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<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
* CodeIgniter
*
* An open source application development framework for PHP 5.1.6 or newer
*
* @package CodeIgniter
* @author ExpressionEngine Dev Team
* @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
* @license http://codeigniter.com/user_guide/license.html
* @link http://codeigniter.com
* @since Version 1.0
* @filesource
*/
// ------------------------------------------------------------------------
/**
* Typography Class
*
*
* @access private
* @category Helpers
* @author ExpressionEngine Dev Team
* @link http://codeigniter.com/user_guide/helpers/
*/
class CI_Typography {
// Block level elements that should not be wrapped inside <p> tags
var $block_elements = 'address|blockquote|div|dl|fieldset|form|h\d|hr|noscript|object|ol|p|pre|script|table|ul';
// Elements that should not have <p> and <br /> tags within them.
var $skip_elements = 'p|pre|ol|ul|dl|object|table|h\d';
// Tags we want the parser to completely ignore when splitting the string.
var $inline_elements = 'a|abbr|acronym|b|bdo|big|br|button|cite|code|del|dfn|em|i|img|ins|input|label|map|kbd|q|samp|select|small|span|strong|sub|sup|textarea|tt|var';
// array of block level elements that require inner content to be within another block level element
var $inner_block_required = array('blockquote');
// the last block element parsed
var $last_block_element = '';
// whether or not to protect quotes within { curly braces }
var $protect_braced_quotes = FALSE;
/**
* Auto Typography
*
* This function converts text, making it typographically correct:
* - Converts double spaces into paragraphs.
* - Converts single line breaks into <br /> tags
* - Converts single and double quotes into correctly facing curly quote entities.
* - Converts three dots into ellipsis.
* - Converts double dashes into em-dashes.
* - Converts two spaces into entities
*
* @access public
* @param string
* @param bool whether to reduce more then two consecutive newlines to two
* @return string
*/
function auto_typography($str, $reduce_linebreaks = FALSE)
{
if ($str == '')
{
return '';
}
// Standardize Newlines to make matching easier
if (strpos($str, "\r") !== FALSE)
{
$str = str_replace(array("\r\n", "\r"), "\n", $str);
}
// Reduce line breaks. If there are more than two consecutive linebreaks
// we'll compress them down to a maximum of two since there's no benefit to more.
if ($reduce_linebreaks === TRUE)
{
$str = preg_replace("/\n\n+/", "\n\n", $str);
}
// HTML comment tags don't conform to patterns of normal tags, so pull them out separately, only if needed
$html_comments = array();
if (strpos($str, '<!--') !== FALSE)
{
if (preg_match_all("#(<!\-\-.*?\-\->)#s", $str, $matches))
{
for ($i = 0, $total = count($matches[0]); $i < $total; $i++)
{
$html_comments[] = $matches[0][$i];
$str = str_replace($matches[0][$i], '{@HC'.$i.'}', $str);
}
}
}
// match and yank <pre> tags if they exist. It's cheaper to do this separately since most content will
// not contain <pre> tags, and it keeps the PCRE patterns below simpler and faster
if (strpos($str, '<pre') !== FALSE)
{
$str = preg_replace_callback("#<pre.*?>.*?</pre>#si", array($this, '_protect_characters'), $str);
}
// Convert quotes within tags to temporary markers.
$str = preg_replace_callback("#<.+?>#si", array($this, '_protect_characters'), $str);
// Do the same with braces if necessary
if ($this->protect_braced_quotes === TRUE)
{
$str = preg_replace_callback("#\{.+?\}#si", array($this, '_protect_characters'), $str);
}
// Convert "ignore" tags to temporary marker. The parser splits out the string at every tag
// it encounters. Certain inline tags, like image tags, links, span tags, etc. will be
// adversely affected if they are split out so we'll convert the opening bracket < temporarily to: {@TAG}
$str = preg_replace("#<(/*)(".$this->inline_elements.")([ >])#i", "{@TAG}\\1\\2\\3", $str);
// Split the string at every tag. This expression creates an array with this prototype:
//
// [array]
// {
// [0] = <opening tag>
// [1] = Content...
// [2] = <closing tag>
// Etc...
