<?php
/**
 * @file include/text.php
 */

require_once("include/template_processor.php");
require_once("include/smarty.php");

// random string, there are 86 characters max in text mode, 128 for hex
// output is urlsafe

define('RANDOM_STRING_HEX',  0x00 );
define('RANDOM_STRING_TEXT', 0x01 );

/**
 * @brief This is our template processor.
 *
 * @param string|FriendicaSmarty $s the string requiring macro substitution,
 *   or an instance of FriendicaSmarty
 * @param array $r key value pairs (search => replace)
 * @return string substituted string
 */
function replace_macros($s, $r) {
	$a = get_app();

	$arr = array('template' => $s, 'params' => $r);
	call_hooks('replace_macros', $arr);

	$t = $a->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);

	$a = get_app();
	if($a->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) {
	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
	$def->info_global_attr['data-options'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-magellan-expedition'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-magellan-destination'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-magellan-arrival'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-offcanvas'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-topbar'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-orbit'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-orbit-slide-number'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-dropdown'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-dropdown-content'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-reveal-id'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-reveal'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-alert'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-tooltip'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-joyride'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-id'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-text'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-class'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-prev-tex'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-button'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-accordion'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-tab'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-equalizer'] = new HTMLPurifier_AttrDef_Text;
	$def->info_global_attr['data-equalizer-watch'] = 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
	$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');

	$purifier = new HTMLPurifier($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 = '';

	$len = mb_strlen($str);
	for($x = 0; $x < $len; $x ++) {
		$char = mb_substr($str,$x,1);

		switch( $char ) {
			case "\r" :
				break;
			case "&" :
				$buffer .= '&amp;';
				break;
			case "'" :
				$buffer .= '&apos;';
				break;
			case "\"" :
				$buffer .= '&quot;';
				break;
			case '<' :
				$buffer .= '&lt;';
				break;
			case '>' :
				$buffer .= '&gt;';
				break;
			case "\n" :
				$buffer .= "\n";
				break;
			default :
				$buffer .= $char;
				break;
		}
	}
	$buffer = trim($buffer);

	return($buffer);
}

// undo an xmlify
// pass xml escaped text ($s), returns unescaped text


function unxmlify($s) {
	$ret = str_replace('&amp;','&', $s);
	$ret = str_replace(array('&lt;','&gt;','&quot;','&apos;'),array('<','>','"',"'"),$ret);
	return $ret;
}

/**
 * Convenience wrapper, reverse the operation "bin2hex"
 * This is a built-in function in php >= 5.4
 *
 * @FIXME We already have php >= 5.4 requirements, so can we remove this?
 */
if(! function_exists('hex2bin')) {
function hex2bin($s) {
	if(! (is_string($s) && strlen($s)))
		return '';

	if(strlen($s) & 1) {
		logger('hex2bin: illegal hex string: ' . $s);
		return $s;
	}

	if(! ctype_xdigit($s)) {
		return($s);
	}

	return(pack("H*",$s));
}}


// Automatic pagination.
// To use, get the count of total items.
// Then call $a->set_pager_total($number_items);
// Optionally call $a->set_pager_itemspage($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 => $a->pager['start'],$a->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. 


function paginate(&$a) {
	$o = '';
	$stripped = preg_replace('/(&page=[0-9]*)/','',$a->query_string);

//	$stripped = preg_replace('/&zid=(.*?)([\?&]|$)/ism','',$stripped);

	$stripped = str_replace('q=','',$stripped);
	$stripped = trim($stripped,'/');
	$pagenum = $a->pager['page'];
	$url = $a->get_baseurl() . '/' . $stripped;

	if($a->pager['total'] > $a->pager['itemspage']) {
		$o .= '<div class="pager">';
		if($a->pager['page'] != 1)
			$o .= '<span class="pager_prev">'."<a href=\"$url".'&page='.($a->pager['page'] - 1).'">' . t('prev') . '</a></span> ';

		$o .=  "<span class=\"pager_first\"><a href=\"$url"."&page=1\">" . t('first') . "</a></span> ";

			$numpages = $a->pager['total'] / $a->pager['itemspage'];

			$numstart = 1;
			$numstop = $numpages;

			if($numpages > 14) {
				$numstart = (($pagenum > 7) ? ($pagenum - 7) : 1);
				$numstop = (($pagenum > ($numpages - 7)) ? $numpages : ($numstart + 14));
			}

		for($i = $numstart; $i <= $numstop; $i++){
			if($i == $a->pager['page'])
				$o .= '<span class="pager_current">'.(($i < 10) ? '&nbsp;'.$i : $i);
			else
				$o .= "<span class=\"pager_n\"><a href=\"$url"."&page=$i\">".(($i < 10) ? '&nbsp;'.$i : $i)."</a>";
			$o .= '</span> ';
		}

		if(($a->pager['total'] % $a->pager['itemspage']) != 0) {
			if($i == $a->pager['page'])
				$o .= '<span class="pager_current">'.(($i < 10) ? '&nbsp;'.$i : $i);
			else
				$o .= "<span class=\"pager_n\"><a href=\"$url"."&page=$i\">".(($i < 10) ? '&nbsp;'.$i : $i)."</a>";
			$o .= '</span> ';
		}

		$lastpage = (($numpages > intval($numpages)) ? intval($numpages)+1 : $numpages);
		$o .= "<span class=\"pager_last\"><a href=\"$url"."&page=$lastpage\">" . t('last') . "</a></span> ";

		if(($a->pager['total'] - ($a->pager['itemspage'] * $a->pager['page'])) > 0)
			$o .= '<span class="pager_next">'."<a href=\"$url"."&page=".($a->pager['page'] + 1).'">' . t('next') . '</a></span>';
		$o .= '</div>'."\r\n";
	}
	return $o;
}


function alt_pager(&$a, $i, $more = '', $less = '') {

	if(! $more)
		$more = t('older');
	if(! $less)
		$less = t('newer');

	$stripped = preg_replace('/(&page=[0-9]*)/','',$a->query_string);
	$stripped = str_replace('q=','',$stripped);
	$stripped = trim($stripped,'/');
	//$pagenum = $a->pager['page'];
	$url = $a->get_baseurl() . '/' . $stripped;

	return replace_macros(get_markup_template('alt_pager.tpl'), array(
		'$has_less' => (($a->pager['page'] > 1) ? true : false),
		'$has_more' => (($i > 0 && $i >= $a->pager['itemspage']) ? true : false),
		'$less' => $less,
		'$more' => $more,
		'$url' => $url,
		'$prevpage' => $a->pager['page'] - 1,
		'$nextpage' => $a->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 . '@' . get_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;
}


// 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

function attribute_contains($attr, $s) {
	$a = explode(' ', $attr);
	if(count($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.
 */

function logger($msg, $level = 0) {
	// turn off logger in install mode
	global $a;
	global $db;

	if(($a->module == 'install') || (! ($db && $db->connected)))
		return;

	$debugging = get_config('system', 'debugging');
	$loglevel  = intval(get_config('system', 'loglevel'));
	$logfile   = get_config('system', 'logfile');

	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'] . ': ';
	}

	$s = datetime_convert() . ':' . session_id() . ' ' . $where . $msg . PHP_EOL;
	$pluginfo = array('filename' => $logfile, 'loglevel' => $level, 'message' => $s,'logged' => false);

	call_hooks('logger',$pluginfo);

	if(! $pluginfo['logged'])
		@file_put_contents($logfile, $s, FILE_APPEND);
}

/**
 * @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
	global $a;
	global $db;

	if(($a->module == 'install') || (! ($db && $db->connected)))
		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;
}


