$1',$url);
;
}
global $escape_sequence_map;
function parse($text)
{
# removes UTF-8 BOM and marker characters
$text = preg_replace('{^\xEF\xBB\xBF|\x1A}', '', $text);
# removes \r characters
$text = str_replace("\r\n", "\n", $text);
$text = str_replace("\r", "\n", $text);
# replaces tabs with spaces
$text = str_replace("\t", ' ', $text);
# encodes escape sequences
if (strpos($text, '\\') !== FALSE)
{
$escape_sequences = array('\\\\', '\`', '\*', '\_', '\{', '\}', '\[', '\]', '\(', '\)', '\>', '\#', '\+', '\-', '\.', '\!');
foreach ($escape_sequences as $index => $escape_sequence)
{
if (strpos($text, $escape_sequence) !== FALSE)
{
$code = "\x1A".'\\'.$index.';';
$text = str_replace($escape_sequence, $code, $text);
$escape_sequence_map[$code] = $escape_sequence;
}
}
}
# ~
$text = preg_replace('/\n\s*\n/', "\n\n", $text);
$text = trim($text, "\n");
$lines = explode("\n", $text);
$text = parse_block_elements($lines);
# decodes escape sequences
if (!empty($escape_sequence_map)){
foreach ($escape_sequence_map as $code => $escape_sequence)
{
$text = str_replace($code, $escape_sequence[1], $text);
}
}
$text = rtrim($text, "\n");
return $text;
}
function parse_block_elements(array $lines, $context = '')
{
$elements = array();
$element = array('type' => '',);
foreach ($lines as $line)
{
# markup (open)
if ($element['type'] === 'markup' and ! isset($element['closed']))
{
if (preg_match('{<'.$element['subtype'].'>$}', $line)) # opening tag
{
$element['depth']++;
}
if (preg_match('{$}', $line)) # closing tag
{
$element['depth'] > 0
? $element['depth']--
: $element['closed'] = true;
}
$element['text'] .= "\n".$line;
continue;
}
# *
if ($line === '')
{
$element['interrupted'] = true;
continue;
}
# blockquote (existing)
if ($element['type'] === 'blockquote' and ! isset($element['interrupted']))
{
$line = preg_replace('/^[ ]*>[ ]?/', '', $line);
$element['lines'] []= $line;
continue;
}
# list (existing)
if ($element['type'] === 'li')
{
if (preg_match('/^([ ]{0,3})(\d+[.]|[*+-])[ ](.*)/', $line, $matches))
{
if ($element['indentation'] !== $matches[1])
{
$element['lines'] []= $line;
}
else
{
unset($element['last']);
$elements []= $element;
$element = array(
'type' => 'li',
'indentation' => $matches[1],
'last' => true,
'lines' => array(
preg_replace('/^[ ]{0,4}/', '', $matches[3]),
),
);
}
continue;
}
if (isset($element['interrupted']))
{
if ($line[0] === ' ')
{
$element['lines'] []= '';
$line = preg_replace('/^[ ]{0,4}/', '', $line);
$element['lines'] []= $line;
continue;
}
}
else
{
$line = preg_replace('/^[ ]{0,4}/', '', $line);
$element['lines'] []= $line;
continue;
}
}
# paragraph
if ($line[0] >= 'a' or $line[0] >= 'A' and $line[0] <= 'Z')
{
goto paragraph;
}
# code block
if ($line[0] === ' ' and preg_match('/^[ ]{4}(.*)/', $line, $matches))
{
if (trim($line) === ''){continue;}
if ($element['type'] === 'code')
{
if (isset($element['interrupted']))
{
$element['text'] .= "\n";
unset ($element['interrupted']);
}
$element['text'] .= "\n".$matches[1];
}
else
{
$elements []= $element;
$element = array(
'type' => 'code',
'text' => $matches[1],
);
}
continue;
}
# setext heading (---)
if ($line[0] === '-' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[-]+[ ]*$/', $line))
