<?php

if (!defined('ABSPATH')) {
    exit;
}

// «Send queue» on the plugin's page: the sync's jobs in Action Scheduler, one
// line each saying which products, why they wait and when they go. It is read
// only when an admin opens that page or presses its refresh, from the rows
// Action Scheduler keeps anyway; a checkout or a product save does nothing
// more for it.

add_action('wp_ajax_rayachat_sync_queue', 'rayachat_ajax_sync_queue');
add_action('wp_ajax_rayachat_sync_queue_run', 'rayachat_ajax_sync_queue_run');

// Lines drawn; the rest are counted.
define('RAYACHAT_QUEUE_SHOWN', 8);

/**
 * The jobs in line, running ones first, then by when they go, with the
 * products each kind holds. Read once per page.
 */
function rayachat_sync_queue()
{
    static $queue = null;
    if ($queue !== null) {
        return $queue;
    }
    $queue = array('items' => array(), 'kinds' => array(), 'products' => 0, 'capped' => false);
    if (!function_exists('as_get_scheduled_actions')) {
        return $queue;
    }
    $reads = array(ActionScheduler_Store::STATUS_RUNNING => 20, ActionScheduler_Store::STATUS_PENDING => 200);
    foreach ($reads as $status => $limit) {
        $actions = as_get_scheduled_actions(array(
            'group'    => RAYACHAT_SYNC_GROUP,
            'status'   => $status,
            'per_page' => $limit,
            'orderby'  => 'date',
            'order'    => 'ASC',
        ));
        foreach ($actions as $id => $action) {
            $item = rayachat_queue_item($action, $status === ActionScheduler_Store::STATUS_RUNNING);
            if (!$item) {
                continue;
            }
            $item['id'] = (int) $id;
            $queue['items'][] = $item;
            $group = in_array($item['kind'], array('change', 'bulk'), true) ? 'change' : $item['kind'];
            $count = $item['kind'] === 'full' ? 1 : count($item['ids']);
            $queue['kinds'][$group] = ($queue['kinds'][$group] ?? 0) + $count;
            if ($item['kind'] !== 'image' && $item['kind'] !== 'full') {
                $queue['products'] += $count;
            }
        }
        $queue['capped'] = $queue['capped'] || count($actions) >= $limit;
    }

    return $queue;
}

/**
 * One job as the page describes it, or null for the daily check, which the
 * card above shows as its own date. 'change' is a single product waiting out
 * the delay; whether the owner's edit or a sale started it is settled only for
 * the lines drawn (rayachat_queue_settle).
 */
function rayachat_queue_item($action, $running)
{
    $args = $action->get_args();
    $schedule = $action->get_schedule();
    $date = $schedule ? $schedule->get_date() : null;
    // An async job has no date: it runs the next time the queue does.
    $item = array('at' => $date ? $date->getTimestamp() : 0, 'running' => $running, 'ids' => array(), 'attempt' => 0);

    switch ($action->get_hook()) {
        case 'rayachat_sync_products':
            $item['ids'] = isset($args[0]) && is_array($args[0]) ? array_map('intval', $args[0]) : array();
            $item['attempt'] = isset($args[1]) ? (int) $args[1] : 0;
            if ($item['attempt'] > 0) {
                $item['kind'] = 'retry';
            } elseif (!$date) {
                $item['kind'] = 'later';
            } else {
                $item['kind'] = count($item['ids']) > 1 ? 'bulk' : 'change';
            }
            return $item['ids'] ? $item : null;
        case 'rayachat_sync_image':
            $item['kind'] = 'image';
            $item['ids'] = array((int) ($args[0] ?? 0));
            return $item;
        case 'rayachat_full_sync':
            $item['kind'] = 'full';
            $item['phase'] = (string) ($args[0] ?? 'products');
            $item['page'] = max(1, (int) ($args[1] ?? 1));
            $item['attempt'] = (int) ($args[2] ?? 0);
            return $item;
    }

    return null;
}

/**
 * Loads what the drawn lines name in two reads, the products' posts and the
 * edit notes, and tells an edit from a sale: an edit's wait keeps a note
 * naming it (rayachat_queue_changes), a sale's has none.
 */
function rayachat_queue_settle(array $items)
{
    $ids = array();
    $notes = array();
    foreach ($items as $item) {
        $ids = array_merge($ids, array_slice($item['ids'], 0, 1));
        if ($item['kind'] === 'change') {
            $notes[] = '_transient_rayachat_wait_' . $item['ids'][0];
            $notes[] = '_transient_timeout_rayachat_wait_' . $item['ids'][0];
        }
    }
    if ($ids && function_exists('_prime_post_caches')) {
        _prime_post_caches(array_unique($ids), false, false);
    }
    if ($notes && !wp_using_ext_object_cache() && function_exists('wp_prime_option_caches')) {
        wp_prime_option_caches($notes);
    }

