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pieter78

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replace string pattern - advanced

Hi,

This question is a sequel to my previous one: https://www.experts-exchange.com/questions/21989717/replace-string-patterns.html#17523321
(has been answered).

The suggestion there works fine to replace [b]some text[/b] by <b>some text</b> and also checks whether the closing tag is present.

However, for creating a hyperlink or image link I would like to make it a little more advanced...

[link]www.somedomain.com[/link] should be converted to <a href='www.somedomain.com'>www.somedomain.com</a> ONLY if the closing [/link] is present.

[link=www.somedomain.com]Click me[/link] should be converted to <a href='www.somedomain.com'>Click me</a> ONLY if [/link] is present

and of course, [img]test.jpg[/img] or [img=test.jpg] needs to become <img src='test.jpg'>

The reason I ask instead of trying for many days myself, is that I do not need to learn the Regular Expressions - looks quite complicated - I just need these things, and I guess I am done then.

Looking forward... tolgaong, any inspiration left? ;-)

Regards,
Pieter
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tolgaong
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Well dont know if its a "nice" suggestion, but why reinvent the wheel that is allready spinning?

the phpBB forum is GNU based and contains the BBcode that actually does the same. And even more then you sugest, so why not tailor the code from phpBB and use that?

ie.

/**
 * Loads bbcode templates from the bbcode.htm file of the current template set.
 * Creates an array, keys are bbcode names like "b_open" or "url", values
 * are the associated template.
 * Probably pukes all over the place if there's something really screwed
 * with the bbcode.htm file.
 *
 * Nathan Codding, Sept 26 2001.
 */
function load_bbcode_template()
{
      global $template;
      $tpl_filename = $template->make_filename('bbcode.htm');
      $tpl = fread(fopen($tpl_filename, 'r'), filesize($tpl_filename));

      // replace \ with \\ and then ' with \'.
      $tpl = str_replace('\\', '\\\\', $tpl);
      $tpl  = str_replace('\'', '\\\'', $tpl);

      // strip newlines.
      $tpl  = str_replace("\n", '', $tpl);

      // Turn template blocks into PHP assignment statements for the values of $bbcode_tpls..
      $tpl = preg_replace('#<!-- BEGIN (.*?) -->(.*?)<!-- END (.*?) -->#', "\n" . '$bbcode_tpls[\'\\1\'] = \'\\2\';', $tpl);

      $bbcode_tpls = array();

      eval($tpl);

      return $bbcode_tpls;
}


/**
 * Prepares the loaded bbcode templates for insertion into preg_replace()
 * or str_replace() calls in the bbencode_second_pass functions. This
 * means replacing template placeholders with the appropriate preg backrefs
 * or with language vars. NOTE: If you change how the regexps work in
 * bbencode_second_pass(), you MUST change this function.
 *
 * Nathan Codding, Sept 26 2001
 *
 */
function prepare_bbcode_template($bbcode_tpl)
{
      global $lang;

      $bbcode_tpl['olist_open'] = str_replace('{LIST_TYPE}', '\\1', $bbcode_tpl['olist_open']);

      $bbcode_tpl['color_open'] = str_replace('{COLOR}', '\\1', $bbcode_tpl['color_open']);

      $bbcode_tpl['size_open'] = str_replace('{SIZE}', '\\1', $bbcode_tpl['size_open']);

      $bbcode_tpl['quote_open'] = str_replace('{L_QUOTE}', $lang['Quote'], $bbcode_tpl['quote_open']);

      $bbcode_tpl['quote_username_open'] = str_replace('{L_QUOTE}', $lang['Quote'], $bbcode_tpl['quote_username_open']);
      $bbcode_tpl['quote_username_open'] = str_replace('{L_WROTE}', $lang['wrote'], $bbcode_tpl['quote_username_open']);
      $bbcode_tpl['quote_username_open'] = str_replace('{USERNAME}', '\\1', $bbcode_tpl['quote_username_open']);

      $bbcode_tpl['code_open'] = str_replace('{L_CODE}', $lang['Code'], $bbcode_tpl['code_open']);

