How to optimize the code, make it more professional?

Question

PHP

$tableHTML = '<div class="scaleInTop">' . "\n";
$tableHTML .= '<div class="borderedBlock">' . "\n";
$tableHTML .= '<table class="table table-bordered align-middle">' . "\n";
$tableHTML .= '        <tr class="tableGreen text-center">' . "\n";
$tableHTML .= '            <td colspan="3">Карточка торговой точки</td>' . "\n";
$tableHTML .= '            <td>Дата создания: ' . date('d.m.Y', strtotime($callCompanyData['result']['DATE_CREATE'])) . '</td>' . "\n";
$tableHTML .= '            <td>Дата изменения: ' . date('d.m.Y H:i:s', strtotime($callCompanyData['result']['DATE_CREATE'])) . '</td>' . "\n";
$tableHTML .= '        </tr>' . "\n";
$tableHTML .= '        <tr class="tableGrey">' . "\n";
$tableHTML .= '            <td>Наименование Компании</td>' . "\n";
$tableHTML .= '            <td colspan="4">' . (!empty($callCompanyData['result']['TITLE']) ? $callCompanyData['result']['TITLE'] : ' ') . '</td>' . "\n";
$tableHTML .= '        </tr>' . "\n";
$tableHTML .= '        <tr class="tableGrey">' . "\n";
$tableHTML .= '            <td>Торговая точка</td>' . "\n";
$tableHTML .= '            <td colspan="4">' . (!empty($callCompanyData['result']['UF_CRM_1587463057321']) ? $callCompanyData['result']['UF_CRM_1587463057321'] : ' ') . '</td>' . "\n";
$tableHTML .= '        </tr>' . "\n";
$tableHTML .= '        <tr class="tableGrey">' . "\n";
$tableHTML .= '            <td>Телефон</td>' . "\n";
$tableHTML .= '            <td colspan="2">' . (!empty($collectedPhones) ? $collectedPhones : ' ') . '</td>' . "\n";
$tableHTML .= '            <td>E-Mail</td>' . "\n";
$tableHTML .= '            <td colspan="2">' . (!empty($collectedEmails) === true ? $collectedEmails : ' ') . '</td>' . "\n";
$tableHTML .= '        </tr>' . "\n";
$tableHTML .= '        <tr class="tableGrey">' . "\n";
$tableHTML .= '            <td>Фактический адрес</td>' . "\n";
$tableHTML .= '            <td colspan="4">' . (!empty($callCompanyData['result']['UF_CRM_1587463057321']) ? $callCompanyData['result']['UF_CRM_1587463057321'] : ' ') . '</td>' . "\n";
$tableHTML .= '        </tr>' . "\n";
$tableHTML .= '</table>' . "\n";
$tableHTML .= '</div>' . "\n";

Answer 1

All these punctuation marks don't dazzle in your eyes
1. Do not write HTML inside PHP, but vice versa - PHP inside HTML.
2. Use the null operator
3. Escape the output by default
i.e.

<tr class="tableGrey">
    <td>Фактический адрес</td>
    <td colspan="4"><?= htmlspecialchars($callCompanyData['result']['UF_CRM_1587463057321']) ?? ' ') ?></td>
</tr>

3. Learn how to use the Twig template engine, i.e.

<tr class="tableGrey">
    <td>Фактический адрес</td>
    <td colspan="4">{{ callCompanyData.result.UF_CRM_1587463057321 ?? ' ' }}</td>
</tr>

To write this output to a variable, you need to use the output buffering functions