{
$element['type'] = 'h.';
$element['level'] = 2;
continue;
}
# atx heading (#)
if ($line[0] === '#' and preg_match('/^(#{1,6})[ ]*(.+?)[ ]*#*$/', $line, $matches))
{
$elements []= $element;
$level = strlen($matches[1]);
$element = array(
'type' => 'h.',
'text' => $matches[2],
'level' => $level,
);
continue;
}
# setext heading (===)
if ($line[0] === '=' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[=]+[ ]*$/', $line))
{
$element['type'] = 'h.';
$element['level'] = 1;
continue;
}
$deindented_line = $line[0] !== ' ' ? $line : ltrim($line);
if ($deindented_line === ''){continue;}
# reference
if ($deindented_line[0] === '[' and preg_match('/^\[(.+?)\]:[ ]*([^ ]+)/', $deindented_line, $matches))
{
$label = strtolower($matches[1]);
$url = trim($matches[2], '<>');
$reference_map[$label] = $url;
continue;
}
# blockquote
if ($deindented_line[0] === '>' and preg_match('/^>[ ]?(.*)/', $deindented_line, $matches))
{
if ($element['type'] === 'blockquote')
{
if (isset($element['interrupted']))
{
$element['lines'] []= '';
unset($element['interrupted']);
}
$element['lines'] []= $matches[1];
}
else
{
$elements []= $element;
$element = array(
'type' => 'blockquote',
'lines' => array(
$matches[1],
),
);
}
continue;
}
# markup
if ($deindented_line[0] === '<')
{
# self-closing tag
if (preg_match('{^<.+?/>$}', $deindented_line))
{
$elements []= $element;
$element = array(
'type' => '',
'text' => $deindented_line,
);
continue;
}
# opening tag
if (preg_match('{^<(\w+)(?:[ ].*?)?>}', $deindented_line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'markup',
'subtype' => strtolower($matches[1]),
'text' => $deindented_line,
'depth' => 0,
);
preg_match('{\s*$}', $deindented_line) and $element['closed'] = true;
continue;
}
}
# horizontal rule
if (preg_match('/^([-*_])([ ]{0,2}\1){2,}[ ]*$/', $deindented_line))
{
$elements []= $element;
$element = array('type' => 'hr',);
continue;
}
# list item
if (preg_match('/^([ ]*)(\d+[.]|[*+-])[ ](.*)/', $line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'li',
'ordered' => isset($matches[2][1]),
'indentation' => $matches[1],
'last' => true,
'lines' => array(
preg_replace('/^[ ]{0,4}/', '', $matches[3]),
),
);
continue;
}
paragraph:
if ($element['type'] === 'p')
{
if (isset($element['interrupted']))
{
$elements []= $element;
$element['text'] = $line;
unset($element['interrupted']);
}
else {$element['text'] .= "\n".$line;}
}
else
{
$elements []= $element;
$element = array(
'type' => 'p',
'text' => $line,
);
}
}
$elements []= $element;
array_shift($elements);
$markup = '';
foreach ($elements as $index => $element)
{
switch ($element['type'])
{
case 'p':
$text = parse_span_elements($element['text']);
$text = preg_replace('/[ ]{2}\n/', '
'."\n", $text);
if ($context === 'li' and $index === 0)
{
if (isset($element['interrupted'])) { $markup .= "\n".''.$text.'
'."\n";}
else {$markup .= $text;}
}
else{$markup .= ''.$text.'
'."\n";}
break;
case 'blockquote':
$text =parse_block_elements($element['lines']);
$markup .= ''."\n".$text.'
'."\n";
break;
case 'code':
$text = htmlentities($element['text'], ENT_NOQUOTES);
strpos($text, "\x1A\\") !== FALSE and $text = strtr($text, $escape_sequence_map);
$markup .= ''.$text.'
