', '\#', '\+', '\-', '\.', '\!'); 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 = preg_replace('/\n\s*\n/', "\n\n", $text); $text = trim($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_code_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'] .= $line; } continue 2; } break; case 'markup': if ( ! isset($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 2; } break; } # * if ($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; continue 2; } } else { $line = preg_replace('/^[ ]{0,4}/', '', $line); $element['lines'] []= $line; continue 2; } break; } # # indentation sensitive types $deindented_line = $line; switch ($line[0]) { case ' ': # ~ $deindented_line = ltrim($line); if ($deindented_line === '') { continue 2; } # code block if (preg_match('/^[ ]{4}(.*)/', $line, $matches)) { if ($element['type'] === 'code_block') { if (isset($element['interrupted'])) { $element['text'] .= "\n"; unset ($element['interrupted']); } $element['text'] .= "\n".$matches[1]; } else { $elements []= $element; $element = array( 'type' => 'code_block', 'text' => $matches[1], ); } continue 2; } break; case '#': # atx heading (#) if (preg_match('/^(#{1,6})[ ]*(.+?)[ ]*#*$/', $line, $matches)) { $elements []= $element; $level = strlen($matches[1]); $element = array( 'type' => 'h.', 'text' => $matches[2], 'level' => $level, ); continue 2; } break; case '-': # setext heading (---) if ($line[0] === '-' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[-]+[ ]*$/', $line)) { $element['type'] = 'h.'; $element['level'] = 2; continue 2; } break; case '=': # setext heading (===) if ($line[0] === '=' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[=]+[ ]*$/', $line)) { $element['type'] = 'h.'; $element['level'] = 1; continue 2; } break; } # # indentation insensitive types switch ($deindented_line[0]) { case '<': # self-closing tag if (preg_match('{^<.+?/>$}', $deindented_line)) { $elements []= $element; $element = array( 'type' => '', 'text' => $deindented_line, ); continue 2; } # 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 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] = trim($matches[2], '<>');; continue 2; } break; case '`': case '~': # fenced code block if (preg_match('/^([`]{3,}|[~]{3,})[ ]*(\S+)?[ ]*$/', $deindented_line, $matches)) { $elements []= $element; $element = array( 'type' => 'fenced_code_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' 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'] === '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 []= $element; unset($elements[0]); # # ~ # $markup = ''; foreach ($elements as $element) { switch ($element['type']) { case 'p': $text = $this->parse_span_elements($element['text']); $text = preg_replace('/[ ]{2}\n/', '
'."\n", $text); if ($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_code_block': $text = htmlspecialchars($element['text'], ENT_NOQUOTES); strpos($text, "\x1A\\") !== FALSE and $text = strtr($text, $this->escape_sequence_map); $markup .= '
'.$text.'
'."\n"; break; case 'h.': $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; default: $markup .= $element['text']."\n"; } } return $markup; } private function parse_span_elements($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]; $element_text = htmlspecialchars($element_text, ENT_NOQUOTES); # decodes escape sequences $this->escape_sequence_map and strpos($element_text, "\x1A") !== FALSE and $element_text = strtr($element_text, $this->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].''; } else { $element_text = $this->parse_span_elements($matches[3]); $element = ''.$element_text.''; } # ~ $code = "\x1A".'$'.$index; $text = str_replace($matches[0], $code, $text); $map[$code] = $element; $index ++; } } # reference link or image if ($this->reference_map and 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($this->reference_map[$link_definition])) { $url = $this->reference_map[$link_definition]; strpos($url, '&') !== FALSE and $url = preg_replace('/&(?!#?\w+;)/', '&', $url); if ($matches[1]) # image { $element = ''.$matches[2].''; } else # anchor { $element_text = $this->parse_span_elements($matches[2]); $element = ''.$element_text.''; } # ~ $code = "\x1A".'$'.$index; $text = str_replace($matches[0], $code, $text); $map[$code] = $element; $index ++; } } } if (strpos($text, '://') !== FALSE) { switch (TRUE) { case preg_match_all('{<(https?:[/]{2}[^\s]+)>}i', $text, $matches, PREG_SET_ORDER): case preg_match_all('{\b(https?:[/]{2}[^\s]+)\b}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; $index ++; } break; } } # ~ strpos($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', $text); } if (strpos($text, '_') !== FALSE) { $text = preg_replace('/__(?=\S)(.+?)(?<=\S)__(?!_)/s', '$1', $text); $text = preg_replace('/\b_(?=\S)(.+?)(?<=\S)_\b/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; } }