replace)
 *
 * @return string substituted string
 */
function replace_macros($s, $r) {
	$arr = array('template' => $s, 'params' => $r);
	call_hooks('replace_macros', $arr);
	$t = App::template_engine();
	$output = $t->replace_macros($arr['template'],$arr['params']);
	return $output;
}
/**
 * @brief Generates a random string.
 *
 * @param number $size
 * @param int $type
 *
 * @return string
 */
function random_string($size = 64, $type = RANDOM_STRING_HEX) {
	// generate a bit of entropy and run it through the whirlpool
	$s = hash('whirlpool', (string) rand() . uniqid(rand(),true) . (string) rand(),(($type == RANDOM_STRING_TEXT) ? true : false));
	$s = (($type == RANDOM_STRING_TEXT) ? str_replace("\n","",base64url_encode($s,true)) : $s);
	return(substr($s, 0, $size));
}
/**
 * @brief This is our primary input filter.
 *
 * The high bit hack only involved some old IE browser, forget which (IE5/Mac?)
 * that had an XSS attack vector due to stripping the high-bit on an 8-bit character
 * after cleansing, and angle chars with the high bit set could get through as markup.
 *
 * This is now disabled because it was interfering with some legitimate unicode sequences
 * and hopefully there aren't a lot of those browsers left.
 *
 * Use this on any text input where angle chars are not valid or permitted
 * They will be replaced with safer brackets. This may be filtered further
 * if these are not allowed either.
 *
 * @param string $string Input string
 *
 * @return string Filtered string
 */
function notags($string) {
	return(str_replace(array("<",">"), array('[',']'), $string));
//  High-bit filter no longer used
//	return(str_replace(array("<",">","\xBA","\xBC","\xBE"), array('[',']','','',''), $string));
}
/**
 * use this on "body" or "content" input where angle chars shouldn't be removed,
 * and allow them to be safely displayed.
 *
 * @param string $string
 *
 * @return string
 */
function escape_tags($string) {
	return(htmlspecialchars($string, ENT_COMPAT, 'UTF-8', false));
}
function z_input_filter($channel_id,$s,$type = 'text/bbcode') {
	if($type === 'text/bbcode')
		return escape_tags($s);
	if($type === 'text/markdown')
		return escape_tags($s);
	if($type == 'text/plain')
		return escape_tags($s);
	if($type == 'application/x-pdl')
		return escape_tags($s);
	if(App::$is_sys) {
		return $s;
	}
	$r = q("select account_id, account_roles, channel_pageflags from account left join channel on channel_account_id = account_id where channel_id = %d limit 1",
		intval($channel_id)
	);
	if($r) {
		if(($r[0]['account_roles'] & ACCOUNT_ROLE_ALLOWCODE) || ($r[0]['channel_pageflags'] & PAGE_ALLOWCODE)) {
			if(local_channel() && (get_account_id() == $r[0]['account_id'])) {
				return $s;
			}
		}
	}
	if($type === 'text/html')
		return purify_html($s);
	return escape_tags($s);
}
function purify_html($s, $allow_position = false) {
	require_once('library/HTMLPurifier.auto.php');
	require_once('include/html2bbcode.php');
/**
 * @FIXME this function has html output, not bbcode - so safely purify these
 * $s = html2bb_video($s);
 * $s = oembed_html2bbcode($s);
 */
	$config = HTMLPurifier_Config::createDefault();
	$config->set('Cache.DefinitionImpl', null);
	$config->set('Attr.EnableID', true);
	//Allow some custom data- attributes used by built-in libs.
	//In this way members which do not have allowcode set can still use the built-in js libs in webpages to some extent.
	$def = $config->getHTMLDefinition(true);
	//data- attributes used by the foundation library
	// f6 navigation
	//dropdown menu
	$def->info_global_attr['data-dropdown-menu'] = new HTMLPurifier_AttrDef_Text;
	//drilldown menu
	$def->info_global_attr['data-drilldown'] = new HTMLPurifier_AttrDef_Text;
	//accordion menu
	$def->info_global_attr['data-accordion-menu'] = new HTMLPurifier_AttrDef_Text;
	//responsive navigation
	$def->info_global_attr['data-responsive-menu'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-responsive-toggle'] = new HTMLPurifier_AttrDef_Text;
	//magellan
	$def->info_global_attr['data-magellan'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-magellan-target'] = new HTMLPurifier_AttrDef_Text;
	// f6 containers
	//accordion
	$def->info_global_attr['data-accordion'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-accordion-item'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-tab-content'] = new HTMLPurifier_AttrDef_Text;
	//dropdown
	$def->info_global_attr['data-dropdown'] = new HTMLPurifier_AttrDef_Text;
	//off-canvas
	$def->info_global_attr['data-off-canvas-wrapper'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-off-canvas'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-off-canvas-content'] = new HTMLPurifier_AttrDef_Text;
	//reveal
	$def->info_global_attr['data-reveal'] = new HTMLPurifier_AttrDef_Text;
	//tabs
	$def->info_global_attr['data-tabs'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-tabs-content'] = new HTMLPurifier_AttrDef_Text;
	// f6 media
	//orbit
	$def->info_global_attr['data-orbit'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-slide'] = new HTMLPurifier_AttrDef_Text;
	//tooltip
	$def->info_global_attr['data-tooltip'] = new HTMLPurifier_AttrDef_Text;
	// f6 plugins
	//abide - the use is pointless since we can't do anything with forms
	//equalizer
	$def->info_global_attr['data-equalizer'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-equalizer-watch'] = new HTMLPurifier_AttrDef_Text;
	//interchange - potentially dangerous since it can load content
	//toggler
	$def->info_global_attr['data-toggler'] = new HTMLPurifier_AttrDef_Text;
	//sticky
	$def->info_global_attr['data-sticky'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-sticky-container'] = new HTMLPurifier_AttrDef_Text;
	// f6 common
	$def->info_global_attr['data-options'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-toggle'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-close'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-open'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-position'] = new HTMLPurifier_AttrDef_Text;
