# Mantis - a php based bugtracking system

# Copyright (C) 2000 - 2002  Kenzaburo Ito - kenito@300baud.org

# Copyright (C) 2002 - 2007  Mantis Team   - mantisbt-dev@lists.sourceforge.net

# Mantis is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 2 of the License, or

# (at your option) any later version.

#

# Mantis is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with Mantis.  If not, see <http://www.gnu.org/licenses/>.

	#------------------------------

	#   $Revision: 2643 $

	#     $Author: al $    

	#       $Date: 2009-06-18 19:06:27 -0400 (Thu, 18 Jun 2009) $  

	#------------------------------

	$t_core_dir = dirname( __FILE__ ).DIRECTORY_SEPARATOR;

	require_once( $t_core_dir . 'bug_api.php' );

	require_once( $t_core_dir . 'user_pref_api.php' );

	### String Processing API ###

	### --------------------

	# Preserve spaces at beginning of lines.

	# Lines must be separated by \n rather than 

	function string_preserve_spaces_at_bol( $p_string ) {

		$lines = explode( "\n", $p_string );

		$line_count = count( $lines );

		for ( $i = 0; $i < $line_count; $i++ ) {

			$count	= 0;

			$prefix	= '';

			$t_char = substr( $lines[$i], $count, 1 );

			$spaces = 0;

			while ( ( $t_char  == ' ' ) || ( $t_char == "\t" ) ) {

				if ( $t_char == ' ' )

					$spaces++;

				else

					$spaces += 4; // 1 tab = 4 spaces, can be configurable.

				$count++;

				$t_char = substr( $lines[$i], $count, 1 );

			}

			for ( $j = 0; $j < $spaces; $j++ ) {

				$prefix .= ' ';

			}

			$lines[$i] = $prefix . substr( $lines[$i], $count );

		}

		return implode( "\n", $lines );

	}

	# --------------------

	# Prepare a string to be printed without being broken into multiple lines

	function string_no_break( $p_string ) {

		if ( strpos( $p_string, ' ' ) !== false ) {

			return '' . $p_string . "";

		} else {

			return $p_string;

		}

	}

	# --------------------

	# Similar to nl2br, but fixes up a problem where new lines are doubled between

	# 
 tags.

	# additionally, wrap the text an $p_wrap character intervals if the config is set

	function string_nl2br( $p_string, $p_wrap = 100 ) {

		$output = '';

		$pieces = preg_split('/(<pre[^>]*>.*?<\/pre>)/is', $p_string, -1, PREG_SPLIT_DELIM_CAPTURE); 	

		if(isset($pieces[1])) 

		{

			foreach($pieces as $piece)

			{

				if(preg_match('/(<pre[^>]*>.*?<\/pre>)/is', $piece)) 

				{

					$piece = preg_replace("/<br[^>]*?>/", "", $piece);

					# @@@ thraxisp - this may want to be replaced by html_entity_decode (or equivalent)

					#     if other encoded characters are a problem

					$piece = preg_replace("/ /", " ", $piece);

					if ( ON == config_get( 'wrap_in_preformatted_text' ) ) {

						$output .= preg_replace('/([^\n]{'.$p_wrap.'})(?!<\/pre>)/', "$1\n", $piece);

					} else {

						$output .= $piece;

					}

				} else {

					$output .= nl2br($piece);

				}

			}

			return $output;

		} else {

			return nl2br($p_string);

		}

	}

	# --------------------

	# Prepare a multiple line string for display to HTML

	function string_display( $p_string ) {	

		$p_string = string_strip_hrefs( $p_string );

		$p_string = string_html_specialchars( $p_string );

		$p_string = string_restore_valid_html_tags( $p_string, /* multiline = */ true );

		$p_string = string_preserve_spaces_at_bol( $p_string );

		$p_string = string_nl2br( $p_string );

		return $p_string;