      $bbcode_tpl['img'] = str_replace('{URL}', '\\1', $bbcode_tpl['img']);
      $bbcode_tpl['img_script'] = str_replace('{SCRIPT}', '\\1', $bbcode_tpl['img_script']);

      // We do URLs in several different ways..
      $bbcode_tpl['url1'] = str_replace('{URL}', '\\1', $bbcode_tpl['url']);
      $bbcode_tpl['url1'] = str_replace('{DESCRIPTION}', '\\1', $bbcode_tpl['url1']);

      $bbcode_tpl['url2'] = str_replace('{URL}', 'http://\\1', $bbcode_tpl['url']);
      $bbcode_tpl['url2'] = str_replace('{DESCRIPTION}', '\\1', $bbcode_tpl['url2']);

      $bbcode_tpl['url3'] = str_replace('{URL}', '\\1', $bbcode_tpl['url']);
      $bbcode_tpl['url3'] = str_replace('{DESCRIPTION}', '\\2', $bbcode_tpl['url3']);

      $bbcode_tpl['url4'] = str_replace('{URL}', 'http://\\1', $bbcode_tpl['url']);
      $bbcode_tpl['url4'] = str_replace('{DESCRIPTION}', '\\3', $bbcode_tpl['url4']);

      $bbcode_tpl['email'] = str_replace('{EMAIL}', '\\1', $bbcode_tpl['email']);

      define("BBCODE_TPL_READY", true);

      return $bbcode_tpl;
}


/**
 * Does second-pass bbencoding. This should be used before displaying the message in
 * a thread. Assumes the message is already first-pass encoded, and we are given the
 * correct UID as used in first-pass encoding.
 */
function bbencode_second_pass($text, $uid, $signature = false)
{
      global $lang, $bbcode_tpl;

      // pad it with a space so we can distinguish between FALSE and matching the 1st char (index 0).
      // This is important; bbencode_quote(), bbencode_list(), and bbencode_code() all depend on it.
      $text = " " . $text;

      // First: If there isn't a "[" and a "]" in the message, don't bother.
      if (! (strpos($text, "[") && strpos($text, "]")) )
      {
            // Remove padding, return.
            $text = substr($text, 1);
            return $text;
      }

      // Only load the templates ONCE..
      if (!defined("BBCODE_TPL_READY"))
      {
            // load templates from file into array.
            $bbcode_tpl = load_bbcode_template();

            // prepare array for use in regexps.
            $bbcode_tpl = prepare_bbcode_template($bbcode_tpl);
      }

      if (!$signature)
      {
            // [CODE] and [/CODE] for posting code (HTML, PHP, C etc etc) in your posts.
            $text = bbencode_second_pass_code($text, $uid, $bbcode_tpl);

            // [QUOTE] and [/QUOTE] for posting replies with quote, or just for quoting stuff.
            $text = str_replace("[quote:$uid]", $bbcode_tpl['quote_open'], $text);
            $text = str_replace("[/quote:$uid]", $bbcode_tpl['quote_close'], $text);

            // New one liner to deal with opening quotes with usernames...
            // replaces the two line version that I had here before..
            $text = preg_replace("/\[quote:$uid=\"(.*?)\"\]/si", $bbcode_tpl['quote_username_open'], $text);

            // [list] and [list=x] for (un)ordered lists.
            // unordered lists
            $text = str_replace("[list:$uid]", $bbcode_tpl['ulist_open'], $text);
            // li tags
            $text = str_replace("[*:$uid]", $bbcode_tpl['listitem'], $text);
            // ending tags
            $text = str_replace("[/list:u:$uid]", $bbcode_tpl['ulist_close'], $text);
            $text = str_replace("[/list:o:$uid]", $bbcode_tpl['olist_close'], $text);
            // Ordered lists
            $text = preg_replace("/\[list=([a1]):$uid\]/si", $bbcode_tpl['olist_open'], $text);
      }

