<?php
	# Mantis - a php based bugtracking system
	# Copyright (C) 2000 - 2002  Kenzaburo Ito - kenito@300baud.org
	# Copyright (C) 2002 - 2004  Mantis Team   - mantisbt-dev@lists.sourceforge.net
	# This program is distributed under the terms and conditions of the GPL
	# See the README and LICENSE files for details

	# --------------------------------------------------------
	# $Id: string_api.php,v 1.75.4.2.2.1.2.1 2006/02/03 03:56:33 thraxisp Exp $
	# --------------------------------------------------------

	$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 <br />
	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 .= '&nbsp;';
			}

			$lines[$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( $p_string, ' ' ) !== false ) {
			return "<nobr>$p_string</nobr>";
		} else {
			return $p_string;
		}
	}

	# --------------------
	# Similar to nl2br, but fixes up a problem where new lines are doubled between
	# <pre> tags.
	# additionally, wrap the text an $p_wrap character intervals if the config is set
	function string_nl2br( $p_string, $p_wrap = 100 ) {
		$p_string = nl2br( $p_string );

		# fix up eols within <pre> tags (#1146)
		$pre2 = array();
		preg_match_all("/<pre[^>]*?>(.|\n)*?<\/pre>/", $p_string, $pre1);
		for ( $x = 0; $x < count($pre1[0]); $x++ ) {
			$pre2[$x] = preg_replace("/<br[^>]*?>/", "", $pre1[0][$x]);
			# @@@ thraxisp - this may want to be replaced by html_entity_decode (or equivalent)
			#     if other encoded characters are a problem
			$pre2[$x] = preg_replace("/&nbsp;/", " ", $pre2[$x]);
			if ( ON == config_get( 'wrap_in_preformatted_text' ) ) {
				$pre2[$x] = preg_replace("/([^\n]{".$p_wrap."})(?!<\/pre>)/", "$1\n", $pre2[$x]);
			}
			$pre1[0][$x] = "/" . preg_quote($pre1[0][$x], "/") . "/";
		}

		return preg_replace( $pre1[0], $pre2, $p_string );
	}

	# --------------------
	# Prepare a 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 );
		$p_string = string_preserve_spaces_at_bol( $p_string );
		$p_string = string_nl2br( $p_string );

		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 string for display in rss
	function string_rss_links( $p_string ) {
		# rss can not start with &nbsp; 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 &nbsp; 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 ( $t_param !== "" ) {
				return $t_path . '?' . urlencode( $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 <a href="..."> 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 ) {
			$t_replace_with = '[CVS] <a href="'.$t_cvs_web.'\\1?rev=\\4" target="_new">\\1</a>\\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.
	function string_process_bug_link( $p_string, $p_include_anchor = true, $p_detail_info = true, $p_fqdn = false ) {
		$t_tag = config_get( 'bug_link_tag' );
		# bail if the link tag is blank
		if ( '' == $t_tag ) {
			return $p_string;
		}

		preg_match_all( '/(^|.+?)(?:(?<=^|\W)' . preg_quote($t_tag, '/') . '(\d+)|$)/s',
								$p_string, $t_matches, PREG_SET_ORDER );
		$t_result = '';

		if ( $p_include_anchor ) {
			foreach ( $t_matches as $t_match ) {
				$t_result .= $t_match[1];

				if ( isset( $t_match[2] ) ) {
					$t_bug_id = $t_match[2];
					if ( bug_exists( $t_bug_id ) ) {
						$t_result .= string_get_bug_view_link( $t_bug_id, null, $p_detail_info, $p_fqdn );
					} else {
						$t_result .= $t_bug_id;
					}
				}
			}
		} else {
			foreach ( $t_matches as $t_match ) {
				$t_result .= $t_match[1];

				if ( isset( $t_match[2] ) ) {
					$t_bug_id = $t_match[2];
					# We might as well create the link here even if the bug
					#  doesn't exist.  In the case above we don't 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_result .= string_get_bug_view_url_with_fqdn( $t_bug_id, null );
				}
			}
		}

		return $t_result;
	}

	# --------------------
	# 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.
	function string_process_bugnote_link( $p_string, $p_include_anchor = true, $p_detail_info = true, $p_fqdn = false ) {
		$t_tag = config_get( 'bugnote_link_tag' );
		# bail if the link tag is blank
		if ( '' == $t_tag ) {
			return $p_string;
		}

		preg_match_all( '/(^|.+?)(?:(?<=^|\W)' . preg_quote($t_tag) . '(\d+)|$)/s',
								$p_string, $t_matches, PREG_SET_ORDER );
		$t_result = '';

		if ( $p_include_anchor ) {
			foreach ( $t_matches as $t_match ) {
				$t_result .= $t_match[1];

				if ( isset( $t_match[2] ) ) {
					$t_bugnote_id = $t_match[2];
					if ( bugnote_exists( $t_bugnote_id ) ) {
						$t_bug_id = bugnote_get_field( $t_bugnote_id, 'bug_id' );
						if ( bug_exists( $t_bug_id ) ) {
							$t_result .= string_get_bugnote_view_link( $t_bug_id, $t_bugnote_id, null, $p_detail_info, $p_fqdn );
						} else {
							$t_result .= $t_bugnote_id;
						}
					}
				}
			}
		} else {
			foreach ( $t_matches as $t_match ) {
				$t_result .= $t_match[1];

