1. <?php
2.  
3. /**
4.  * @file BBCodeConverter.php
5.  * @brief This file contains the BBCodeConverter class.
6.  * @details
7.  * @author Filippo F. Fadda
8.  */
9.  
10.  
11.  
12. /**
13.  * @brief A rudimental converter that takes as input a BBCode formatted text and converts it to Markdown.
14.  */
15. class BBCodeConverter extends Converter {
16.  
17.  
18.   /**
19.    * @brief Removes BBCode size.
20.    */
21.   protected function removeSize() {
22.  
23.     $this->text = preg_replace_callback('%\[size=\d*\]([\W\D\w\s]*?)\[/size\]%iu',
24.  
25.       function ($matches) {
26.         return $matches[1];
27.       },
28.  
29.       $this->text
30.     );
31.  
32.   }
33.  
34.  
35.   /**
36.    * @brief Removes BBCode center.
37.    */
38.   protected function removeCenter() {
39.  
40.     $this->text = preg_replace_callback('%\[center\]([\W\D\w\s]*?)\[/center\]%iu',
41.  
42.       function ($matches) {
43.         return $matches[1];
44.       },
45.  
46.       $this->text
47.     );
48.  
49.   }
50.  
51.  
52.   /**
53.    * @brief Replaces BBCode bold.
54.    */
55.   protected function replaceBold() {
56.  
57.     $this->text = preg_replace_callback('%\[b\]([\W\D\w\s]*?)\[/b\]%iu',
58.  
59.       function ($matches) {
60.         return "**".trim($matches[1], " ")."**";
61.       },
62.  
63.       $this->text
64.     );
65.  
66.   }
67.  
68.  
69.   /**
70.    * @brief Replaces BBCode italic.
71.    */
72.   protected function replaceItalic() {
73.  
74.     $this->text = preg_replace_callback('%\[i\]([\W\D\w\s]*?)\[/i\]%iu',
75.  
76.       function ($matches) {
77.         return "*".trim($matches[1], " ")."*";
78.       },
79.  
80.       $this->text
81.     );
82.  
83.   }
84.  
85.  
86.   /**
87.    * @brief Replaces BBCode underline. Hoedown support underline.
88.    */
89.   protected function replaceUnderline() {
90.  
91.     $this->text = preg_replace_callback('%\[u\]([\W\D\w\s]*?)\[/u\]%iu',
92.  
93.       function ($matches) {
94.         return "_".trim($matches[1], " ")."_";
95.       },
96.  
97.       $this->text
98.     );
99.    
100.   }
101.  
102.  
103.   /**
104.    * @brief Replaces BBCode strikethrough.
105.    */
106.   protected function replaceStrikethrough() {
107.  
108.     $this->text = preg_replace_callback('%\[s\]([\W\D\w\s]*?)\[/s\]%iu',
109.  
110.       function ($matches) {
111.         return "~~".trim($matches[1], " ")."~~";
112.       },
113.  
114.       $this->text
115.     );
116.  
117.   }
118.  
119.  
120.   /**
121.    * @brief Replaces BBCode lists.
122.    */
123.   protected function replaceLists() {
124.  
125.     $this->text = preg_replace_callback('%\[list(?P<type>=1)?\](?P<items>[\W\D\w\s]*?)\[/list\]%iu',
126.  
127.       function ($matches) {
128.         $buffer = "";
129.  
130.         $list = preg_replace('/\s*$|^\s*/mu', '', $matches['items']);
131.         if (is_null($list))
132.           throw new \RuntimeException(sprintf("Text identified by '%d' has malformed BBCode lists", $this->id));
133.  
134.         $items = preg_split('/\[\*\]/u', $list);
135.  
136.         $counter = count($items);
137.  
138.         if (isset($matches['type']) && $matches['type'] == '=1') { // ordered list
139.           // We start from 1 to discard the first string, in fact, it's empty.
140.          for ($i = 1; $i < $counter; $i++)
141.            if (!empty($items[$i]))
142.              $buffer .= (string)($i).'. '.trim($items[$i]).PHP_EOL;
143.        }
144.        else { // unordered list
145.          // We start from 1 to discard the first string, in fact, it's empty.
146.           for ($i = 1; $i < $counter; $i++)
147.             if (!empty($items[$i]))
148.               $buffer .= '- '.trim($items[$i]).PHP_EOL;
149.         }
150.  
151.         // We need a like break above the list and another one below.
152.         if (!empty($buffer))
153.           $buffer = PHP_EOL.$buffer.PHP_EOL;
154.  
155.         return $buffer;
156.       },
157.  
158.       $this->text
159.     );
160.  
161.   }
162.  
163.  
164.   /**
165.    * @brief Replaces BBCode urls.
166.    */
167.   protected function replaceUrls() {
168.    