      // colours
      $text = preg_replace("/\[color=(\#[0-9A-F]{6}|[a-z]+):$uid\]/si", $bbcode_tpl['color_open'], $text);
      $text = str_replace("[/color:$uid]", $bbcode_tpl['color_close'], $text);

      if (!$signature)
      {
            // size
            $text = preg_replace("/\[size=([1-2][0-9]):$uid\]/si", $bbcode_tpl['size_open'], $text);
            $text = str_replace("[/size:$uid]", $bbcode_tpl['size_close'], $text);
      }
      else
      {
            // size
            $text = preg_replace("/\[size=(1[0-7]):$uid\]/si", $bbcode_tpl['size_open'], $text);
            $text = preg_replace("/\[size=([0-9]):$uid\]/si", $bbcode_tpl['size_open'], $text);
            $text = str_replace("[/size:$uid]", $bbcode_tpl['size_close'], $text);
      }

      // [b] and [/b] for bolding text.
      $text = str_replace("[b:$uid]", $bbcode_tpl['b_open'], $text);
      $text = str_replace("[/b:$uid]", $bbcode_tpl['b_close'], $text);

      // [u] and [/u] for underlining text.
      $text = str_replace("[u:$uid]", $bbcode_tpl['u_open'], $text);
      $text = str_replace("[/u:$uid]", $bbcode_tpl['u_close'], $text);

      // [i] and [/i] for italicizing text.
      $text = str_replace("[i:$uid]", $bbcode_tpl['i_open'], $text);
      $text = str_replace("[/i:$uid]", $bbcode_tpl['i_close'], $text);

      // Patterns and replacements for URL and email tags..
      $patterns = array();
      $replacements = array();

      //if (!$signature)
      //{
            // [img]image_url_here[/img] code..
            // This one gets first-passed..
            $patterns[] = "#\[img:$uid\](.*?)\[/img:$uid\]#si";
            $rand = rand();
            //print $rand . "<br>\n";
            $img = str_replace("{NAME}", $rand, $bbcode_tpl['img']);
            //print $img . "<br>\n";
            $replacements[] = $img;
      //}

      // matches a [url]xxxx://www.phpbb.com[/url] code..
      $patterns[] = "#\[url\]([\w]+?://[^ \"\n\r\t<]*?)\[/url\]#is";
      $replacements[] = $bbcode_tpl['url1'];

      // [url]www.phpbb.com[/url] code.. (no xxxx:// prefix).
      $patterns[] = "#\[url\]((www|ftp)\.[^ \"\n\r\t<]*?)\[/url\]#is";
      $replacements[] = $bbcode_tpl['url2'];

      // [url=xxxx://www.phpbb.com]phpBB[/url] code..
      $patterns[] = "#\[url=([\w]+?://[^ \"\n\r\t<]*?)\](.*?)\[/url\]#is";
      $replacements[] = $bbcode_tpl['url3'];

      // [url=www.phpbb.com]phpBB[/url] code.. (no xxxx:// prefix).
      $patterns[] = "#\[url=((www|ftp)\.[^ \"\n\r\t<]*?)\](.*?)\[/url\]#is";
      $replacements[] = $bbcode_tpl['url4'];

      // [email]user@domain.tld[/email] code..
      $patterns[] = "#\[email\]([a-z0-9&\-_.]+?@[\w\-]+\.([\w\-\.]+\.)?[\w]+)\[/email\]#si";
      $replacements[] = $bbcode_tpl['email'];

      $text = preg_replace($patterns, $replacements, $text);

      // Remove our padding from the string..
      $text = substr($text, 1);

      return $text;

} // bbencode_second_pass()

// Need to initialize the random numbers only ONCE
mt_srand( (double) microtime() * 1000000);

function make_bbcode_uid()
{
      // Unique ID for this message..

      $uid = md5(mt_rand());
      $uid = substr($uid, 0, BBCODE_UID_LEN);

      return $uid;
}

function bbencode_first_pass($text, $uid)
{
      // pad it with a space so we can distinguish between FALSE and matching the 1st char (index 0).
      // This is important; bbencode_quote(), bbencode_list(), and bbencode_code() all depend on it.
      $text = " " . $text;

      // [CODE] and [/CODE] for posting code (HTML, PHP, C etc etc) in your posts.
      $text = bbencode_first_pass_pda($text, $uid, '[code]', '[/code]', '', true, '');

