summaryrefslogtreecommitdiff
path: root/program/lib/Roundcube/rcube_html2text.php
diff options
context:
space:
mode:
authorThomas Bruederli <thomas@roundcube.net>2012-12-26 18:49:06 +0100
committerThomas Bruederli <thomas@roundcube.net>2012-12-26 18:49:06 +0100
commitc942e4a2e9a97743850b4178ea66b3b33956e7f7 (patch)
tree8fda2746e6cd6e69fc74427c297f3113665fce00 /program/lib/Roundcube/rcube_html2text.php
parentaabeab1e4e08ffba5d709aa71de1182dfeb698d1 (diff)
parent23b30e0afca5f9c31e05204c3a6ff3332791d3a1 (diff)
Merge branch 'master' of github.com:roundcube/roundcubemail
Diffstat (limited to 'program/lib/Roundcube/rcube_html2text.php')
-rw-r--r--program/lib/Roundcube/rcube_html2text.php691
1 files changed, 691 insertions, 0 deletions
diff --git a/program/lib/Roundcube/rcube_html2text.php b/program/lib/Roundcube/rcube_html2text.php
new file mode 100644
index 000000000..0b172ebfa
--- /dev/null
+++ b/program/lib/Roundcube/rcube_html2text.php
@@ -0,0 +1,691 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | This file is part of the Roundcube Webmail client |
+ | Copyright (C) 2008-2012, The Roundcube Dev Team |
+ | Copyright (c) 2005-2007, Jon Abernathy <jon@chuggnutt.com> |
+ | |
+ | Licensed under the GNU General Public License version 3 or |
+ | any later version with exceptions for skins & plugins. |
+ | See the README file for a full license statement. |
+ | |
+ | PURPOSE: |
+ | Converts HTML to formatted plain text (based on html2text class) |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com> |
+ | Author: Aleksander Machniak <alec@alec.pl> |
+ | Author: Jon Abernathy <jon@chuggnutt.com> |
+ +-----------------------------------------------------------------------+
+ */
+
+/**
+ * Takes HTML and converts it to formatted, plain text.
+ *
+ * Thanks to Alexander Krug (http://www.krugar.de/) to pointing out and
+ * correcting an error in the regexp search array. Fixed 7/30/03.
+ *
+ * Updated set_html() function's file reading mechanism, 9/25/03.
+ *
+ * Thanks to Joss Sanglier (http://www.dancingbear.co.uk/) for adding
+ * several more HTML entity codes to the $search and $replace arrays.
+ * Updated 11/7/03.
+ *
+ * Thanks to Darius Kasperavicius (http://www.dar.dar.lt/) for
+ * suggesting the addition of $allowed_tags and its supporting function
+ * (which I slightly modified). Updated 3/12/04.
+ *
+ * Thanks to Justin Dearing for pointing out that a replacement for the
+ * <TH> tag was missing, and suggesting an appropriate fix.
+ * Updated 8/25/04.
+ *
+ * Thanks to Mathieu Collas (http://www.myefarm.com/) for finding a
+ * display/formatting bug in the _build_link_list() function: email
+ * readers would show the left bracket and number ("[1") as part of the
+ * rendered email address.
+ * Updated 12/16/04.
+ *
+ * Thanks to Wojciech Bajon (http://histeria.pl/) for submitting code
+ * to handle relative links, which I hadn't considered. I modified his
+ * code a bit to handle normal HTTP links and MAILTO links. Also for
+ * suggesting three additional HTML entity codes to search for.
+ * Updated 03/02/05.
+ *
+ * Thanks to Jacob Chandler for pointing out another link condition
+ * for the _build_link_list() function: "https".
+ * Updated 04/06/05.
+ *
+ * Thanks to Marc Bertrand (http://www.dresdensky.com/) for
+ * suggesting a revision to the word wrapping functionality; if you
+ * specify a $width of 0 or less, word wrapping will be ignored.
+ * Updated 11/02/06.
+ *
+ * *** Big housecleaning updates below:
+ *
+ * Thanks to Colin Brown (http://www.sparkdriver.co.uk/) for
+ * suggesting the fix to handle </li> and blank lines (whitespace).
