plugins/markdown/markdown.php

   1 <?php
   2
   3 /**
   4  * Plugin Markdown.
   5  *
   6  * Shaare's descriptions are parsed with Markdown.
   7  */
   8
   9 require_once 'Parsedown.php';
  10
  11 /*
  12  * If this tag is used on a shaare, the description won't be processed by Parsedown.
  13  */
  14 define('NO_MD_TAG', 'nomarkdown');
  15
  16 /**
  17  * Parse linklist descriptions.
  18  *
  19  * @param array $data linklist data.
  20  *
  21  * @return mixed linklist data parsed in markdown (and converted to HTML).
  22  */
  23 function hook_markdown_render_linklist($data)
  24 {
  25     foreach ($data['links'] as &$value) {
  26         if (!empty($value['tags']) && noMarkdownTag($value['tags'])) {
  27             $value['taglist'] = stripNoMarkdownTag($value['taglist']);
  28             continue;
  29         }
  30         $value['description'] = process_markdown($value['description']);
  31     }
  32     return $data;
  33 }
  34
  35 /**
  36  * Parse feed linklist descriptions.
  37  *
  38  * @param array $data linklist data.
  39  *
  40  * @return mixed linklist data parsed in markdown (and converted to HTML).
  41  */
  42 function hook_markdown_render_feed($data)
  43 {
  44     foreach ($data['links'] as &$value) {
  45         if (!empty($value['tags']) && noMarkdownTag($value['tags'])) {
  46             $value['tags'] = stripNoMarkdownTag($value['tags']);
  47             continue;
  48         }
  49         $value['description'] = process_markdown($value['description']);
  50     }
  51
  52     return $data;
  53 }
  54
  55 /**
  56  * Parse daily descriptions.
  57  *
  58  * @param array $data daily data.
  59  *
  60  * @return mixed daily data parsed in markdown (and converted to HTML).
  61  */
  62 function hook_markdown_render_daily($data)
  63 {
  64     // Manipulate columns data
  65     foreach ($data['cols'] as &$value) {
  66         foreach ($value as &$value2) {
  67             if (!empty($value2['tags']) && noMarkdownTag($value2['tags'])) {
  68                 continue;
  69             }
  70             $value2['formatedDescription'] = process_markdown($value2['formatedDescription']);
  71         }
  72     }
  73
  74     return $data;
  75 }
  76
  77 /**
  78  * Check if noMarkdown is set in tags.
  79  *
  80  * @param string $tags tag list
  81  *
  82  * @return bool true if markdown should be disabled on this link.
  83  */
  84 function noMarkdownTag($tags)
  85 {
  86     return strpos($tags, NO_MD_TAG) !== false;
  87 }
  88
  89 /**
  90  * Remove the no-markdown meta tag so it won't be displayed.
  91  *
  92  * @param string $tags Tag list.
  93  *
  94  * @return string tag list without no markdown tag.
  95  */
  96 function stripNoMarkdownTag($tags)
  97 {
  98     unset($tags[array_search(NO_MD_TAG, $tags)]);
  99     return array_values($tags);
 100 }
 101
 102 /**
 103  * When link list is displayed, include markdown CSS.
 104  *
 105  * @param array $data includes data.
 106  *
 107  * @return mixed - includes data with markdown CSS file added.
 108  */
 109 function hook_markdown_render_includes($data)
 110 {
 111     if ($data['_PAGE_'] == Router::$PAGE_LINKLIST
 112         || $data['_PAGE_'] == Router::$PAGE_DAILY
 113         || $data['_PAGE_'] == Router::$PAGE_EDITLINK
 114     ) {
 115
 116         $data['css_files'][] = PluginManager::$PLUGINS_PATH . '/markdown/markdown.css';
 117     }
 118
 119     return $data;
 120 }
 121
 122 /**
 123  * Hook render_editlink.
 124  * Adds an help link to markdown syntax.
 125  *
 126  * @param array $data data passed to plugin
 127  *
 128  * @return array altered $data.