      // [QUOTE] and [/QUOTE] for posting replies with quote, or just for quoting stuff.
      $text = bbencode_first_pass_pda($text, $uid, '[quote]', '[/quote]', '', false, '');
      $text = bbencode_first_pass_pda($text, $uid, '/\[quote=(\\\".*?\\\")\]/is', '[/quote]', '', false, '', "[quote:$uid=\\1]");

      // [list] and [list=x] for (un)ordered lists.
      $open_tag = array();
      $open_tag[0] = "[list]";

      // unordered..
      $text = bbencode_first_pass_pda($text, $uid, $open_tag, "[/list]", "[/list:u]", false, 'replace_listitems');

      $open_tag[0] = "[list=1]";
      $open_tag[1] = "[list=a]";

      // ordered.
      $text = bbencode_first_pass_pda($text, $uid, $open_tag, "[/list]", "[/list:o]",  false, 'replace_listitems');

      // [color] and [/color] for setting text color
      $text = preg_replace("#\[color=(\#[0-9A-F]{6}|[a-z\-]+)\](.*?)\[/color\]#si", "[color=\\1:$uid]\\2[/color:$uid]", $text);

      // [size] and [/size] for setting text size
      $text = preg_replace("#\[size=([1-2]?[0-9])\](.*?)\[/size\]#si", "[size=\\1:$uid]\\2[/size:$uid]", $text);

      // [b] and [/b] for bolding text.
      $text = preg_replace("#\[b\](.*?)\[/b\]#si", "[b:$uid]\\1[/b:$uid]", $text);

      // [u] and [/u] for underlining text.
      $text = preg_replace("#\[u\](.*?)\[/u\]#si", "[u:$uid]\\1[/u:$uid]", $text);

      // [i] and [/i] for italicizing text.
      $text = preg_replace("#\[i\](.*?)\[/i\]#si", "[i:$uid]\\1[/i:$uid]", $text);

      // [img]image_url_here[/img] code..
      $text = preg_replace("#\[img\]((ht|f)tp://)([^\r\n\t<\"]*?)\[/img\]#sie", "'[img:$uid]\\1' . str_replace(' ', '%20', '\\3') . '[/img:$uid]'", $text);

      // Remove our padding from the string..
      return substr($text, 1);;

} // bbencode_first_pass()

/**
 * $text - The text to operate on.
 * $uid - The UID to add to matching tags.
 * $open_tag - The opening tag to match. Can be an array of opening tags.
 * $close_tag - The closing tag to match.
 * $close_tag_new - The closing tag to replace with.
 * $mark_lowest_level - boolean - should we specially mark the tags that occur
 *                               at the lowest level of nesting? (useful for [code], because
 *                                    we need to match these tags first and transform HTML tags
 *                                    in their contents..
 * $func - This variable should contain a string that is the name of a function.
 *                        That function will be called when a match is found, and passed 2
 *                        parameters: ($text, $uid). The function should return a string.
 *                        This is used when some transformation needs to be applied to the
 *                        text INSIDE a pair of matching tags. If this variable is FALSE or the
 *                        empty string, it will not be executed.
 * If open_tag is an array, then the pda will try to match pairs consisting of
 * any element of open_tag followed by close_tag. This allows us to match things
 * like [list=A]...[/list] and [list=1]...[/list] in one pass of the PDA.
 *
 * NOTES:      - this function assumes the first character of $text is a space.
 *                        - every opening tag and closing tag must be of the [...] format.
 */
function bbencode_first_pass_pda($text, $uid, $open_tag, $close_tag, $close_tag_new, $mark_lowest_level, $func, $open_regexp_replace = false)
{
      $open_tag_count = 0;

      if (!$close_tag_new || ($close_tag_new == ''))
      {
            $close_tag_new = $close_tag;
      }

      $close_tag_length = strlen($close_tag);
      $close_tag_new_length = strlen($close_tag_new);
      $uid_length = strlen($uid);

      $use_function_pointer = ($func && ($func != ''));

      $stack = array();

      if (is_array($open_tag))
      {
            if (0 == count($open_tag))
            {
                  // No opening tags to match, so return.
                  return $text;
            }
            $open_tag_count = count($open_tag);
      }
      else
      {
            // only one opening tag. make it into a 1-element array.
            $open_tag_temp = $open_tag;
            $open_tag = array();
            $open_tag[0] = $open_tag_temp;
            $open_tag_count = 1;
      }