+ * Christian Basedau (http://www.movetheweb.de/) also suggested the
+ * blank lines fix.
+ *
+ * Special thanks to Marcus Bointon (http://www.synchromedia.co.uk/),
+ * Christian Basedau, Norbert Laposa (http://ln5.co.uk/),
+ * Bas van de Weijer, and Marijn van Butselaar
+ * for pointing out my glaring error in the <th> handling. Marcus also
+ * supplied a host of fixes.
+ *
+ * Thanks to Jeffrey Silverman (http://www.newtnotes.com/) for pointing
+ * out that extra spaces should be compressed--a problem addressed with
+ * Marcus Bointon's fixes but that I had not yet incorporated.
+ *
+ * Thanks to Daniel Schledermann (http://www.typoconsult.dk/) for
+ * suggesting a valuable fix with <a> tag handling.
+ *
+ * Thanks to Wojciech Bajon (again!) for suggesting fixes and additions,
+ * including the <a> tag handling that Daniel Schledermann pointed
+ * out but that I had not yet incorporated. I haven't (yet)
+ * incorporated all of Wojciech's changes, though I may at some
+ * future time.
+ *
+ * *** End of the housecleaning updates. Updated 08/08/07.
+ */
+
+/**
+ * Converts HTML to formatted plain text
+ *
+ * @package Framework
+ * @subpackage Utils
+ */
+class rcube_html2text
+{
+ /**
+ * Contains the HTML content to convert.
+ *
+ * @var string $html
+ */
+ protected $html;
+
+ /**
+ * Contains the converted, formatted text.
+ *
+ * @var string $text
+ */
+ protected $text;
+
+ /**
+ * Maximum width of the formatted text, in columns.
+ *
+ * Set this value to 0 (or less) to ignore word wrapping
+ * and not constrain text to a fixed-width column.
+ *
+ * @var integer $width
+ */
+ protected $width = 70;
+
+ /**
+ * Target character encoding for output text
+ *
+ * @var string $charset
+ */
+ protected $charset = 'UTF-8';
+
+ /**
+ * List of preg* regular expression patterns to search for,
+ * used in conjunction with $replace.
+ *
+ * @var array $search
+ * @see $replace
+ */
+ protected $search = array(
+ "/\r/", // Non-legal carriage return
+ "/[\n\t]+/", // Newlines and tabs
+ '/<head[^>]*>.*?<\/head>/i', // <head>
+ '/<script[^>]*>.*?<\/script>/i', // <script>s -- which strip_tags supposedly has problems with
+ '/<style[^>]*>.*?<\/style>/i', // <style>s -- which strip_tags supposedly has problems with
+ '/<p[^>]*>/i', // <P>
+ '/<br[^>]*>/i', // <br>
+ '/<i[^>]*>(.*?)<\/i>/i', // <i>
+ '/<em[^>]*>(.*?)<\/em>/i', // <em>
+ '/(<ul[^>]*>|<\/ul>)/i', // <ul> and </ul>
+ '/(<ol[^>]*>|<\/ol>)/i', // <ol> and </ol>
+ '/<li[^>]*>(.*?)<\/li>/i', // <li> and </li>
+ '/<li[^>]*>/i', // <li>
+ '/<hr[^>]*>/i', // <hr>
+ '/<div[^>]*>/i', // <div>
+ '/(<table[^>]*>|<\/table>)/i', // <table> and </table>
+ '/(<tr[^>]*>|<\/tr>)/i', // <tr> and </tr>
+ '/<td[^>]*>(.*?)<\/td>/i', // <td> and </td>
+ );
+
+ /**
+ * List of pattern replacements corresponding to patterns searched.