	}

	# --------------------

	# Prepare a single line string for display to HTML

	function string_display_line( $p_string ) {

		$p_string = string_strip_hrefs( $p_string );

		$p_string = string_html_specialchars( $p_string );

		$p_string = string_restore_valid_html_tags( $p_string, /* multiline = */ false );

		return $p_string;

	}

	# --------------------

	# Prepare a string for display to HTML and add href anchors for URLs, emails,

	#  bug references, and cvs references

	function string_display_links( $p_string ) {

		$p_string = string_display( $p_string );

		$p_string = string_insert_hrefs( $p_string );

		$p_string = string_process_bug_link( $p_string );

		$p_string = string_process_bugnote_link( $p_string );

		$p_string = string_process_cvs_link( $p_string );

		return $p_string;

	}

	# --------------------

	# Prepare a single line string for display to HTML and add href anchors for 

	# URLs, emails, bug references, and cvs references

	function string_display_line_links( $p_string ) {

		$p_string = string_display_line( $p_string );

		$p_string = string_insert_hrefs( $p_string );

		$p_string = string_process_bug_link( $p_string );

		$p_string = string_process_bugnote_link( $p_string );

		$p_string = string_process_cvs_link( $p_string );

		return $p_string;

	}

	# --------------------

	# Prepare a string for display in rss

	function string_rss_links( $p_string ) {

		# rss can not start with   which spaces will be replaced into by string_display().

		$t_string = trim( $p_string );

		# same steps as string_display_links() without the preservation of spaces since   is undefined in XML.

		$t_string = string_strip_hrefs( $t_string );

		$t_string = string_html_specialchars( $t_string );

		$t_string = string_restore_valid_html_tags( $t_string );

		$t_string = string_nl2br( $t_string );

		$t_string = string_insert_hrefs( $t_string );

		$t_string = string_process_bug_link( $t_string, /* anchor */ true, /* detailInfo */ false, /* fqdn */ true );

		$t_string = string_process_bugnote_link( $t_string, /* anchor */ true, /* detailInfo */ false, /* fqdn */ true );

		$t_string = string_process_cvs_link( $t_string );

		# another escaping to escape the special characters created by the generated links

		$t_string = string_html_specialchars( $t_string );

		return $t_string;

	}

	# --------------------

	# Prepare a string for plain text display in email

	function string_email( $p_string ) {

		$p_string = string_strip_hrefs( $p_string );

		return $p_string;

	}

	# --------------------

	# Prepare a string for plain text display in email and add URLs for bug

	#  links and cvs links

	function string_email_links( $p_string ) {

		$p_string = string_email( $p_string );

		$p_string = string_process_bug_link( $p_string, false );

		$p_string = string_process_bugnote_link( $p_string, false );

		$p_string = string_process_cvs_link( $p_string, false );

		return $p_string;

	}

	# --------------------

	# Process a string for display in a textarea box

	function string_textarea( $p_string ) {

		$p_string = string_html_specialchars( $p_string );

		return $p_string;

	}

	# --------------------

	# Process a string for display in a text box

	function string_attribute( $p_string ) {

		$p_string = string_html_specialchars( $p_string );

		return $p_string;

	}

	# --------------------

	# Process a string for inclusion in a URL as a GET parameter

	function string_url( $p_string ) {

		$p_string = rawurlencode( $p_string );

		return $p_string;

	}

	# --------------------

	# validate the url as part of this site before continuing

	function string_sanitize_url( $p_url ) {

		$t_url = strip_tags( urldecode( $p_url ) );

		if ( preg_match( '?http(s)*://?', $t_url ) > 0 ) { 

			// no embedded addresses

			if ( preg_match( '?^' . config_get( 'path' ) . '?', $t_url ) == 0 ) { 

				// url is ok if it begins with our path, if not, replace it

				$t_url = 'index.php';

			}

		}

		if ( $t_url == '' ) {

			$t_url = 'index.php';