	//data- attributes used by the bootstrap library
	$def->info_global_attr['data-dismiss'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-target'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-toggle'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-backdrop'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-keyboard'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-show'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-spy'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-offset'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-animation'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-container'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-delay'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-placement'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-title'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-trigger'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-content'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-trigger'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-parent'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-ride'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-slide-to'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-slide'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-interval'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-pause'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-wrap'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-offset-top'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-offset-bottom'] = new HTMLPurifier_AttrDef_Text;
	//some html5 elements
	//Block
	$def->addElement('section', 'Block', 'Flow', 'Common');
	$def->addElement('nav',     'Block', 'Flow', 'Common');
	$def->addElement('article', 'Block', 'Flow', 'Common');
	$def->addElement('aside',   'Block', 'Flow', 'Common');
	$def->addElement('header',  'Block', 'Flow', 'Common');
	$def->addElement('footer',  'Block', 'Flow', 'Common');
	//Inline
	$def->addElement('button',  'Inline', 'Inline', 'Common');
	if($allow_position) {
		$cssDefinition = $config->getCSSDefinition();
		$cssDefinition->info['position'] = new HTMLPurifier_AttrDef_Enum(array('absolute', 'fixed', 'relative', 'static', 'inherit'), false);
		$cssDefinition->info['left'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
			new HTMLPurifier_AttrDef_CSS_Length(),
			new HTMLPurifier_AttrDef_CSS_Percentage()
		));
		$cssDefinition->info['right'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
			new HTMLPurifier_AttrDef_CSS_Length(),
			new HTMLPurifier_AttrDef_CSS_Percentage()
		));
		$cssDefinition->info['top'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
			new HTMLPurifier_AttrDef_CSS_Length(),
			new HTMLPurifier_AttrDef_CSS_Percentage()
		));
		$cssDefinition->info['bottom'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
			new HTMLPurifier_AttrDef_CSS_Length(),
			new HTMLPurifier_AttrDef_CSS_Percentage()
		));
	}
	$purifier = new HTMLPurifier($config);
	return $purifier->purify($s);
}
/**
 * @brief generate a string that's random, but usually pronounceable.
 *
 * Used to generate initial passwords.
 *
 * @param int $len
 * @return string
 */
function autoname($len) {
	if ($len <= 0)
		return '';
	$vowels = array('a','a','ai','au','e','e','e','ee','ea','i','ie','o','ou','u');
	if (mt_rand(0, 5) == 4)
		$vowels[] = 'y';
	$cons = array(
			'b','bl','br',
			'c','ch','cl','cr',
			'd','dr',
			'f','fl','fr',
			'g','gh','gl','gr',
			'h',
			'j',
			'k','kh','kl','kr',
			'l',
			'm',
			'n',
			'p','ph','pl','pr',
			'qu',
			'r','rh',
			's','sc','sh','sm','sp','st',
			't','th','tr',
			'v',
			'w','wh',
			'x',
			'z','zh'
			);
	$midcons = array('ck','ct','gn','ld','lf','lm','lt','mb','mm', 'mn','mp',
				'nd','ng','nk','nt','rn','rp','rt');
	$noend = array('bl', 'br', 'cl','cr','dr','fl','fr','gl','gr',
				'kh', 'kl','kr','mn','pl','pr','rh','tr','qu','wh');
	$start = mt_rand(0, 2);
	if ($start == 0)
		$table = $vowels;
	else
		$table = $cons;
	$word = '';
	for ($x = 0; $x < $len; $x ++) {
		$r = mt_rand(0,count($table) - 1);
		$word .= $table[$r];
		if ($table == $vowels)
			$table = array_merge($cons, $midcons);
		else
			$table = $vowels;
	}
	$word = substr($word,0,$len);
	foreach ($noend as $noe) {
		if ((strlen($word) > 2) && (substr($word,-2) == $noe)) {
			$word = substr($word,0,-1);
			break;
		}
	}
	if (substr($word, -1) == 'q')
		$word = substr($word, 0, -1);
	return $word;
}
/**
 * @brief escape text ($str) for XML transport
 *
 * @param string $str
 * @return string Escaped text.
 */
function xmlify($str) {
	$buffer = '';
	if(is_array($str)) {
		// allow to fall through so we ge a PHP error, as the log statement will
		// probably get lost in the noise unless we're specifically looking for it.
		btlogger('xmlify called with array: ' . print_r($str,true), LOGGER_NORMAL, LOG_WARNING);
	}
	$len = mb_strlen($str);
	for($x = 0; $x < $len; $x ++) {
		$char = mb_substr($str,$x,1);
		switch( $char ) {
			case "\r" :
				break;
			case "&" :
				$buffer .= '&';
				break;
			case "'" :
				$buffer .= ''';
				break;
			case "\"" :
				$buffer .= '"';
				break;
			case '<' :
				$buffer .= '<';
				break;
			case '>' :
				$buffer .= '>';
				break;
			case "\n" :
				$buffer .= "\n";
				break;
			default :
				$buffer .= $char;
				break;
		}
	}
	$buffer = trim($buffer);
	return($buffer);
}
/**
 * @brief Undo an xmlify.
 *
 * Pass xml escaped text ($s), returns unescaped text.
 *
 * @param string $s
 *
 * @return string
 */
function unxmlify($s) {
	$ret = str_replace('&', '&', $s);
	$ret = str_replace(array('<', '>', '"', '''), array('<', '>', '"', "'"), $ret);
	return $ret;
}
/**
 * @brief Automatic pagination.
 *
 * To use, get the count of total items.
 * Then call App::set_pager_total($number_items);
 * Optionally call App::set_pager_itemspage($n) to the number of items to display on each page
 * Then call paginate($a) after the end of the display loop to insert the pager block on the page
 * (assuming there are enough items to paginate).