+ *
+ * @var array $replace
+ * @see $search
+ */
+ protected $replace = array(
+ '', // Non-legal carriage return
+ ' ', // Newlines and tabs
+ '', // <head>
+ '', // <script>s -- which strip_tags supposedly has problems with
+ '', // <style>s -- which strip_tags supposedly has problems with
+ "\n\n", // <P>
+ "\n", // <br>
+ '_\\1_', // <i>
+ '_\\1_', // <em>
+ "\n\n", // <ul> and </ul>
+ "\n\n", // <ol> and </ol>
+ "\t* \\1\n", // <li> and </li>
+ "\n\t* ", // <li>
+ "\n-------------------------\n", // <hr>
+ "<div>\n", // <div>
+ "\n\n", // <table> and </table>
+ "\n", // <tr> and </tr>
+ "\t\t\\1\n", // <td> and </td>
+ );
+
+ /**
+ * List of preg* regular expression patterns to search for,
+ * used in conjunction with $ent_replace.
+ *
+ * @var array $ent_search
+ * @see $ent_replace
+ */
+ protected $ent_search = array(
+ '/&(nbsp|#160);/i', // Non-breaking space
+ '/&(quot|rdquo|ldquo|#8220|#8221|#147|#148);/i',
+ // Double quotes
+ '/&(apos|rsquo|lsquo|#8216|#8217);/i', // Single quotes
+ '/&gt;/i', // Greater-than
+ '/&lt;/i', // Less-than
+ '/&(copy|#169);/i', // Copyright
+ '/&(trade|#8482|#153);/i', // Trademark
+ '/&(reg|#174);/i', // Registered
+ '/&(mdash|#151|#8212);/i', // mdash
+ '/&(ndash|minus|#8211|#8722);/i', // ndash
+ '/&(bull|#149|#8226);/i', // Bullet
+ '/&(pound|#163);/i', // Pound sign
+ '/&(euro|#8364);/i', // Euro sign
+ '/&(amp|#38);/i', // Ampersand: see _converter()
+ '/[ ]{2,}/', // Runs of spaces, post-handling
+ );
+
+ /**
+ * List of pattern replacements corresponding to patterns searched.
+ *
+ * @var array $ent_replace
+ * @see $ent_search
+ */
+ protected $ent_replace = array(
+ ' ', // Non-breaking space
+ '"', // Double quotes
+ "'", // Single quotes
+ '>',
+ '<',
+ '(c)',
+ '(tm)',
+ '(R)',
+ '--',
+ '-',
+ '*',
+ '£',
+ 'EUR', // Euro sign. € ?
+ '|+|amp|+|', // Ampersand: see _converter()
+ ' ', // Runs of spaces, post-handling
+ );
+
+ /**
+ * List of preg* regular expression patterns to search for
+ * and replace using callback function.
+ *
+ * @var array $callback_search
+ */
+ protected $callback_search = array(
+ '/<(a) [^>]*href=("|\')([^"\']+)\2[^>]*>(.*?)<\/a>/i', // <a href="">
+ '/<(h)[123456]( [^>]*)?>(.*?)<\/h[123456]>/i', // h1 - h6
+ '/<(b)( [^>]*)?>(.*?)<\/b>/i', // <b>
+ '/<(strong)( [^>]*)?>(.*?)<\/strong>/i', // <strong>
+ '/<(th)( [^>]*)?>(.*?)<\/th>/i', // <th> and </th>
+ );
+
+ /**
+ * List of preg* regular expression patterns to search for in PRE body,
+ * used in conjunction with $pre_replace.
+ *
+ * @var array $pre_search
+ * @see $pre_replace
+ */
+ protected $pre_search = array(
+ "/\n/",
+ "/\t/",
+ '/ /',
+ '/<pre[^>]*>/',
+ '/<\/pre>/'
+ );
+
+ /**
+ * List of pattern replacements corresponding to patterns searched for PRE body.
+ *
+ * @var array $pre_replace
+ * @see $pre_search
+ */
+ protected $pre_replace = array(
+ '<br>',
+ '&nbsp;&nbsp;&nbsp;&nbsp;',
+ '&nbsp;',
+ '',
+ ''
+ );
+
+ /**
+ * Contains a list of HTML tags to allow in the resulting text.
+ *
+ * @var string $allowed_tags
+ * @see set_allowed_tags()
+ */
+ protected $allowed_tags = '';
+
+ /**
+ * Contains the base URL that relative links should resolve to.
