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  * Parse linklist descriptions.
  13  *
  14  * @param array $data linklist data.
  15  *
  16  * @return mixed linklist data parsed in markdown (and converted to HTML).
  17  */
  18 function hook_markdown_render_linklist($data)
  19 {
  20     foreach ($data['links'] as &$value) {
  21         $value['description'] = process_markdown($value['description']);
  22     }
  23
  24     return $data;
  25 }
  26
  27 /**
  28  * Parse daily descriptions.
  29  *
  30  * @param array $data daily data.
  31  *
  32  * @return mixed daily data parsed in markdown (and converted to HTML).
  33  */
  34 function hook_markdown_render_daily($data)
  35 {
  36     // Manipulate columns data
  37     foreach ($data['cols'] as &$value) {
  38         foreach ($value as &$value2) {
  39             $value2['formatedDescription'] = process_markdown($value2['formatedDescription']);
  40         }
  41     }
  42
  43     return $data;
  44 }
  45
  46 /**
  47  * When link list is displayed, include markdown CSS.
  48  *
  49  * @param array $data includes data.
  50  *
  51  * @return mixed - includes data with markdown CSS file added.
  52  */
  53 function hook_markdown_render_includes($data)
  54 {
  55     if ($data['_PAGE_'] == Router::$PAGE_LINKLIST
  56         || $data['_PAGE_'] == Router::$PAGE_DAILY
  57         || $data['_PAGE_'] == Router::$PAGE_EDITLINK
  58     ) {
  59
  60         $data['css_files'][] = PluginManager::$PLUGINS_PATH . '/markdown/markdown.css';
  61     }
  62
  63     return $data;
  64 }
  65
  66 /**
  67  * Hook render_editlink.
  68  * Adds an help link to markdown syntax.
  69  *
  70  * @param array $data data passed to plugin
  71  *
  72  * @return array altered $data.
  73  */
  74 function hook_markdown_render_editlink($data)
  75 {
  76     // Load help HTML into a string
  77     $data['edit_link_plugin'][] = file_get_contents(PluginManager::$PLUGINS_PATH .'/markdown/help.html');
  78     return $data;
  79 }
  80
  81
  82 /**
  83  * Remove HTML links auto generated by Shaarli core system.
  84  * Keeps HREF attributes.
  85  *
  86  * @param string $description input description text.
  87  *
  88  * @return string $description without HTML links.
  89  */
  90 function reverse_text2clickable($description)
  91 {
  92     return preg_replace('!<a +href="([^ ]*)">[^ ]+</a>!m', '$1', $description);
  93 }
  94
  95 /**
  96  * Remove <br> tag to let markdown handle it.
  97  *
  98  * @param string $description input description text.
  99  *
 100  * @return string $description without <br> tags.
 101  */
 102 function reverse_nl2br($description)
 103 {
 104     return preg_replace('!<br */?>!im', '', $description);
 105 }
 106
 107 /**
 108  * Remove HTML spaces '&nbsp;' auto generated by Shaarli core system.
 109  *
 110  * @param string $description input description text.
 111  *
 112  * @return string $description without HTML links.
 113  */
 114 function reverse_space2nbsp($description)
 115 {
 116     return preg_replace('/(^| )&nbsp;/m', '$1 ', $description);
 117 }
 118
 119 /**
 120  * Remove dangerous HTML tags (tags, iframe, etc.).
 121  * Doesn't affect <code> content (already escaped by Parsedown).
 122  *
 123  * @param string $description input description text.
 124  *
 125  * @return string given string escaped.
 126  */
 127 function sanitize_html($description)
 128 {
 129     $escapeTags = array(
 130         'script',
 131         'style',
 132         'link',
 133         'iframe',
 134         'frameset',
 135         'frame',
 136     );
 137     foreach ($escapeTags as $tag) {
 138         $description = preg_replace_callback(
 139             '#<\s*'. $tag .'[^>]*>(.*</\s*'. $tag .'[^>]*>)?#is',
 140             function ($match) { return escape($match[0]); },
 141             $description);
 142     }
 143     $description = preg_replace(
 144         '#(<[^>]+)on[a-z]*="[^"]*"#is',
 145         '$1',
 146         $description);
 147     return $description;
 148 }
 149
 150 /**
 151  * Render shaare contents through Markdown parser.
 152  *   1. Remove HTML generated by Shaarli core.
 153  *   2. Reverse the escape function.
 154  *   3. Generate markdown descriptions.
 155  *   4. Sanitize sensible HTML tags for security.
 156  *   5. Wrap description in 'markdown' CSS class.
 157  *
 158  * @param string $description input description text.
 159  *
 160  * @return string HTML processed $description.
 161  */
 162 function process_markdown($description)
 163 {
 164     $parsedown = new Parsedown();
 165
 166     $processedDescription = $description;
 167     $processedDescription = reverse_text2clickable($processedDescription);
 168     $processedDescription = reverse_nl2br($processedDescription);
 169     $processedDescription = reverse_space2nbsp($processedDescription);
 170     $processedDescription = unescape($processedDescription);
 171     $processedDescription = $parsedown
 172         ->setMarkupEscaped(false)
 173         ->setBreaksEnabled(true)
 174         ->text($processedDescription);
 175     $processedDescription = sanitize_html($processedDescription);
 176     $processedDescription = '<div class="markdown">'. $processedDescription . '</div>';
 177
 178     return $processedDescription;
 179 }