// 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.
// 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('/([@#]\&quot\;.*?\&quot\;)/',$s,$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
	if(preg_match_all('/(?<![a-zA-Z0-9=\/\?])(@[^ \x0D\x0A,:?\[]+ [^ \x0D\x0A@,:?\[]+)/',$s,$match)) {
		foreach($match[1] as $mtch) {
			if(substr($mtch,-1,1) === '.')
				$ret[] = substr($mtch,0,-1);
			else
				$ret[] = $mtch;
		}
	}

	// Otherwise pull out single word tags. These can be @nickname, @first_last
	// and #hash tags.

	if(preg_match_all('/(?<![a-zA-Z0-9=\/\?])([@#][^ \x0D\x0A,;:?\[]+)/',$s,$match)) {
		foreach($match[1] as $mtch) {
			if(substr($mtch,-1,1) === '.')
				$mtch = substr($mtch,0,-1);
			// ignore strictly numeric tags like #1 or #^ bookmarks or ## double hash
			if((strpos($mtch,'#') === 0) && ( ctype_digit(substr($mtch,1)) || substr($mtch,1,1) === '^') || substr($mtch,1,1) === '#')
				continue;
			// or quote remnants from the quoted strings we already picked out earlier
			if(strpos($mtch,'&quot'))
				continue;

			$ret[] = $mtch;
		}
	}

	// bookmarks

	if(preg_match_all('/#\^\[(url|zrl)(.*?)\](.*?)\[\/(url|zrl)\]/',$s,$match,PREG_SET_ORDER)) {
		foreach($match as $mtch) {
			$ret[] = $mtch[0];
		}
	}

	// make sure the longer tags are returned first so that if two or more have common substrings
	// we'll replace the longest ones first. Otherwise the common substring would be found in
	// both strings and the string replacement would link both to the shorter strings and 
	// fail to link the longer string. Hubzilla github issue #378
 
	usort($ret,'tag_sort_length');

//	logger('get_tags: ' . print_r($ret,true));

	return $ret;
}

function tag_sort_length($a,$b) {
	if(mb_strlen($a) == mb_strlen($b))
		return 0;

	return((mb_strlen($b) < mb_strlen($a)) ? (-1) : 1);
}


function strip_zids($s) {
	return preg_replace('/[\?&]zid=(.*?)(&|$)/ism','$2',$s);
}


// quick and dirty quoted_printable encoding


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['type'] == TERM_MENTION) {
			$o .= "\t\t" . '<link rel="mentioned" href="' . $x['url'] . '" />' . "\r\n";
			$o .= "\t\t" . '<link rel="ostatus:attention" href="' . $x['url'] . '" />' . "\r\n";
		}
	}
	return $o;
}


function contact_block() {
	$o = '';
	$a = get_app();

	if(! $a->profile['uid'])
		return;

	if(! perm_is_allowed($a->profile['uid'],get_observer_hash(),'view_contacts'))
		return;

	$shown = get_pconfig($a->profile['uid'],'system','display_friend_count');

	if($shown === false)
		$shown = 25;
	if($shown == 0)
		return;

	$is_owner = ((local_channel() && local_channel() == $a->profile['uid']) ? true : false);
	$sql_extra = '';

	$abook_flags = " and abook_pending = 0 and abook_self = 0 ";

	if(! $is_owner) {
		$abook_flags .= " and abook_hidden = 0 ";
		$sql_extra = " and xchan_hidden = 0 ";
	}

	if((! is_array($a->profile)) || ($a->profile['hide_friends']))
		return $o;

	$r = q("SELECT COUNT(abook_id) AS total FROM abook left join xchan on abook_xchan = xchan_hash WHERE abook_channel = %d
		$abook_flags and xchan_orphan = 0 and xchan_deleted = 0 $sql_extra",
		intval($a->profile['uid'])
	);
	if(count($r)) {
		$total = intval($r[0]['total']);
	}
	if(! $total) {
		$contacts = t('No connections');
		$micropro = null;
	} else {
		
		$randfunc = db_getfunc('RAND');
	
		$r = q("SELECT abook.*, xchan.* FROM abook left join xchan on abook.abook_xchan = xchan.xchan_hash WHERE abook_channel = %d $abook_flags and abook_archived = 0 and xchan_orphan = 0 and xchan_deleted = 0 $sql_extra ORDER BY $randfunc LIMIT %d",
			intval($a->profile['uid']),
			intval($shown)
		);

		if(count($r)) {
			$contacts = sprintf( tt('%d Connection','%d Connections', $total),$total);
			$micropro = Array();
			foreach($r as $rr) {
				$rr['archived'] = (intval($rr['abook_archived']) ? true : false);
				$micropro[] = micropro($rr,true,'mpfriend');
			}
		}
	}

	$tpl = get_markup_template('contact_block.tpl');
	$o = replace_macros($tpl, array(
		'$contacts' => $contacts,
		'$nickname' => $a->profile['channel_address'],
		'$viewconnections' => t('View Connections'),
		'$micropro' => $micropro,
	));

	$arr = array('contacts' => $r, 'output' => $o);

	call_hooks('contact_block_end', $arr);
	return $o;
}


function chanlink_hash($s) {
	return z_root() . '/chanview?f=&hash=' . urlencode($s);
}

function chanlink_url($s) {
	return z_root() . '/chanview?f=&url=' . urlencode($s);
}


function chanlink_cid($d) {
	return z_root() . '/chanview?f=&cid=' . intval($d);
}

function magiclink_url($observer,$myaddr,$url) {
	return (($observer) 
		? z_root() . '/magic?f=&dest=' . $url . '&addr=' . $myaddr 
		: $url
	);
}


function micropro($contact, $redirect = false, $class = '', $textmode = false) {

	if($contact['click'])
		$url = '#';
	else
		$url = chanlink_hash($contact['xchan_hash']);

	return replace_macros(get_markup_template(($textmode)?'micropro_txt.tpl':'micropro_img.tpl'),array(
		'$click' => (($contact['click']) ? $contact['click'] : ''),
		'$class' => $class . (($contact['archived']) ? ' archived' : ''),
		'$url' => $url,
		'$photo' => $contact['xchan_photo_s'],
		'$name' => $contact['xchan_name'],
		'$title' => $contact['xchan_name'] . ' [' . $contact['xchan_addr'] . ']',
	));
}


function search($s,$id='search-box',$url='/search',$save = false) {
	$a = get_app();
	return replace_macros(get_markup_template('searchbox.tpl'),array(
		'$s' => $s,
		'$id' => $id,
		'$action_url' => $a->get_baseurl((stristr($url,'network')) ? true : false) . $url,
		'$search_label' => t('Search'),
		'$save_label' => t('Save'),
		'$savedsearch' => feature_enabled(local_channel(),'savedsearch')
	));
}


function searchbox($s,$id='search-box',$url='/search',$save = false) {
	return replace_macros(get_markup_template('searchbox.tpl'),array(
		'$s' => $s,
		'$id' => $id,
		'$action_url' => z_root() . '/' . $url,
		'$search_label' => t('Search'),
		'$save_label' => t('Save'),
		'$savedsearch' => feature_enabled(local_channel(),'savedsearch')
	));
}

function valid_email_regex($x){
	if(preg_match('/^[_a-zA-Z0-9\-\+]+(\.[_a-zA-Z0-9\-\+]+)*@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)+$/',$x))
		return true;
	return false;
}

function valid_email($x){
	if(get_config('system','disable_email_validation'))
		return true;

	return valid_email_regex($x);
}

/**
 * @brief Replace naked text hyperlink with HTML formatted hyperlink.
 *
 * @param string $s
 * @param boolean $me (optional) default false
 * @return string
 */
function linkify($s, $me = false) {
	$s = preg_replace("/(https?\:\/\/[a-zA-Z0-9\:\/\-\?\&\;\.\=\_\@\~\#\'\%\$\!\+\,\@]*)/", (($me) ? ' <a href="$1" rel="me" >$1</a>' : ' <a href="$1" >$1</a>'), $s);
	$s = preg_replace("/\<(.*?)(src|href)=(.*?)\&amp\;(.*?)\>/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\:.*?)\"(.*?)\>/" : "/\<img(.*?)src=\"(http\:.*?)\"(.*?)\>/" ); 

