break_marker = $breaks_enabled ? "\n" : " \n";
return $this;
}
#
# Fields
#
private $reference_map = array();
private $escape_sequence_map = array();
#
# Public Methods
#
function parse($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);
$this->escape_sequence_map[$code] = $escape_sequence;
}
}
}
# ~
$text = trim($text, "\n");
$lines = explode("\n", $text);
$text = $this->parse_block_elements($lines);
# decodes escape sequences
foreach ($this->escape_sequence_map as $code => $escape_sequence)
{
$text = str_replace($code, $escape_sequence[1], $text);
}
# ~
$text = rtrim($text, "\n");
return $text;
}
#
# Private Methods
#
private function parse_block_elements(array $lines, $context = '')
{
$elements = array();
$element = array(
'type' => '',
);
foreach ($lines as $line)
{
# fenced elements
switch ($element['type'])
{
case 'fenced block':
if ( ! isset($element['closed']))
{
if (preg_match('/^[ ]*'.$element['fence'][0].'{3,}[ ]*$/', $line))
{
$element['closed'] = true;
}
else
{
$element['text'] !== '' and $element['text'] .= "\n";
$element['text'] .= $line;
}
continue 2;
}
break;
case 'block-level markup':
if ( ! isset($element['closed']))
{
if (preg_match('{<'.$element['root '].'>$}', $line)) # opening tag
{
$element['depth']++;
}
if (preg_match('{$}', $line)) # closing tag
{
$element['depth'] > 0
? $element['depth']--
: $element['closed'] = true;
}
$element['text'] .= "\n".$line;
continue 2;
}
break;
}
# *
$deindented_line = ltrim($line);
if ($deindented_line === '')
{
$element['interrupted'] = true;
continue;
}
# composite elements
switch ($element['type'])
{
case 'blockquote':
if ( ! isset($element['interrupted']))
{
$line = preg_replace('/^[ ]*>[ ]?/', '', $line);
$element['lines'] []= $line;
continue 2;
}
break;
case '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}/', '', $matches[3]),
),
);
}
continue 2;
}
if (isset($element['interrupted']))
{
if ($line[0] === ' ')
{
$element['lines'] []= '';
$line = preg_replace('/^[ ]{0,4}/', '', $line);
$element['lines'] []= $line;
unset($element['interrupted']);
continue 2;
}
}
else
{
$line = preg_replace('/^[ ]{0,4}/', '', $line);
$element['lines'] []= $line;
continue 2;
}
break;
}
# indentation sensitive types
switch ($line[0])
{
case ' ':
# code block
if (isset($line[3]) and $line[3] === ' ' and $line[2] === ' ' and $line[1] === ' ')
{
$code_line = substr($line, 4);
if ($element['type'] === 'code block')
{
if (isset($element['interrupted']))
{
$element['text'] .= "\n";
unset ($element['interrupted']);
}
$element['text'] .= "\n".$code_line;
}
else
{
$elements []= $element;
$element = array(
'type' => 'code block',
'text' => $code_line,
);
}
continue 2;
}
break;
case '#':
# atx heading (#)
if (preg_match('/^(#{1,6})[ ]*(.+?)[ ]*#*$/', $line, $matches))
{
$elements []= $element;
$level = strlen($matches[1]);
$element = array(
'type' => 'heading',
'text' => $matches[2],
'level' => $level,
);
continue 2;
}
break;
case '-':
# setext heading (---)
if ($line[0] === '-' and $element['type'] === 'paragraph' and ! isset($element['interrupted']) and preg_match('/^[-]+[ ]*$/', $line))
{
$element['type'] = 'heading';
$element['level'] = 2;
continue 2;
}
break;
case '=':
# setext heading (===)
if ($line[0] === '=' and $element['type'] === 'paragraph' and ! isset($element['interrupted']) and preg_match('/^[=]+[ ]*$/', $line))
{
