const Redis = require('ioredis');

let redis = null;
let ttl = 30;

function init() {
  if (redis) {
    redis.disconnect();
  }

  const host = process.env.VALKEY_HOST || 'localhost';
  const port = parseInt(process.env.VALKEY_PORT) || 6379;
  const password = process.env.VALKEY_PASSWORD || undefined;
  const db = parseInt(process.env.VALKEY_DB) || 0;
  ttl = parseInt(process.env.VALKEY_TTL) || 30;

  try {
    redis = new Redis({
      host,
      port,
      password,
      db,
      lazyConnect: true,
      maxRetriesPerRequest: 1
    });

    redis.on('error', (err) => {
      // Fail silently after one retry, we just won't cache
      console.warn('[Cache] Valkey connection failed, caching disabled:', err.message);
    });
  } catch (err) {
    console.warn('[Cache] Valkey init failed:', err.message);
  }
}

init();

const cache = {
  init,
  async get(key) {
    if (!redis) return null;
    try {
      const data = await redis.get(key);
      return data ? JSON.parse(data) : null;
    } catch (e) {
      return null;
    }
  },

  async set(key, value, customTtl = ttl) {
    if (!redis) return;
    try {
      await redis.set(key, JSON.stringify(value), 'EX', customTtl);
    } catch (e) {
      // ignore
    }
  },

  async del(key) {
    if (!redis) return;
    try {
      await redis.del(key);
    } catch (e) {
      // ignore
    }
  },

  async checkHealth() {
    if (!redis) return { status: 'down', error: 'Valkey client not initialized' };
    try {
      const result = await redis.ping();
      if (result === 'PONG') return { status: 'up' };
      return { status: 'down', error: 'Invalid ping response' };
    } catch (e) {
      return { status: 'down', error: e.message };
    }
  }
};

module.exports = cache;