 * When using with SQL, the setting LIMIT %d, %d => App::$pager['start'],App::$pager['itemspage']
 * will limit the results to the correct items for the current page.
 * The actual page handling is then accomplished at the application layer.
 *
 * @param App &$a
 */
function paginate(&$a) {
	$o = '';
	$stripped = preg_replace('/(&page=[0-9]*)/','',App::$query_string);
//	$stripped = preg_replace('/&zid=(.*?)([\?&]|$)/ism','',$stripped);
	$stripped = str_replace('q=','',$stripped);
	$stripped = trim($stripped,'/');
	$pagenum = App::$pager['page'];
	$url = z_root() . '/' . $stripped;
	if(App::$pager['total'] > App::$pager['itemspage']) {
		$o .= '
'."\r\n";
	}
	return $o;
}
function alt_pager(&$a, $i, $more = '', $less = '') {
	if(! $more)
		$more = t('older');
	if(! $less)
		$less = t('newer');
	$stripped = preg_replace('/(&page=[0-9]*)/','',App::$query_string);
	$stripped = str_replace('q=','',$stripped);
	$stripped = trim($stripped,'/');
	//$pagenum = App::$pager['page'];
	$url = z_root() . '/' . $stripped;
	return replace_macros(get_markup_template('alt_pager.tpl'), array(
		'$has_less' => ((App::$pager['page'] > 1) ? true : false),
		'$has_more' => (($i > 0 && $i >= App::$pager['itemspage']) ? true : false),
		'$less' => $less,
		'$more' => $more,
		'$url' => $url,
		'$prevpage' => App::$pager['page'] - 1,
		'$nextpage' => App::$pager['page'] + 1,
	));
}
/**
 * @brief Generate a guaranteed unique (for this domain) item ID for ATOM.
 *
 * Safe from birthday paradox.
 *
 * @return string a unique id
 */
function item_message_id() {
	do {
		$dups = false;
		$hash = random_string();
		$mid = $hash . '@' . App::get_hostname();
		$r = q("SELECT id FROM item WHERE mid = '%s' LIMIT 1",
			dbesc($mid));
		if(count($r))
			$dups = true;
	} while($dups == true);
	return $mid;
}
/**
 * @brief Generate a guaranteed unique photo ID.
 *
 * Safe from birthday paradox.
 *
 * @return string a uniqe hash
 */
function photo_new_resource() {
	do {
		$found = false;
		$resource = hash('md5', uniqid(mt_rand(), true));
		$r = q("SELECT id FROM photo WHERE resource_id = '%s' LIMIT 1",
			dbesc($resource));
		if(count($r))
			$found = true;
	} while($found === true);
	return $resource;
}
/**
 * @brief
 *
 * for html,xml parsing - let's say you've got
 * an attribute foobar="class1 class2 class3"
 * and you want to find out if it contains 'class3'.
 * you can't use a normal sub string search because you
 * might match 'notclass3' and a regex to do the job is
 * possible but a bit complicated.
 *
 * pass the attribute string as $attr and the attribute you
 * are looking for as $s - returns true if found, otherwise false
 *
 * @param string $attr attribute string
 * @param string $s attribute you are looking for
 * @return boolean true if found
 */
function attribute_contains($attr, $s) {
	// remove quotes
	$attr = str_replace([ '"',"'" ],['',''],$attr);
	$a = explode(' ', $attr);
	if($a && in_array($s, $a))
		return true;
	return false;
}
/**
 * @brief Logging function for Hubzilla.
 *
 * Logging output is configured through Hubzilla's system config. The log file
 * is set in system logfile, log level in system loglevel and to enable logging
 * set system debugging.
 *
 * Available constants for log level are LOGGER_NORMAL, LOGGER_TRACE, LOGGER_DEBUG,
 * LOGGER_DATA and LOGGER_ALL.
 *
 * Since PHP5.4 we get the file, function and line automatically where the logger
 * was called, so no need to add it to the message anymore.
 *
 * @param string $msg Message to log
 * @param int $level A log level
 * @param int $priority - compatible with syslog
 */
function logger($msg, $level = LOGGER_NORMAL, $priority = LOG_INFO) {
	if(App::$module == 'setup' && is_writable('install.log')) {
		$debugging = true;
		$logfile = 'install.log';
		$loglevel = LOGGER_ALL;
	}
	else {
		$debugging = get_config('system', 'debugging');
		$loglevel  = intval(get_config('system', 'loglevel'));
		$logfile   = get_config('system', 'logfile');
	}
	if((! $debugging) || (! $logfile) || ($level > $loglevel))
		return;
	$where = '';
	// We require > 5.4 but leave the version check so that install issues (including version) can be logged
	if(version_compare(PHP_VERSION, '5.4.0') >= 0) {
		$stack = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
		$where = basename($stack[0]['file']) . ':' . $stack[0]['line'] . ':' . $stack[1]['function'] . ': ';
	}
	$s = datetime_convert() . ':' . log_priority_str($priority) . ':' . session_id() . ':' . $where . $msg . PHP_EOL;
	$pluginfo = array('filename' => $logfile, 'loglevel' => $level, 'message' => $s,'priority' => $priority, 'logged' => false);
	if(! (App::$module == 'setup'))
		call_hooks('logger',$pluginfo);
	if(! $pluginfo['logged'])
		@file_put_contents($pluginfo['filename'], $pluginfo['message'], FILE_APPEND);
}
/**
 * @brief like logger() but with a function backtrace to pinpoint certain classes
 * of problems which show up deep in the calling stack.