		}

		// split and encode parameters

		if ( strpos( $t_url, '?' ) !== FALSE ) {

			list( $t_path, $t_param ) = split( '\?', $t_url, 2 );

			if ( !is_blank($t_param ) ) {

				$t_vals = array();

				parse_str( html_entity_decode( $t_param ), $t_vals );

				$t_param = '';

				foreach( $t_vals as $k => $v ) {

					if ( $t_param != '' ) {

						$t_param .= '&'; 

					}

					if ( is_array( $v ) ) {

						for ( $i = 0, $t_size = sizeof( $v ); $i < $t_size; $i++ ) {

							$t_param .= $k . urlencode( '[]' ) . '=' . urlencode( strip_tags( urldecode( $v[$i] ) ) );

							$t_param .= ( $i != $t_size - 1 ) ? '&' : '';

						}

					} else {

						$t_param .= "$k=" . urlencode( strip_tags( urldecode( $v ) ) );

					}

				}

				return $t_path . '?' . $t_param;

			} else {

				return $t_path;

			}

		} else {

			return $t_url;

		}

	}

	# --------------------

	# process the $p_string and convert filenames in the format

	#  cvs:filename.ext or cvs:filename.ext:n.nn to a html link

	# if $p_include_anchor is true, include an  tag,

	#  otherwise, just insert the URL as text

	function string_process_cvs_link( $p_string, $p_include_anchor=true ) {

		$t_cvs_web = config_get( 'cvs_web' );

		if ( $p_include_anchor ) {

			$t_replace_with = '[CVS] \\1\\5';

		} else {

			$t_replace_with = '[CVS] '.$t_cvs_web.'\\1?rev=\\4\\5';

		}

		return preg_replace( '/cvs:([^\.\s:,\?!<]+(\.[^\.\s:,\?!<]+)*)(:)?(\d\.[\d\.]+)?([\W\s])?/i',

							 $t_replace_with,

							 $p_string );

	}

	# --------------------

	# Process $p_string, looking for bug ID references and creating bug view

	#  links for them.

	#

	# Returns the processed string.

	#

	# If $p_include_anchor is true, include the href tag, otherwise just insert

	#  the URL

	#

	# The bug tag ('#' by default) must be at the beginning of the string or

	#  preceeded by a character that is not a letter, a number or an underscore

	#

	# if $p_include_anchor = false, $p_fqdn is ignored and assumed to true.

	$string_process_bug_link_callback = array();

	function string_process_bug_link( $p_string, $p_include_anchor = true, $p_detail_info = true, $p_fqdn = false ) {

		global $string_process_bug_link_callback;

		$t_tag = config_get( 'bug_link_tag' );

		# bail if the link tag is blank

		if ( '' == $t_tag || $p_string == '' ) {

			return $p_string;

		}

		if ( !isset( $string_process_bug_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] ) ) {

			if ($p_include_anchor) {

				$string_process_bug_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] = create_function('$p_array','

										if (bug_exists( (int)$p_array[2] ) ) { 

											return $p_array[1] . string_get_bug_view_link( (int)$p_array[2], null, ' . ($p_detail_info ? 'true' : 'false') . ', ' . ($p_fqdn ? 'true' : 'false') . ');

										} else {    	

											return $p_array[0];

										}

										');

			} else {

				$string_process_bug_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] = create_function('$p_array','

										# We might as well create the link here even if the bug

										#  doesnt exist.  In the case above we dont want to do

										#  the summary lookup on a non-existant bug.  But here, we

										#  can create the link and by the time it is clicked on, the

										#  bug may exist.			

										return $p_array[1] . string_get_bug_view_url_with_fqdn( (int)$p_array[2], null );

										');

			}

		}

		$p_string = preg_replace_callback( '/(^|[^\w&])' . preg_quote($t_tag, '/') . '(\d+)\b/', $string_process_bug_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn], $p_string);

		return $p_string;

