aleph1.co.uk Git - yaffs-website/blob - vendor/cebe/markdown/block/HtmlTrait.php

   1 <?php
   2 /**
   3  * @copyright Copyright (c) 2014 Carsten Brandt
   4  * @license https://github.com/cebe/markdown/blob/master/LICENSE
   5  * @link https://github.com/cebe/markdown#readme
   6  */
   7
   8 namespace cebe\markdown\block;
   9
  10 /**
  11  * Adds inline and block HTML support
  12  */
  13 trait HtmlTrait
  14 {
  15         /**
  16          * @var array HTML elements considered as inline elements.
  17          * @see http://www.w3.org/wiki/HTML/Elements#Text-level_semantics
  18          */
  19         protected $inlineHtmlElements = [
  20                 'a', 'abbr', 'acronym',
  21                 'b', 'basefont', 'bdo', 'big', 'br', 'button', 'blink',
  22                 'cite', 'code',
  23                 'del', 'dfn',
  24                 'em',
  25                 'font',
  26                 'i', 'img', 'ins', 'input', 'iframe',
  27                 'kbd',
  28                 'label', 'listing',
  29                 'map', 'mark',
  30                 'nobr',
  31                 'object',
  32                 'q',
  33                 'rp', 'rt', 'ruby',
  34                 's', 'samp', 'script', 'select', 'small', 'spacer', 'span', 'strong', 'sub', 'sup',
  35                 'tt', 'var',
  36                 'u',
  37                 'wbr',
  38                 'time',
  39         ];
  40         /**
  41          * @var array HTML elements known to be self-closing.
  42          */
  43         protected $selfClosingHtmlElements = [
  44                 'br', 'hr', 'img', 'input', 'nobr',
  45         ];
  46
  47         /**
  48          * identify a line as the beginning of a HTML block.
  49          */
  50         protected function identifyHtml($line, $lines, $current)
  51         {
  52                 if ($line[0] !== '<' || isset($line[1]) && $line[1] == ' ') {
  53                         return false; // no html tag
  54                 }
  55
  56                 if (strncmp($line, '<!--', 4) === 0) {
  57                         return true; // a html comment
  58                 }
  59
  60                 $gtPos = strpos($lines[$current], '>');
  61                 $spacePos = strpos($lines[$current], ' ');
  62                 if ($gtPos === false && $spacePos === false) {
  63                         return false; // no html tag
  64                 } elseif ($spacePos === false) {
  65                         $tag = rtrim(substr($line, 1, $gtPos - 1), '/');
  66                 } else {
  67                         $tag = rtrim(substr($line, 1, min($gtPos, $spacePos) - 1), '/');
  68                 }
  69
  70                 if (!ctype_alnum($tag) || in_array(strtolower($tag), $this->inlineHtmlElements)) {
  71                         return false; // no html tag or inline html tag
  72                 }
  73                 return true;
  74         }
  75
  76         /**
  77          * Consume lines for an HTML block
  78          */
  79         protected function consumeHtml($lines, $current)
  80         {
  81                 $content = [];
  82                 if (strncmp($lines[$current], '<!--', 4) === 0) { // html comment
  83                         for ($i = $current, $count = count($lines); $i < $count; $i++) {
  84                                 $line = $lines[$i];
  85                                 $content[] = $line;
  86                                 if (strpos($line, '-->') !== false) {
  87                                         break;
  88                                 }
  89                         }
  90                 } else {
  91                         $tag = rtrim(substr($lines[$current], 1, min(strpos($lines[$current], '>'), strpos($lines[$current] . ' ', ' ')) - 1), '/');
  92                         $level = 0;
  93                         if (in_array($tag, $this->selfClosingHtmlElements)) {
  94                                 $level--;
  95                         }
  96                         for ($i = $current, $count = count($lines); $i < $count; $i++) {
  97                                 $line = $lines[$i];
  98                                 $content[] = $line;
  99                                 $level += substr_count($line, "<$tag") - substr_count($line, "</$tag>");
 100                                 if ($level <= 0) {
 101                                         break;
 102                                 }
 103                         }
 104                 }
 105                 $block = [
 106                         'html',
 107                         'content' => implode("\n", $content),
 108                 ];
 109                 return [$block, $i];
 110         }
 111
 112         /**
 113          * Renders an HTML block
 114          */
 115         protected function renderHtml($block)
 116         {
 117                 return $block['content'] . "\n";
 118         }
 119
 120         /**
 121          * Parses an & or a html entity definition.
 122          * @marker &
 123          */
 124         protected function parseEntity($text)
 125         {
 126                 // html entities e.g. &copy; &#169; &#x00A9;
 127                 if (preg_match('/^&#?[\w\d]+;/', $text, $matches)) {
 128                         return [['inlineHtml', $matches[0]], strlen($matches[0])];
 129                 } else {
 130                         return [['text', '&amp;'], 1];
 131                 }
 132         }
 133
 134         /**
 135          * renders a html entity.
 136          */
 137         protected function renderInlineHtml($block)
 138         {
 139                 return $block[1];
 140         }
 141
 142         /**
 143          * Parses inline HTML.
 144          * @marker <
 145          */
 146         protected function parseInlineHtml($text)
 147         {
 148                 if (strpos($text, '>') !== false) {
 149                         if (preg_match('~^</?(\w+\d?)( .*?)?>~', $text, $matches)) {
 150                                 // HTML tags
 151                                 return [['inlineHtml', $matches[0]], strlen($matches[0])];
 152                         } elseif (preg_match('~^<!--.*?-->~', $text, $matches)) {
 153                                 // HTML comments
 154                                 return [['inlineHtml', $matches[0]], strlen($matches[0])];
 155                         }
 156                 }
 157                 return [['text', '&lt;'], 1];
 158         }
 159
 160         /**
 161          * Escapes `>` characters.
 162          * @marker >
 163          */
 164         protected function parseGt($text)
 165         {
 166                 return [['text', '&gt;'], 1];
 167         }
 168 }