 *
 * @param string $msg Message to log
 * @param int $level A log level
 * @param int $priority - compatible with syslog
 */
function btlogger($msg, $level = LOGGER_NORMAL, $priority = LOG_INFO) {
	if(! defined('BTLOGGER_DEBUG_FILE'))
		define('BTLOGGER_DEBUG_FILE','btlogger.out');
	logger($msg, $level, $priority);
	if(file_exists(BTLOGGER_DEBUG_FILE) && is_writable(BTLOGGER_DEBUG_FILE)) {
		$stack = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
		$where = basename($stack[0]['file']) . ':' . $stack[0]['line'] . ':' . $stack[1]['function'] . ': ';
		$s = datetime_convert() . ':' . log_priority_str($priority) . ':' . session_id() . ':' . $where . $msg . PHP_EOL;
		@file_put_contents(BTLOGGER_DEBUG_FILE, $s, FILE_APPEND);
	}
	if(version_compare(PHP_VERSION, '5.4.0') >= 0) {
		$stack = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
		if($stack) {
			for($x = 1; $x < count($stack); $x ++) {
				$s = 'stack: ' . basename($stack[$x]['file']) . ':' . $stack[$x]['line'] . ':' . $stack[$x]['function'] . '()';
				logger($s,$level, $priority);
				if(file_exists(BTLOGGER_DEBUG_FILE) && is_writable(BTLOGGER_DEBUG_FILE)) {
					@file_put_contents(BTLOGGER_DEBUG_FILE, $s . PHP_EOL, FILE_APPEND);
				}
			}
		}
	}
}
function log_priority_str($priority) {
	$parr = array(
		LOG_EMERG   => 'LOG_EMERG',
		LOG_ALERT   => 'LOG_ALERT',
		LOG_CRIT    => 'LOG_CRIT',
		LOG_ERR     => 'LOG_ERR',
		LOG_WARNING => 'LOG_WARNING',
		LOG_NOTICE  => 'LOG_NOTICE',
		LOG_INFO    => 'LOG_INFO',
		LOG_DEBUG   => 'LOG_DEBUG'
	);
	if($parr[$priority])
		return $parr[$priority];
	return 'LOG_UNDEFINED';
}
/**
 * @brief This is a special logging facility for developers.
 *
 * It allows one to target specific things to trace/debug and is identical to
 * logger() with the exception of the log filename. This allows one to isolate
 * specific calls while allowing logger() to paint a bigger picture of overall
 * activity and capture more detail.
 *
 * If you find dlogger() calls in checked in code, you are free to remove them -
 * so as to provide a noise-free development environment which responds to events
 * you are targetting personally.
 *
 * @param string $msg Message to log
 * @param int $level A log level.
 */
function dlogger($msg, $level = 0) {
	// turn off logger in install mode
	if(App::$module == 'setup')
		return;
	$debugging = get_config('system','debugging');
	$loglevel  = intval(get_config('system','loglevel'));
	$logfile   = get_config('system','dlogfile');
	if((! $debugging) || (! $logfile) || ($level > $loglevel))
		return;
	$where = '';
	if(version_compare(PHP_VERSION, '5.4.0') >= 0) {
		$stack = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
		$where = basename($stack[0]['file']) . ':' . $stack[0]['line'] . ':' . $stack[1]['function'] . ': ';
	}
	@file_put_contents($logfile, datetime_convert() . ':' . session_id() . ' ' . $where . $msg . PHP_EOL, FILE_APPEND);
}
function profiler($t1,$t2,$label) {
	if(file_exists('profiler.out') && $t1 && t2)
		@file_put_contents('profiler.out', sprintf('%01.4f %s',$t2 - $t1,$label) . PHP_EOL, FILE_APPEND);
}
function activity_match($haystack,$needle) {
	if(($haystack === $needle) || ((basename($needle) === $haystack) && strstr($needle,NAMESPACE_ACTIVITY_SCHEMA)))
		return true;
	return false;
}
/**
 * @brief Pull out all #hashtags and @person tags from $s.
 *
 * We also get @person@domain.com - which would make
 * the regex quite complicated as tags can also
 * end a sentence. So we'll run through our results
 * and strip the period from any tags which end with one.
 *
 * @param string $s
 * @return Returns array of tags found, or empty array.
 */
function get_tags($s) {
	$ret = array();
	$match = array();
	// ignore anything in a code block
	$s = preg_replace('/\[code(.*?)\](.*?)\[\/code\]/sm','',$s);
	// ignore anything in [style= ]
	$s = preg_replace('/\[style=(.*?)\]/sm','',$s);
	// ignore anything in [color= ], because it may contain color codes which are mistaken for tags
	$s = preg_replace('/\[color=(.*?)\]/sm','',$s);
	// match any double quoted tags
	if(preg_match_all('/([@#]\"\;.*?\"\;)/',$s,$match)) {
		foreach($match[1] as $mtch) {
			$ret[] = $mtch;
		}
	}
	// Match full names against @tags including the space between first and last
	// We will look these up afterward to see if they are full names or not recognisable.
	// The lookbehind is used to prevent a match in the middle of a word
	// '=' needs to be avoided because when the replacement is made (in handle_tag()) it has to be ignored there
	// Feel free to allow '=' if the issue with '=' is solved in handle_tag()
	// added / ? and [ to avoid issues with hashchars in url paths
	// added ; to single word tags to allow emojis and other unicode character constructs in bbcode
	// (this would actually be nnnnn; but the ampersand will have been escaped to & by the time we see it.)
	if(preg_match_all('/(? $a['total']) ? 1 : (-1));
}
/**
 * @brief Quick and dirty quoted_printable encoding.
 *
 * @param string $s
 * @return string
 */
function qp($s) {
	return str_replace ("%", "=", rawurlencode($s));
}
function get_mentions($item,$tags) {
	$o = '';
	if(! count($tags))
		return $o;
	foreach($tags as $x) {
		if($x['ttype'] == TERM_MENTION) {
			$o .= "\t\t" . '$1 ' : ' $1 '), $s);
	$s = preg_replace("/\<(.*?)(src|href)=(.*?)\&\;(.*?)\>/ism",'<$1$2=$3&$4>',$s);
	return($s);
}
/**
 * @brief Replace media element using http url with https to a local redirector
 *  if using https locally.