	$matches = null;
	$cnt = preg_match_all($pattern,$s,$matches,PREG_SET_ORDER);
	if ($cnt) {
		foreach ($matches as $match) {
			$filename = basename( parse_url($match[2], PHP_URL_PATH) );
			$s = str_replace($match[2],z_root() . '/sslify/' . $filename . '?f=&url=' . urlencode($match[2]),$s);
		}
	}

	return $s;
}


function get_poke_verbs() {
	// index is present tense verb
	// value is array containing past tense verb, translation of present, translation of past

	$arr = array(
		'poke' => array( 'poked', t('poke'), t('poked')),
		'ping' => array( 'pinged', t('ping'), t('pinged')),
		'prod' => array( 'prodded', t('prod'), t('prodded')),
		'slap' => array( 'slapped', t('slap'), t('slapped')),
		'finger' => array( 'fingered', t('finger'), t('fingered')),
		'rebuff' => array( 'rebuffed', t('rebuff'), t('rebuffed')),
	);

	call_hooks('poke_verbs', $arr);
	return $arr;
}

function get_mood_verbs() {

	$arr = array(
		'happy'      => t('happy'),
		'sad'        => t('sad'),
		'mellow'     => t('mellow'),
		'tired'      => t('tired'),
		'perky'      => t('perky'),
		'angry'      => t('angry'),
		'stupefied'  => t('stupified'),
		'puzzled'    => t('puzzled'),
		'interested' => t('interested'),
		'bitter'     => t('bitter'),
		'cheerful'   => t('cheerful'),
		'alive'      => t('alive'),
		'annoyed'    => t('annoyed'),
		'anxious'    => t('anxious'),
		'cranky'     => t('cranky'),
		'disturbed'  => t('disturbed'),
		'frustrated' => t('frustrated'),
		'depressed'  => t('depressed'),
		'motivated'  => t('motivated'),
		'relaxed'    => t('relaxed'),
		'surprised'  => t('surprised'),
	);

	call_hooks('mood_verbs', $arr);
	return $arr;
}

// Function to list all smilies, both internal and from addons
// Returns array with keys 'texts' and 'icons'
function list_smilies() {
	$a = get_app();
	$texts =  array( 
		'&lt;3', 
		'&lt;/3', 
		'&lt;\\3', 
		':-)', 
		';-)', 
		':-(', 
		':-P', 
		':-p', 
		':-"', 
		':-&quot;', 
		':-x', 
		':-X', 
		':-D', 
		'8-|', 
		'8-O', 
		':-O', 
		'\\o/', 
		'o.O', 
		'O.o', 
		'o_O', 
		'O_o', 
		":'(", 
		":-!", 
		":-/", 
		":-[", 
		"8-)",
		':beer', 
		':homebrew', 
		':coffee', 
		':facepalm',
		':like',
		':dislike',
		'red#matrix',
		'red#',
		'r#'
	);

	$icons = array(
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-heart.gif" alt="&lt;3" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-brokenheart.gif" alt="&lt;/3" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-brokenheart.gif" alt="&lt;\\3" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-smile.gif" alt=":-)" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-wink.gif" alt=";-)" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-frown.gif" alt=":-(" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-tongue-out.gif" alt=":-P" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-tongue-out.gif" alt=":-p" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-kiss.gif" alt=":-\"" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-kiss.gif" alt=":-\"" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-kiss.gif" alt=":-x" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-kiss.gif" alt=":-X" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-laughing.gif" alt=":-D" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-surprised.gif" alt="8-|" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-surprised.gif" alt="8-O" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-surprised.gif" alt=":-O" />',                
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-thumbsup.gif" alt="\\o/" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-Oo.gif" alt="o.O" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-Oo.gif" alt="O.o" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-Oo.gif" alt="o_O" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-Oo.gif" alt="O_o" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-cry.gif" alt=":\'(" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-foot-in-mouth.gif" alt=":-!" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-undecided.gif" alt=":-/" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-embarassed.gif" alt=":-[" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-cool.gif" alt="8-)" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/beer_mug.gif" alt=":beer" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/beer_mug.gif" alt=":homebrew" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/coffee.gif" alt=":coffee" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-facepalm.gif" alt=":facepalm" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/like.gif" alt=":like" />',
		'<img class="smiley" src="' . $a->get_baseurl() . '/images/dislike.gif" alt=":dislike" />',
		'<a href="http://getzot.com"><strong>red<img class="smiley bb_rm-logo" src="' . $a->get_baseurl() . '/images/rm-32.png" alt="' . urlencode('red#matrix') . '" />matrix</strong></a>',
		'<a href="http://getzot.com"><strong>red<img class="smiley bb_rm-logo" src="' . $a->get_baseurl() . '/images/rm-32.png" alt="' . urlencode('red#') . '" />matrix</strong></a>',
		'<a href="http://getzot.com"><strong>red<img class="smiley bb_rm-logo" src="' . $a->get_baseurl() . '/images/rm-32.png" alt="r#" />matrix</strong></a>'

	);

	$params = array('texts' => $texts, 'icons' => $icons);
	call_hooks('smilie', $params);

	return $params;
}
/**
 * @brief Replaces text emoticons with graphical images.
 *
 * It is expected that this function will be called using HTML text.
 * We will escape text between HTML pre and code blocks, and HTML attributes
 * (such as urls) from being processed.
 *
 * At a higher level, the bbcode [nosmile] tag can be used to prevent this 
 * function from being executed by the prepare_text() routine when preparing
 * bbcode source for HTML display.
 *
 * @param string $s
 * @param boolean $sample (optional) default false
 * @return string
 */
function smilies($s, $sample = false) {

	if(intval(get_config('system', 'no_smilies')) 
		|| (local_channel() && intval(get_pconfig(local_channel(), 'system', 'no_smilies'))))
		return $s;

	$s = preg_replace_callback('{<(pre|code)>.*?</\1>}ism', 'smile_shield', $s);
	$s = preg_replace_callback('/<[a-z]+ .*?>/ism', 'smile_shield', $s);

	$params = list_smilies();
	$params['string'] = $s;

	if ($sample) {
		$s = '<div class="smiley-sample">';
		for ($x = 0; $x < count($params['texts']); $x ++) {
			$s .= '<dl><dt>' . $params['texts'][$x] . '</dt><dd>' . $params['icons'][$x] . '</dd></dl>';
		}
	} else {
		$params['string'] = preg_replace_callback('/&lt;(3+)/','preg_heart',$params['string']);
		$s = str_replace($params['texts'],$params['icons'],$params['string']);
	}