      $open_is_regexp = false;

      if ($open_regexp_replace)
      {
            $open_is_regexp = true;
            if (!is_array($open_regexp_replace))
            {
                  $open_regexp_temp = $open_regexp_replace;
                  $open_regexp_replace = array();
                  $open_regexp_replace[0] = $open_regexp_temp;
            }
      }

      if ($mark_lowest_level && $open_is_regexp)
      {
            message_die(GENERAL_ERROR, "Unsupported operation for bbcode_first_pass_pda().");
      }

      // Start at the 2nd char of the string, looking for opening tags.
      $curr_pos = 1;
      while ($curr_pos && ($curr_pos < strlen($text)))
      {
            $curr_pos = strpos($text, "[", $curr_pos);

            // If not found, $curr_pos will be 0, and the loop will end.
            if ($curr_pos)
            {
                  // We found a [. It starts at $curr_pos.
                  // check if it's a starting or ending tag.
                  $found_start = false;
                  $which_start_tag = "";
                  $start_tag_index = -1;

                  for ($i = 0; $i < $open_tag_count; $i++)
                  {
                        // Grab everything until the first "]"...
                        $possible_start = substr($text, $curr_pos, strpos($text, ']', $curr_pos + 1) - $curr_pos + 1);

                        //
                        // We're going to try and catch usernames with "[' characters.
                        //
                        if( preg_match('#\[quote=\\\"#si', $possible_start, $match) && !preg_match('#\[quote=\\\"(.*?)\\\"\]#si', $possible_start) )
                        {
                              // OK we are in a quote tag that probably contains a ] bracket.
                              // Grab a bit more of the string to hopefully get all of it..
                              if ($close_pos = strpos($text, '"]', $curr_pos + 9))
                              {
                                    if (strpos(substr($text, $curr_pos + 9, $close_pos - ($curr_pos + 9)), '[quote') === false)
                                    {
                                          $possible_start = substr($text, $curr_pos, $close_pos - $curr_pos + 2);
                                    }
                              }
                        }

                        // Now compare, either using regexp or not.
                        if ($open_is_regexp)
                        {
                              $match_result = array();
                              if (preg_match($open_tag[$i], $possible_start, $match_result))
                              {
                                    $found_start = true;
                                    $which_start_tag = $match_result[0];
                                    $start_tag_index = $i;
                                    break;
                              }
                        }
                        else
                        {
                              // straightforward string comparison.
                              if (0 == strcasecmp($open_tag[$i], $possible_start))
                              {
                                    $found_start = true;
                                    $which_start_tag = $open_tag[$i];
                                    $start_tag_index = $i;
                                    break;
                              }
                        }
                  }

                  if ($found_start)
                  {
                        // We have an opening tag.
                        // Push its position, the text we matched, and its index in the open_tag array on to the stack, and then keep going to the right.
                        $match = array("pos" => $curr_pos, "tag" => $which_start_tag, "index" => $start_tag_index);
                        bbcode_array_push($stack, $match);
                        //
                        // Rather than just increment $curr_pos
                        // Set it to the ending of the tag we just found
                        // Keeps error in nested tag from breaking out
                        // of table structure..
                        //
                        $curr_pos += strlen($possible_start);
                  }
                  else
                  {
                        // check for a closing tag..
                        $possible_end = substr($text, $curr_pos, $close_tag_length);
                        if (0 == strcasecmp($close_tag, $possible_end))
                        {
                              // We have an ending tag.
                              // Check if we've already found a matching starting tag.
                              if (sizeof($stack) > 0)
                              {
                                    // There exists a starting tag.
                                    $curr_nesting_depth = sizeof($stack);
                                    // We need to do 2 replacements now.
                                    $match = bbcode_array_pop($stack);
                                    $start_index = $match['pos'];
                                    $start_tag = $match['tag'];
                                    $start_length = strlen($start_tag);
                                    $start_tag_index = $match['index'];

                                    if ($open_is_regexp)
                                    {
                                          $start_tag = preg_replace($open_tag[$start_tag_index], $open_regexp_replace[$start_tag_index], $start_tag);
                                    }

