<?php
declare(strict_types=1);

require_once __DIR__ . '/db.php';

if ($_SERVER['REQUEST_METHOD'] !== 'GET') {
    error_out('Method not allowed', 405);
}

// ─── GET /api/delivery-log.php ────────────────────────────────────────────────
// Optional query params:
//   ?page=N   (default 1, 50 rows per page)

try {
    $db = db();

    // Aggregate stats — sandbox sends (is_sandbox=1) are excluded so they don't
    // inflate cost calculations or success rate on the dashboard.
    $stats = $db->query(
        "SELECT
            SUM(status IN ('sent','delivered') AND is_sandbox = 0)  AS total_sent,
            SUM(status = 'failed'              AND is_sandbox = 0)  AS total_failed
         FROM delivery_log"
    )->fetch();

    $total_attempts = (int) $stats['total_sent'] + (int) $stats['total_failed'];
    $stats['success_rate'] = $total_attempts > 0
        ? round(((int) $stats['total_sent'] / $total_attempts) * 100, 1)
        : 0.0;

    // Paginated log entries — pass ?all=1 to skip pagination (used by DataTables)
    $fetchAll = isset($_GET['all']) && $_GET['all'] === '1';
    $perPage  = 50;
    $page     = max(1, (int) ($_GET['page'] ?? 1));
    $offset   = ($page - 1) * $perPage;

    $limitClause = $fetchAll ? '' : "LIMIT $perPage OFFSET $offset";

    // $perPage and $offset are cast ints — no injection risk from interpolation
    $entries = $db->query(
        "SELECT dl.id, dl.mobile_number, dl.status, dl.sent_at, dl.delivered_at, dl.error_message,
                CONCAT(a.first_name, ' ', a.last_name)              AS attendee_name,
                COALESCE(t.name, 'Custom message')                   AS template_name,
                COALESCE(sj.custom_body, t.body)                     AS message_body,
                sj.id                                                AS job_id
         FROM delivery_log dl
         LEFT JOIN attendees a        ON a.id  = dl.attendee_id
         LEFT JOIN send_jobs sj       ON sj.id = dl.send_job_id
         LEFT JOIN sms_templates t    ON t.id  = sj.template_id
         ORDER BY dl.sent_at DESC
         $limitClause"
    )->fetchAll();

    $total = (int) $db->query('SELECT COUNT(*) FROM delivery_log')->fetchColumn();

    json_out([
        'stats'    => $stats,
        'entries'  => $entries,
        'total'    => $total,
        'page'     => $fetchAll ? 1 : $page,
        'per_page' => $fetchAll ? $total : $perPage,
        'pages'    => $fetchAll ? 1 : (int) ceil($total / $perPage),
    ]);

} catch (PDOException $e) {
    error_out('Database error: ' . $e->getMessage(), 500);
}