	$s = preg_replace_callback('/<!--base64:(.*?)-->/ism', 'smile_unshield', $s);

	return $s;
}

/**
 * @brief
 *
 * @param array $m
 * @return string
 */
function smile_shield($m) {
	return '<!--base64:' . base64url_encode($m[0]) . '-->';
}

function smile_unshield($m) { 
	return base64url_decode($m[1]); 
}

/**
 * @brief Expand <3333 to the correct number of hearts.
 *
 * @param array $x
 */
function preg_heart($x) {
	$a = get_app();
	if (strlen($x[1]) == 1)
		return $x[0];

	$t = '';
	for($cnt = 0; $cnt < strlen($x[1]); $cnt ++)
		$t .= '<img class="smiley" src="' . $a->get_baseurl() . '/images/smiley-heart.gif" alt="&lt;3" />';

	$r =  str_replace($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 normalis_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'])
			$item['title'] = crypto_unencapsulate(json_decode_plus($item['title']),$key);
		if($item['body'])
			$item['body'] = crypto_unencapsulate(json_decode_plus($item['body']),$key);
		if(get_config('system','item_cache')) {
			q("update item set title = '%s', body = '%s', item_obscured = 0 where id = %d",
				dbesc($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) {

	$arr = json_decode_plus($item['attach']);
	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/identity.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 .= '<a href="' . $url . '" title="' . $title . '" class="attachlink"  >' . $icon . '</a>';
			$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'], TERM_HASHTAG);
	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 .= '&nbsp';

			$s .= '#<a href="' . zid($t['url']) . '" >' . $term . '</a>';
		}
	}

	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 .= '&nbsp';

			$s .= '@<a href="' . zid($t['url']) . '" >' . $term . '</a>';
		}
	}

	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) {
	require_once('include/identity.php');

//	if($item['html']) {
//		$s = bb_observer($item['html']);
//	}
//	else {
		call_hooks('prepare_body_init', $item); 
//		unobscure($item);
		$s = prepare_text($item['body'],$item['mimetype'], false);
//	}


	$photo = '';
	$is_photo = (($item['obj_type'] === ACTIVITY_OBJ_PHOTO) ? true : false);

	if($is_photo) {
		$object = json_decode($item['object'],true);

		// if original photo width is <= 640px prepend it to item body
		if($object['link'][0]['width'] && $object['link'][0]['width'] <= 640) {
			$s = '<div class="inline-photo-item-wrapper"><a href="' . zid(rawurldecode($object['id'])) . '" target="_newwin"><img class="inline-photo-item" style="max-width:' . $object['link'][0]['width'] . 'px; width:100%; height:auto;" src="' . zid(rawurldecode($object['link'][0]['href'])) . '"></a></div>' . $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);
			$photo = '<a href="' . zid(rawurldecode($object['id'])) . '" target="_newwin"><img style="max-width:' . $object['link'][$scale]['width'] . 'px; width:100%; height:auto;" src="' . zid(rawurldecode($object['link'][$scale]['href'])) . '"></a>';
		}
	}

	$prep_arr = array(
		'item' => $item,
		'html' => $s,
		'photo' => $photo
	);

	call_hooks('prepare_body', $prep_arr);

	$s = $prep_arr['html'];
	$photo = $prep_arr['photo'];

//	q("update item set html = '%s' where id = %d",
//		dbesc($s),
//		intval($item['id'])
//	);

	if(! $attach) {
		return $s;
	}

	if(strpos($s,'<div class="map">') !== false && $item['coord']) {
		$x = generate_map(trim($item['coord']));
		if($x) {
			$s = preg_replace('/\<div class\=\"map\"\>/','$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);

	// Look for spoiler
	$spoilersearch = '<blockquote class="spoiler">';

	// Remove line breaks before the spoiler
	while ((strpos($s, "\n".$spoilersearch) !== false))
		$s = str_replace("\n".$spoilersearch, $spoilersearch, $s);
	while ((strpos($s, "<br />".$spoilersearch) !== false))
		$s = str_replace("<br />".$spoilersearch, $spoilersearch, $s);

	while ((strpos($s, $spoilersearch) !== false)) {

		$pos = strpos($s, $spoilersearch);
		$rnd = random_string(8);
		$spoilerreplace = '<br /> <span id="spoiler-wrap-'.$rnd.'" style="white-space:nowrap;" class="fakelink" onclick="openClose(\'spoiler-'.$rnd.'\');">'.sprintf(t('Click to open/close')).'</span>'.
                                '<blockquote class="spoiler" id="spoiler-'.$rnd.'" style="display: none;">';
		$s = substr($s, 0, $pos).$spoilerreplace.substr($s, $pos+strlen($spoilersearch));
	}

	// Look for quote with author
	$authorsearch = '<blockquote class="author">';

	while ((strpos($s, $authorsearch) !== false)) {
		$pos = strpos($s, $authorsearch);
		$rnd = random_string(8);
		$authorreplace = '<br /> <span id="author-wrap-'.$rnd.'" style="white-space:nowrap;" class="fakelink" onclick="openClose(\'author-'.$rnd.'\');">'.sprintf(t('Click to open/close')).'</span>'.
                                '<blockquote class="author" id="author-'.$rnd.'" style="display: block;">';
		$s = substr($s, 0, $pos).$authorreplace.substr($s, $pos+strlen($authorsearch));
	}

	$prep_arr = array(
		'item' => $item,
		'photo' => $photo,
		'html' => $s,
		'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 $content_type
 * @return string
 */
function prepare_text($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':
			require_once('library/markdown.php');
			$s = Markdown($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;
}


/**
 * zidify_callback() and zidify_links() work together to turn any HTML a tags with class="zrl" into zid links
 * These will typically be generated by a bbcode '[zrl]' tag. This is done inside prepare_text() rather than bbcode()
 * because the latter is used for general purpose conversions and the former is used only when preparing text for
 * immediate display.
 *
 * Issues: Currently the order of HTML parameters in the text is somewhat rigid and inflexible.
 *    We assume it looks like \<a class="zrl" href="xxxxxxxxxx"\> and will not work if zrl and href appear in a different order.
 *
 * @param array $match
 * @return string
 */
function zidify_callback($match) {
	$is_zid = ((feature_enabled(local_channel(),'sendzid')) || (strpos($match[1],'zrl')) ? true : false);
	$replace = '<a' . $match[1] . ' href="' . (($is_zid) ? zid($match[2]) : $match[2]) . '"';			
	$x = str_replace($match[0],$replace,$match[0]);

	return $x;
}

function zidify_img_callback($match) {
	$is_zid = ((feature_enabled(local_channel(),'sendzid')) || (strpos($match[1],'zrl')) ? true : false);
	$replace = '<img' . $match[1] . ' src="' . (($is_zid) ? zid($match[2]) : $match[2]) . '"';

	$x = str_replace($match[0],$replace,$match[0]);

	return $x;
}


function zidify_links($s) {
	$s = preg_replace_callback('/\<a(.*?)href\=\"(.*?)\"/ism','zidify_callback',$s);
	$s = preg_replace_callback('/\<img(.*?)src\=\"(.*?)\"/ism','zidify_img_callback',$s);

	return $s;
}

/**
 * @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;

