<?php
require_once __DIR__ . '/../api/helpers.php';
// No runAuth() — cron/public endpoint

/**
 * Expire stale chats (older than 20 minutes with no recent activity).
 * Called every minute by cron.
 */

try {
    $staleChats = queryTimed("
        SELECT t.ID, t.CreatedOn,
               (SELECT MAX(cm.CreatedOn) FROM ChatMessages cm WHERE cm.TaskID = t.ID) AS LastMessageOn
        FROM Tasks t
        WHERE t.TaskTypeID = 2
          AND t.CompletedOn IS NULL
          AND t.CreatedOn < DATE_SUB(NOW(), INTERVAL 20 MINUTE)
    ");

    $expiredCount = 0;
    $expiredIds = [];

    foreach ($staleChats as $chat) {
        $shouldExpire = false;

        if (empty($chat['LastMessageOn'])) {
            $shouldExpire = true;
        } else {
            $lastMsg = new DateTime($chat['LastMessageOn'], new DateTimeZone('UTC'));
            $now = new DateTime('now', new DateTimeZone('UTC'));
            $diffMinutes = ($now->getTimestamp() - $lastMsg->getTimestamp()) / 60;
            if ($diffMinutes > 20) {
                $shouldExpire = true;
            }
        }

        if ($shouldExpire) {
            queryTimed("UPDATE Tasks SET CompletedOn = NOW() WHERE ID = ?", [$chat['ID']]);
            $expiredCount++;
            $expiredIds[] = (int) $chat['ID'];
        }
    }

    jsonResponse([
        'OK'               => true,
        'MESSAGE'          => "Expired {$expiredCount} stale chat(s)",
        'EXPIRED_TASK_IDS' => $expiredIds,
        'CHECKED_COUNT'    => count($staleChats),
    ]);

} catch (Exception $e) {
    jsonResponse(['OK' => false, 'ERROR' => 'server_error', 'MESSAGE' => $e->getMessage()]);
}