Autohyperlinking - it's about to kill me...

[Anon]

I've worked on this on and off for a couple of months now, and, while I have gotten it to work 90% of the time, I think it's time to admit this project's to much for my limited abilities.

Anyway, what I'm trying to do is write a script that will convert any web url it comes across in a user's comment into a hyperlink. For example, if the url http://www.phpbuiler.com was found in a comment, the script would convert it http://www.phpbuilder.com into <a href=http://www.phpbuilder.com>http://www.phpbuilder.com</a>.

The code below works most of the time, but every know and then it runs into something(still haven't figured out what) that causes the script to time out. It's probably not the most efficient way to go about this either.... If anyone has any ideas or snippets of code to share I would be very grateful.

function print_comment($comment)
{
$whitespace = " ";
$whitespace .= $comment;
$comment = $whitespace;
$i = -1;
$urlpresent = "";
$urlcheck = "";

$comment .= " ";
$comment = ereg_replace("<br>","\n",$comment);

$comlength = strlen("$comment");
$urlpresent = ereg_replace("http://","urlisfoundheremofo",$comment);

{
$urlpresent == $comment;
}
if ($urlpresent != $comment)
{
$subcomment = $comment;
while ($urlcheck != "complete")
{
$toadd = 0;
++$i;
$startoflink[$i] = strpos($subcomment," http://");
++$startoflink[$i];

$spacecheck[$i] = $startoflink[$i];

$nextcheck = $spacecheck[$i] + 7;
$subcomlength = strlen("$subcomment");
$toadd = $comlength - $subcomlength;
$spacecheck[$i] = $spacecheck[$i] + $toadd;

$newcomlength = $comlength - $nextcheck;
$subcomment = substr($subcomment,$nextcheck, $newcomlength);
$urlpresent2 = ereg_replace("http://","urlisfoundheremofo",$subcomment);
if ($urlpresent2 == $subcomment)
{
$urlcheck = "complete";
}
}
}
$x = 0;
$maxi = $i;
while ($i > -1)
{
$checker = "";
while ($checker != " " and $checker != "\n")
{

$checker = substr($comment, $spacecheck[$i], 1);

if ($checker != " " and $checker != "\n")
{
$string[$i] .= $checker;
}
++$spacecheck[$i];

}

--$i;

}

$i = $maxi;

while ($i > -1)
{
while(!ereg("^{.*([[:alnum:]]|/)$",} $string[$i]))
{
$length = strlen("$string[$i]");
$toget = $length - 1;
$string[$i] = substr($string[$i], 0, $toget);
}
--$i;
}

sort($string);

$i = $maxi;
while ($i > -1)
{

$comment = ereg_replace(" $string[$i]"," <a href=$string[$i]>$string[$i]</a>",$comment);
--$i;
}
$comment = ereg_replace("\n","<br>",$comment);

print("$comment");
}

[Anon]

how about this approach... construct a new comment from the old by considering links as we see them

given $comment..

$total = strlen($comment);
$pos = 0;
$new_comment = "";

while($pos < $total) {
// Find the next position of a link in $comment
$new_pos = strstr("http://", $comment, $pos);

// Check if we've finished, ie. no new references found, so set the position to be at the end of the comment
if($new_pos == $pos) {
// Add what's left to the new comment
$new_comment .= substr($comment, $pos, $total);
$pos = $total;
} else {
// Add the stuff up to this reference
$new_comment .= substr($comment, $pos, $new_pos);

// We have a reference starting at $new_pos, extract it appropriately
$link = "";
$link_pos = $new_pos
while($comment[$link_pos] != " " && $link_pos < $total) {
  $link .= $comment[$link_pos];
  $link_pos++;
}
// Got the link, now add it to $new_comment
$new_comment .= "<a href=\"".$link."\">$link</a>";
// Update the position in the text
$pos = $link_pos;

}
}

It won't work perfectly (as i haven't tested it), but i think the idea is sound enough. you would want more checks in the loops (eg. a maximum link length), but technically this shouldn't time out as every cycle of the loop causes the position to be incremented (or the loop exited).

hope this helps

dom