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authorFlorian Pritz <bluewind@xssn.at>2010-02-06 23:14:56 +0100
committerFlorian Pritz <bluewind@xssn.at>2010-02-06 23:31:27 +0100
commit9e9d77b4072de4f8c73e8bbade07a8f27734e4bd (patch)
treea5d709254968fed8f3acdb9eec68fde2faa14b94 /system/libraries/Typography.php
Initial commit
Signed-off-by: Florian Pritz <bluewind@xssn.at>
Diffstat (limited to 'system/libraries/Typography.php')
-rw-r--r--system/libraries/Typography.php406
1 files changed, 406 insertions, 0 deletions
diff --git a/system/libraries/Typography.php b/system/libraries/Typography.php
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+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 4.3.2 or newer
+ *
+ * @package CodeIgniter
+ * @author ExpressionEngine Dev Team
+ * @copyright Copyright (c) 2008 - 2009, 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 $protect_braced_quotes = FALSE;
+
+ /**
+ * Nothing to do here...
+ *
+ */
+ function CI_Typography()
+ {
+ }
+
+ /**
+ * Auto Typography
+ *
+ * This function converts text, making it typographically correct:
+ * - Converts double spaces into paragraphs.
+ * - Converts single line breaks into <br /> tags
+ * - Converts single and double quotes into correctly facing curly quote entities.
+ * - Converts three dots into ellipsis.
+ * - Converts double dashes into em-dashes.
+ * - Converts two spaces into entities
+ *
+ * @access public
+ * @param string
+ * @param bool whether to reduce more then two consecutive newlines to two
+ * @return string
+ */
+ function auto_typography($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.')#' => '<$1',
+
+ // Clean up stray non-breaking spaces preceeding block elements
+ '#(&nbsp;\s*)+<('.$this->block_elements.')#' => ' <$2',
+
+ // Replace the temporary markers we added earlier
+ '/\{@TAG\}/' => '<',
+ '/\{@DQ\}/' => '"',
+ '/\{@SQ\}/' => "'",
+ '/\{@DD\}/' => '--',
+ '/\{@NBS\}/' => ' '
+
+ );
+
+ // Do we need to reduce empty lines?
+ if ($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
+ $table['#<p></p>#'] = '<p>&nbsp;</p>';
+ }
+
+ return preg_replace(array_keys($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))
+ {
+ $table = array(
+ // nested smart quotes, opening and closing
+ // note that rules for grammar (English) allow only for two levels deep
+ // and that single quotes are _supposed_ to always be on the outside
+ // but we'll accommodate both
+ // Note that in all cases, whitespace is the primary determining factor
+ // on which direction to curl, with non-word characters like punctuation
+ // being a secondary factor only after whitespace is addressed.
+ '/\'"(\s|$)/' => '&#8217;&#8221;$1',
+ '/(^|\s|<p>)\'"/' => '$1&#8216;&#8220;',
+ '/\'"(\W)/' => '&#8217;&#8221;$1',
+ '/(\W)\'"/' => '$1&#8216;&#8220;',
+ '/"\'(\s|$)/' => '&#8221;&#8217;$1',
+ '/(^|\s|<p>)"\'/' => '$1&#8220;&#8216;',
+ '/"\'(\W)/' => '&#8221;&#8217;$1',
+ '/(\W)"\'/' => '$1&#8220;&#8216;',
+
+ // single quote smart quotes
+ '/\'(\s|$)/' => '&#8217;$1',
+ '/(^|\s|<p>)\'/' => '$1&#8216;',
+ '/\'(\W)/' => '&#8217;$1',
+ '/(\W)\'/' => '$1&#8216;',
+
+ // double quote smart quotes
+ '/"(\s|$)/' => '&#8221;$1',
+ '/(^|\s|<p>)"/' => '$1&#8220;',
+ '/"(\W)/' => '&#8221;$1',
+ '/(\W)"/' => '$1&#8220;',
+
+ // apostrophes
+ "/(\w)'(\w)/" => '$1&#8217;$2',
+
+ // Em dash and ellipses dots
+ '/\s?\-\-\s?/' => '&#8212;',
+ '/(\w)\.{3}/' => '$1&#8230;',
+
+ // double space after sentences
+ '/(\W) /' => '$1&nbsp; ',
+
+ // ampersands, if not a character entity
+ '/&(?!#?[a-zA-Z0-9]{2,};)/' => '&amp;'
+ );
+ }
+
+ return preg_replace(array_keys($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")
+ {
+ $str = '<p>'.$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 */ \ No newline at end of file