$element['type'] = 'heading';
$element['level'] = 1;
continue 2;
}
break;
}
# indentation insensitive types
switch ($deindented_line[0])
{
case '<':
# self-closing tag
if (preg_match('{^<.+?/>$}', $deindented_line))
{
$elements []= $element;
$element = array(
'type' => 'self-closing tag',
'text' => $deindented_line,
);
continue 2;
}
# opening tag
if (preg_match('{^<(\w+)(?:[ ].*?)?>}', $deindented_line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'block-level markup',
'text' => $deindented_line,
'root ' => strtolower($matches[1]),
'depth' => 0,
);
preg_match('{\s*$}', $deindented_line) and $element['closed'] = true;
continue 2;
}
break;
case '>':
# quote
if (preg_match('/^>[ ]?(.*)/', $deindented_line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'blockquote',
'lines' => array(
$matches[1],
),
);
continue 2;
}
break;
case '[':
# reference
if (preg_match('/^\[(.+?)\]:[ ]*(.+?)(?:[ ]+[\'"](.+?)[\'"])?[ ]*$/', $deindented_line, $matches))
{
$label = strtolower($matches[1]);
$this->reference_map[$label] = array(
'»' => trim($matches[2], '<>'),
);
if (isset($matches[3]))
{
$this->reference_map[$label]['#'] = $matches[3];
}
continue 2;
}
break;
case '`':
case '~':
# fenced code block
if (preg_match('/^([`]{3,}|[~]{3,})[ ]*(\S+)?[ ]*$/', $deindented_line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'fenced block',
'text' => '',
'fence' => $matches[1],
);
isset($matches[2]) and $element['language'] = $matches[2];
continue 2;
}
break;
case '*':
case '+':
case '-':
case '_':
# hr
if (preg_match('/^([-*_])([ ]{0,2}\1){2,}[ ]*$/', $deindented_line))
{
$elements []= $element;
$element = array(
'type' => 'hr',
);
continue 2;
}
# li
if (preg_match('/^([ ]*)[*+-][ ](.*)/', $line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'li',
'ordered' => false,
'indentation' => $matches[1],
'last' => true,
'lines' => array(
preg_replace('/^[ ]{0,4}/', '', $matches[2]),
),
);
continue 2;
}
}
# li
if ($deindented_line[0] <= '9' and $deindented_line[0] >= '0' and preg_match('/^([ ]*)\d+[.][ ](.*)/', $line, $matches))
{
$elements []= $element;
$element = array(
'type' => 'li',
'ordered' => true,
'indentation' => $matches[1],
'last' => true,
'lines' => array(
preg_replace('/^[ ]{0,4}/', '', $matches[2]),
),
);
continue;
}
# paragraph
if ($element['type'] === 'paragraph')
{
if (isset($element['interrupted']))
{
$elements []= $element;
$element['text'] = $line;
unset($element['interrupted']);
}
else
{
$element['text'] .= "\n".$line;
}
}
else
{
$elements []= $element;
$element = array(
'type' => 'paragraph',
'text' => $line,
);
}
}
$elements []= $element;
unset($elements[0]);
#
# ~
#
$markup = '';
foreach ($elements as $element)
{
switch ($element['type'])
{
case 'paragraph':
$text = $this->parse_span_elements($element['text']);
if ($context === 'li' and $markup === '')
{
if (isset($element['interrupted']))
{
$markup .= "\n".''.$text.'
'."\n";
}
else
{
$markup .= $text;
}
}
else
{
$markup .= ''.$text.'
'."\n";
}
break;
case 'blockquote':
$text = $this->parse_block_elements($element['lines']);
$markup .= ''."\n".$text.'
'."\n";
break;
case 'code block':
case 'fenced block':
$text = htmlspecialchars($element['text'], ENT_NOQUOTES, 'UTF-8');
strpos($text, "\x1A\\") !== FALSE and $text = strtr($text, $this->escape_sequence_map);
$markup .= isset($element['language'])
? ''.$text.'
'
: ''.$text.'