				$hubxml .= '<link rel="hub" href="' . xmlify($h) . '" />' . "\n" ;
			}
		}
	}

	return $hubxml;
}

/* return atom link elements for salmon endpoints */

function feed_salmonlinks($nick) {
	$a = get_app();

	$salmon  = '<link rel="salmon" href="' . xmlify($a->get_baseurl() . '/salmon/' . $nick) . '" />' . "\n" ;

	// old style links that status.net still needed as of 12/2010 

	$salmon .= '  <link rel="http://salmon-protocol.org/ns/salmon-replies" href="' . xmlify($a->get_baseurl() . '/salmon/' . $nick) . '" />' . "\n" ; 
	$salmon .= '  <link rel="http://salmon-protocol.org/ns/salmon-mention" href="' . xmlify($a->get_baseurl() . '/salmon/' . $nick) . '" />' . "\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('&amp;', '&', $s);
}

function layout_select($channel_id, $current = '') {
	$r = q("select mid,sid from item left join item_id on iid = item.id where service = 'PDL' and item.uid = item_id.uid and item_id.uid = %d and item_type = %d ",
		intval($channel_id),
		intval(ITEM_TYPE_PDL)
	);

	if($r) {
		$empty_selected = (($current === false) ? ' selected="selected" ' : '');
		$options .= '<option value="" ' . $empty_selected . '>' . t('default') . '</option>';
		foreach($r as $rr) {
			$selected = (($rr['mid'] == $current) ? ' selected="selected" ' : '');
			$options .= '<option value="' . $rr['mid'] . '"' . $selected . '>' . $rr['sid'] . '</option>';
		}
	}

	$o = replace_macros(get_markup_template('field_select_raw.tpl'), array(
		'$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'
	);

	$a = get_app();
	if($a->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 .= '<option name="' . $y . '"' . $selected . '>' . $y . '</option>';
	}

	$o = replace_macros(get_markup_template('field_select_raw.tpl'), array(
		'$field'	=> array('mimetype', t('Page content type'), $selected, '', $options)
	));

	return $o;
}


function lang_selector() {
	global $a;

	$langs = glob('view/*/hstrings.php');

	$lang_options = array();
	$selected = "";

	if(is_array($langs) && count($langs)) {
		$langs[] = '';
		if(! in_array('view/en/hstrings.php',$langs))
			$langs[] = 'view/en/';
		asort($langs);
		foreach($langs as $l) {
			if($l == '') {
				$lang_options[""] = t('default');
				continue;
			}
			$ll = substr($l,5);
			$ll = substr($ll,0,strrpos($ll,'/'));
			$selected = (($ll === $a->language && (x($_SESSION, 'language'))) ? $ll : $selected);
			$lang_options[$ll] = get_language_name($ll, $ll) . " ($ll)";
		}
	}

	$tpl = get_markup_template("lang_selector.tpl");
	$o = replace_macros($tpl, array(
		'$title' => t('Select an alternate language'),
		'$langs' => array($lang_options, $selected),
		
	));

	return $o;
}


function return_bytes ($size_str) {
	switch (substr ($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,'-_','+/'));
}

/**
 * @ Return a div to clear floats.
 *
 * @return string
 */
function cleardiv() {
	return '<div class="clear"></div>';
}


function bb_translate_video($s) {

	$matches = null;
	$r = preg_match_all("/\[video\](.*?)\[\/video\]/ism",$s,$matches,PREG_SET_ORDER);
	if($r) {
		foreach($matches as $mtch) {
			if((stristr($mtch[1],'youtube')) || (stristr($mtch[1],'youtu.be')))
				$s = str_replace($mtch[0],'[youtube]' . $mtch[1] . '[/youtube]',$s);
			elseif(stristr($mtch[1],'vimeo'))
				$s = str_replace($mtch[0],'[vimeo]' . $mtch[1] . '[/vimeo]',$s);
		}
	}
	return $s;
}

function html2bb_video($s) {

	$s = preg_replace('#<object[^>]+>(.*?)https?://www.youtube.com/((?:v|cp)/[A-Za-z0-9\-_=]+)(.*?)</object>#ism',
			'[youtube]$2[/youtube]', $s);

	$s = preg_replace('#<iframe[^>](.*?)https?://www.youtube.com/embed/([A-Za-z0-9\-_=]+)(.*?)</iframe>#ism',
			'[youtube]$2[/youtube]', $s);

	$s = preg_replace('#<iframe[^>](.*?)https?://player.vimeo.com/video/([0-9]+)(.*?)</iframe>#ism',
			'[vimeo]$2[/vimeo]', $s);

	return $s;
}

/**
 * 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 = "/<a([^>]*) href=\"(?!http|https|\/)([^\"]*)\"/";
	$replace = "<a\${1} href=\"" . $base2 . "\${2}\"";
	$text = preg_replace($pattern, $replace, $text);

	$pattern = "/<a([^>]*) href=\"(?!http|https)([^\"]*)\"/";
	$replace = "<a\${1} href=\"" . $base . "\${2}\"";
	$text = preg_replace($pattern, $replace, $text);

	// Replace images
	$pattern = "/<img([^>]*) src=\"(?!http|https|\/)([^\"]*)\"/";
	$replace = "<img\${1} src=\"" . $base2 . "\${2}\"";
	$text = preg_replace($pattern, $replace, $text);

	$pattern = "/<img([^>]*) src=\"(?!http|https)([^\"]*)\"/";
	$replace = "<img\${1} src=\"" . $base . "\${2}\"";
	$text = preg_replace($pattern, $replace, $text);

	// Done
	return $text;
}

function item_post_type($item) {
	switch($item['resource_type']) {
		case 'photo':
			$post_type = t('photo');
			break;
		case 'event':
			$post_type = t('event');
			break;
		default:
			$post_type = t('status');
			if($item['mid'] != $item['parent_mid'])
				$post_type = t('comment');
			break;
	}

	if(strlen($item['verb']) && (! activity_match($item['verb'],ACTIVITY_POST)))
		$post_type = t('activity');

	return $post_type;
}


function undo_post_tagging($s) {
	$matches = null;
	$cnt = preg_match_all('/([@#])(\!*)\[zrl=(.*?)\](.*?)\[\/zrl\]/ism',$s,$matches,PREG_SET_ORDER);
	if($cnt) {
		foreach($matches as $mtch) {
			$s = str_replace($mtch[0], $mtch[1] . $mtch[2] . str_replace(' ','_',$mtch[4]),$s);
		}
	}
	return $s;
}

function fix_mce_lf($s) {
	$s = str_replace("\r\n","\n",$s);
//	$s = str_replace("\n\n","\n",$s);
	return $s;
}


function protect_sprintf($s) {
	return(str_replace('%','%%',$s));
}


function is_a_date_arg($s) {
	$i = intval($s);
	if($i > 1900) {
		$y = date('Y');
		if($i <= $y+1 && strpos($s,'-') == 4) {
			$m = intval(substr($s,5));
			if($m > 0 && $m <= 12)
				return true;
		}
	}

	return false;
}

function legal_webbie($s) {
	if(! strlen($s))
		return '';

	$x = $s;
	do {
		$s = $x;
		$x = preg_replace('/^([^a-z])(.*?)/',"$2",$s);
	} while($x != $s);

	return preg_replace('/([^a-z0-9\-\_])/','',$x);
}


function check_webbie($arr) {

	$reservechan = get_config('system','reserved_channels');
	if(strlen($reservechan))
		$taken = explode(',', $reservechan);
	else
		$taken = array();