    foreach ($items as &$item) {
        // An async job's schedule has no date, but its row keeps when it was
        // queued, and it was due from then.
        if (!$item['at'] && !$item['running']) {
            try {
                $item['at'] = ActionScheduler::store()->get_date($item['id'])->getTimestamp();
            } catch (Exception $e) {
                $item['at'] = 0;
            }
        }
        // Action Scheduler runs one batch at a time for every plugin on the
        // site, and only when a request starts it, so a job can sit past its
        // time while a cache preload or another plugin's jobs go first.
        $item['late'] = !$item['running'] && $item['at'] && time() - $item['at'] >= MINUTE_IN_SECONDS ? time() - $item['at'] : 0;
        if ($item['kind'] !== 'change') {
            continue;
        }
        $note = get_transient('rayachat_wait_' . $item['ids'][0]);
        $edit = isset($note['wait'], $note['first']) && (int) $note['wait'] === $item['id'];
        $item['kind'] = $edit ? 'edit' : 'sale';
        if ($edit) {
            $item['cap'] = (int) $note['first'] + 2 * rayachat_sync_delay() * MINUTE_IN_SECONDS;
        }
    }
    unset($item);

    return $items;
}

// The products a line is about: a name and its edit link, or the first name and how many more.
function rayachat_queue_subject(array $item)
{
    if ($item['kind'] === 'full') {
        return esc_html__('Full sync', 'raya-ai');
    }
    $id = $item['ids'][0];
    $title = get_post($id) ? get_the_title($id) : '';
    /* translators: %s: the product's ID. */
    $name = $title !== '' ? $title : sprintf(__('Product #%s', 'raya-ai'), rayachat_digits($id));
    $link = get_post($id) ? get_edit_post_link($id) : '';
    $html = $link ? sprintf('<a href="%s">%s</a>', esc_url($link), esc_html($name)) : esc_html($name);
    $more = count($item['ids']) - 1;
    if ($more < 1) {
        return $html;
    }

    return sprintf(
        /* translators: 1: a product's name, 2: how many other products. */
        esc_html(_n('%1$s and %2$s more product', '%1$s and %2$s more products', $more, 'raya-ai')),
        $html,
        esc_html(rayachat_number($more))
    );
}

// Why a line waits, in a sentence. A single product no longer published is about to leave the chatbot.
function rayachat_queue_reason(array $item)
{
    if (count($item['ids']) === 1 && $item['kind'] !== 'image') {
        $status = get_post_status($item['ids'][0]);
        if ($status === false) {
            return __('Deleted from the store, so it will be removed from the chatbot.', 'raya-ai');
        }
        if ($status === 'trash') {
            return __('In the trash, so it will be removed from the chatbot. Restore it before then to keep it.', 'raya-ai');
        }
        if ($status !== 'publish') {
            return __('No longer published, so it will be removed from the chatbot.', 'raya-ai');
        }
    }

    switch ($item['kind']) {
        case 'edit':
            return sprintf(
                /* translators: %s: a time of day. */
                __('Your edit. Each new edit starts the wait again, up to %s at the latest.', 'raya-ai'),
                rayachat_digits(wp_date(get_option('time_format'), $item['cap']))
            );
        case 'sale':
            return __('A sale or stock update. It starts no wait over, and however many sales, it is sent once.', 'raya-ai');
        case 'bulk':
            return __('A bulk edit or stock import, sent together after the wait.', 'raya-ai');
        case 'retry':
            /* translators: 1: this retry's number, 2: how many retries there are in all. */
            return sprintf(__('Did not get through last time. Retry %1$s of %2$s, each later than the last.', 'raya-ai'), rayachat_number($item['attempt']), rayachat_number(RAYACHAT_RETRY_LIMIT));
        case 'later':
            return __('Left over from a full sync that ran out of time; sent in the background.', 'raya-ai');
        case 'image':
            return __('The main picture, uploaded on its own after the product’s details.', 'raya-ai');
    }