 *
 * Looks for HTML tags containing src elements that are http when we're viewing an https page
 * Typically this throws an insecure content violation in the browser. So we redirect them
 * to a local redirector which uses https and which redirects to the selected content
 *
 * @param string $s
 * @returns string
 */
function sslify($s) {
	if (strpos(z_root(),'https:') === false)
		return $s;
	// By default we'll only sslify img tags because media files will probably choke.
	// You can set sslify_everything if you want - but it will likely white-screen if it hits your php memory limit.
	// The downside is that http: media files will likely be blocked by your browser
	// Complain to your browser maker
	$allow = get_config('system','sslify_everything');
	$pattern = (($allow) ? "/\<(.*?)src=\"(http\:.*?)\"(.*?)\>/" : "/\';
		for ($x = 0; $x < count($params['texts']); $x ++) {
			$s .= '
' . $params['texts'][$x] . ' ' . $params['icons'][$x] . ' ';
		}
	} else {
		$params['string'] = preg_replace_callback('/<(3+)/','preg_heart',$params['string']);
		$s = str_replace($params['texts'],$params['icons'],$params['string']);
	}
	$s = preg_replace_callback('//ism', 'smile_unshield', $s);
	return $s;
}
/**
 * @brief
 *
 * @param array $m
 * @return string
 */
function smile_shield($m) {
	return '';
}
function smile_unshield($m) {
	return base64special_decode($m[1]);
}
/**
 * @brief Expand <3333 to the correct number of hearts.
 *
 * @param array $x
 */
function preg_heart($x) {
	if (strlen($x[1]) == 1)
		return $x[0];
	$t = '';
	for($cnt = 0; $cnt < strlen($x[1]); $cnt ++)
		$t .= '
';
	$r =  str_replace($x[0],$t,$x[0]);
	return $r;
}
function day_translate($s) {
	$ret = str_replace(array('Monday','Tuesday','Wednesday','Thursday','Friday','Saturday','Sunday'),
		array( t('Monday'), t('Tuesday'), t('Wednesday'), t('Thursday'), t('Friday'), t('Saturday'), t('Sunday')),
		$s);
	$ret = str_replace(array('January','February','March','April','May','June','July','August','September','October','November','December'),
		array( t('January'), t('February'), t('March'), t('April'), t('May'), t('June'), t('July'), t('August'), t('September'), t('October'), t('November'), t('December')),
		$ret);
	return $ret;
}
/**
 * @brief normalises a string.
 *
 * @param string $url
 * @return string
 */
function normalise_link($url) {
	$ret = str_replace(array('https:', '//www.'), array('http:', '//'), $url);
	return(rtrim($ret, '/'));
}
/**
 * @brief Compare two URLs to see if they are the same.
 *
 * But ignore slight but hopefully insignificant differences such as if one
 * is https and the other isn't, or if one is www.something and the other
 * isn't - and also ignore case differences.
 *
 * @see normalise_link()
 *
 * @param string $a
 * @param string $b
 * @return true if the URLs match, otherwise false
 */
function link_compare($a, $b) {
	if (strcasecmp(normalise_link($a), normalise_link($b)) === 0)
		return true;
	return false;
}
// Given an item array, convert the body element from bbcode to html and add smilie icons.
// If attach is true, also add icons for item attachments
function unobscure(&$item) {
	if(array_key_exists('item_obscured',$item) && intval($item['item_obscured'])) {
		$key = get_config('system','prvkey');
		if($item['title'])
			$item['title'] = crypto_unencapsulate(json_decode($item['title'],true),$key);
		if($item['body'])
			$item['body'] = crypto_unencapsulate(json_decode($item['body'],true),$key);
		if(get_config('system','item_cache')) {
			q("update item set title = '%s', body = '%s', item_obscured = 0 where id = %d",
				dbesc($item['title']),
				dbesc($item['body']),
				intval($item['id'])
			);
		}
	}
}
function unobscure_mail(&$item) {
	if(array_key_exists('mail_obscured',$item) && intval($item['mail_obscured'])) {
		if($item['title'])
			$item['title'] = base64url_decode(str_rot47($item['title']));
		if($item['body'])
			$item['body'] = base64url_decode(str_rot47($item['body']));
	}
}
function theme_attachments(&$item) {
	$arr = json_decode($item['attach'],true);
	if(is_array($arr) && count($arr)) {
		$attaches = array();
		foreach($arr as $r) {
			$icon = getIconFromType($r['type']);
			$label = (($r['title']) ? urldecode(htmlspecialchars($r['title'], ENT_COMPAT, 'UTF-8')) : t('Unknown Attachment'));
			//some feeds provide an attachment where title an empty space
			if($label  == ' ')
				$label = t('Unknown Attachment');
			$title = t('Size') . ' ' . (($r['length']) ? userReadableSize($r['length']) : t('unknown'));
			require_once('include/channel.php');
			if(is_foreigner($item['author_xchan']))
				$url = $r['href'];
			else
				$url = z_root() . '/magic?f=&hash=' . $item['author_xchan'] . '&dest=' . $r['href'] . '/' . $r['revision'];
			//$s .= '
' . $icon . ' ';
			$attaches[] = array('label' => $label, 'url' => $url, 'icon' => $icon, 'title' => $title);
		}
		$s = replace_macros(get_markup_template('item_attach.tpl'), array(