 129  */
 130 function hook_markdown_render_editlink($data)
 131 {
 132     // Load help HTML into a string
 133     $data['edit_link_plugin'][] = file_get_contents(PluginManager::$PLUGINS_PATH .'/markdown/help.html');
 134
 135     // Add no markdown 'meta-tag' in tag list if it was never used, for autocompletion.
 136     if (! in_array(NO_MD_TAG, $data['tags'])) {
 137         $data['tags'][NO_MD_TAG] = 0;
 138     }
 139
 140     return $data;
 141 }
 142
 143
 144 /**
 145  * Remove HTML links auto generated by Shaarli core system.
 146  * Keeps HREF attributes.
 147  *
 148  * @param string $description input description text.
 149  *
 150  * @return string $description without HTML links.
 151  */
 152 function reverse_text2clickable($description)
 153 {
 154     return preg_replace('!<a +href="([^ ]*)">[^ ]+</a>!m', '$1', $description);
 155 }
 156
 157 /**
 158  * Remove <br> tag to let markdown handle it.
 159  *
 160  * @param string $description input description text.
 161  *
 162  * @return string $description without <br> tags.
 163  */
 164 function reverse_nl2br($description)
 165 {
 166     return preg_replace('!<br */?>!im', '', $description);
 167 }
 168
 169 /**
 170  * Remove HTML spaces '&nbsp;' auto generated by Shaarli core system.
 171  *
 172  * @param string $description input description text.
 173  *
 174  * @return string $description without HTML links.
 175  */
 176 function reverse_space2nbsp($description)
 177 {
 178     return preg_replace('/(^| )&nbsp;/m', '$1 ', $description);
 179 }
 180
 181 /**
 182  * Remove dangerous HTML tags (tags, iframe, etc.).
 183  * Doesn't affect <code> content (already escaped by Parsedown).
 184  *
 185  * @param string $description input description text.
 186  *
 187  * @return string given string escaped.
 188  */
 189 function sanitize_html($description)
 190 {
 191     $escapeTags = array(
 192         'script',
 193         'style',
 194         'link',
 195         'iframe',
 196         'frameset',
 197         'frame',
 198     );
 199     foreach ($escapeTags as $tag) {
 200         $description = preg_replace_callback(
 201             '#<\s*'. $tag .'[^>]*>(.*</\s*'. $tag .'[^>]*>)?#is',
 202             function ($match) { return escape($match[0]); },
 203             $description);
 204     }
 205     $description = preg_replace(
 206         '#(<[^>]+)on[a-z]*="[^"]*"#is',
 207         '$1',
 208         $description);
 209     return $description;
 210 }
 211
 212 /**
 213  * Render shaare contents through Markdown parser.
 214  *   1. Remove HTML generated by Shaarli core.
 215  *   2. Reverse the escape function.
 216  *   3. Generate markdown descriptions.
 217  *   4. Sanitize sensible HTML tags for security.
 218  *   5. Wrap description in 'markdown' CSS class.
 219  *
 220  * @param string $description input description text.
 221  *
 222  * @return string HTML processed $description.
 223  */
 224 function process_markdown($description)
 225 {
 226     $parsedown = new Parsedown();
 227
 228     $processedDescription = $description;
 229     $processedDescription = reverse_text2clickable($processedDescription);
 230     $processedDescription = reverse_nl2br($processedDescription);
 231     $processedDescription = reverse_space2nbsp($processedDescription);
 232     $processedDescription = unescape($processedDescription);
 233     $processedDescription = $parsedown
 234         ->setMarkupEscaped(false)
 235         ->setBreaksEnabled(true)
 236         ->text($processedDescription);
 237     $processedDescription = sanitize_html($processedDescription);
 238
 239     if(!empty($processedDescription)){
 240         $processedDescription = '<div class="markdown">'. $processedDescription . '</div>';
 241     }
 242
 243     return $processedDescription;
 244 }