PHP HtmlReplace input filter security function

 
//$rptype = 0 means that only HTML tags are replaced
//$rptype = 1 replaces the HTML tag and removes the contiguous whitespace character
//$rptype = 2 replaces the HTML tag and removes all whitespace characters
//$rptype = -1 means that only HTML dangerous tags are replaced
function HtmlReplace($str,$rptype=0) 
{ 
$str = stripslashes($str); 
if($rptype==0) 
{ 
$str = htmlspecialchars($str); 
} 
else if($rptype==1) 
{ 
$str = htmlspecialchars($str); 
$str = str_replace(" ",' ',$str); 
$str = ereg_replace("[rnt ]{1,}",' ',$str); 
} 
else if($rptype==2) 
{ 
$str = htmlspecialchars($str); 
$str = str_replace(" ",'',$str); 
$str = ereg_replace("[rnt ]",'',$str); 
} 
else 
{ 
$str = ereg_replace("[rnt ]{1,}",' ',$str); 
$str = eregi_replace('script',' The script ',$str); 
$str = eregi_replace("<[/]{0,1}(link|meta|ifr|fra)[^>]*>",'',$str); 
} 
return addslashes($str); 
}