	}

	# --------------------

	# Process $p_string, looking for bugnote ID references and creating bug view

	#  links for them.

	#

	# Returns the processed string.

	#

	# If $p_include_anchor is true, include the href tag, otherwise just insert

	#  the URL

	#

	# The bugnote tag ('~' by default) must be at the beginning of the string or

	#  preceeded by a character that is not a letter, a number or an underscore

	#

	# if $p_include_anchor = false, $p_fqdn is ignored and assumed to true.

	$string_process_bugnote_link_callback = array();

	function string_process_bugnote_link( $p_string, $p_include_anchor = true, $p_detail_info = true, $p_fqdn = false ) {

		global $string_process_bugnote_link_callback;

		$t_tag = config_get( 'bugnote_link_tag' );

		# bail if the link tag is blank

		if ( '' == $t_tag || $p_string == '' ) {

			return $p_string;

		}

		if ( !isset ( $string_process_bugnote_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] ) ) {

			if ($p_include_anchor) {

				$string_process_bugnote_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] = create_function('$p_array','

										if ( bugnote_exists( (int)$p_array[2] ) ) {

											$t_bug_id = bugnote_get_field( (int)$p_array[2], \'bug_id\' );

											if ( bug_exists( $t_bug_id ) ) {

												return $p_array[1] . string_get_bugnote_view_link( $t_bug_id, (int)$p_array[2], null, ' . ($p_detail_info ? 'true' : 'false') . ', ' . ($p_fqdn ? 'true' : 'false') . ' );

											} else {

												return $p_array[0];

											}

										} else {

											return $p_array[0];

										}

										');

			} else {

				$string_process_bugnote_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn] = create_function('$p_array','

										# We might as well create the link here even if the bug

										#  doesnt exist.  In the case above we dont want to do

										#  the summary lookup on a non-existant bug.  But here, we

										#  can create the link and by the time it is clicked on, the

										#  bug may exist.	

										$t_bug_id = bugnote_get_field( (int)$p_array[2], \'bug_id\' );

										if ( bug_exists( $t_bug_id ) ) {

											return $p_array[1] . string_get_bugnote_view_url_with_fqdn( $t_bug_id, (int)$p_array[2], null );

										} else {

											return $p_array[0];

										}

										');

			}

		}

		$p_string = preg_replace_callback( '/(^|[^\w])' . preg_quote($t_tag, '/') .'(\d+)\b/', $string_process_bugnote_link_callback[$p_include_anchor][$p_detail_info][$p_fqdn], $p_string);

		return $p_string;

	}

	#===================================

	# Tag Processing

	#===================================

	# --------------------

	# Detect URLs and email addresses in the string and replace them with href anchors

	function string_insert_hrefs( $p_string ) {

		if ( !config_get( 'html_make_links' ) ) {

			return $p_string;

		}

		$t_change_quotes = false;

		if( ini_get_bool( 'magic_quotes_sybase' ) ) {

			$t_change_quotes = true;

			ini_set( 'magic_quotes_sybase', false );

		}

		# Find any URL in a string and replace it by a clickable link

		$p_string = preg_replace( '/(([[:alpha:]][-+.[:alnum:]]*):\/\/(%[[:digit:]A-Fa-f]{2}|[-_.!~*\';\/?%^\\\\:@&={\|}+$#\(\),\[\][:alnum:]])+)/se',

                                                                 "'\\1 [^]'",

                                                                 $p_string);

		if( $t_change_quotes ) {

			ini_set( 'magic_quotes_sybase', true );

		}

		$p_string = preg_replace( '/\b' . email_regex_simple() . '\b/i',

								'\0',

								$p_string);

		return $p_string;

	}

	# --------------------

	# Detect href anchors in the string and replace them with URLs and email addresses

	function string_strip_hrefs( $p_string ) {

		# First grab mailto: hrefs.  We don't care whether the URL is actually

		# correct - just that it's inside an href attribute.

		$p_string = preg_replace( '/<a\s[^\>]*href="mailto:([^\"]+)"[^\>]*>[^\<]*<\/a>/si',