	$str = '';
	if(count($arr)) {
		foreach($arr as $x) {
			$y = legal_webbie($x);
			if(strlen($y)) {
				if($str)
					$str .= ',';
				$str .= "'" . dbesc($y) . "'";
			}
		}

		if(strlen($str)) {
			$r = q("select channel_address from channel where channel_address in ( $str ) ");
			if(count($r)) {
				foreach($r as $rr) {
					$taken[] = $rr['channel_address'];
				}
			}
			foreach($arr as $x) {
				$y = legal_webbie($x);
				if(! in_array($y,$taken)) {
					return $y;
				}
			}
		}
	}

	return '';
}


function ids_to_querystr($arr,$idx = 'id') {
	$t = array();
	if($arr) {
		foreach($arr as $x) {
			if(! in_array($x[$idx],$t)) {
				$t[] = $x[$idx];
			}
		}
	}
	return(implode(',', $t));
}

// Fetches xchan and hubloc data for an array of items with only an 
// author_xchan and owner_xchan. If $abook is true also include the abook info. 
// This is needed in the API to save extra per item lookups there.

function xchan_query(&$items,$abook = true,$effective_uid = 0) {
	$arr = array();
	if($items && count($items)) {

		if($effective_uid) {
			for($x = 0; $x < count($items); $x ++) {
				$items[$x]['real_uid'] = $items[$x]['uid'];
				$items[$x]['uid'] = $effective_uid;
			}
		}

		foreach($items as $item) {
			if($item['owner_xchan'] && (! in_array($item['owner_xchan'],$arr)))
				$arr[] = "'" . dbesc($item['owner_xchan']) . "'";
			if($item['author_xchan'] && (! in_array($item['author_xchan'],$arr)))
				$arr[] = "'" . dbesc($item['author_xchan']) . "'";
		}
	}
	if(count($arr)) {
		if($abook) {
			$chans = q("select * from xchan left join hubloc on hubloc_hash = xchan_hash left join abook on abook_xchan = xchan_hash and abook_channel = %d
				where xchan_hash in (" . protect_sprintf(implode(',', $arr)) . ") and hubloc_primary = 1",
				intval($item['uid'])
			);
		}
		else {
			$chans = q("select xchan.*,hubloc.* from xchan left join hubloc on hubloc_hash = xchan_hash
				where xchan_hash in (" . protect_sprintf(implode(',', $arr)) . ") and hubloc_primary = 1");
		}
		$xchans = q("select * from xchan where xchan_hash in (" . protect_sprintf(implode(',',$arr)) . ") and xchan_network in ('rss','unknown')");
		if(! $chans)
			$chans = $xchans;
		else
			$chans = array_merge($xchans,$chans); 
	}
	if($items && count($items) && $chans && count($chans)) {
		for($x = 0; $x < count($items); $x ++) {
			$items[$x]['owner'] = find_xchan_in_array($items[$x]['owner_xchan'],$chans);
			$items[$x]['author'] = find_xchan_in_array($items[$x]['author_xchan'],$chans);
		}
	}
}

function xchan_mail_query(&$item) {
	$arr = array();
	$chans = null;
	if($item) {
		if($item['from_xchan'] && (! in_array($item['from_xchan'],$arr)))
			$arr[] = "'" . dbesc($item['from_xchan']) . "'";
		if($item['to_xchan'] && (! in_array($item['to_xchan'],$arr)))
			$arr[] = "'" . dbesc($item['to_xchan']) . "'";
	}

	if(count($arr)) {
		$chans = q("select xchan.*,hubloc.* from xchan left join hubloc on hubloc_hash = xchan_hash
			where xchan_hash in (" . implode(',', $arr) . ") and hubloc_primary = 1");
	}
	if($chans) {
		$item['from'] = find_xchan_in_array($item['from_xchan'],$chans);
		$item['to']  = find_xchan_in_array($item['to_xchan'],$chans);
	}
}


function find_xchan_in_array($xchan,$arr) {
	if(count($arr)) {
		foreach($arr as $x) {
			if($x['xchan_hash'] === $xchan) {
				return $x;
			}
		}
	}
	return array();
}

function get_rel_link($j,$rel) {
	if(is_array($j) && ($j))
		foreach($j as $l)
			if(array_key_exists('rel',$l) && $l['rel'] === $rel && array_key_exists('href',$l))
				return $l['href'];

	return '';
}


// Lots of code to write here

function magic_link($s) {
	return $s;
}

// if $escape is true, dbesc() each element before adding quotes

function stringify_array_elms(&$arr,$escape = false) {
	for($x = 0; $x < count($arr); $x ++)
		$arr[$x] = "'" . (($escape) ? dbesc($arr[$x]) : $arr[$x]) . "'";
}

/**
 * Indents a flat JSON string to make it more human-readable.
 *
 * @param string $json The original JSON string to process.
 *
 * @return string Indented version of the original JSON string.
 */
function jindent($json) {

	$result    = '';
	$pos       = 0;
	$strLen    = strlen($json);
	$indentStr = '  ';
	$newLine   = "\n";
	$prevChar  = '';
	$outOfQuotes = true;

	for ($i=0; $i<=$strLen; $i++) {
		// Grab the next character in the string.
		$char = substr($json, $i, 1);

		// Are we inside a quoted string?
		if ($char == '"' && $prevChar != '\\') {
			$outOfQuotes = !$outOfQuotes;

		// If this character is the end of an element, 
		// output a new line and indent the next line.
		} else if(($char == '}' || $char == ']') && $outOfQuotes) {
			$result .= $newLine;
			$pos --;
			for ($j=0; $j<$pos; $j++) {
				$result .= $indentStr;
			}
		}

		// Add the character to the result string.
		$result .= $char;

		// If the last character was the beginning of an element, 
		// output a new line and indent the next line.
		if (($char == ',' || $char == '{' || $char == '[') && $outOfQuotes) {
			$result .= $newLine;
			if ($char == '{' || $char == '[') {
				$pos ++;
			}

			for ($j = 0; $j < $pos; $j++) {
				$result .= $indentStr;
			}
		}
		
		$prevChar = $char;
	}

	return $result;
}


function json_decode_plus($s) {
	$x = json_decode($s,true);
	if(! $x)
		$x = json_decode(str_replace(array('\\"','\\\\'),array('"','\\'),$s),true);

	return $x;
}

/**
 * @brief Creates navigation menu for webpage, layout, blocks, menu sites.
 *
 * @return string
 */
function design_tools() {

	$channel  = get_app()->get_channel();
	$sys = false;

	if(get_app()->is_sys && is_site_admin()) {
		require_once('include/identity.php');
		$channel = get_sys_channel();
		$sys = true;
	}

	$who = $channel['channel_address'];

	return replace_macros(get_markup_template('design_tools.tpl'), array(
		'$title' => t('Design Tools'),
		'$who' => $who,
		'$sys' => $sys,
		'$blocks' => t('Blocks'),
		'$menus' => t('Menus'),
		'$layout' => t('Layouts'),
		'$pages' => t('Pages')
	));
}

/* case insensitive in_array() */

function in_arrayi($needle, $haystack) {
	return in_array(strtolower($needle), array_map('strtolower', $haystack));
}

function normalise_openid($s) {
	return trim(str_replace(array('http://','https://'),array('',''),$s),'/');
}

