<?php
declare(strict_types=1);
namespace App\Services\JoFotara;

/**
 * UBLGeneratorService
 * 
 * Generates UBL 2.1 compliant XML using DOMDocument for precise namespace control.
 */
final class UBLGeneratorService
{
    public function generate(array $invoice, array $lines, array $company): string
    {
        $dom = new \DOMDocument('1.0', 'UTF-8');
        $dom->formatOutput = true;

        $root = $dom->createElementNS('urn:oasis:names:specification:ubl:schema:xsd:Invoice-2', 'Invoice');
        $root->setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:cac', 'urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2');
        $root->setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:cbc', 'urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2');
        $dom->appendChild($root);

        // 1. Basic Information
        $root->appendChild($dom->createElement('cbc:UBLVersionID', '2.1'));
        $root->appendChild($dom->createElement('cbc:CustomizationID', 'TRADACO-2.1'));
        $root->appendChild($dom->createElement('cbc:ProfileID', 'reporting:1.0'));
        $root->appendChild($dom->createElement('cbc:ID', $invoice['invoice_number']));
        $root->appendChild($dom->createElement('cbc:IssueDate', $invoice['invoice_date']));
        
        $typeCode = $dom->createElement('cbc:InvoiceTypeCode', $invoice['ubl_type_code'] ?? '388');
        $typeCode->setAttribute('name', $invoice['invoice_category'] ?? '01');
        $root->appendChild($typeCode);

        $root->appendChild($dom->createElement('cbc:DocumentCurrencyCode', 'JOD'));
        $root->appendChild($dom->createElement('cbc:TaxCurrencyCode', 'JOD'));

        // 2. AccountingSupplierParty
        $supplierParty = $dom->createElement('cac:AccountingSupplierParty');
        $party = $dom->createElement('cac:Party');
        
        $partyId = $dom->createElement('cac:PartyIdentification');
        $idNode = $dom->createElement('cbc:ID', $company['tax_identification_number']);
        $idNode->setAttribute('schemeID', 'TN');
        $partyId->appendChild($idNode);
        $party->appendChild($partyId);

        $partyName = $dom->createElement('cac:PartyName');
        $partyName->appendChild($dom->createElement('cbc:Name', $company['name']));
        $party->appendChild($partyName);

        $addr = $dom->createElement('cac:PostalAddress');
        $addr->appendChild($dom->createElement('cbc:CityName', $company['city'] ?? 'Amman'));
        $country = $dom->createElement('cac:Country');
        $country->appendChild($dom->createElement('cbc:IdentificationCode', 'JO'));
        $addr->appendChild($country);
        $party->appendChild($addr);

        $taxScheme = $dom->createElement('cac:PartyTaxScheme');
        $taxScheme->appendChild($dom->createElement('cbc:RegistrationName', $company['name']));
        $taxScheme->appendChild($dom->createElement('cbc:CompanyID', $company['tax_identification_number']));
        $ts = $dom->createElement('cac:TaxScheme');
        $ts->appendChild($dom->createElement('cbc:ID', 'VAT'));
        $taxScheme->appendChild($ts);
        $party->appendChild($taxScheme);

        $legalEntity = $dom->createElement('cac:PartyLegalEntity');
        $legalEntity->appendChild($dom->createElement('cbc:RegistrationName', $company['name']));
        $party->appendChild($legalEntity);

        $supplierParty->appendChild($party);
        $root->appendChild($supplierParty);

        // 3. AccountingCustomerParty
        $customerParty = $dom->createElement('cac:AccountingCustomerParty');
        $cParty = $dom->createElement('cac:Party');
        
        $cName = $dom->createElement('cac:PartyName');
        $cName->appendChild($dom->createElement('cbc:Name', $invoice['buyer_name'] ?? 'عميل عام'));
        $cParty->appendChild($cName);

        if (!empty($invoice['buyer_tin'])) {
            $cId = $dom->createElement('cac:PartyIdentification');
            $cidNode = $dom->createElement('cbc:ID', $invoice['buyer_tin']);
            $cidNode->setAttribute('schemeID', 'TN');
            $cId->appendChild($cidNode);
            $cParty->appendChild($cId);
        }

        $customerParty->appendChild($cParty);
        $root->appendChild($customerParty);

        // 4. PaymentMeans
        $paymentMeans = $dom->createElement('cac:PaymentMeans');
        $paymentMeans->appendChild($dom->createElement('cbc:PaymentMeansCode', $invoice['payment_method_code'] ?? '10'));
        $root->appendChild($paymentMeans);

        // 5. TaxTotal
        $taxTotal = $dom->createElement('cac:TaxTotal');
        $taxAmt = $dom->createElement('cbc:TaxAmount', number_format((float)$invoice['tax_amount'], 3, '.', ''));
        $taxAmt->setAttribute('currencyID', 'JOD');
        $taxTotal->appendChild($taxAmt);
        $root->appendChild($taxTotal);

        // 6. LegalMonetaryTotal
        $monetaryTotal = $dom->createElement('cac:LegalMonetaryTotal');
        $fields = [
            'LineExtensionAmount' => $invoice['subtotal'],
            'TaxExclusiveAmount' => $invoice['subtotal'],
            'TaxInclusiveAmount' => $invoice['grand_total'],
            'AllowanceTotalAmount' => $invoice['discount_total'] ?? 0,
            'PayableAmount' => $invoice['grand_total']
        ];
        foreach ($fields as $field => $val) {
            $node = $dom->createElement('cbc:' . $field, number_format((float)$val, 3, '.', ''));
            $node->setAttribute('currencyID', 'JOD');
            $monetaryTotal->appendChild($node);
        }
        $root->appendChild($monetaryTotal);

        // 7. Invoice Lines
        foreach ($lines as $line) {
            $iLine = $dom->createElement('cac:InvoiceLine');
            $iLine->appendChild($dom->createElement('cbc:ID', (string)$line['line_number']));
            
            $qty = $dom->createElement('cbc:InvoicedQuantity', number_format((float)$line['quantity'], 3, '.', ''));
            $qty->setAttribute('unitCode', 'PCE');
            $iLine->appendChild($qty);
            
            $lineExt = $dom->createElement('cbc:LineExtensionAmount', number_format((float)$line['line_total'], 3, '.', ''));
            $lineExt->setAttribute('currencyID', 'JOD');
            $iLine->appendChild($lineExt);

            $item = $dom->createElement('cac:Item');
            $item->appendChild($dom->createElement('cbc:Description', $line['description']));
            $iLine->appendChild($item);

            $price = $dom->createElement('cac:Price');
            $pAmt = $dom->createElement('cbc:PriceAmount', number_format((float)$line['unit_price'], 3, '.', ''));
            $pAmt->setAttribute('currencyID', 'JOD');
            $price->appendChild($pAmt);
            $iLine->appendChild($price);

            $root->appendChild($iLine);
        }

        return $dom->saveXML();
    }
}