pastebin - collaborative debugging

<?php
function markup($pat,$hay,$out = false) {
  global $groupstyles;
  global $hfieldset;
  global $out;
  $colorarray=array ('#F5FF80','#99FF80','#80FFFF','#809FFF','#FF80B8','#FFB380','#EBFFE6','#E6FFFF','#FF9900','#DABFFF','#FFF0E6','#FFF280','#FFCCBF','#BFCFFF','#FF9980','#FAFFE6','#31FFC1','#FF89FF','#FFC800','#FF6464','#22A2A2','#DDFF08','#FFCCFF','#FFCCCC','#FFCC99','#FFCC66','#FFCECE','#A095EE','#C9EAF3','#CFFEF0','#CAFFD8','#B4D1B6','#B3FF99','#DFDF00','#EDEF85','#2DC800');
  $hayLen = strlen($hay);
  $matches = true;
  $h = '';
  if (!$out) {
    $matches = preg_match_all($pat, $hay, $out, PREG_OFFSET_CAPTURE|PREG_SET_ORDER);
  }
  if ($matches) {
    $lastOff = 0;
      foreach ($out as $matchArr) { //each set of matches
        $origFull = $matchArr[0][0]; //full pat match
        $full = htmlentities($origFull);
        $fullOff = $matchArr[0][1];
        $fullLen = strlen($origFull);
        unset($matchArr[0]);
        if (!empty($matchArr)) {
          $fullChars = str_split($origFull);
            foreach ($fullChars as $k => $char) {
              $fullChars[$k] = htmlentities($char);
            }
            $i=0;
            $j=0;
            if(!isset($inds)){
              foreach ($matchArr as $ind=>$value) {
                $j++;
                $inds[$j]=array();
                $inds[$j]['name']=$ind;
              }
              $in=1;
              for ($k = 1; $k < count($inds)+1; $k++) {
                $inds[$k]['color']=$colorarray[$in]!='' ? $colorarray[$in] : $mycol='#CCCCCC';
                $in++;
                  if(!is_int($inds[$k]['name'])){
                    $inds[$k]['displayname']=$inds[$k+1]['name']." : '".$inds[$k]['name']."'";
                    $inds[$k]['name'].="_".$inds[$k+1]['name'];
                    $inds[$k]['span']="<span class='g".$inds[$k]['name']."'>";
                    $hfieldset.='<fieldset style="width:10px;padding:6px;margin:3px;background-color:'.$inds[$k]['color'].';display:inline;"><legend>'.$inds[$k]['displayname'].'</legend><input type="checkbox" value="'.$inds[$k]['color'].'" onclick="changecolor(this);" checked name="'.$inds[$k]['name'].'"></fieldset>&nbsp;';
                    $groupstyles .= "
  .g".$inds[$k]['name']." {background-color:".$inds[$k]['color'].";}
";
                    $inds[$k+1]['name']=$inds[$k]['name'];
                    $inds[$k+1]['span']='';
                    $inds[$k+1]['color']=$inds[$k]['color'];
                    $k++;
                  } else {
                    $inds[$k]['span']="<span class='g".$inds[$k]['name']."'>";
                    $hfieldset.='<fieldset style="width:10px;padding:6px;margin:3px;background-color:'.$inds[$k]['color'].';display:inline;"><legend>'.$inds[$k]['name'].'</legend><input type="checkbox" value="'.$inds[$k]['color'].'" onclick="changecolor(this);" checked name="g'.$inds[$k]['name'].'"></fieldset>&nbsp;';
                     $groupstyles .= "
  .g".$inds[$k]['name']." {background-color:".$inds[$k]['color'].";}
";                }
                }
              }
              foreach ($matchArr as $ind=>$subInfoArr) {
                $i++;
                $span = $inds[$i]['span']!='' ? $inds[$i]['span'] : '' ;
                $sub = $subInfoArr[0];
                $subLen = strlen($sub);
                $subOff = $subInfoArr[1] - $fullOff;
                $endOff = ($subOff + $subLen) - 1;
                $fullChars[$subOff] = $span.$fullChars[$subOff];
                $fullChars[$endOff] .= $inds[$i]['span']!='' ? '</span>' : '';
              }
              $full = implode('',$fullChars);
            }
            if ($fullOff == 0) {
              $left = '';
            } else {
              $left = substr($hay, $lastOff, $fullOff-$lastOff);
            }
            $lastOff = $fullOff + $fullLen;
            $h .= htmlentities($left)."<span class='g00'>$full</span>";
          }
          if ($lastOff < $hayLen) {
            $h .= htmlentities(substr($hay, $lastOff));
          }
          return $h;
        } else {
          return false;
     }
}
$matchpattern='/th(?<named1>is( is ))(?<named2>a ((t)e)s)t/';
$sourcetext='testing this is a test testing this is a test testing';
$hmarkup=markup($matchpattern,$sourcetext);
$highlightdiv="<div>HIGHLIGHTED MATCHES:<br><fieldset style='padding:8px;margin:5px;'><legend>CAPTURE GROUPS&nbsp;</span></legend><fieldset style='width:10px;padding:6px;margin:3px;background-color:#F5FF80;display:inline;'><legend>0</legend><input type='checkbox' value='#F5FF80' onclick='changecolor(this);' checked name='g00'></fieldset>&nbsp;$hfieldset<pre>$hmarkup</pre></div>";
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<style type="text/css">
  .g00 {background-color:#F5FF80;}<?php echo $groupstyles; ?>
</style>
<script type="text/javascript">
<!--
function changecolor(theBox)
{
  var obj=document.getElementsByTagName("span");
  for(var i=0,limit=obj.length;i<limit;++i)
  {
    if( -1<obj[i].className.indexOf(theBox.name) )
    {
      if( theBox.checked )
        obj[i].style.backgroundColor=theBox.value;
      else
        obj[i].style.backgroundColor='transparent';
    }
  }
}
//-->
</script>
</head>
<body>
MATCH PATTERN: <pre><?php echo htmlentities($matchpattern); ?></pre><hr>
<?php echo $highlightdiv;?>
</body>
</html>