// used in ajax endless scroll request to find out all the args that the master page was viewing.
// This was using $_REQUEST, but $_REQUEST also contains all your cookies. So we're restricting it 
// to $_GET and $_POST. 

function extra_query_args() {
	$s = '';
	if(count($_GET)) {
		foreach($_GET as $k => $v) {
			// these are request vars we don't want to duplicate
			if(! in_array($k, array('q','f','zid','page','PHPSESSID'))) {
				$s .= '&' . $k . '=' . urlencode($v);
			}
		}
	}
	if(count($_POST)) {
		foreach($_POST as $k => $v) {
			// these are request vars we don't want to duplicate
			if(! in_array($k, array('q','f','zid','page','PHPSESSID'))) {
				$s .= '&' . $k . '=' . urlencode($v);
			}
		}
	}
	return $s;
}

/**
 * @brief This function removes the tag $tag from the text $body and replaces it
 * with the appropiate link.
 *
 * @param App $a
 * @param[in,out] string &$body the text to replace the tag in
 * @param[in,out] string &$access_tag used to return tag ACL exclusions e.g. @!foo
 * @param[in,out] string &$str_tags string to add the tag to
 * @param int $profile_uid
 * @param string $tag the tag to replace
 * @param boolean $diaspora default false
 * @return boolean true if replaced, false if not replaced
 */
function handle_tag($a, &$body, &$access_tag, &$str_tags, $profile_uid, $tag, $diaspora = false) {

	$replaced = false;
	$r = null;
	$match = array();

	$termtype = ((strpos($tag,'#') === 0)   ? TERM_HASHTAG : TERM_UNKNOWN);
	$termtype = ((strpos($tag,'@') === 0)   ? TERM_MENTION : $termtype);
	$termtype = ((strpos($tag,'#^[') === 0) ? TERM_BOOKMARK : $termtype);

	//is it a hash tag? 
	if(strpos($tag,'#') === 0) {
		if(strpos($tag,'#^[') === 0) {
			if(preg_match('/#\^\[(url|zrl)(.*?)\](.*?)\[\/(url|zrl)\]/',$tag,$match)) {
				$basetag = $match[3];
				$url = ((substr($match[2],0,1) === '=') ? substr($match[2],1) : $match[3]);
				$replaced = true;
			}
		}
		// if the tag is already replaced...
		elseif((strpos($tag,'[zrl=')) || (strpos($tag,'[url='))) {
			//...do nothing
			return $replaced;
		}
		if($tag == '#getzot') {
			$basetag = 'getzot'; 
			$url = 'http://hubzilla.org';
			$newtag = '#[zrl=' . $url . ']' . $basetag . '[/zrl]';
			$body = str_replace($tag,$newtag,$body);
			$replaced = true;
		}
		if(! $replaced) {

			//base tag has the tags name only

			if((substr($tag,0,7) === '#&quot;') && (substr($tag,-6,6) === '&quot;')) {
				$basetag = substr($tag,7);
				$basetag = substr($basetag,0,-6);
			}
			else
				$basetag = str_replace('_',' ',substr($tag,1));

			//create text for link
			$url = $a->get_baseurl() . '/search?tag=' . rawurlencode($basetag);
			$newtag = '#[zrl=' . $a->get_baseurl() . '/search?tag=' . rawurlencode($basetag) . ']' . $basetag . '[/zrl]';
			//replace tag by the link. Make sure to not replace something in the middle of a word
			// The '=' is needed to not replace color codes if the code is also used as a tag
			// Much better would be to somehow completely avoiding things in e.g. [color]-tags.
			// This would allow writing things like "my favourite tag=#foobar".
			$body = preg_replace('/(?<![a-zA-Z0-9=])'.preg_quote($tag,'/').'/', $newtag, $body);
			$replaced = true;
		}
		//is the link already in str_tags?
		if(! stristr($str_tags,$newtag)) {
			//append or set str_tags
			if(strlen($str_tags))
				$str_tags .= ',';

			$str_tags .= $newtag;
		}
		return array('replaced' => $replaced, 'termtype' => $termtype, 'term' => $basetag, 'url' => $url, 'contact' => $r[0]);	
	}

	//is it a person tag? 

	if(strpos($tag,'@') === 0) {

		// The @! tag will alter permissions
		$exclusive = ((strpos($tag,'!') === 1 && (! $diaspora)) ? true : false);

		//is it already replaced?
		if(strpos($tag,'[zrl='))
			return $replaced;

		//get the person's name

		$name = substr($tag,(($exclusive) ? 2 : 1)); // The name or name fragment we are going to replace
		$newname = $name; // a copy that we can mess with 
		$tagcid = 0;

		$r = null;

		// is it some generated name?

		$forum = false;
		$trailing_plus_name = false;

		// @channel+ is a forum or network delivery tag

		if(substr($newname,-1,1) === '+') {
			$forum = true;
			$newname = substr($newname,0,-1);
		}

		// Here we're looking for an address book entry as provided by the auto-completer
		// of the form something+nnn where nnn is an abook_id or the first chars of xchan_hash


		// If there's a +nnn in the string make sure there isn't a space preceding it

		$t1 = strpos($newname,' ');
		$t2 = strrpos($newname,'+');

		if($t1 && $t2 && $t1 < $t2)
			$t2 = 0;

		if(($t2) && (! $diaspora)) {
			//get the id

			$tagcid = substr($newname,$t2 + 1);

			if(strrpos($tagcid,' '))
				$tagcid = substr($tagcid,0,strrpos($tagcid,' '));

			if(strlen($tagcid) < 16)
				$abook_id = intval($tagcid);
			//remove the next word from tag's name
			if(strpos($name,' ')) {
				$name = substr($name,0,strpos($name,' '));
			}

			if($abook_id) { // if there was an id
				// select channel with that id from the logged in user's address book
				$r = q("SELECT * FROM abook left join xchan on abook_xchan = xchan_hash 
					WHERE abook_id = %d AND abook_channel = %d LIMIT 1",
						intval($abook_id),
						intval($profile_uid)
				);
			}
			else {
				$r = q("SELECT * FROM xchan 
					WHERE xchan_hash like '%s%%' LIMIT 1",
						dbesc($tagcid)
				);
			}
		}

		if(! $r) {

			// look for matching names in the address book

			// Two ways to deal with spaces - double quote the name or use underscores
			// we see this after input filtering so quotes have been html entity encoded

			if((substr($name,0,6) === '&quot;') && (substr($name,-6,6) === '&quot;')) {
				$newname = substr($name,6);
				$newname = substr($newname,0,-6);
			}
			else
				$newname = str_replace('_',' ',$name);

			// do this bit over since we started over with $name

			if(substr($newname,-1,1) === '+') {
				$forum = true;
				$newname = substr($newname,0,-1);
			}

			//select someone from this user's contacts by name
			$r = q("SELECT * FROM abook left join xchan on abook_xchan = xchan_hash  
				WHERE xchan_name = '%s' AND abook_channel = %d LIMIT 1",
					dbesc($newname),
					intval($profile_uid)
			);

			if(! $r) {
				//select someone by attag or nick and the name passed in
				$r = q("SELECT * FROM abook left join xchan on abook_xchan = xchan_hash  
					WHERE xchan_addr like ('%s') AND abook_channel = %d LIMIT 1",
						dbesc(((strpos($newname,'@')) ? $newname : $newname . '@%')),
						intval($profile_uid)
				);
			}

			if(! $r) {
				// it's possible somebody has a name ending with '+', which we stripped off as a forum indicator
				// This is very rare but we want to get it right.

