<?php
    session_start();
    require '../../../assets/utils/db_auth.php';
    require '../../../assets/utils/classes/InvoiceManager.php';

    $inv = new InvoiceManager($pdo2, $company_id);
    $id  = (int)($data['invoice_id'] ?? 0);

    if ($id > 0) {
        $result = $inv->getInvoiceById($id);
        if (!$result) {
            http_response_code(404);
            $answer['message'] = 'Invoice not found.';
            exit(json_encode($answer));
        }
        $answer['output'] = $result;

        // Fetch linked credit notes for invoice detail page
        if ($result['doc_type'] === 'invoice') {
            $sth = $pdo2->prepare(
                "SELECT * FROM td_invoice
                 WHERE company_id    = :company_id
                   AND ref_invoice_id = :ref_id
                   AND doc_type      = 'credit_note'
                 ORDER BY id DESC"
            );
            $sth->execute([':company_id' => $company_id, ':ref_id' => $id]);
            $answer['credit_notes'] = $sth->fetchAll(PDO::FETCH_ASSOC);
        }
    } else {
        $order_id = (int)($data['order_id'] ?? 0);
        $doc_type = $data['doc_type'] ?? '';
        $answer['output'] = $inv->getInvoiceList($order_id, $doc_type);

        // For credit note tab — join ref invoice number
        if ($doc_type === 'credit_note') {
            $rows = $answer['output'];
            foreach ($rows as &$row) {
                if ((int)$row['ref_invoice_id'] > 0) {
                    $sth = $pdo2->prepare(
                        "SELECT invoice_number FROM td_invoice
                         WHERE id = :id AND company_id = :company_id"
                    );
                    $sth->execute([':id' => $row['ref_invoice_id'], ':company_id' => $company_id]);
                    $row['ref_invoice_number'] = $sth->fetchColumn() ?: '—';
                } else {
                    $row['ref_invoice_number'] = '—';
                }
            }
            unset($row);
            $answer['output'] = $rows;
        }
    }

    $answer['success'] = 1;
    exit(json_encode($answer));
?>