				if ( isset( $t_match[2] ) ) {
					$t_bugnote_id = $t_match[2];
					$t_bug_id = bugnote_get_field( $t_bugnote_id, 'bug_id' );
					# We might as well create the link here even if the bug
					#  doesn't exist.  In the case above we don't 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_result .= string_get_bugnote_view_url_with_fqdn( $t_bug_id, $t_bugnote_id, null );
				}
			}
		}

		return $t_result;
	}

	#===================================
	# 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',
                                                                 "'<a href=\"'.rtrim('\\1','.').'\">\\1</a> [<a href=\"'.rtrim('\\1','.').'\" target=\"_blank\">^</a>]'",
                                                                 $p_string);
		if( $t_change_quotes ) {
			ini_set( 'magic_quotes_sybase', true );
		}

		# Set up a simple subset of RFC 822 email address parsing
		#  We don't allow domain literals or quoted strings
		#  We also don't allow the & character in domains even though the RFC
		#  appears to do so.  This was to prevent &gt; etc from being included.
		#  Note: we could use email_get_rfc822_regex() but it doesn't work well
		#  when applied to data that has already had entities inserted.
		#
		# bpfennig: '@' doesn't accepted anymore
		$t_atom = '[^\'@\'](?:[^()<>@,;:\\\".\[\]\000-\037\177 &]+)';

		# In order to avoid selecting URLs containing @ characters as email
		#  addresses we limit our selection to addresses that are preceded by:
		#  * the beginning of the string
		#  * a &lt; entity (allowing '<foo@bar.baz>')
		#  * whitespace
		#  * a : (allowing 'send email to:foo@bar.baz')
		#  * a \n, \r, or > (because newlines have been replaced with <br />
		#    and > isn't valid in URLs anyway
		#
		# At the end of the string we allow the opposite:
		#  * the end of the string
		#  * a &gt; entity
		#  * whitespace
		#  * a , character (allowing 'email foo@bar.baz, or ...')
		#  * a \n, \r, or <

		$p_string = preg_replace( '/(?<=^|&quot;|&lt;|[\s\:\>\n\r])('.$t_atom.'(?:\.'.$t_atom.')*\@'.$t_atom.'(?:\.'.$t_atom.')*)(?=$|&quot;|&gt;|[\s\,\<\n\r])/s',
								'<a href="mailto:\1">\1</a>',
								$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 &lt;b&gt; and converts is into corresponding
	# html <b> based on the configuration presets
	function string_restore_valid_html_tags( $p_string ) {
		$t_html_valid_tags = config_get( 'html_valid_tags' );

		if ( OFF === $t_html_valid_tags || is_blank( $t_html_valid_tags ) ) {
			return $p_string;
		}

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

		foreach ( $tags as $tag ) {
			if ( !is_blank( $tag ) ) {
				$tag = trim( $tag );
				$p_string = eregi_replace( "&lt;($tag)[[:space:]]*&gt;", "<\\1>", $p_string );
				$p_string = eregi_replace( "&lt;\/($tag)[[:space:]]*&gt;", "</\\1>", $p_string );
				$p_string = eregi_replace( "&lt;($tag)[[:space:]]*\/&gt;", "<\\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 = '<a href="';
			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 ) . '</a>';
		} 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 = '<a href="';
			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) . '</a>';
		} 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 . '#'. $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, $p_user_id ).'#'.$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 '<a href="' . string_get_bug_update_url( $p_bug_id, $p_user_id ) . '" title="' . $t_summary . '">' . bug_format_id( $p_bug_id ) . '</a>';
	}

	# --------------------
	# 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 '<a href="' . string_get_bug_report_url( $p_user_id ) . '">' . lang_get( 'report_bug_link' ) . '</a>';
	}

	# --------------------
	# 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 ) {
		$t_timestamp = db_unixtimestamp( $p_date );
		return date( config_get( 'complete_date_format' ), $t_timestamp );
	}

	# --------------------
	# 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, if the current PHP version supports it.
	function string_html_entities( $p_string ) {
		if ( php_version_at_least( '4.1.0' ) ) {
			return htmlentities( $p_string, ENT_COMPAT, lang_get( 'charset' ) );
		} else {
			return htmlentities( $p_string );
		}
	}

	# --------------------
	# Calls htmlspecialchars on the specified string, passing along
	# the current charset, if the current PHP version supports it.
	function string_html_specialchars( $p_string ) {
		if ( php_version_at_least( '4.1.0' ) ) {
			return htmlspecialchars( $p_string, ENT_COMPAT, lang_get( 'charset' ) );
		} else {
			return htmlspecialchars( $p_string );
		}
	}
	
	# --------------------
	# 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");
		if ($t_truncate_pos !== false ) {
			$t_string = substr($t_string, 0, $t_truncate_pos);
		}

		$t_truncate_pos = strpos($p_string, "\r");
		if ($t_truncate_pos !== false ) {
			$t_string = substr($t_string, 0, $t_truncate_pos);
		}

		return $t_string;
	}
?>