';
$markup .= "\n";
break;
case 'heading':
$text = $this->parse_span_elements($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 = $this->parse_block_elements($element['lines'], 'li');
$markup .= ''.$text.''."\n";
isset($element['last']) and $markup .= ''."\n";
break;
case 'block-level markup':
$markup .= $this->parse_span_elements($element['text'])."\n";
break;
default:
$markup .= $element['text']."\n";
}
}
return $markup;
}
# ~
private $strong_regex = array(
'*' => '/^[*]{2}([^*]+?)[*]{2}(?![*])/s',
'_' => '/^__([^_]+?)__(?!_)/s',
);
private $em_regex = array(
'*' => '/^[*]([^*]+?)[*](?![*])/s',
'_' => '/^_([^_]+?)[_](?![_])\b/s',
);
private $strong_em_regex = array(
'*' => '/^[*]{2}(.*?)[*](.+?)[*](.*?)[*]{2}/s',
'_' => '/^__(.*?)_(.+?)_(.*?)__/s',
);
private $em_strong_regex = array(
'*' => '/^[*](.*?)[*]{2}(.+?)[*]{2}(.*?)[*]/s',
'_' => '/^_(.*?)__(.+?)__(.*?)_/s',
);
private function parse_span_elements($text, $markers = array('![', '&', '*', '<', '[', '_', '`', 'http', '~~'))
{
if (isset($text[2]) === false or $markers === array())
{
return $text;
}
# ~
$markup = '';
while ($markers)
{
$closest_marker = null;
$closest_marker_index = 0;
$closest_marker_position = null;
foreach ($markers as $index => $marker)
{
$marker_position = strpos($text, $marker);
if ($marker_position === false)
{
unset($markers[$index]);
continue;
}
if ($closest_marker === null or $marker_position < $closest_marker_position)
{
$closest_marker = $marker;
$closest_marker_index = $index;
$closest_marker_position = $marker_position;
}
}
# ~
if ($closest_marker === null or isset($text[$closest_marker_position + 2]) === false)
{
$markup .= $text;
break;
}
else
{
$markup .= substr($text, 0, $closest_marker_position);
}
$text = substr($text, $closest_marker_position);
# ~
unset($markers[$closest_marker_index]);
# ~
switch ($closest_marker)
{
case '![':
case '[':
if (strpos($text, ']') and preg_match('/\[((?:[^][]|(?R))*)\]/', $text, $matches))
{
$element = array(
'!' => $text[0] === '!',
'a' => $matches[1],
);
$offset = strlen($matches[0]);
$element['!'] and $offset++;
$remaining_text = substr($text, $offset);
if ($remaining_text[0] === '(' and preg_match('/\([ ]*(.*?)(?:[ ]+[\'"](.+?)[\'"])?[ ]*\)/', $remaining_text, $matches))
{
$element['»'] = $matches[1];
if (isset($matches[2]))
{
$element['#'] = $matches[2];
}
$offset += strlen($matches[0]);
}
elseif ($this->reference_map)
{
$reference = $element['a'];
if (preg_match('/^\s*\[(.*?)\]/', $remaining_text, $matches))
{
$reference = $matches[1] ? $matches[1] : $element['a'];
$offset += strlen($matches[0]);
}
$reference = strtolower($reference);
if (isset($this->reference_map[$reference]))
{
$element['»'] = $this->reference_map[$reference]['»'];
if (isset($this->reference_map[$reference]['#']))
{
$element['#'] = $this->reference_map[$reference]['#'];
}
}
else
{
unset($element);
}
}
else
{
unset($element);
}
}
if (isset($element))
{
$element['»'] = str_replace('&', '&', $element['»']);
$element['»'] = str_replace('<', '<', $element['»']);
if ($element['!'])
{
$markup .= '!['.$element['a'].']('.$element['»'].')
';
}
else
{
$element['a'] = $this->parse_span_elements($element['a'], $markers);
$markup .= isset($element['#'])
? ''.$element['a'].''
