bbcode.php

<?php
/**
 * BBCode to HTML converter
 *
 * Created by Kai Mallea (kmallea@gmail.com)
 *
 * Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
 */


class BBCode {
  protected $bbcode_table = array();
  
  public function __construct () {
    
    // Replace [b]...[/b] with <strong>...</strong>
    $this->bbcode_table["/\[b\](.*?)\[\/b\]/is"] = function ($match) {
      return "<strong>$match[1]</strong>";
    };


    // Replace [i]...[/i] with <em>...</em>
    $this->bbcode_table["/\[i\](.*?)\[\/i\]/is"] = function ($match) {
      return "<em>$match[1]</em>";
    };


    // Replace [code]...[/code] with <pre><code>...</code></pre>
    $this->bbcode_table["/\[code\](.*?)\[\/code\]/is"] = function ($match) {
      return "<pre><code>$match[1]</code></pre>";  
    };


    // Replace [quote]...[/quote] with <blockquote><p>...</p></blockquote>
    $this->bbcode_table["/\[quote\](.*?)\[\/quote\]/is"] = function ($match) {
      return "<blockquote><p>$match[1]</p></blockquote>";
    };


    // Replace [quote="person"]...[/quote] with <blockquote><p>...</p></blockquote>
    $this->bbcode_table["/\[quote=\"([^\"]+)\"\](.*?)\[\/quote\]/is"] = function ($match) {
      return "$match[1] wrote: <blockquote><p>$match[2]</p></blockquote>";
    };

    
    // Replace [size=30]...[/size] with <span style="font-size:30%">...</span>
    $this->bbcode_table["/\[size=(\d+)\](.*?)\[\/size\]/is"] = function ($match) {
      return "<span style=\"font-size:$match[1]%\">$match[2]</span>";
    };


    // Replace [s] with <del>
    $this->bbcode_table["/\[s\](.*?)\[\/s\]/is"] = function ($match) {
      return "<del>$match[1]</del>";
    };


    // Replace [u]...[/u] with <span style="text-decoration:underline;">...</span>
    $this->bbcode_table["/\[u\](.*?)\[\/u\]/is"] = function ($match) {
      return '<span style="text-decoration:underline;">' . $match[1] . '</span>';
    };

    
    // Replace [center]...[/center] with <div style="text-align:center;">...</div>
    $this->bbcode_table["/\[center\](.*?)\[\/center\]/is"] = function ($match) {
      return '<div style="text-align:center;">' . $match[1] . '</div>';
    };


    // Replace [color=somecolor]...[/color] with <span style="color:somecolor">...</span>
    $this->bbcode_table["/\[color=([#a-z0-9]+)\](.*?)\[\/color\]/is"] = function ($match) {
      return '<span style="color:'. $match[1] . ';">' . $match[2] . '</span>';
    };


    // Replace [email]...[/email] with <a href="mailto:...">...</a>
    $this->bbcode_table["/\[email\](.*?)\[\/email\]/is"] = function ($match) {
      return "<a href=\"mailto:$match[1]\">$match[1]</a>"; 
    };


    // Replace [email=someone@somewhere.com]An e-mail link[/email] with <a href="mailto:someone@somewhere.com">An e-mail link</a>
    $this->bbcode_table["/\[email=(.*?)\](.*?)\[\/email\]/is"] = function ($match) {
      return "<a href=\"mailto:$match[1]\">$match[2]</a>"; 
    };


    // Replace [url]...[/url] with <a href="...">...</a>
    $this->bbcode_table["/\[url\](.*?)\[\/url\]/is"] = function ($match) {
      return "<a href=\"$match[1]\">$match[1]</a>"; 
    };

    
    // Replace [url=http://www.google.com/]A link to google[/url] with <a href="http://www.google.com/">A link to google</a>
    $this->bbcode_table["/\[url=(.*?)\](.*?)\[\/url\]/is"] = function ($match) {
      return "<a href=\"$match[1]\">$match[2]</a>"; 
    };
    

    // Replace [img]...[/img] with <img src="..."/>
    $this->bbcode_table["/\[img\](.*?)\[\/img\]/is"] = function ($match) {
      return "<img src=\"$match[1]\"/>"; 
    };
    
    
    // Replace [list]...[/list] with <ul><li>...</li></ul>
    $this->bbcode_table["/\[list\](.*?)\[\/list\]/is"] = function ($match) {
      $match[1] = preg_replace_callback("/\[\*\]([^\[\*\]]*)/is", function ($submatch) {
        return "<li>" . preg_replace("/[\n\r?]$/", "", $submatch[1]) . "</li>";
      }, $match[1]);

      return "<ul>" . preg_replace("/[\n\r?]/", "", $match[1]) . "</ul>";
    };


    // Replace [list=1|a]...[/list] with <ul|ol><li>...</li></ul|ol>
    $this->bbcode_table["/\[list=(1|a)\](.*?)\[\/list\]/is"] = function ($match) {
      if ($match[1] == '1') {
        $list_type = '<ol>';
      } else if ($match[1] == 'a') {
        $list_type = '<ol style="list-style-type: lower-alpha">';
      } else {
        $list_type = '<ol>';
      }

      $match[2] = preg_replace_callback("/\[\*\]([^\[\*\]]*)/is", function ($submatch) {
        return "<li>" . preg_replace("/[\n\r?]$/", "", $submatch[1]) . "</li>";
      }, $match[2]);

      return $list_type . preg_replace("/[\n\r?]/", "", $match[2]) . "</ol>";
    };


    // Replace [youtube]...[/youtube] with <iframe src="..."></iframe>
    $this->bbcode_table["/\[youtube\](?:http?:\/\/)?(?:www\.)?youtu(?:\.be\/|be\.com\/watch\?v=)([A-Z0-9\-_]+)(?:&(.*?))?\[\/youtube\]/i"] = function ($match) {
      return "<iframe class=\"youtube-player\" type=\"text/html\" width=\"640\" height=\"385\" src=\"http://www.youtube.com/embed/$match[1]\" frameborder=\"0\"></iframe>";
    };
  }
  
  public function toHTML ($str, $escapeHTML=false, $nr2br=false) {
    if (!$str) { 
      return "";
    }
    
    if ($escapeHTML) {
      $str = htmlspecialchars($str);
    }

    foreach($this->bbcode_table as $key => $val) {
      $str = preg_replace_callback($key, $val, $str);
    }

    if ($nr2br) {
      $str = preg_replace_callback("/\n\r?/", function ($match) { return "<br/>"; }, $str);
    }
    
    return $str;
  }
}
?>