Randomimize array inside function PHP

please help me. My function pick up keywords from string(text) and replace them with href tag, that working fine so far, but now I want (because expecting more then one keyword occurrence in string) replace each with random URL address from array, check out code to see what I want and what I get. Thank you in advance!!

$url_array = array('https://google.com/somelink1', 'https://google.com/somelink2', 'https://google.com/somelink3'); 
$search = 'Whatever text here text also this is about text';
$str = 'text';

$give_me_back_text_with_edited_links_and_random_urls = replacekeywords($str, $search, $url_array);

//What do I get?
$give_me_back_text_with_edited_links_and_random_urls = 'Whatever <a href="https://google.com/somelink2">text</a> here <a href="https://google.com/somelink2">text</a> also this is about <a href="https://google.com/somelink2">text</a>';

//What I want?
$give_me_back_text_with_edited_links_and_random_urls ='Whatever <a href="https://google.com/somelink1">text</a> here <a href="https://google.com/somelink3">text</a> also this is about <a href="https://google.com/somelink2">text</a>';


function replacekeywords($str, $search, $url_array) {

    $occurrences = substr_count(strtolower($str), strtolower($search));
    $newstring = $str;
    $match = array();

    for ($i=0;$i<$occurrences;$i++) {


        // !!!!!!!!!! how do I make $url here randomly based on $url_array?
        $url = $url_array[rand(0, count($url_array) - 1)]; 


        $match[$i] = stripos($str, $search, $i);
        $match[$i] = substr($str, $match[$i], strlen($search));
        $newstring = preg_replace("/\b([a-z]*${match[$i]}[a-z]*)\b/i","<a href='".$url."' class='link'>$0</a>",strip_tags($newstring,'<br><p>'));
    }

     return $newstring;