+ *
+ * @var string $url
+ */
+ protected $url;
+
+ /**
+ * Indicates whether content in the $html variable has been converted yet.
+ *
+ * @var boolean $_converted
+ * @see $html, $text
+ */
+ protected $_converted = false;
+
+ /**
+ * Contains URL addresses from links to be rendered in plain text.
+ *
+ * @var array $_link_list
+ * @see _build_link_list()
+ */
+ protected $_link_list = array();
+
+ /**
+ * Boolean flag, true if a table of link URLs should be listed after the text.
+ *
+ * @var boolean $_do_links
+ * @see __construct()
+ */
+ protected $_do_links = true;
+
+ /**
+ * Constructor.
+ *
+ * If the HTML source string (or file) is supplied, the class
+ * will instantiate with that source propagated, all that has
+ * to be done it to call get_text().
+ *
+ * @param string $source HTML content
+ * @param boolean $from_file Indicates $source is a file to pull content from
+ * @param boolean $do_links Indicate whether a table of link URLs is desired
+ * @param integer $width Maximum width of the formatted text, 0 for no limit
+ */
+ function __construct($source = '', $from_file = false, $do_links = true, $width = 75, $charset = 'UTF-8')
+ {
+ if (!empty($source)) {
+ $this->set_html($source, $from_file);
+ }
+
+ $this->set_base_url();
+
+ $this->_do_links = $do_links;
+ $this->width = $width;
+ $this->charset = $charset;
+ }
+
+ /**
+ * Loads source HTML into memory, either from $source string or a file.
+ *
+ * @param string $source HTML content
+ * @param boolean $from_file Indicates $source is a file to pull content from
+ */
+ function set_html($source, $from_file = false)
+ {
+ if ($from_file && file_exists($source)) {
+ $this->html = file_get_contents($source);
+ }
+ else {
+ $this->html = $source;
+ }
+
+ $this->_converted = false;
+ }
+
+ /**
+ * Returns the text, converted from HTML.
+ *
+ * @return string Plain text
+ */
+ function get_text()
+ {
+ if (!$this->_converted) {
+ $this->_convert();
+ }
+
+ return $this->text;
+ }
+
+ /**
+ * Prints the text, converted from HTML.
+ */
+ function print_text()
+ {
+ print $this->get_text();
+ }
+
+ /**
+ * Sets the allowed HTML tags to pass through to the resulting text.
+ *
+ * Tags should be in the form "<p>", with no corresponding closing tag.
+ */
+ function set_allowed_tags($allowed_tags = '')
+ {
+ if (!empty($allowed_tags)) {
+ $this->allowed_tags = $allowed_tags;
+ }
+ }
+
+ /**
+ * Sets a base URL to handle relative links.
+ */
+ function set_base_url($url = '')
+ {
+ if (empty($url)) {
+ if (!empty($_SERVER['HTTP_HOST'])) {
+ $this->url = 'http://' . $_SERVER['HTTP_HOST'];
+ }
+ else {
+ $this->url = '';
+ }
+ }
+ else {
+ // Strip any trailing slashes for consistency (relative
+ // URLs may already start with a slash like "/file.html")
+ if (substr($url, -1) == '/') {
+ $url = substr($url, 0, -1);
+ }
+ $this->url = $url;
+ }
+ }
+
+ /**
+ * Workhorse function that does actual conversion (calls _converter() method).
+ */
+ protected function _convert()
+ {
+ // Variables used for building the link list
+ $this->_link_list = array();
+
+ $text = trim(stripslashes($this->html));
+
+ // Convert HTML to TXT
+ $this->_converter($text);
+
+ // Add link list
+ if (!empty($this->_link_list)) {
+ $text .= "\n\nLinks:\n------\n";
+ foreach ($this->_link_list as $idx => $url) {
+ $text .= '[' . ($idx+1) . '] ' . $url . "\n";
+ }
+ }
+
+ $this->text = $text;
+ $this->_converted = true;
+ }
+
+ /**
+ * Workhorse function that does actual conversion.