								'\1',

								$p_string);

		# Then grab any other href

		$p_string = preg_replace( '/<a\s[^\>]*href="([^\"]+)"[^\>]*>[^\<]*<\/a>/si',

								'\1',

								$p_string);

		return $p_string;

	}

	# --------------------

	# This function looks for text with htmlentities

	# like <b> and converts is into corresponding

	# html  based on the configuration presets

	function string_restore_valid_html_tags( $p_string, $p_multiline = true ) {

		$t_html_valid_tags = config_get( $p_multiline ? 'html_valid_tags' : 'html_valid_tags_single_line' );

		if ( OFF === $t_html_valid_tags || is_blank( $t_html_valid_tags ) ) {

			return $p_string;

		}

		$tags = explode( ',', $t_html_valid_tags );

		foreach ($tags as $key => $value) { 

           if ( !is_blank( $value ) ) {

           	$tags[$key] = trim($value); 

           }

          }

        $tags = implode( '|', $tags);

		$p_string = eregi_replace( '<(' . $tags . ')[[:space:]]*>', '<\\1>', $p_string );

		$p_string = eregi_replace( '<\/(' .$tags . ')[[:space:]]*>', '</\\1>', $p_string );

		$p_string = eregi_replace( '<(' . $tags . ')[[:space:]]*\/>', '<\\1 />', $p_string );

		return $p_string;

	}

	#===================================

	# Advanced/Simple page selection

	#===================================

	# --------------------

	# return the name of a bug page for the user

	#  account for the user preference and site override

	#

	# $p_action should be something like 'view', 'update', or 'report'

	# If $p_user_id is null or not specified, use the current user

	function string_get_bug_page( $p_action, $p_user_id=null ) {

		if ( null === $p_user_id ) {

			if ( auth_is_user_authenticated() ) {

				$p_user_id = auth_get_current_user_id();

			}

		}

		$g_show_action = config_get( 'show_' . $p_action );

		switch ( $g_show_action ) {

			case BOTH:

					if ( ( null !== $p_user_id ) &&

						 ( ON == user_pref_get_pref( $p_user_id, 'advanced_' . $p_action ) ) ) {

						return 'bug_' . $p_action . '_advanced_page.php';

					} else {

						return 'bug_' . $p_action . '_page.php';

					}

			case SIMPLE_ONLY:

					return 'bug_' . $p_action . '_page.php';

			case ADVANCED_ONLY:

					return 'bug_' . $p_action . '_advanced_page.php';

		}

	}

	# --------------------

	# return an href anchor that links to a bug VIEW page for the given bug

	#  account for the user preference and site override

	function string_get_bug_view_link( $p_bug_id, $p_user_id = null, $p_detail_info = true, $p_fqdn = false ) {

		if ( bug_exists( $p_bug_id ) ) {

			$t_link = '

			if ( $p_fqdn ) {

				$t_link .= config_get( 'path' );

			}

			$t_link .= string_get_bug_view_url( $p_bug_id, $p_user_id ) . '"';

			if ( $p_detail_info ) {

				$t_summary = string_attribute( bug_get_field( $p_bug_id, 'summary' ) );

				$t_status = string_attribute( get_enum_element( 'status', bug_get_field( $p_bug_id, 'status' ) ) );

				$t_link .=  ' title="[' . $t_status . '] ' . $t_summary . '"';

			}

			$t_link .= '>' . bug_format_id( $p_bug_id ) . '';

		} else {

			$t_link = bug_format_id( $p_bug_id );

		}

		return $t_link;

	}

	# --------------------

	# return an href anchor that links to a bug VIEW page for the given bug

	#  account for the user preference and site override

	function string_get_bugnote_view_link( $p_bug_id, $p_bugnote_id, $p_user_id = null, $p_detail_info = true, $p_fqdn = false ) {

		if ( bug_exists( $p_bug_id ) && bugnote_exists( $p_bugnote_id ) ) {

			$t_link = '

			if ( $p_fqdn ) {

				$t_link .= config_get( 'path' );

