Amigo Secreto

amigo_secreto.php

<?php

function amigoSecreto(array $people)
{
    shuffle($people);
    $temp = array();

    do {
        array_push($temp, current($people), next($people));
    } while(current($people));

    array_splice($temp, -1, 1, [reset($temp)]);

    return array_chunk($temp, 2);
}

$friends = amigoSecreto(["fulano", "ciclano", "beltrano", "zé"]);

print_r($friends);