    $step = $item['phase'] === 'reconcile'
        ? __('Removing the products the store no longer shows.', 'raya-ai')
        /* translators: 1: first product number, 2: last product number. */
        : sprintf(__('Checking products %1$s to %2$s against the chatbot.', 'raya-ai'), rayachat_number(($item['page'] - 1) * RAYACHAT_CHECK_PAGE + 1), rayachat_number($item['page'] * RAYACHAT_CHECK_PAGE));

    return $item['attempt'] > 0 ? $step . ' ' . __('Trying again: Rayachat could not be reached.', 'raya-ai') : $step;
}

function rayachat_queue_when(array $item)
{
    if ($item['running']) {
        return __('Sending now', 'raya-ai');
    }
    if ($item['late'] >= HOUR_IN_SECONDS) {
        $hours = (int) floor($item['late'] / HOUR_IN_SECONDS);
        /* translators: %s: number of hours. */
        return sprintf(_n('Waiting for WordPress, %s hour late', 'Waiting for WordPress, %s hours late', $hours, 'raya-ai'), rayachat_number($hours));
    }
    if ($item['late']) {
        $minutes = (int) floor($item['late'] / MINUTE_IN_SECONDS);
        /* translators: %s: number of minutes. */
        return sprintf(_n('Waiting for WordPress, %s minute late', 'Waiting for WordPress, %s minutes late', $minutes, 'raya-ai'), rayachat_number($minutes));
    }
    $left = $item['at'] - time();
    if ($left < 60) {
        return __('Any moment', 'raya-ai');
    }
    if ($left < HOUR_IN_SECONDS) {
        $minutes = (int) ceil($left / MINUTE_IN_SECONDS);
        /* translators: %s: number of minutes. */
        return sprintf(_n('in %s minute', 'in %s minutes', $minutes, 'raya-ai'), rayachat_number($minutes));
    }
    $hours = (int) round($left / HOUR_IN_SECONDS);
    /* translators: %s: number of hours. */
    return sprintf(_n('in %s hour', 'in %s hours', $hours, 'raya-ai'), rayachat_number($hours));
}

function rayachat_queue_icon(array $item)
{
    if (count($item['ids']) === 1 && $item['kind'] !== 'image' && get_post_status($item['ids'][0]) !== 'publish') {
        return array('remove', 'trash');
    }
    $icons = array(
        'edit'   => 'edit',
        'sale'   => 'cart',
        'bulk'   => 'screenoptions',
        'retry'  => 'controls-repeat',
        'later'  => 'update',
        'image'  => 'format-image',
        'full'   => 'database',
    );