			'$attaches' => $attaches
		));
	}
	return $s;
}
function format_categories(&$item,$writeable) {
	$s = '';
	$terms = get_terms_oftype($item['term'],TERM_CATEGORY);
	if($terms) {
		$categories = array();
		foreach($terms as $t) {
			$term = htmlspecialchars($t['term'],ENT_COMPAT,'UTF-8',false) ;
			if(! trim($term))
				continue;
			$removelink = (($writeable) ?  z_root() . '/filerm/' . $item['id'] . '?f=&cat=' . urlencode($t['term']) : '');
			$categories[] = array('term' => $term, 'writeable' => $writeable, 'removelink' => $removelink, 'url' => zid($t['url']));
		}
		$s = replace_macros(get_markup_template('item_categories.tpl'),array(
			'$remove' => t('remove category'),
			'$categories' => $categories
		));
	}
	return $s;
}
/**
 * @brief Add any hashtags which weren't mentioned in the message body, e.g. community tags
 *
 * @param[in] array &$item
 * @return string HTML link of hashtag
 */
function format_hashtags(&$item) {
	$s = '';
	$terms = get_terms_oftype($item['term'], array(TERM_HASHTAG,TERM_COMMUNITYTAG));
	if($terms) {
		foreach($terms as $t) {
			$term = htmlspecialchars($t['term'], ENT_COMPAT, 'UTF-8', false) ;
			if(! trim($term))
				continue;
			if(strpos($item['body'], $t['url']))
				continue;
			if($s)
				$s .= ' ';
			$s .= '#
' . $term . ' ';
		}
	}
	return $s;
}
function format_mentions(&$item) {
	$s = '';
	$terms = get_terms_oftype($item['term'],TERM_MENTION);
	if($terms) {
		foreach($terms as $t) {
			$term = htmlspecialchars($t['term'],ENT_COMPAT,'UTF-8',false) ;
			if(! trim($term))
				continue;
			if(strpos($item['body'], $t['url']))
				continue;
			if($s)
				$s .= ' ';
			$s .= '@
' . $term . ' ';
		}
	}
	return $s;
}
function format_filer(&$item) {
	$s = '';
	$terms = get_terms_oftype($item['term'],TERM_FILE);
	if($terms) {
		$categories = array();
		foreach($terms as $t) {
			$term = htmlspecialchars($t['term'],ENT_COMPAT,'UTF-8',false) ;
			if(! trim($term))
				continue;
			$removelink = z_root() . '/filerm/' . $item['id'] . '?f=&term=' . urlencode($t['term']);
			$categories[] = array('term' => $term, 'removelink' => $removelink);
		}
		$s = replace_macros(get_markup_template('item_filer.tpl'),array(
			'$remove' => t('remove from file'),
			'$categories' => $categories
		));
	}
	return $s;
}
function generate_map($coord) {
	$coord = trim($coord);
	$coord = str_replace(array(',','/','  '),array(' ',' ',' '),$coord);
	$arr = array('lat' => trim(substr($coord,0,strpos($coord,' '))), 'lon' => trim(substr($coord,strpos($coord,' ')+1)), 'html' => '');
	call_hooks('generate_map',$arr);
	return (($arr['html']) ? $arr['html'] : $coord);
}
function generate_named_map($location) {
	$arr = array('location' => $location, 'html' => '');
	call_hooks('generate_named_map',$arr);
	return (($arr['html']) ? $arr['html'] : $location);
}
function prepare_body(&$item,$attach = false) {
	call_hooks('prepare_body_init', $item);
	$s = '';
	$photo = '';
	$is_photo = ((($item['verb'] === ACTIVITY_POST) && ($item['obj_type'] === ACTIVITY_OBJ_PHOTO)) ? true : false);
	if($is_photo) {
		$object = json_decode($item['obj'],true);
		// if original photo width is <= 640px prepend it to item body
		if($object['link'][0]['width'] && $object['link'][0]['width'] <= 640) {
			$s .= '
' . $s;
		}
		// if original photo width is > 640px make it a cover photo
		if($object['link'][0]['width'] && $object['link'][0]['width'] > 640) {
			$scale = ((($object['link'][1]['width'] == 1024) || ($object['link'][1]['height'] == 1024)) ? 1 : 0);
			$photo = '
';
		}
	}
	$s .= prepare_text($item['body'],$item['mimetype'], false);
	$event = (($item['obj_type'] === ACTIVITY_OBJ_EVENT) ? format_event_obj($item['obj']) : false);
	$prep_arr = array(
		'item' => $item,
		'html' => $event ? $event['content'] : $s,
		'event' => $event['header'],
		'photo' => $photo
	);
	call_hooks('prepare_body', $prep_arr);
	$s = $prep_arr['html'];
	$photo = $prep_arr['photo'];
	$event = $prep_arr['event'];
	if(! $attach) {
		return $s;
	}
	if(strpos($s,'
') !== false && $item['coord']) {
		$x = generate_map(trim($item['coord']));
		if($x) {
			$s = preg_replace('/\
/','$0' . $x,$s);
		}
	}
	$attachments = theme_attachments($item);
	$writeable = ((get_observer_hash() == $item['owner_xchan']) ? true : false);
	$tags = format_hashtags($item);
	if($item['resource_type'])
		$mentions = format_mentions($item);
	$categories = format_categories($item,$writeable);
	if(local_channel() == $item['uid'])
		$filer = format_filer($item);
	$s = sslify($s);
	$prep_arr = array(
		'item' => $item,
		'photo' => $photo,
		'html' => $s,
		'event' => $event,
		'categories' => $categories,
		'folders' => $filer,
		'tags' => $tags,
		'mentions' => $mentions,
		'attachments' => $attachments
	);
	call_hooks('prepare_body_final', $prep_arr);
	unset($prep_arr['item']);
	return $prep_arr;
}
/**
 * @brief Given a text string, convert from bbcode to html and add smilie icons.
