import { Queue } from 'bullmq';
import { getReminderDate } from '../reminders/reminderDate.js';
import { redisConnection } from './redisConnection.js';

export const weightReminderQueueName = 'weight-reminders';
export const weightReminderQueue = new Queue(weightReminderQueueName, {
  connection: redisConnection,
  defaultJobOptions: {
    attempts: 3,
    backoff: { type: 'exponential', delay: 60_000 },
    removeOnComplete: 100,
    removeOnFail: 1000,
  },
});

export const enqueueDailyWeightReminder = (now = new Date()) => {
  const runDate = getReminderDate(now);
  return weightReminderQueue.add('check-overdue-weights', { runDate }, {
    jobId: `weight-reminders-${runDate}`,
  });
};

export const startWeightReminderScheduler = async () => {
  // Remove the previous five-minute schedule during upgrades and when disabled.
  await weightReminderQueue.removeJobScheduler('weight-reminders');
  if (process.env.WEIGHT_REMINDERS_ENABLED === 'false') return () => {};
  await weightReminderQueue.setGlobalConcurrency(1);
  let lastRunDate = '';
  const runIfNeeded = async () => {
    const now = new Date();
    const runDate = getReminderDate(now);
    if (lastRunDate === runDate) return;
    await enqueueDailyWeightReminder(now);
    lastRunDate = runDate;
  };
  const check = () => {
    void runIfNeeded().catch(error => console.error('Weight reminder scheduler failed', error));
  };
  const startup = setTimeout(check, 15_000);
  const interval = setInterval(check, 60 * 60_000);
  return () => { clearTimeout(startup); clearInterval(interval); };
};