                                    // everything before the opening tag.
                                    $before_start_tag = substr($text, 0, $start_index);

                                    // everything after the opening tag, but before the closing tag.
                                    $between_tags = substr($text, $start_index + $start_length, $curr_pos - $start_index - $start_length);

                                    // Run the given function on the text between the tags..
                                    if ($use_function_pointer)
                                    {
                                          $between_tags = $func($between_tags, $uid);
                                    }

                                    // everything after the closing tag.
                                    $after_end_tag = substr($text, $curr_pos + $close_tag_length);

                                    // Mark the lowest nesting level if needed.
                                    if ($mark_lowest_level && ($curr_nesting_depth == 1))
                                    {
                                          if ($open_tag[0] == '[code]')
                                          {
                                                $code_entities_match = array('#<#', '#>#', '#"#', '#:#', '#\[#', '#\]#', '#\(#', '#\)#', '#\{#', '#\}#');
                                                $code_entities_replace = array('&lt;', '&gt;', '&quot;', '&#58;', '&#91;', '&#93;', '&#40;', '&#41;', '&#123;', '&#125;');
                                                $between_tags = preg_replace($code_entities_match, $code_entities_replace, $between_tags);
                                          }
                                          $text = $before_start_tag . substr($start_tag, 0, $start_length - 1) . ":$curr_nesting_depth:$uid]";
                                          $text .= $between_tags . substr($close_tag_new, 0, $close_tag_new_length - 1) . ":$curr_nesting_depth:$uid]";
                                    }
                                    else
                                    {
                                          if ($open_tag[0] == '[code]')
                                          {
                                                $text = $before_start_tag . '&#91;code&#93;';
                                                $text .= $between_tags . '&#91;/code&#93;';
                                          }
                                          else
                                          {
                                                if ($open_is_regexp)
                                                {
                                                      $text = $before_start_tag . $start_tag;
                                                }
                                                else
                                                {
                                                      $text = $before_start_tag . substr($start_tag, 0, $start_length - 1) . ":$uid]";
                                                }
                                                $text .= $between_tags . substr($close_tag_new, 0, $close_tag_new_length - 1) . ":$uid]";
                                          }
                                    }

                                    $text .= $after_end_tag;

                                    // Now.. we've screwed up the indices by changing the length of the string.
                                    // So, if there's anything in the stack, we want to resume searching just after it.
                                    // otherwise, we go back to the start.
                                    if (sizeof($stack) > 0)
                                    {
                                          $match = bbcode_array_pop($stack);
                                          $curr_pos = $match['pos'];
//                                          bbcode_array_push($stack, $match);
//                                          ++$curr_pos;
                                    }
                                    else
                                    {
                                          $curr_pos = 1;
                                    }
                              }
                              else
                              {
                                    // No matching start tag found. Increment pos, keep going.
                                    ++$curr_pos;
                              }
                        }
                        else
                        {
                              // No starting tag or ending tag.. Increment pos, keep looping.,
                              ++$curr_pos;
                        }
                  }
            }
      } // while

      return $text;

} // bbencode_first_pass_pda()

/**
 * Does second-pass bbencoding of the [code] tags. This includes
 * running htmlspecialchars() over the text contained between
 * any pair of [code] tags that are at the first level of
 * nesting. Tags at the first level of nesting are indicated
 * by this format: [code:1:$uid] ... [/code:1:$uid]
 * Other tags are in this format: [code:$uid] ... [/code:$uid]
 */
function bbencode_second_pass_code($text, $uid, $bbcode_tpl)
{
      global $lang;

      $code_start_html = $bbcode_tpl['code_open'];
      $code_end_html =  $bbcode_tpl['code_close'];

      // First, do all the 1st-level matches. These need an htmlspecialchars() run,
      // so they have to be handled differently.
      $match_count = preg_match_all("#\[code:1:$uid\](.*?)\[/code:1:$uid\]#si", $text, $matches);

      for ($i = 0; $i < $match_count; $i++)
      {
            $before_replace = $matches[1][$i];
            $after_replace = $matches[1][$i];