    return array($item['kind'], $icons[$item['kind']] ?? 'clock');
}

function rayachat_render_sync_queue()
{
    $queue = rayachat_sync_queue();
    $items = rayachat_queue_settle(array_slice($queue['items'], 0, RAYACHAT_QUEUE_SHOWN));
    $more = count($queue['items']) - count($items);
    $chips = array(
        /* translators: %s: number of products. */
        'change' => _n('%s product change', '%s product changes', $queue['kinds']['change'] ?? 0, 'raya-ai'),
        /* translators: %s: number of products. */
        'retry'  => _n('%s to retry', '%s to retry', $queue['kinds']['retry'] ?? 0, 'raya-ai'),
        /* translators: %s: number of products. */
        'later'  => _n('%s from a full sync', '%s from a full sync', $queue['kinds']['later'] ?? 0, 'raya-ai'),
        /* translators: %s: number of pictures. */
        'image'  => _n('%s picture', '%s pictures', $queue['kinds']['image'] ?? 0, 'raya-ai'),
        'full'   => __('Full sync under way', 'raya-ai'),
    );
    $jobs = count($queue['items']);
    ?>
    <div class="rc-queue" id="rayachat-sync-queue">
        <div class="rc-queue__head">
            <p class="rc-queue__total">
                <?php
                echo $jobs
                    /* translators: %s: number of jobs. */
                    ? esc_html(sprintf(_n('%s job in line', '%s jobs in line', $jobs, 'raya-ai'), rayachat_number($jobs) . ($queue['capped'] ? '+' : '')))
                    : esc_html__('The queue is empty', 'raya-ai');
                ?>
            </p>
            <button type="button" class="button-link rc-queue__refresh" data-rayachat-queue-refresh>
                <span class="dashicons dashicons-update" aria-hidden="true"></span>
                <?php esc_html_e('Refresh', 'raya-ai'); ?>
            </button>
        </div>
        <?php if (!$jobs) : ?>
            <p class="rc-queue__empty">
                <span class="dashicons dashicons-yes-alt" aria-hidden="true"></span>
                <?php esc_html_e('Nothing waiting: every change has reached the chatbot.', 'raya-ai'); ?>
            </p>
        <?php else : ?>
            <ul class="rc-queue__chips">
                <?php foreach ($chips as $kind => $label) : ?>
                    <?php if (!empty($queue['kinds'][$kind])) : ?>
                        <li class="rc-queue__chip rc-queue__chip--<?php echo esc_attr($kind); ?>"><?php echo esc_html(sprintf($label, rayachat_number($queue['kinds'][$kind]))); ?></li>
                    <?php endif; ?>
                <?php endforeach; ?>
            </ul>
            <ol class="rc-queue__list">
                <?php foreach ($items as $item) : ?>
                    <?php
                    list($tone, $icon) = rayachat_queue_icon($item);
                    ?>
                    <li class="rc-queue__item rc-queue__item--<?php echo esc_attr($tone); ?><?php echo $item['late'] ? ' rc-queue__item--late' : ''; ?>">
                        <span class="rc-queue__icon dashicons dashicons-<?php echo esc_attr($icon); ?>" aria-hidden="true"></span>
                        <span class="rc-queue__title"><?php echo wp_kses(rayachat_queue_subject($item), array('a' => array('href' => true))); ?></span>
                        <span
                            class="rc-queue__when<?php echo $item['running'] ? ' rc-queue__when--now' : ($item['late'] ? ' rc-queue__when--late' : ''); ?>"
                            <?php echo $item['at'] ? 'title="' . esc_attr(rayachat_sync_date($item['at'])) . '"' : ''; ?>
                        ><?php echo esc_html(rayachat_queue_when($item)); ?></span>
                        <span class="rc-queue__why"><?php echo esc_html(rayachat_queue_reason($item)); ?></span>
                        <?php if ($item['late']) : ?>
                            <button type="button" class="button button-small rc-queue__run" data-rayachat-queue-run="<?php echo esc_attr($item['id']); ?>"><?php esc_html_e('Send now', 'raya-ai'); ?></button>
                        <?php endif; ?>
                    </li>
                <?php endforeach; ?>
            </ol>
            <?php if (array_filter(array_column($items, 'late'))) : ?>
                <p class="rc-queue__late"><?php esc_html_e('WordPress runs the scheduled jobs of every plugin in a single line, and only when someone opens the site or its admin, so a job can wait past its time. “Send now” sends it at once.', 'raya-ai'); ?></p>
            <?php endif; ?>
            <?php if ($more > 0) : ?>
                <p class="rc-queue__more">
                    <?php
                    /* translators: %s: number of jobs. */
                    echo esc_html(sprintf(_n('and %s more job in line', 'and %s more jobs in line', $more, 'raya-ai'), rayachat_number($more) . ($queue['capped'] ? '+' : '')));
                    ?>
                </p>
            <?php endif; ?>
        <?php endif; ?>
    </div>
    <?php
}

function rayachat_ajax_sync_queue()
{
    check_ajax_referer('rayachat_full_sync');
    if (!current_user_can('manage_options')) {
        wp_send_json_error(null, 403);
    }
    ob_start();
    rayachat_render_sync_queue();
    wp_send_json_success(ob_get_clean());
}

// «Send now» on a line past its time: runs that job in this request, as the
// «Run» link under WooCommerce's Scheduled Actions does, then draws the queue again.
function rayachat_ajax_sync_queue_run()
{
    check_ajax_referer('rayachat_full_sync');
    if (!current_user_can('manage_options')) {
        wp_send_json_error(null, 403);
    }
    $id = isset($_POST['id']) ? absint(wp_unslash($_POST['id'])) : 0;
    if ($id && rayachat_queue_runnable($id)) {
        ActionScheduler::runner()->process_action($id, 'Rayachat send queue');
    }
    ob_start();
    rayachat_render_sync_queue();
    wp_send_json_success(ob_get_clean());
}

/**
 * Only the sync's own jobs, still pending and past their time: sending an
 * edit early would skip the wait that lets the owner take it back. One a queue
 * runner has already claimed is about to run, and running it here too would
 * send it twice.
 */
function rayachat_queue_runnable($id)
{
    if (!class_exists('ActionScheduler')) {
        return false;
    }
    $store = ActionScheduler::store();
    try {
        if ($store->get_status($id) !== ActionScheduler_Store::STATUS_PENDING || $store->get_date($id)->getTimestamp() > time()) {
            return false;
        }
    } catch (Exception $e) {
        return false;
    }
    $action = $store->fetch_action($id);
    if ($action->get_group() !== RAYACHAT_SYNC_GROUP || !in_array($action->get_hook(), array('rayachat_sync_products', 'rayachat_sync_image', 'rayachat_full_sync'), true)) {
        return false;
    }

    return !method_exists($store, 'get_claim_id') || !$store->get_claim_id($id);
}