// }
$chunks = preg_split('/(<(?:[^<>]+(?:"[^"]*"|\'[^\']*\')?)+>)/', $str, -1, PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_NO_EMPTY);
// Build our finalized string. We cycle through the array, skipping tags, and processing the contained text
$str = '';
$process = TRUE;
$paragraph = FALSE;
$current_chunk = 0;
$total_chunks = count($chunks);
foreach ($chunks as $chunk)
{
$current_chunk++;
// Are we dealing with a tag? If so, we'll skip the processing for this cycle.
// Well also set the "process" flag which allows us to skip <pre> tags and a few other things.
if (preg_match("#<(/*)(".$this->block_elements.").*?>#", $chunk, $match))
{
if (preg_match("#".$this->skip_elements."#", $match[2]))
{
$process = ($match[1] == '/') ? TRUE : FALSE;
}
if ($match[1] == '')
{
$this->last_block_element = $match[2];
}
$str .= $chunk;
continue;
}
if ($process == FALSE)
{
$str .= $chunk;
continue;
}
// Force a newline to make sure end tags get processed by _format_newlines()
if ($current_chunk == $total_chunks)
{
$chunk .= "\n";
}
// Convert Newlines into <p> and <br /> tags
$str .= $this->_format_newlines($chunk);
}
// No opening block level tag? Add it if needed.
if ( ! preg_match("/^\s*<(?:".$this->block_elements.")/i", $str))
{
$str = preg_replace("/^(.*?)<(".$this->block_elements.")/i", '<p>$1</p><$2', $str);
}
// Convert quotes, elipsis, em-dashes, non-breaking spaces, and ampersands
$str = $this->format_characters($str);
// restore HTML comments
for ($i = 0, $total = count($html_comments); $i < $total; $i++)
{
// remove surrounding paragraph tags, but only if there's an opening paragraph tag
// otherwise HTML comments at the ends of paragraphs will have the closing tag removed
// if '<p>{@HC1}' then replace <p>{@HC1}</p> with the comment, else replace only {@HC1} with the comment
$str = preg_replace('#(?(?=<p>\{@HC'.$i.'\})<p>\{@HC'.$i.'\}(\s*</p>)|\{@HC'.$i.'\})#s', $html_comments[$i], $str);
}
// Final clean up
$table = array(
// If the user submitted their own paragraph tags within the text
// we will retain them instead of using our tags.
'/(<p[^>*?]>)<p>/' => '$1', // <?php BBEdit syntax coloring bug fix
// Reduce multiple instances of opening/closing paragraph tags to a single one
'#(</p>)+#' => '</p>',
'/(<p>\W*<p>)+/' => '<p>',
// Clean up stray paragraph tags that appear before block level elements
'#<p></p><('.$this->block_elements.')#' => '<$1',
// Clean up stray non-breaking spaces preceeding block elements
'#( \s*)+<('.$this->block_elements.')#' => ' <$2',
// Replace the temporary markers we added earlier
'/\{@TAG\}/' => '<',
'/\{@DQ\}/' => '"',
'/\{@SQ\}/' => "'",
'/\{@DD\}/' => '--',
'/\{@NBS\}/' => ' ',
// An unintended consequence of the _format_newlines function is that
// some of the newlines get truncated, resulting in <p> tags
// starting immediately after <block> tags on the same line.
// This forces a newline after such occurrences, which looks much nicer.
"/><p>\n/" => ">\n<p>",
// Similarly, there might be cases where a closing </block> will follow
// a closing </p> tag, so we'll correct it by adding a newline in between
"#</p></#" => "</p>\n</"
);
// Do we need to reduce empty lines?
if ($reduce_linebreaks === TRUE)
{
$table['#<p>\n*</p>#'] = '';
}
else
{
// If we have empty paragraph tags we add a non-breaking space
// otherwise most browsers won't treat them as true paragraphs
$table['#<p></p>#'] = '<p> </p>';
}
return preg_replace(array_keys($table), $table, $str);
}
// --------------------------------------------------------------------
/**
* Format Characters
*
* This function mainly converts double and single quotes
* to curly entities, but it also converts em-dashes,
* double spaces, and ampersands
*
* @access public
* @param string
* @return string
*/
function format_characters($str)
{
static $table;
if ( ! isset($table))
{
$table = array(
// nested smart quotes, opening and closing
// note that rules for grammar (English) allow only for two levels deep
// and that single quotes are _supposed_ to always be on the outside
// but we'll accommodate both
// Note that in all cases, whitespace is the primary determining factor
// on which direction to curl, with non-word characters like punctuation
// being a secondary factor only after whitespace is addressed.
