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