            // Replace 2 spaces with "&nbsp; " so non-tabbed code indents without making huge long lines.
            $after_replace = str_replace("  ", "&nbsp; ", $after_replace);
            // now Replace 2 spaces with " &nbsp;" to catch odd #s of spaces.
            $after_replace = str_replace("  ", " &nbsp;", $after_replace);

            // Replace tabs with "&nbsp; &nbsp;" so tabbed code indents sorta right without making huge long lines.
            $after_replace = str_replace("\t", "&nbsp; &nbsp;", $after_replace);

            // now Replace space occurring at the beginning of a line
            $after_replace = preg_replace("/^ {1}/m", '&nbsp;', $after_replace);

            $str_to_match = "[code:1:$uid]" . $before_replace . "[/code:1:$uid]";

            $replacement = $code_start_html;
            $replacement .= $after_replace;
            $replacement .= $code_end_html;

            $text = str_replace($str_to_match, $replacement, $text);
      }

      // Now, do all the non-first-level matches. These are simple.
      $text = str_replace("[code:$uid]", $code_start_html, $text);
      $text = str_replace("[/code:$uid]", $code_end_html, $text);

      return $text;

} // bbencode_second_pass_code()

/**
 * Rewritten by Nathan Codding - Feb 6, 2001.
 * - Goes through the given string, and replaces xxxx://yyyy with an HTML <a> tag linking
 *       to that URL
 * - Goes through the given string, and replaces www.xxxx.yyyy[zzzz] with an HTML <a> tag linking
 *       to http://www.xxxx.yyyy[/zzzz]
 * - Goes through the given string, and replaces xxxx@yyyy with an HTML mailto: tag linking
 *            to that email address
 * - Only matches these 2 patterns either after a space, or at the beginning of a line
 *
 * Notes: the email one might get annoying - it's easy to make it more restrictive, though.. maybe
 * have it require something like xxxx@yyyy.zzzz or such. We'll see.
 */
function make_clickable($text)
{

      // pad it with a space so we can match things at the start of the 1st line.
      $ret = ' ' . $text;

      // matches an "xxxx://yyyy" URL at the start of a line, or after a space.
      // xxxx can only be alpha characters.
      // yyyy is anything up to the first space, newline, comma, double quote or <
      $ret = preg_replace("#(^|[\n ])([\w]+?://[^ \"\n\r\t<]*)#is", "\\1<a href=\"\\2\" target=\"_blank\">\\2</a>", $ret);

      // matches a "www|ftp.xxxx.yyyy[/zzzz]" kinda lazy URL thing
      // Must contain at least 2 dots. xxxx contains either alphanum, or "-"
      // zzzz is optional.. will contain everything up to the first space, newline,
      // comma, double quote or <.
      $ret = preg_replace("#(^|[\n ])((www|ftp)\.[^ \"\t\n\r<]*)#is", "\\1<a href=\"http://\\2\" target=\"_blank\">\\2</a>", $ret);

      // matches an email@domain type address at the start of a line, or after a space.
      // Note: Only the followed chars are valid; alphanums, "-", "_" and or ".".
      $ret = preg_replace("#(^|[\n ])([a-z0-9&\-_.]+?)@([\w\-]+\.([\w\-\.]+\.)*[\w]+)#i", "\\1<a href=\"mailto:\\2@\\3\">\\2@\\3</a>", $ret);

      // Remove our padding..
      $ret = substr($ret, 1);

      return($ret);
}

/**
 * Nathan Codding - Feb 6, 2001
 * Reverses the effects of make_clickable(), for use in editpost.
 * - Does not distinguish between "www.xxxx.yyyy" and "http://aaaa.bbbb" type URLs.
 *
 */
function undo_make_clickable($text)
{
      $text = preg_replace("#<!-- BBCode auto-link start --><a href=\"(.*?)\" target=\"_blank\">.*?</a><!-- BBCode auto-link end -->#i", "\\1", $text);
      $text = preg_replace("#<!-- BBcode auto-mailto start --><a href=\"mailto:(.*?)\">.*?</a><!-- BBCode auto-mailto end -->#i", "\\1", $text);

      return $text;