'/\'"(\s|$)/' => '’”$1',
'/(^|\s|<p>)\'"/' => '$1‘“',
'/\'"(\W)/' => '’”$1',
'/(\W)\'"/' => '$1‘“',
'/"\'(\s|$)/' => '”’$1',
'/(^|\s|<p>)"\'/' => '$1“‘',
'/"\'(\W)/' => '”’$1',
'/(\W)"\'/' => '$1“‘',
// single quote smart quotes
'/\'(\s|$)/' => '’$1',
'/(^|\s|<p>)\'/' => '$1‘',
'/\'(\W)/' => '’$1',
'/(\W)\'/' => '$1‘',
// double quote smart quotes
'/"(\s|$)/' => '”$1',
'/(^|\s|<p>)"/' => '$1“',
'/"(\W)/' => '”$1',
'/(\W)"/' => '$1“',
// apostrophes
"/(\w)'(\w)/" => '$1’$2',
// Em dash and ellipses dots
'/\s?\-\-\s?/' => '—',
'/(\w)\.{3}/' => '$1…',
// double space after sentences
'/(\W) /' => '$1 ',
// ampersands, if not a character entity
'/&(?!#?[a-zA-Z0-9]{2,};)/' => '&'
);
}
return preg_replace(array_keys($table), $table, $str);
}
// --------------------------------------------------------------------
/**
* Format Newlines
*
* Converts newline characters into either <p> tags or <br />
*
* @access public
* @param string
* @return string
*/
function _format_newlines($str)
{
if ($str == '')
{
return $str;
}
if (strpos($str, "\n") === FALSE && ! in_array($this->last_block_element, $this->inner_block_required))
{
return $str;
}
// Convert two consecutive newlines to paragraphs
$str = str_replace("\n\n", "</p>\n\n<p>", $str);
// Convert single spaces to <br /> tags
$str = preg_replace("/([^\n])(\n)([^\n])/", "\\1<br />\\2\\3", $str);
// Wrap the whole enchilada in enclosing paragraphs
if ($str != "\n")
{
// We trim off the right-side new line so that the closing </p> tag
// will be positioned immediately following the string, matching
// the behavior of the opening <p> tag
$str = '<p>'.rtrim($str).'</p>';
}
// Remove empty paragraphs if they are on the first line, as this
// is a potential unintended consequence of the previous code
$str = preg_replace("/<p><\/p>(.*)/", "\\1", $str, 1);
return $str;
}
// ------------------------------------------------------------------------
/**
* Protect Characters
*
* Protects special characters from being formatted later
* We don't want quotes converted within tags so we'll temporarily convert them to {@DQ} and {@SQ}
* and we don't want double dashes converted to emdash entities, so they are marked with {@DD}
* likewise double spaces are converted to {@NBS} to prevent entity conversion
*
* @access public
* @param array
* @return string
*/
function _protect_characters($match)
{
return str_replace(array("'",'"','--',' '), array('{@SQ}', '{@DQ}', '{@DD}', '{@NBS}'), $match[0]);
}
// --------------------------------------------------------------------
/**
* Convert newlines to HTML line breaks except within PRE tags
*
* @access public
* @param string
* @return string
*/
function nl2br_except_pre($str)
{
$ex = explode("pre>",$str);
$ct = count($ex);
$newstr = "";
for ($i = 0; $i < $ct; $i++)
{
if (($i % 2) == 0)
{
$newstr .= nl2br($ex[$i]);
}
else
{
$newstr .= $ex[$i];
}
if ($ct - 1 != $i)
$newstr .= "pre>";
}
return $newstr;
}
}
// END Typography Class
/* End of file Typography.php */
/* Location: ./system/libraries/Typography.php */
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