/***********************************************************************************************************************************************************************
 * File Name    : task_overdue.cron.js
 * Type         : Cron Job
 * Description  : Flips Task.status to a configurable target status — 'overdue'
 *                (default before Jul 2026) or 'completed' (current default) —
 *                once its deadline has passed, provided it isn't already
 *                'completed' or 'overdue'. The target status is an admin-
 *                configurable setting (cron_notification_settings.target_status
 *                for job_name 'taskOverdue'; NULL is treated as 'completed').
 *                Purely an admin-facing lifecycle label — does NOT touch
 *                TaskCompletion/TaskLinkVisit/TaskProgress, does NOT affect
 *                per-user completion signals or client-side Ongoing/Done/
 *                Overdue bucketing, and does NOT block late submissions.
 *
 *                Every task this job touches also gets auto_marked_at set to
 *                the current time — this is the ONLY writer of that column,
 *                so downstream consumers (e.g. cron/jobs/user_notifications.cron.js)
 *                can distinguish "the system just did this" from a user's own
 *                legitimate completion. A task already sitting in 'overdue' or
 *                'completed' is never reclaimed by this sweep even if the
 *                target status changes later — this job only ever moves tasks
 *                OUT of 'pending'/'in_progress', never between the two terminal
 *                states.
 *
 *                Safety pattern:
 *                  - Task.update is the primary operation and must always succeed.
 *                  - AdminNotification.create is secondary — wrapped in its own
 *                    try/catch so a notification failure never rolls back or
 *                    suppresses the status flip. If it fails once, the next
 *                    hourly run will insert its own summary for that batch.
 *
 * Schedule     : Every hour, on the hour ("0 * * * *"). Registered by
 *                cron/admin.cron.js, not scheduled here directly.
 *
 * Author: Kenneth Obsequio (@lash0000)
 * Date Created: Jun. 17, 2026
 * Modified    : Jun. 19, 2026
 ***********************************************************************************************************************************************************************/
const { Op } = require('sequelize');
const { Task } = require('../../models/task/task.mdl');
const AdminNotification = require('../../models/notifications/admin_notification.mdl');
const CronNotificationSetting = require('../../models/notifications/cron_notification_setting.mdl');
const { NOTIFICATION_REGISTRY } = require('../../data/notifications.data');

// ─── The actual sweep ────────────────────────────────────────────────────────
async function run() {
    // ── 0. Load configured target status (defaults to 'completed') ───────────
    let settings = null;
    let targetStatus = 'completed';
    try {
        settings = await CronNotificationSetting.findOne({ where: { job_name: 'taskOverdue' } });
        if (settings?.target_status === 'overdue' || settings?.target_status === 'completed') {
            targetStatus = settings.target_status;
        }
    } catch (err) {
        console.error('[CRON][TASK OVERDUE] Failed to load target_status setting, defaulting to "completed":', err);
    }

    // ── 1. Primary: flip task statuses ───────────────────────────────────────
    let affectedCount = 0;

    try {
        [affectedCount] = await Task.update(
            { status: targetStatus, auto_marked_at: new Date() },
            {
                where: {
                    deadline: { [Op.lt]: new Date() },
                    status:   { [Op.notIn]: ['completed', 'overdue'] },
                },
            }
        );
    } catch (err) {
        console.error('[CRON][TASK OVERDUE] Failed to update task statuses:', err);
        return;
    }

    if (affectedCount === 0) return;

    console.log(`[CRON][TASK OVERDUE] Marked ${affectedCount} task(s) as ${targetStatus}.`);

    // ── 2. Secondary: admin notification — isolated, never blocks step 1 ─────
    // Skippable via /admin/notifications/settings — the status flip above always happens either way.
    try {
        if (settings && !settings.enabled) return;

        await AdminNotification.create(
            NOTIFICATION_REGISTRY.task_overdue.build({ count: affectedCount, targetStatus })
        );
    } catch (err) {
        console.error('[CRON][TASK OVERDUE] Failed to insert admin notification:', err);
    }
}

module.exports = {
    name:     'taskOverdue',
    schedule: '0 * * * *',
    run,
};