 *
 * @param string $text
 * @param sting $content_type (optional) default text/bbcode
 * @param boolean $cache (optional) default false
 *
 * @return string
 */
function prepare_text($text, $content_type = 'text/bbcode', $cache = false) {
	switch($content_type) {
		case 'text/plain':
			$s = escape_tags($text);
			break;
		case 'text/html':
			$s = $text;
			break;
		case 'text/markdown':
			$s = MarkdownExtra::defaultTransform($text);
			break;
		case 'application/x-pdl';
			$s = escape_tags($text);
			break;
		// No security checking is done here at display time - so we need to verify
		// that the author is allowed to use PHP before storing. We also cannot allow
		// importation of PHP text bodies from other sites. Therefore this content
		// type is only valid for web pages (and profile details).
		// It may be possible to provide a PHP message body which is evaluated on the
		// sender's site before sending it elsewhere. In that case we will have a
		// different content-type here.
		case 'application/x-php':
			ob_start();
			eval($text);
			$s = ob_get_contents();
			ob_end_clean();
			break;
		case 'text/bbcode':
		case '':
		default:
			require_once('include/bbcode.php');
			if(stristr($text,'[nosmile]'))
				$s = bbcode($text,false,true,$cache);
			else
				$s = smilies(bbcode($text,false,true,$cache));
			$s = zidify_links($s);
			break;
	}
//logger('prepare_text: ' . $s);
	return $s;
}
function create_export_photo_body(&$item) {
	if(($item['verb'] === ACTIVITY_POST) && ($item['obj_type'] === ACTIVITY_OBJ_PHOTO)) {
		$j = json_decode($item['obj'],true);
		if($j) {
			$item['body'] .= "\n\n" . (($j['body']) ? $j['body'] : $j['bbcode']);
			$item['sig'] = '';
		}
	}
}
/**
 * @brief Return atom link elements for all of our hubs.
 *
 * @return string
 */
function feed_hublinks() {
	$hub = get_config('system', 'huburl');
	$hubxml = '';
	if(strlen($hub)) {
		$hubs = explode(',', $hub);
		if(count($hubs)) {
			foreach($hubs as $h) {
				$h = trim($h);
				if(! strlen($h))
					continue;
				$hubxml .= '
' . "\n" ;
			}
		}
	}
	return $hubxml;
}
/**
 * @brief Return atom link elements for salmon endpoints
 *
 * @param string $nick
 * @return string
 */
function feed_salmonlinks($nick) {
	$salmon  = '
' . "\n" ;
	// old style links that status.net still needed as of 12/2010
	$salmon .= '  
' . "\n" ;
	$salmon .= '  
' . "\n" ;
	return $salmon;
}
function get_plink($item,$conversation_mode = true) {
	if($conversation_mode)
		$key = 'plink';
	else
		$key = 'llink';
	if(x($item,$key)) {
		return array(
			'href' => zid($item[$key]),
			'title' => t('Link to Source'),
		);
	}
	else {
		return false;
	}
}
function unamp($s) {
	return str_replace('&', '&', $s);
}
function layout_select($channel_id, $current = '') {
	$r = q("select mid, v from item left join iconfig on iconfig.iid = item.id
		where iconfig.cat = 'system' and iconfig.k = 'PDL' and item.uid = %d and item_type = %d ",
		intval($channel_id),
		intval(ITEM_TYPE_PDL)
	);
	if($r) {
		$empty_selected = (($current === false) ? ' selected="selected" ' : '');
		$options .= '
' . t('default') . ' ';
		foreach($r as $rr) {
			$selected = (($rr['mid'] == $current) ? ' selected="selected" ' : '');
			$options .= '
' . $rr['v'] . ' ';
		}
	}
	$o = replace_macros(get_markup_template('field_select_raw.tpl'), array(
		'$field'	=> array('layout_mid', t('Page layout'), $selected, t('You can create your own with the layouts tool'), $options)
	));
	return $o;
}
function mimetype_select($channel_id, $current = 'text/bbcode') {
	$x = array(
		'text/bbcode',
		'text/html',
		'text/markdown',
		'text/plain',
		'application/x-pdl'
	);
	if(App::$is_sys) {
		$x[] = 'application/x-php';
	}
	else {
		$r = q("select account_id, account_roles, channel_pageflags from account left join channel on account_id = channel_account_id where
			channel_id = %d limit 1",
			intval($channel_id)
		);
		if($r) {
			if(($r[0]['account_roles'] & ACCOUNT_ROLE_ALLOWCODE) || ($r[0]['channel_pageflags'] & PAGE_ALLOWCODE)) {
				if(local_channel() && get_account_id() == $r[0]['account_id']) {
					$x[] = 'application/x-php';
				}
			}
		}
	}
	foreach($x as $y) {
		$selected = (($y == $current) ? ' selected="selected" ' : '');
		$options .= '
' . $y . ' ';
	}
	$o = replace_macros(get_markup_template('field_select_raw.tpl'), array(
		'$field'	=> array('mimetype', t('Page content type'), $selected, '', $options)
	));
	return $o;
}
function engr_units_to_bytes ($size_str) {
	if(! $size_str)
		return $size_str;
	switch (substr(trim($size_str), -1)) {
		case 'M': case 'm': return (int)$size_str * 1048576;
		case 'K': case 'k': return (int)$size_str * 1024;
		case 'G': case 'g': return (int)$size_str * 1073741824;
		default: return $size_str;
	}
}
function base64url_encode($s, $strip_padding = true) {
	$s = strtr(base64_encode($s),'+/','-_');
	if($strip_padding)
		$s = str_replace('=','',$s);
	return $s;
}
function base64url_decode($s) {
	if(is_array($s)) {
		logger('base64url_decode: illegal input: ' . print_r(debug_backtrace(), true));
		return $s;
	}
	return base64_decode(strtr($s,'-_','+/'));
}
function base64special_encode($s, $strip_padding = true) {
	$s = strtr(base64_encode($s),'+/',',.');
	if($strip_padding)
		$s = str_replace('=','',$s);
	return $s;
}
function base64special_decode($s) {
	if(is_array($s)) {
		logger('base64url_decode: illegal input: ' . print_r(debug_backtrace(), true));
		return $s;
	}
	return base64_decode(strtr($s,',.','+/'));
}
/**
 * @brief Return a div to clear floats.