			}

			$t_link .= string_get_bugnote_view_url( $p_bug_id, $p_bugnote_id, $p_user_id ) . '"';

			if ( $p_detail_info ) {

				$t_reporter = string_attribute( user_get_name ( bugnote_get_field( $p_bugnote_id, 'reporter_id' ) ) );

				$t_update_date = string_attribute( date( config_get( 'normal_date_format' ), ( db_unixtimestamp( bugnote_get_field( $p_bugnote_id, 'last_modified' ) ) ) ) );

				$t_link .=  ' title="[' . $t_update_date . '] ' . $t_reporter . '"';

			}

			$t_link .= '>' . lang_get( 'bugnote' ) . ': ' . bugnote_format_id( $p_bugnote_id) . '';

		} else {

			$t_link = lang_get( 'bugnote' ) . ': ' . bugnote_format_id( $p_bugnote_id);

		}

		return $t_link;

	}

	# --------------------

	# return the name and GET parameters of a bug VIEW page for the given bug

	#  account for the user preference and site override

	function string_get_bug_view_url( $p_bug_id, $p_user_id = null ) {

		return 'view.php?id=' . $p_bug_id;

	}

	# --------------------

	# return the name and GET parameters of a bug VIEW page for the given bug

	#  account for the user preference and site override

	function string_get_bugnote_view_url( $p_bug_id, $p_bugnote_id, $p_user_id = null ) {

		return 'view.php?id=' . $p_bug_id . '#c'. $p_bugnote_id;

	}

	# --------------------

	# return the name and GET parameters of a bug VIEW page for the given bug

	#  account for the user preference and site override

	# The returned url includes the fully qualified domain, hence it is suitable to be included

	# in emails.

	function string_get_bugnote_view_url_with_fqdn( $p_bug_id, $p_bugnote_id, $p_user_id = null ) {

		return config_get( 'path' ) . string_get_bug_view_url( $p_bug_id, $p_user_id ).'#c'.$p_bugnote_id;

	}

	# --------------------

	# return the name and GET parameters of a bug VIEW page for the given bug

	#  account for the user preference and site override

	# The returned url includes the fully qualified domain, hence it is suitable to be included

	# in emails.

	function string_get_bug_view_url_with_fqdn( $p_bug_id, $p_user_id = null ) {

		return config_get( 'path' ) . string_get_bug_view_url( $p_bug_id, $p_user_id );

	}

	# --------------------

	# return the name of a bug VIEW page for the user

	#  account for the user preference and site override

	function string_get_bug_view_page( $p_user_id = null ) {

		return string_get_bug_page( 'view', $p_user_id );

	}

	# --------------------

	# return an href anchor that links to a bug UPDATE page for the given bug

	#  account for the user preference and site override

	function string_get_bug_update_link( $p_bug_id, $p_user_id = null ) {

		$t_summary = string_attribute( bug_get_field( $p_bug_id, 'summary' ) );

		return '' . bug_format_id( $p_bug_id ) . '';

	}

	# --------------------

	# return the name and GET parameters of a bug UPDATE page for the given bug

	#  account for the user preference and site override

	function string_get_bug_update_url( $p_bug_id, $p_user_id = null ) {

		return string_get_bug_update_page( $p_user_id ) . '?bug_id=' . $p_bug_id;

	}

	# --------------------

	# return the name of a bug UPDATE page for the user

	#  account for the user preference and site override

	function string_get_bug_update_page( $p_user_id = null ) {

		return string_get_bug_page( 'update', $p_user_id );

	}

	# --------------------

	# return an href anchor that links to a bug REPORT page for the given bug

	#  account for the user preference and site override

	function string_get_bug_report_link( $p_user_id = null ) {

		return '' . lang_get( 'report_bug_link' ) . '';

