<?php
/**
 * Bulk Excel Import Endpoint
 * POST /v1/excel/import
 */

declare(strict_types=1);

use App\Core\Database;
use App\Core\Encryption;
use App\Middleware\AuthMiddleware;
use App\Middleware\QuotaMiddleware;
use PhpOffice\PhpSpreadsheet\IOFactory;

$decoded = AuthMiddleware::check();
$tenantId = $decoded['tenant_id'];

if (!isset($_FILES['file']) || $_FILES['file']['error'] !== UPLOAD_ERR_OK) {
    json_error('الملف مطلوب', 422);
}

$companyId = input('company_id');
if (!$companyId) {
    json_error('يجب تحديد الشركة', 422);
}

$file = $_FILES['file'];
$tmpPath = $file['tmp_name'];

try {
    $spreadsheet = IOFactory::load($tmpPath);
    $worksheet = $spreadsheet->getActiveSheet();
    $rows = $worksheet->toArray();

    if (count($rows) < 2) {
        json_error('الملف فارغ أو لا يحتوي على بيانات', 422);
    }

    $header = array_shift($rows);
    $mapping = mapColumns($header);

    $db = Database::getInstance();
    $db->beginTransaction();

    $importedCount = 0;
    $errors = [];

    foreach ($rows as $index => $row) {
        if (empty(array_filter($row))) continue; // Skip empty rows

        try {
            // Check quota for each invoice (preventive)
            QuotaMiddleware::checkInvoiceQuota($tenantId);

            $invoiceData = [
                'id' => Database::generateUuid(),
                'tenant_id' => $tenantId,
                'company_id' => $companyId,
                'invoice_number' => $row[$mapping['number']] ?? 'EXT-' . time() . '-' . $index,
                'invoice_date' => formatDate($row[$mapping['date']] ?? date('Y-m-d')),
                'customer_name' => Encryption::encrypt($row[$mapping['customer']] ?? 'عميل عام'),
                'grand_total' => (float)($row[$mapping['total']] ?? 0),
                'tax_amount' => (float)($row[$mapping['tax']] ?? 0),
                'status' => 'extracted', // Ready for review/approval
                'created_at' => date('Y-m-d H:i:s')
            ];

            $stmt = $db->prepare("
                INSERT INTO invoices (id, tenant_id, company_id, invoice_number, invoice_date, customer_name, grand_total, tax_amount, status, created_at)
                VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
            ");
            $stmt->execute(array_values($invoiceData));
            $importedCount++;

        } catch (\Exception $e) {
            $errors[] = "السطر " . ($index + 2) . ": " . $e->getMessage();
        }
    }

    $db->commit();

    json_success([
        'imported_count' => $importedCount,
        'errors' => $errors
    ], "تم استيراد $importedCount فاتورة بنجاح");

} catch (\Exception $e) {
    if (isset($db)) $db->rollBack();
    json_error('فشل معالجة ملف الاكسل: ' . $e->getMessage(), 500);
}

/**
 * Intelligent Column Mapping
 */
function mapColumns(array $header): array {
    $map = [
        'number' => 0,
        'date' => 1,
        'customer' => 2,
        'total' => 3,
        'tax' => 4
    ];

    foreach ($header as $i => $col) {
        $col = mb_strtolower(trim((string)$col));
        if (str_contains($col, 'رقم') || str_contains($col, 'number')) $map['number'] = $i;
        if (str_contains($col, 'تاريخ') || str_contains($col, 'date')) $map['date'] = $i;
        if (str_contains($col, 'عميل') || str_contains($col, 'customer') || str_contains($col, 'اسم')) $map['customer'] = $i;
        if (str_contains($col, 'اجمالي') || str_contains($col, 'total') || str_contains($col, 'المجموع')) $map['total'] = $i;
        if (str_contains($col, 'ضريبة') || str_contains($col, 'tax')) $map['tax'] = $i;
    }

    return $map;
}

function formatDate($val): string {
    if (is_numeric($val)) {
        return date('Y-m-d', \PhpOffice\PhpSpreadsheet\Shared\Date::excelToTimestamp($val));
    }
    $ts = strtotime((string)$val);
    return $ts ? date('Y-m-d', $ts) : date('Y-m-d');
}