'."\n";
break;
case 'h.':
$text = parse_span_elements($element['text']);
$markup .= ''.$text.''."\n";
break;
case 'hr':
$markup .= '
'."\n";
break;
case 'li':
if (isset($element['ordered'])) # first
{
$list_type = $element['ordered'] ? 'ol' : 'ul';
$markup .= '<'.$list_type.'>'."\n";
}
if (isset($element['interrupted']) and ! isset($element['last']))
{
$element['lines'] []= '';
}
$text = parse_block_elements($element['lines'], 'li');
$markup .= ''.$text.''."\n";
isset($element['last']) and $markup .= ''."\n";
break;
default:
$markup .= $element['text']."\n";
}
}
return $markup;
}
function parse_span_elements($text)
{
$map = array();
$index = 0;
# code span
if (strpos($text, '`') !== FALSE and preg_match_all('/`(.+?)`/', $text, $matches, PREG_SET_ORDER))
{
foreach ($matches as $matches)
{
$element_text = $matches[1];
$element_text = htmlentities($element_text, ENT_NOQUOTES);
# decodes escape sequences
$escape_sequence_map
and strpos($element_text, "\x1A") !== FALSE
and $element_text = strtr($element_text, $escape_sequence_map);
# composes element
$element = ''.$element_text.'';
# encodes element
$code = "\x1A".'$'.$index;
$text = str_replace($matches[0], $code, $text);
$map[$code] = $element;
$index ++;
}
}
# inline link or image
if (strpos($text, '](') !== FALSE and preg_match_all('/(!?)(\[((?:[^\[\]]|(?2))*)\])\((.*?)\)/', $text, $matches, PREG_SET_ORDER)) # inline
{
foreach ($matches as $matches)
{
$url = $matches[4];
strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&', $url);
if ($matches[1]) # image
{
$element = '!['.$matches[3].']('.$url.')
';
}
else
{
$element_text =parse_span_elements($matches[3]);
$element = ''.$element_text.'';
}
$code = "\x1A".'$'.$index;
$text = str_replace($matches[0], $code, $text);
$map[$code] = $element;
$index ++;
}
}
# reference link or image
if (strpos($text, '[') !== FALSE and preg_match_all('/(!?)\[(.+?)\](?:\n?[ ]?\[(.*?)\])?/ms', $text, $matches, PREG_SET_ORDER))
{
foreach ($matches as $matches)
{
$link_definition = isset($matches[3]) && $matches[3]
? $matches[3]
: $matches[2]; # implicit
$link_definition = strtolower($link_definition);
if (isset($reference_map[$link_definition]))
{
$url = $reference_map[$link_definition];
strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&', $url);
if ($matches[1]) # image
{
$element = '';
}
else # anchor
{
$element_text = parse_span_elements($matches[2]);
$element = ''.$element_text.'';
}
$code = "\x1A".'$'.$index;
$text = str_replace($matches[0], $code, $text);
$map[$code] = $element;
$index ++;
}
}
}
# automatic link
if (strpos($text, '<') !== FALSE and preg_match_all('/<((https?|ftp|dict):[^\^\s]+?)>/i', $text, $matches, PREG_SET_ORDER))
{
foreach ($matches as $matches)
{
$url = $matches[1];
strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&', $url);
$element = ':text';
$element = str_replace(':text', $url, $element);
$element = str_replace(':href', $url, $element);
$code = "\x1A".'$'.$index;
$text = str_replace($matches[0], $code, $text);
$map[$code] = $element;
$index ++;
}
}
strpos($text, '&') !== FALSE and $text = preg_replace('/&(?!#?\w+;)/', '&', $text);
strpos($text, '<') !== FALSE and $text = preg_replace('/<(?!\/?\w.*?>)/', '<', $text);
if (strpos($text, '_') !== FALSE)
{
$text = preg_replace('/__(?=\S)(.+?)(?<=\S)__(?!_)/s', '$1', $text);
$text = preg_replace('/_(?=\S)(.+?)(?<=\S)_/s', '$1', $text);
}
if (strpos($text, '*') !== FALSE)
{
$text = preg_replace('/\*\*(?=\S)(.+?)(?<=\S)\*\*(?!\*)/s', '$1', $text);
$text = preg_replace('/\*(?=\S)(.+?)(?<=\S)\*/s', '$1', $text);
}
$text = strtr($text, $map);
return $text;
}
?>