SoftUni students collection sort

<?php
$students = explode("\n", $_GET['students']);

$id = 1;
$studentsCollection = [];
foreach ($students as $student) {
    if (empty($student)) continue;
    $student = explode(", ", $student);

    $studentsCollection[] = array(
        'Id' => $id++,
        'Username' => htmlspecialchars(($student[0])),
        'Email' => htmlspecialchars(($student[1])),
        'Type' => htmlspecialchars(($student[2])),
        'Result' => htmlspecialchars(trim($student[3]))
    );
}

foreach ($studentsCollection as $key => $val) {
    $ids[$key] = $val['Id'];
    $column[$key] = $val[ucfirst($_GET['column'])];
}

$order = strtolower($_GET['order']) == 'descending' ? SORT_DESC : SORT_ASC;
array_multisort($column, $order, $ids, $order, $studentsCollection);


echo "<table><thead><tr><th>Id</th><th>Username</th><th>Email</th><th>Type</th><th>Result</th></tr></thead>";
foreach ($studentsCollection as $row) {
    echo "<tr><td>{$row['Id']}</td><td>{$row['Username']}</td><td>{$row['Email']}</td><td>{$row['Type']}</td><td>{$row['Result']}</td></tr>";
}
echo "</table>";