i want to correct my recursive function in php - php

Question

I have a recursive function
first of all one array of page URLs are passed to this function
then for each link and finds links in those pages, if those are pdf links then saved to $li array, if not then saved to $next array.
actually, in some pages, same links repeating.
so every time I want to pass $next array with new links only.but now $next array is storing all links and loop is not ending.please help
here is my code
<?php
global $next;
$next == array();
global $counter;
$counter = 2;
global $p;
$next is an array of page links got from a page
next_iter = get_html1($next);
function get_html1($next){
global $li;
global $all_links;
global $p;
$p++;
echo "count is" . $p . '<br>';
error_reporting(E_ERROR | E_PARSE);
global $URL;
global $counter;
$next = array_unique($next);
print_r($next);
foreach ($next as $nw) {
$page = '';
if ((strpos($nw, $URL) !== false ) && (strpos($nw, 'http://') !== false || strpos($nw, 'https://') !== false)) {
$page = $nw;
$html1 = file_get_html($page);
} else if (strpos($nw, $URL) === false && strpos($nw, 'http://') === false && strpos($nw, 'https://') === false) {
$page = $URL . $nw;
$html1 = file_get_html($page);
}
if ($html1 !== false) {
foreach ($html1->find('a') as $links) {
if (!in_array($links->href, $all_links)) {
if ($links->href != '#' && $links->href != NULL && $links->href != '/' && strpos($links->href, 'javascript') === false) {
$a = strip_tags($links->plaintext);
$a = preg_replace("/\s| /", '', $a);
$a = trim($a);
if ((preg_match('/.*\.pdf$/i', $links->href)) || (strcmp($a, 'Download') == 0) || stripos($a, 'Download') !== false) {
// echo $links->href;
if ((strpos($links->href, 'http://') !== false || strpos($links->href, 'https://') !== false)) {
$lm = $links->href;
if (!in_array($lm, $li)) {
write_to_folder($lm);
$li[] = $lm;
}
$li[] = $links->href;
} else if ((strpos($links->href, 'http://') === false && strpos($links->href, 'https://') === false)) {
// echo $URL . $links->href . '<br>';
$lm = $URL . $links->href;
if (!in_array($lm, $li)) {
write_to_folder($lm);
$li[] = $lm;
}
}
} else {
if (strpos($links->href, 'mailto:') === false && strpos($links->href, 'tel:') === false && strpos($links->href, '.zip') === false) {
if (!in_array($links->href, $next1)) {
$next[] = $links->href;
}
}
}
}
}
}
}
}
$next = array_unique($next);
echo "<br>next array";
if (!empty($next)) {
if ($p <= $counter) {
$recursiv = get_html1($next);
} else {
echo "SUCCESSFULLY EXECUTED";
exit;
}
} else {
echo "SUCCESSFULLY EXECUTED";
exit;
}
}
?>