				$r = q("SELECT * FROM abook left join xchan on abook_xchan = xchan_hash  
					WHERE xchan_name = '%s' AND abook_channel = %d LIMIT 1",
						dbesc($newname . '+'),
						intval($profile_uid)
				);
				if($r)
					$trailing_plus_name = true;
			}
		}

		// $r is set if we found something

		$channel = get_app()->get_channel();

		if($r) {
			$profile = $r[0]['xchan_url'];
			$newname = $r[0]['xchan_name'];
			// add the channel's xchan_hash to $access_tag if exclusive
			if($exclusive) {
				$access_tag .= 'cid:' . $r[0]['xchan_hash'];
			}
		}
		else {

			// check for a group/collection exclusion tag			

			// note that we aren't setting $replaced even though we're replacing text.
			// This tag isn't going to get a term attached to it. It's only used for
			// access control. The link points to out own channel just so it doesn't look
			// weird - as all the other tags are linked to something. 

			if(local_channel() && local_channel() == $profile_uid) {
				require_once('include/group.php');
				$grp = group_byname($profile_uid,$name);

				if($grp) {
					$g = q("select hash from groups where id = %d and visible = 1 limit 1",
						intval($grp)
					);
					if($g && $exclusive) {
						$access_tag .= 'gid:' . $g[0]['hash'];
					}
					$channel = get_app()->get_channel();
					if($channel) {
						$newtag = '@' . (($exclusive) ? '!' : '') . '[zrl=' . z_root() . '/channel/' . $channel['channel_address'] . ']' . $newname . '[/zrl]';
						$body = str_replace('@' . (($exclusive) ? '!' : '') . $name, $newtag, $body);
					}
				}
			}
		}

		if(($exclusive) && (! $access_tag)) {
			$access_tag .= 'cid:' . $channel['channel_hash'];
		}

		// if there is an url for this channel

		if(isset($profile)) {
			$replaced = true;
			//create profile link
			$profile = str_replace(',','%2c',$profile);
			$url = $profile;
			$newtag = '@' . (($exclusive) ? '!' : '') . '[zrl=' . $profile . ']' . $newname	. (($forum &&  ! $trailing_plus_name) ? '+' : '') . '[/zrl]';
			$body = str_replace('@' . (($exclusive) ? '!' : '') . $name, $newtag, $body);
			//append tag to str_tags
			if(! stristr($str_tags,$newtag)) {
				if(strlen($str_tags))
					$str_tags .= ',';
				$str_tags .= $newtag;
			}
		}
	}

	return array('replaced' => $replaced, 'termtype' => $termtype, 'term' => $newname, 'url' => $url, 'contact' => $r[0]);
}

function linkify_tags($a, &$body, $uid, $diaspora = false) {
	$str_tags = '';
	$tagged = array();
	$results = array();

	$tags = get_tags($body);

	if(count($tags)) {
		foreach($tags as $tag) {
			$access_tag = '';

			// If we already tagged 'Robert Johnson', don't try and tag 'Robert'.
			// Robert Johnson should be first in the $tags array

			$fullnametagged = false;
			for($x = 0; $x < count($tagged); $x ++) {
				if(stristr($tagged[$x],$tag . ' ')) {
					$fullnametagged = true;
					break;
				}
			}
			if($fullnametagged)
				continue;

			$success = handle_tag($a, $body, $access_tag, $str_tags, ($uid) ? $uid : $a->profile_uid , $tag, $diaspora); 
			$results[] = array('success' => $success, 'access_tag' => $access_tag);
			if($success['replaced']) $tagged[] = $tag;
		}
	}

	return $results;
}

/**
 * @brief returns icon name for use with e.g. font-awesome based on mime-type.
 *
 * These are the the font-awesome names of version 3.2.1. The newer font-awesome
 * 4 has different names.
 *
 * @param string $type mime type
 * @return string
 * @todo rename to get_icon_from_type()
 */
function getIconFromType($type) {
	$iconMap = array(
		//Folder
		t('Collection') => 'icon-folder-close',
		'multipart/mixed' => 'icon-folder-close', //dirs in attach use this mime type
		//Common file
		'application/octet-stream' => 'icon-file-alt',
		//Text
		'text/plain' => 'icon-file-text-alt',
		'application/msword' => 'icon-file-text-alt',
		'application/pdf' => 'icon-file-text-alt',
		'application/vnd.oasis.opendocument.text' => 'icon-file-text-alt',
		'application/epub+zip' => 'icon-book',
		//Spreadsheet
		'application/vnd.oasis.opendocument.spreadsheet' => 'icon-table',
		'application/vnd.ms-excel' => 'icon-table',
		//Image
		'image/jpeg' => 'icon-picture',
		'image/png' => 'icon-picture',
		'image/gif' => 'icon-picture',
		'image/svg+xml' => 'icon-picture',
		//Archive
		'application/zip' => 'icon-archive',
		'application/x-rar-compressed' => 'icon-archive',
		//Audio
		'audio/mpeg' => 'icon-music',
		'audio/wav' => 'icon-music',
		'application/ogg' => 'icon-music',
		'audio/ogg' => 'icon-music',
		'audio/webm' => 'icon-music',
		'audio/mp4' => 'icon-music',
		//Video
		'video/quicktime' => 'icon-film',
		'video/webm' => 'icon-film',
		'video/mp4' => 'icon-film'
	);

	$iconFromType = 'icon-file-alt';

	if (array_key_exists($type, $iconMap)) {
		$iconFromType = $iconMap[$type];
	}

	return $iconFromType;
}

/**
 * @brief Returns a human readable formatted string for filesizes.
 *
 * @param int $size filesize in bytes
 * @return string human readable formatted filesize
 * @todo rename to user_readable_size()
 */
function userReadableSize($size) {
	$ret = '';
	if (is_numeric($size)) {
		$incr = 0;
		$k = 1024;
		$unit = array('bytes', 'KB', 'MB', 'GB', 'TB', 'PB');
		while (($size / $k) >= 1){
			$incr++;
			$size = round($size / $k, 2);
		}
		$ret = $size . ' ' . $unit[$incr];
	}

	return $ret;
}

function str_rot47($str) {
	return strtr($str,
		'!"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~',
		'PQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNO');
}


function string_replace($old,$new,&$s) {

	$x = str_replace($old,$new,$s);
	$replaced = false;
	if($x !== $s) {
		$replaced = true;
	}
	$s = $x;
	return $replaced;
}


function json_url_replace($old,$new,&$s) {

	$old = str_replace('/','\\/',$old);
	$new = str_replace('/','\\/',$new);

	$x = str_replace($old,$new,$s);
	$replaced = false;
	if($x !== $s) {
		$replaced = true;
	}
	$s = $x;
	return $replaced;
}
		

function item_url_replace($channel,&$item,$old,$new) {
	
	if($item['attach'])
		json_url_replace($old,$new,$item['attach']);
	if($item['object'])
		json_url_replace($old,$new,$item['object']);
	if($item['target'])
		json_url_replace($old,$new,$item['target']);

	if(string_replace($old,$new,$item['body'])) {
		$item['sig'] = base64url_encode(rsa_sign($item['body'],$channel['channel_prvkey']));
		$item['item_verified']  = 1;
	}

}