// controllers/admin/notificationSettings.controller.js

const CronNotificationSetting = require('../../models/notifications/cron_notification_setting.mdl');
const R = require('../../utils/response.util');
const logActivity = require('../../utils/logActivity.util');
const { CRON_PRESETS, CRON_PRESET_BY_EXPRESSION } = require('../../data/cronPresets.data');
const { rescheduleJob, getOrCreateSetting } = require('../../cron/cronRegistry.util');

// ─── Job registry — which cron scope owns each job (for defaults + labels) ────
const JOBS = {
  taskOverdue:       { schedule: '0 * * * *',   label: 'Task Alerts (Admin)', description: 'Automatically marks expired tasks as overdue or completed, and notifies admins.' },
  userNotifications: { schedule: '5 * * * *',   label: 'Task Alerts (Users)', description: 'Notifies affected users when their tasks are automatically marked overdue or completed.' },
  issueCertificates: { schedule: '0 * * * *',   label: 'Certificate Issued',          description: 'Notifies users when a course certificate is ready.' },
  expireUserTiers:   { schedule: '* * * * *',   label: 'Tier Expired',                description: 'Notifies users when their subscription tier expires.' },
};

// Jobs whose behavior can be tuned via target_status, and the values each accepts.
const TARGET_STATUS_OPTIONS = ['overdue', 'completed'];
const TARGET_STATUS_JOBS = ['taskOverdue'];

// ─── GET ──────────────────────────────────────────────────────────────────────

exports.getSettings = async (req, res) => {
  try {
    const rows = [];
    for (const [job_name, meta] of Object.entries(JOBS)) {
      const row = await getOrCreateSetting(job_name, meta.schedule);
      rows.push({
        job_name,
        enabled:  row.enabled,
        schedule: row.schedule,
        preset:   CRON_PRESET_BY_EXPRESSION[row.schedule] ?? null,
        target_status: TARGET_STATUS_JOBS.includes(job_name)
          ? (row.target_status ?? 'completed')
          : null,
        label:       meta.label,
        description: meta.description,
        updatedAt: row.updatedAt,
      });
    }

    return R.success(res, 'Notification settings retrieved.', rows);
  } catch (err) {
    console.error('[NOTIFICATION SETTINGS][GET]', err);
    return R.error(res, 'Could not retrieve notification settings.', 500);
  }
};

// ─── UPDATE ───────────────────────────────────────────────────────────────────

exports.updateSetting = async (req, res) => {
  try {
    const { jobName } = req.params;
    const { enabled, preset, target_status, updatedBy } = req.body;

    if (!JOBS[jobName]) return R.error(res, `Unknown job "${jobName}".`, 404);

    const row = await CronNotificationSetting.findOne({ where: { job_name: jobName } });
    if (!row) return R.error(res, 'Setting not found.', 404);

    if (enabled !== undefined) row.enabled = enabled === true || enabled === 'true';

    if (target_status !== undefined) {
      if (!TARGET_STATUS_JOBS.includes(jobName)) {
        return R.error(res, `"target_status" is not configurable for job "${jobName}".`, 400);
      }
      if (!TARGET_STATUS_OPTIONS.includes(target_status)) {
        return R.error(res, `Invalid target_status. Must be one of: ${TARGET_STATUS_OPTIONS.join(', ')}`, 400);
      }
      row.target_status = target_status;
    }

    if (preset !== undefined) {
      const schedule = CRON_PRESETS[preset];
      if (!schedule) return R.error(res, `Invalid preset. Must be one of: ${Object.keys(CRON_PRESETS).join(', ')}`, 400);
      row.schedule = schedule;

      try {
        rescheduleJob(jobName, schedule);
      } catch (err) {
        console.error('[NOTIFICATION SETTINGS][RESCHEDULE]', err);
        return R.error(res, `Saved, but failed to reschedule the live job: ${err.message}`, 500);
      }
    }

    row.updatedBy = updatedBy ?? null;
    await row.save();

    logActivity(req.user?.user_id, 'update_notification_setting', { entityType: 'cron_notification_setting', entityId: jobName, details: { enabled: row.enabled, schedule: row.schedule, target_status: row.target_status } });
    return R.success(res, 'Notification setting updated.', { data: row });
  } catch (err) {
    console.error('[NOTIFICATION SETTINGS][UPDATE]', err);
    return R.error(res, 'Internal server error.', 500);
  }
};