	}

	# --------------------

	# return the name and GET parameters of a bug REPORT page for the given bug

	#  account for the user preference and site override

	function string_get_bug_report_url( $p_user_id = null ) {

		return string_get_bug_report_page( $p_user_id );

	}

	# --------------------

	# return the name of a bug REPORT page for the user

	#  account for the user preference and site override

	function string_get_bug_report_page( $p_user_id = null ) {

		return string_get_bug_page( 'report', $p_user_id );

	}

	# --------------------

	# return the complete url link to checkin using the confirm_hash

	function string_get_confirm_hash_url( $p_user_id, $p_confirm_hash ) {

		$t_path = config_get( 'path' );

		return $t_path . "verify.php?id=" . string_url( $p_user_id ) . "&confirm_hash=" . string_url( $p_confirm_hash );

	}

	# --------------------

	# Return a string with the $p_character pattern repeated N times.

	# $p_character - pattern to repeat

	# $p_repeats - number of times to repeat.

	function string_repeat_char( $p_character, $p_repeats ) {

		return str_pad( '', $p_repeats, $p_character );

	}

	# --------------------

	# Format date for display

	function string_format_complete_date( $p_date ) {

		return date( config_get( 'complete_date_format' ), $p_date );

	}

	# --------------------

	# Shorten a string for display on a dropdown to prevent the page rendering too wide

	#  ref issues #4630, #5072, #5131

	function string_shorten( $p_string ) {

		$t_max = config_get( 'max_dropdown_length' );

		if ( ( strlen( $p_string ) > $t_max ) && ( $t_max > 0 ) ){

			$t_pattern = '/([\s|.|,|\-|_|\/|\?]+)/';

			$t_bits = preg_split( $t_pattern, $p_string, -1, PREG_SPLIT_DELIM_CAPTURE );

			$t_string = '';

			$t_last = $t_bits[ count( $t_bits ) - 1 ];

			$t_last_len = strlen( $t_last );

			foreach ( $t_bits as $t_bit ) {

				if ( ( strlen( $t_string ) + strlen( $t_bit ) + $t_last_len + 3 <= $t_max )

					|| ( strpos( $t_bit, '.,-/?' ) > 0 ) ) {

					$t_string .= $t_bit;

				} else {

					break;

				}

			}

			$t_string .= '...' . $t_last;

			return $t_string;

		} else {

			return $p_string;

		}

	}

	# --------------------

	# remap a field name to a string name (for sort filter)

	function string_get_field_name( $p_string ) {

		$t_map = array(

				'last_updated' => 'last_update',

				'id' => 'email_bug'

				);

		$t_string = $p_string;

		if ( isset( $t_map[ $p_string ] ) ) {

			$t_string = $t_map[ $p_string ];

		}

		return lang_get_defaulted( $t_string );

	}

	# --------------------

	# Calls htmlentities on the specified string, passing along

	# the current charset.

	function string_html_entities( $p_string ) {

		return htmlentities( $p_string, ENT_COMPAT, lang_get( 'charset' ) );

	}

	# --------------------

	# Calls htmlspecialchars on the specified string, passing along

	# the current charset, if the current PHP version supports it.

	function string_html_specialchars( $p_string ) {

		# achumakov: @ added to avoid warning output in unsupported codepages

		# e.g. 8859-2, windows-1257, Korean, which are treated as 8859-1.

		# This is VERY important for Eastern European, Baltic and Korean languages

		return preg_replace("/&(#[0-9]+|[a-z]+);/i", "&$;;", @htmlspecialchars( $p_string, ENT_COMPAT, lang_get( 'charset' ) ) );

	}

	# --------------------

	# Prepares a string to be used as part of header().

	function string_prepare_header( $p_string ) {

		$t_string = $p_string;

		$t_truncate_pos = strpos($p_string, "\n");