<?php
// Admin/fuel/drawdowns.php — حركة القسائم وملخّص الائتمان
// POST (اختياري): station_id, status, driver_id, limit
//
// ‏الشاشة التي تُجيب: كم أقرضنا؟ كم استُرد؟ وأي محطة تعمل؟

require_once __DIR__ . '/../../connect.php';

if ($role !== 'admin' && $role !== 'super_admin') {
    jsonError('Unauthorized: Admin access required', 403);
}

$stationId = (int) (filterRequest('station_id', 'int') ?: 0);
$status    = filterRequest('status');
$driverId  = filterRequest('driver_id');
$limit     = (int) (filterRequest('limit', 'int') ?: 100);
$limit     = max(1, min($limit, 500));

$where  = [];
$params = [];

if ($stationId > 0) {
    $where[] = 'v.station_id = ?';
    $params[] = $stationId;
}
if (!empty($status)) {
    $where[] = 'v.status = ?';
    $params[] = $status;
}
if (!empty($driverId)) {
    $where[] = 'v.driver_id = ?';
    $params[] = $driverId;
}

$clause = $where ? 'WHERE ' . implode(' AND ', $where) : '';

try {
    $st = $con->prepare("
        SELECT v.id, v.driver_id, v.code, v.amount_authorized, v.amount_redeemed,
               v.currency, v.status, v.expires_at, v.redeemed_at, v.created_at,
               s.name_ar AS station_name
        FROM fuel_vouchers v
        LEFT JOIN fuel_stations s ON s.id = v.station_id
        $clause
        ORDER BY v.id DESC
        LIMIT $limit
    ");
    $st->execute($params);
    $rows = $st->fetchAll(PDO::FETCH_ASSOC);

    // ‏الملخّص على كامل المنتج لا على الصفحة المعروضة: رقمٌ يتغيّر بتغيّر
    // ‏الفلتر يُقرأ كأنه حقيقة عن المنصة وهو ليس كذلك.
    $summary = $con->query("
        SELECT
          COALESCE(SUM(amount), 0)           AS lent_total,
          COALESCE(SUM(amount_collected), 0) AS collected_total,
          COALESCE(SUM(amount_remaining), 0) AS outstanding_total,
          COUNT(DISTINCT driver_id)          AS drivers_count
        FROM obligation_ledger
        WHERE product_code = 'fuel_wallet'
    ")->fetch(PDO::FETCH_ASSOC) ?: [];
} catch (PDOException $e) {
    error_log('[admin/fuel/drawdowns] ' . $e->getMessage());
    jsonError('Server error', 500);
}

$vouchers = array_map(static fn(array $r): array => [
    'id'                => (int) $r['id'],
    'driver_id'         => $r['driver_id'],
    'code'              => $r['code'],
    'amount_authorized' => (float) $r['amount_authorized'],
    'amount_redeemed'   => (float) $r['amount_redeemed'],
    'currency'          => $r['currency'],
    'status'            => $r['status'],
    'station'           => $r['station_name'],
    'expires_at'        => $r['expires_at'],
    'redeemed_at'       => $r['redeemed_at'],
    'created_at'        => $r['created_at'],
], $rows);

jsonSuccess([
    'vouchers' => $vouchers,
    'summary'  => [
        'lent_total'        => (float) ($summary['lent_total'] ?? 0),
        'collected_total'   => (float) ($summary['collected_total'] ?? 0),
        'outstanding_total' => (float) ($summary['outstanding_total'] ?? 0),
        'drivers_count'     => (int) ($summary['drivers_count'] ?? 0),
    ],
], 'success');