169.     $this->text = preg_replace_callback('%\[url\s*=\s*("(?:[^"]*")|\A[^\']*\Z|(?:[^\'">\]\s]+))\s*(?:[^]\s]*)\]([\W\D\w\s]*?)\[/url\]%iu',
170.  
171.       function ($matches) {
172.         if (isset($matches[1]) && isset($matches[2]))
173.           return "[".$matches[2]."](".$matches[1].")";
174.         else
175.           throw new \RuntimeException(sprintf("Text identified by '%d' has malformed BBCode urls", $this->id));
176.       },
177.  
178.       $this->text
179.     );
180.  
181.   }
182.  
183.  
184.   /**
185.    * @brief Replaces BBCode images.
186.    */
187.   protected function replaceImages() {
188.  
189.     $this->text = preg_replace_callback('%\[img\s*\]\s*("(?:[^"]*")|\A[^\']*\Z|(?:[^\'">\]\s]+))\s*(?:[^]\s]*)\[/img\]%iu',
190.  
191.       function ($matches) {
192.         if (isset($matches[1]))
193.           return PHP_EOL."![]"."(".$matches[1].")".PHP_EOL;
194.         else
195.           throw new \RuntimeException(sprintf("Text identified by '%d' have malformed BBCode images", $this->id));
196.       },
197.  
198.       $this->text
199.     );
200.  
201.   }
202.  
203.  
204.   /**
205.    * @brief Replaces BBCode quotes.
206.    * @details Thanks to Casimir et Hippolyte for helping me with this regex.
207.    */
208.   protected function replaceQuotes() {
209.     // Removes the inner quotes, leaving just one level.
210.     $this->text = preg_replace('~\G(?<!^)(?>(\[quote\b[^]]*](?>[^[]++|\[(?!/?quote)|(?1))*\[/quote])|(?<!\[)(?>[^[]++|\[(?!/?quote))+\K)|\[quote\b[^]]*]\K~', '', $this->text);
211.  
212.     // Replaces all the remaining quotes with '> ' characters.
213.     $this->text = preg_replace_callback('%\[quote\b[^]]*\]((?>[^[]++|\[(?!/?quote))*)\[/quote\]%i',
214.  
215.       function($matches) {
216.         $quote = preg_replace('/^\s*/mu', '', trim($matches[1]));
217.         return "> ".$quote.PHP_EOL.PHP_EOL;
218.       },
219.  
220.       $this->text
221.     );
222.   }
223.  
224.  
225.   /**
226.    * @brief Replaces BBCode snippets.
227.    */
228.   protected function replaceSnippets() {
229.  
230.     $this->text = preg_replace_callback('%\[code\s*=?(?P<language>\w*)\](?P<snippet>[\W\D\w\s]*?)\[\/code\]%iu',
231.  
232.       function ($matches) {
233.         if (isset($matches['snippet'])) {
234.           $language = strtolower($matches['language']);
235.  
236.           if ($language == 'html4strict' or $language == 'div')
237.             $language = 'html';
238.           elseif ($language == 'shell' or $language == 'dos' or $language == 'batch')
239.             $language = 'sh';
240.           elseif ($language == 'xul' or $language == 'wpf')
241.             $language = 'xml';
242.           elseif ($language == 'asm')
243.             $language = 'nasm';
244.           elseif ($language == 'vb' or $language == 'visualbasic' or $language == 'vba')
245.             $language = 'vb.net';
246.           elseif ($language == 'asp')
247.             $language = 'aspx-vb';
248.           elseif ($language == 'xaml')
249.             $language = 'xml';
250.           elseif ($language == 'cplusplus')
251.             $language = 'cpp';
252.           elseif ($language == 'txt' or $language == 'gettext')
253.             $language = 'text';
254.           elseif ($language == 'basic')
255.             $language = 'cbmbas';
256.           elseif ($language == 'lisp')
257.             $language = 'clojure';
258.           elseif ($language == 'aspnet')
259.             $language = 'aspx-vb';
260.  
261.           return PHP_EOL."```".$language.PHP_EOL.trim($matches['snippet']).PHP_EOL."```".PHP_EOL;
262.         }
263.         else
264.           throw new \RuntimeException(sprintf("Text identified by '%d' has malformed BBCode snippet.", $this->id));
265.       },
266.  
267.       $this->text
268.     );
269.  
270.   }
271.  
272.  
273.   /**
274.    * @brief Converts the provided BBCode text to an equivalent Markdown text.
275.    */
276.   public function toMarkdown() {
277.     $this->removeCenter();
278.     $this->removeSize();
279.     $this->replaceBold();
280.     $this->replaceItalic();
281.     $this->replaceUnderline();
282.     $this->replaceStrikethrough();
283.     $this->replaceLists();
284.     $this->replaceUrls();
285.     $this->replaceImages();
286.     $this->replaceQuotes();
287.     $this->replaceSnippets();
288.  
289.     return $this->text;
290.   }
291.  
292. }