "@/lib/cache/tags";
import { parseInvalidationEvent } from "@/lib/events/invalidation";
import {
  createRedisOutboxTransport,
  processOutboxEvent,
} from "@/lib/outbox/processor";
import {
  redisCacheTagStateKey,
  redisEventChannel,
} from "@/lib/redis/client";

const integrationUrl = process.env.REDIS_INTEGRATION_URL;
const describeWithRedis = integrationUrl ? describe : describe.skip;

function integrationClient(name: string): Redis {
  const client = new Redis(integrationUrl!, {
    connectionName: name,
    enableOfflineQueue: false,
    lazyConnect: true,
    maxRetriesPerRequest: 1,
  });
  client.on("error", () => undefined);
  return client;
}

async function closeClient(client: Redis | undefined): Promise<void> {
  if (!client) return;
  if (client.status === "wait" || client.status === "end") {
    client.disconnect();
    return;
  }
  await client.quit().catch(() => client.disconnect());
}

describeWithRedis("cross-replica Redis invalidation delivery", () => {
  const runId = randomUUID();
  const originalCachePrefix = process.env.REDIS_CACHE_PREFIX;
  const originalEventPrefix = process.env.REDIS_EVENT_PREFIX;
  const pageId = `integration-${runId}`;
  const topic = `page:${pageId}`;
  const cacheTag = pageCacheTag(pageId);
  const invalidatedAt = 1_725_000_000_000;

  let replicaA: Redis;
  let replicaBEvents: Redis;
  let replicaBCache: Redis;

  beforeAll(async () => {
    process.env.REDIS_CACHE_PREFIX = `buzz:test:${runId}:cache`;
    process.env.REDIS_EVENT_PREFIX = `buzz:test:${runId}:events`;

    replicaA = integrationClient(`buzz-sheet-test-a-${runId}`);
    replicaBEvents = integrationClient(`buzz-sheet-test-b-events-${runId}`);
    replicaBCache = integrationClient(`buzz-sheet-test-b-cache-${runId}`);
    await Promise.all([
      replicaA.connect(),
      replicaBEvents.connect(),
      replicaBCache.connect(),
    ]);
  });

  afterAll(async () => {
    if (replicaA?.status === "ready") {
      await replicaA.del(redisCacheTagStateKey());
    }
    await Promise.all([
      closeClient(replicaA),
      closeClient(replicaBEvents),
      closeClient(replicaBCache),
    ]);

    if (originalCachePrefix === undefined) delete process.env.REDIS_CACHE_PREFIX;
    else process.env.REDIS_CACHE_PREFIX = originalCachePrefix;
    if (originalEventPrefix === undefined) delete process.env.REDIS_EVENT_PREFIX;
    else process.env.REDIS_EVENT_PREFIX = originalEventPrefix;
  });

  it.each([
    ["catalog.updated", CATALOG_CACHE_TAG],
    ["glossary.updated", GLOSSARY_CACHE_TAG],
  ])("expires %s data across replicas", async (eventType, tag) => {
    await processOutboxEvent({
      topic: "admin", aggregateId: pageId, eventType,
      payload: { id: pageId, version: 43 },
    }, createRedisOutboxTransport(replicaA), invalidatedAt);
    expect(JSON.parse((await replicaBCache.hget(redisCacheTagStateKey(), tag))!))
      .toEqual({ expired: invalidatedAt });
  });

  it("shares tag state and publishes only the typed event envelope", async () => {
    const channel = redisEventChannel(topic);
    await replicaBEvents.subscribe(channel);

    const received = new Promise<string>((resolve, reject) => {
      const timeout = setTimeout(
        () => reject(new Error("Timed out waiting for the replica event.")),
        5_000,
      );
      replicaBEvents.on("message", (receivedChannel, value) => {
        if (receivedChannel !== channel) return;
        clearTimeout(timeout);
        resolve(value);
      });
    });

    const processed = await processOutboxEvent(
      {
        aggregateId: pageId,
        eventType: "page.updated",
        payload: {
          id: pageId,
          version: 42,
          privateContent: "must remain in PostgreSQL",
        },
        topic,
      },
      createRedisOutboxTransport(replicaA),
      invalidatedAt,
    );

    const rawEvent = await received;
    expect(parseInvalidationEvent(rawEvent)).toEqual(processed);
    expect(JSON.parse(rawEvent)).toEqual({
      type: "page.updated",
      id: pageId,
      version: 42,
    });

    const tagState = await replicaBCache.hget(
      redisCacheTagStateKey(),
      cacheTag,
    );
    expect(tagState && JSON.parse(tagState)).toEqual({
      expired: invalidatedAt,
    });
  });
});