 *
 * @return string
 */
function cleardiv() {
	return '
';
}
function bb_translate_video($s) {
	$arr = array('string' => $s);
	call_hooks('bb_translate_video',$arr);
	return $arr['string'];
}
function html2bb_video($s) {
	$arr = array('string' => $s);
	call_hooks('html2bb_video',$arr);
	return $arr['string'];
}
/**
 * apply xmlify() to all values of array $val, recursively
 */
function array_xmlify($val) {
	if (is_bool($val)) return $val?"true":"false";
	if (is_array($val)) return array_map('array_xmlify', $val);
	return xmlify((string) $val);
}
function reltoabs($text, $base) {
	if (empty($base))
		return $text;
	$base = rtrim($base,'/');
	$base2 = $base . "/";
	// Replace links
	$pattern = "/
]*) href=\"(?!http|https|\/)([^\"]*)\"/";
	$replace = " ]*) href=\"(?!http|https)([^\"]*)\"/";
	$replace = " ]*) src=\"(?!http|https|\/)([^\"]*)\"/";
	$replace = "" => array(123xyz,246qyo,sxo33e);
 *
 * @param string $s
 * @return array
 */
function expand_acl($s) {
	$ret = array();
	if(strlen($s)) {
		$t = str_replace('<','',$s);
		$a = explode('>',$t);
		foreach($a as $aa) {
			if($aa)
				$ret[] = $aa;
		}
	}
	return $ret;
}
function acl2json($s) {
	$s = expand_acl($s);
	$s = json_encode($s);
	return $s;
}
/**
 * @brief When editing a webpage - a dropdown is needed to select a page layout
 *
 * On submit, the pdl_select value (which is the mid of an item with item_type = ITEM_TYPE_PDL)
 * is stored in the webpage's resource_id, with resource_type 'pdl'.
 *
 * Then when displaying a webpage, we can see if it has a pdl attached. If not we'll
 * use the default site/page layout.
 *
 * If it has a pdl we'll load it as we know the mid and pass the body through comanche_parser() which will generate the
 * page layout from the given description
 *
 * @FIXME - there is apparently a very similar function called layout_select; this one should probably take precedence
 * and the other should be checked for compatibility and removed
 *
 * @param int $uid
 * @param string $current
 * @return string HTML code for dropdown
 */
function pdl_selector($uid, $current='') {
	$o = '';
	$sql_extra = item_permissions_sql($uid);
	$r = q("select iconfig.*, mid from item_id left join item on iconfig.iid = item.id
		where item.uid = %d and iconfig.cat = 'system' and iconfig.k = 'PDL' $sql_extra order by v asc",
		intval($uid)
	);
	$arr = array('channel_id' => $uid, 'current' => $current, 'entries' => $r);
	call_hooks('pdl_selector', $arr);
	$entries = $arr['entries'];
	$current = $arr['current'];
	$o .= '';
	$entries[] = array('title' => t('Default'), 'mid' => '');
	foreach($entries as $selection) {
		$selected = (($selection == $current) ? ' selected="selected" ' : '');
		$o .= "{$selection['v']} ";
	}
	$o .= ' ';
	return $o;
}
/**
 * @brief returns a one-dimensional array from a multi-dimensional array
 * empty values are discarded
 *
 * example: print_r(flatten_array_recursive(array('foo','bar',array('baz','blip',array('zob','glob')),'','grip')));
 *
 * Array ( [0] => foo [1] => bar [2] => baz [3] => blip [4] => zob [5] => glob [6] => grip )
 *
 * @param array $arr multi-dimensional array
 * @return one-dimensional array
 */
function flatten_array_recursive($arr) {
	$ret = array();
	if(! $arr)
		return $ret;
	foreach($arr as $a) {
		if(is_array($a)) {
			$tmp = flatten_array_recursive($a);
			if($tmp) {
				$ret = array_merge($ret, $tmp);
			}
		}
		elseif($a) {
			$ret[] = $a;
		}
	}
	return($ret);
}
/**
 * @brief Highlight Text.
 *
 * @param string $s Text to highlight
 * @param string $lang Which language should be highlighted
 * @return string
 */
function text_highlight($s, $lang) {
	if($lang === 'js')
		$lang = 'javascript';
	if($lang === 'json') {
		$lang = 'javascript';
		if(! strpos(trim($s), "\n"))
			$s = jindent($s);
	}
	if(! strpos('Text_Highlighter', get_include_path())) {
		set_include_path(get_include_path() . PATH_SEPARATOR . 'library/Text_Highlighter');
	}
	require_once('library/Text_Highlighter/Text/Highlighter.php');
	require_once('library/Text_Highlighter/Text/Highlighter/Renderer/Html.php');
	$options = array(
		'numbers' => HL_NUMBERS_LI,
		'tabsize' => 4,
	);
	$tag_added = false;
	$s = trim(html_entity_decode($s, ENT_COMPAT));
	$s = str_replace("    ", "\t", $s);
	// The highlighter library insists on an opening php tag for php code blocks. If
	// it isn't present, nothing is highlighted. So we're going to see if it's present.
	// If not, we'll add it, and then quietly remove it after we get the processed output back.
	if($lang === 'php') {
		if(strpos('setRenderer($renderer);
	$o = $hl->highlight($s);
	$o = str_replace(["    ", "\n"], ["    ", ''], $o);
	if($tag_added) {
		$b = substr($o, 0, strpos($o, ''));
		$e = substr($o, strpos($o, ' '));
		$o = $b . $e;
	}
	return('' . $o . '');
}
// function to convert multi-dimensional array to xml
// create new instance of simplexml
// $xml = new SimpleXMLElement('