+ *
+ * First performs custom tag replacement specified by $search and
+ * $replace arrays. Then strips any remaining HTML tags, reduces whitespace
+ * and newlines to a readable format, and word wraps the text to
+ * $width characters.
+ *
+ * @param string Reference to HTML content string
+ */
+ protected function _converter(&$text)
+ {
+ // Convert <BLOCKQUOTE> (before PRE!)
+ $this->_convert_blockquotes($text);
+
+ // Convert <PRE>
+ $this->_convert_pre($text);
+
+ // Run our defined tags search-and-replace
+ $text = preg_replace($this->search, $this->replace, $text);
+
+ // Run our defined tags search-and-replace with callback
+ $text = preg_replace_callback($this->callback_search, array($this, 'tags_preg_callback'), $text);
+
+ // Strip any other HTML tags
+ $text = strip_tags($text, $this->allowed_tags);
+
+ // Run our defined entities/characters search-and-replace
+ $text = preg_replace($this->ent_search, $this->ent_replace, $text);
+
+ // Replace known html entities
+ $text = html_entity_decode($text, ENT_QUOTES, $this->charset);
+
+ // Remove unknown/unhandled entities (this cannot be done in search-and-replace block)
+ $text = preg_replace('/&([a-zA-Z0-9]{2,6}|#[0-9]{2,4});/', '', $text);
+
+ // Convert "|+|amp|+|" into "&", need to be done after handling of unknown entities
+ // This properly handles situation of "&amp;quot;" in input string
+ $text = str_replace('|+|amp|+|', '&', $text);
+
+ // Bring down number of empty lines to 2 max
+ $text = preg_replace("/\n\s+\n/", "\n\n", $text);
+ $text = preg_replace("/[\n]{3,}/", "\n\n", $text);
+
+ // remove leading empty lines (can be produced by eg. P tag on the beginning)
+ $text = ltrim($text, "\n");
+
+ // Wrap the text to a readable format
+ // for PHP versions >= 4.0.2. Default width is 75
+ // If width is 0 or less, don't wrap the text.
+ if ( $this->width > 0 ) {
+ $text = wordwrap($text, $this->width);
+ }
+ }
+
+ /**
+ * Helper function called by preg_replace() on link replacement.
+ *
+ * Maintains an internal list of links to be displayed at the end of the
+ * text, with numeric indices to the original point in the text they
+ * appeared. Also makes an effort at identifying and handling absolute
+ * and relative links.
+ *
+ * @param string $link URL of the link
+ * @param string $display Part of the text to associate number with
+ */
+ protected function _build_link_list( $link, $display )
+ {
+ if (!$this->_do_links || empty($link)) {
+ return $display;
+ }
+
+ // Ignored link types
+ if (preg_match('!^(javascript:|mailto:|#)!i', $link)) {
+ return $display;
+ }
+
+ if (preg_match('!^([a-z][a-z0-9.+-]+:)!i', $link)) {
+ $url = $link;
+ }
+ else {
+ $url = $this->url;
+ if (substr($link, 0, 1) != '/') {
+ $url .= '/';
+ }
+ $url .= "$link";
+ }
+
+ if (($index = array_search($url, $this->_link_list)) === false) {
+ $index = count($this->_link_list);
+ $this->_link_list[] = $url;
+ }
+
+ return $display . ' [' . ($index+1) . ']';
+ }
+
+ /**
+ * Helper function for PRE body conversion.
+ *
+ * @param string HTML content
+ */
+ protected function _convert_pre(&$text)
+ {
+ // get the content of PRE element
+ while (preg_match('/<pre[^>]*>(.*)<\/pre>/ismU', $text, $matches)) {
+ $this->pre_content = $matches[1];
+
+ // Run our defined tags search-and-replace with callback
+ $this->pre_content = preg_replace_callback($this->callback_search,
+ array($this, 'tags_preg_callback'), $this->pre_content);
+
+ // convert the content
+ $this->pre_content = sprintf('<div><br>%s<br></div>',
+ preg_replace($this->pre_search, $this->pre_replace, $this->pre_content));
+
+ // replace the content (use callback because content can contain $0 variable)
+ $text = preg_replace_callback('/<pre[^>]*>.*<\/pre>/ismU',
+ array($this, 'pre_preg_callback'), $text, 1);
+
+ // free memory
+ $this->pre_content = '';
+ }
+ }
+
+ /**
+ * Helper function for BLOCKQUOTE body conversion.