: ''.$element['a'].'';
}
unset($element);
}
else
{
$markup .= $closest_marker;
$offset = $closest_marker === '![' ? 2 : 1;
}
break;
case '&':
$markup .= '&';
$offset = substr($text, 0, 5) === '&' ? 5 : 1;
break;
case '*':
case '_':
if ($text[1] === $closest_marker and preg_match($this->strong_regex[$closest_marker], $text, $matches))
{
$matches[1] = $this->parse_span_elements($matches[1], $markers);
$markup .= ''.$matches[1].'';
}
elseif (preg_match($this->em_regex[$closest_marker], $text, $matches))
{
$matches[1] = $this->parse_span_elements($matches[1], $markers);
$markup .= ''.$matches[1].'';
}
elseif ($text[1] === $closest_marker and preg_match($this->strong_em_regex[$closest_marker], $text, $matches))
{
$matches[2] = $this->parse_span_elements($matches[2], $markers);
$matches[1] and $matches[1] = $this->parse_span_elements($matches[1], $markers);
$matches[3] and $matches[3] = $this->parse_span_elements($matches[3], $markers);
$markup .= ''.$matches[1].''.$matches[2].''.$matches[3].'';
}
elseif (preg_match($this->em_strong_regex[$closest_marker], $text, $matches))
{
$matches[2] = $this->parse_span_elements($matches[2], $markers);
$matches[1] and $matches[1] = $this->parse_span_elements($matches[1], $markers);
$matches[3] and $matches[3] = $this->parse_span_elements($matches[3], $markers);
$markup .= ''.$matches[1].''.$matches[2].''.$matches[3].'';
}
if (isset($matches) and $matches)
{
$offset = strlen($matches[0]);
}
else
{
$markup .= $closest_marker;
$offset = 1;
}
break;
case '<':
if (strpos($text, '>') !== false)
{
if ($text[1] === 'h' and preg_match('/^<(https?:[\/]{2}[^\s]+?)>/i', $text, $matches))
{
$element_url = $matches[1];
$element_url = str_replace('&', '&', $element_url);
$element_url = str_replace('<', '<', $element_url);
$markup .= ''.$element_url.'';
$offset = strlen($matches[0]);
}
elseif (preg_match('/^<\/?\w.*?>/', $text, $matches))
{
$markup .= $matches[0];
$offset = strlen($matches[0]);
}
else
{
$markup .= '<';
$offset = 1;
}
}
else
{
$markup .= '<';
$offset = 1;
}
break;
case '`':
if (preg_match('/^`(.+?)`/', $text, $matches))
{
$element_text = $matches[1];
$element_text = htmlspecialchars($element_text, ENT_NOQUOTES, 'UTF-8');
if ($this->escape_sequence_map and strpos($element_text, "\x1A") !== false)
{
$element_text = strtr($element_text, $this->escape_sequence_map);
}
$markup .= ''.$element_text.'';
$offset = strlen($matches[0]);
}
else
{
$markup .= '`';
$offset = 1;
}
break;
case 'http':
if (preg_match('/^https?:[\/]{2}[^\s]+\b/i', $text, $matches))
{
$element_url = $matches[0];
$element_url = str_replace('&', '&', $element_url);
$element_url = str_replace('<', '<', $element_url);
$markup .= ''.$element_url.'';
$offset = strlen($matches[0]);
}
else
{
$markup .= 'http';
$offset = 4;
}
break;
case '~~':
if (preg_match('/^~~(?=\S)(.+?)(?<=\S)~~/', $text, $matches))
{
$matches[1] = $this->parse_span_elements($matches[1], $markers);
$markup .= ''.$matches[1].'';
$offset = strlen($matches[0]);
}
else
{
$markup .= '~~';
$offset = 2;
}
break;
}
if (isset($offset))
{
$text = substr($text, $offset);
}
$markers[$closest_marker_index] = $closest_marker;
}
$markup = str_replace($this->break_marker, '
'."\n", $markup);
return $markup;
}
}