}

/**
 * Nathan Codding - August 24, 2000.
 * Takes a string, and does the reverse of the PHP standard function
 * htmlspecialchars().
 */
function undo_htmlspecialchars($input)
{
      $input = preg_replace("/&gt;/i", ">", $input);
      $input = preg_replace("/&lt;/i", "<", $input);
      $input = preg_replace("/&quot;/i", "\"", $input);
      $input = preg_replace("/&amp;/i", "&", $input);

      return $input;
}

/**
 * This is used to change a [*] tag into a [*:$uid] tag as part
 * of the first-pass bbencoding of [list] tags. It fits the
 * standard required in order to be passed as a variable
 * function into bbencode_first_pass_pda().
 */
function replace_listitems($text, $uid)
{
      $text = str_replace("[*]", "[*:$uid]", $text);

      return $text;
}

/**
 * Escapes the "/" character with "\/". This is useful when you need
 * to stick a runtime string into a PREG regexp that is being delimited
 * with slashes.
 */
function escape_slashes($input)
{
      $output = str_replace('/', '\/', $input);
      return $output;
}

/**
 * This function does exactly what the PHP4 function array_push() does
 * however, to keep phpBB compatable with PHP 3 we had to come up with our own
 * method of doing it.
 */
function bbcode_array_push(&$stack, $value)
{
   $stack[] = $value;
   return(sizeof($stack));
}

/**
 * This function does exactly what the PHP4 function array_pop() does
 * however, to keep phpBB compatable with PHP 3 we had to come up with our own
 * method of doing it.
 */
function bbcode_array_pop(&$stack)
{
   $arrSize = count($stack);
   $x = 1;

   while(list($key, $val) = each($stack))
   {
        if($x < count($stack))
        {
                   $tmpArr[] = $val;
        }
        else
        {
                   $return_val = $val;
        }
        $x++;
   }
   $stack = $tmpArr;

   return($return_val);
}

//
// Smilies code ... would this be better tagged on to the end of bbcode.php?
// Probably so and I'll move it before B2
//
function smilies_pass($message)
{
      static $orig, $repl;

      if (!isset($orig))
      {
            global $db, $general_config;
            $orig = $repl = array();

            $sql = 'SELECT * FROM ' . SMILIES_TABLE;
            if( !$result = $db->sql_query($sql) )
            {
                  message_die(GENERAL_ERROR, "Couldn't obtain smilies data", "", "", __LINE__, __FILE__, $sql);
            }
            $smilies = $db->sql_fetchrowset($result);

            if (count($smilies))
            {
                  usort($smilies, 'smiley_sort');
            }

            for ($i = 0; $i < count($smilies); $i++)
            {
                  $orig[] = "/(?<=.\W|\W.|^\W)" . slash_preg_quote($smilies[$i]['code'], "/") . "(?=.\W|\W.|\W$)/";
                  $repl[] = '<img src="http://' . $general_config['server_name'] . $general_config['script_path'] . $general_config['smiley_path'] . '/' . $smilies[$i]['smile_url'] . '" alt="' . $smilies[$i]['emoticon'] . '" title="' . $smilies[$i]['emoticon'] . '" />';
            }
      }

      if (count($orig))
      {
            $message = preg_replace($orig, $repl, ' ' . $message . ' ');
            $message = substr($message, 1, -1);
      }

      return $message;
}

function smiley_sort($a, $b)
{
      if ( strlen($a['code']) == strlen($b['code']) )
      {
            return 0;
      }

      return ( strlen($a['code']) > strlen($b['code']) ) ? -1 : 1;
}
Avatar of pieter78
pieter78

ASKER

Tolga, thanks: it works, although I added some modifiers to add http:// in the beginning in case the user starts the link directly with www... Everything works now as I wanted it to work!

Chris: thanks for the advice, but this is too much. I like to understand the wheel a little, and this code has too much in it (also things that I dot use). The first answer was easier to modify for several specific things I needed to add later on.

Now it all works like I meant. However, I got a last idea, which would be nice, but not necessary. For those with inspiration and enthusiasm: https://www.experts-exchange.com/questions/21991939/string-thing-the-trilogy-completed.html

Tolga, thanks again!