+ *
+ * @param string HTML content
+ */
+ protected function _convert_blockquotes(&$text)
+ {
+ if (preg_match_all('/<\/*blockquote[^>]*>/i', $text, $matches, PREG_OFFSET_CAPTURE)) {
+ $level = 0;
+ $diff = 0;
+ foreach ($matches[0] as $m) {
+ if ($m[0][0] == '<' && $m[0][1] == '/') {
+ $level--;
+ if ($level < 0) {
+ $level = 0; // malformed HTML: go to next blockquote
+ }
+ else if ($level > 0) {
+ // skip inner blockquote
+ }
+ else {
+ $end = $m[1];
+ $len = $end - $taglen - $start;
+ // Get blockquote content
+ $body = substr($text, $start + $taglen - $diff, $len);
+
+ // Set text width
+ $p_width = $this->width;
+ if ($this->width > 0) $this->width -= 2;
+ // Convert blockquote content
+ $body = trim($body);
+ $this->_converter($body);
+ // Add citation markers and create PRE block
+ $body = preg_replace('/((^|\n)>*)/', '\\1> ', trim($body));
+ $body = '<pre>' . htmlspecialchars($body) . '</pre>';
+ // Re-set text width
+ $this->width = $p_width;
+ // Replace content
+ $text = substr($text, 0, $start - $diff)
+ . $body . substr($text, $end + strlen($m[0]) - $diff);
+
+ $diff = $len + $taglen + strlen($m[0]) - strlen($body);
+ unset($body);
+ }
+ }
+ else {
+ if ($level == 0) {
+ $start = $m[1];
+ $taglen = strlen($m[0]);
+ }
+ $level ++;
+ }
+ }
+ }
+ }
+
+ /**
+ * Callback function for preg_replace_callback use.
+ *
+ * @param array PREG matches
+ * @return string
+ */
+ public function tags_preg_callback($matches)
+ {
+ switch (strtolower($matches[1])) {
+ case 'b':
+ case 'strong':
+ return $this->_toupper($matches[3]);
+ case 'th':
+ return $this->_toupper("\t\t". $matches[3] ."\n");
+ case 'h':
+ return $this->_toupper("\n\n". $matches[3] ."\n\n");
+ case 'a':
+ // Remove spaces in URL (#1487805)
+ $url = str_replace(' ', '', $matches[3]);
+ return $this->_build_link_list($url, $matches[4]);
+ }
+ }
+
+ /**
+ * Callback function for preg_replace_callback use in PRE content handler.
+ *
+ * @param array PREG matches
+ * @return string
+ */
+ public function pre_preg_callback($matches)
+ {
+ return $this->pre_content;
+ }
+
+ /**
+ * Strtoupper function with HTML tags and entities handling.
+ *
+ * @param string $str Text to convert
+ * @return string Converted text
+ */
+ private function _toupper($str)
+ {
+ // string can containg HTML tags
+ $chunks = preg_split('/(<[^>]*>)/', $str, null, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
+
+ // convert toupper only the text between HTML tags
+ foreach ($chunks as $idx => $chunk) {
+ if ($chunk[0] != '<') {
+ $chunks[$idx] = $this->_strtoupper($chunk);
+ }
+ }
+
+ return implode($chunks);
+ }
+
+ /**
+ * Strtoupper multibyte wrapper function with HTML entities handling.
+ *
+ * @param string $str Text to convert
+ * @return string Converted text
+ */
+ private function _strtoupper($str)
+ {
+ $str = html_entity_decode($str, ENT_COMPAT, $this->charset);
+ $str = mb_strtoupper($str);
+ $str = htmlspecialchars($str, ENT_COMPAT, $this->charset);
+
+ return $str;
+ }
+}