vichan/inc/functions.php

<?php

/*
 *  Copyright (c) 2010-2013 Tinyboard Development Group
 */

if (realpath($_SERVER['SCRIPT_FILENAME']) == str_replace('\\', '/', __FILE__)) {
	// You cannot request this file directly.
	exit;
}

require_once 'inc/display.php';
require_once 'inc/template.php';
require_once 'inc/database.php';
require_once 'inc/events.php';
require_once 'inc/lib/gettext/gettext.inc';

// the user is not currently logged in as a moderator
$mod = false;

register_shutdown_function('fatal_error_handler');
mb_internal_encoding('UTF-8');
loadConfig();

function loadConfig() {
	global $board, $config, $__ip, $debug, $__version;
	
	$error = function_exists('error') ? 'error' : 'basic_error_function_because_the_other_isnt_loaded_yet';
	
	reset_events();
	
	if (!isset($_SERVER['REMOTE_ADDR']))
		$_SERVER['REMOTE_ADDR'] = '0.0.0.0';
	
	$arrays = array(
		'db',
		'cache',
		'cookies',
		'error',
		'dir',
		'mod',
		'spam',
		'flood_filters',
		'wordfilters',
		'custom_capcode',
		'custom_tripcode',
		'dnsbl',
		'dnsbl_exceptions',
		'remote',
		'allowed_ext',
		'allowed_ext_files',
		'file_icons',
		'footer',
		'stylesheets',
		'additional_javascript',
		'markup',
		'custom_pages'
	);
	
	$config = array();
	foreach ($arrays as $key) {
		$config[$key] = array();
	}
	
	require 'inc/config.php';
	if (!file_exists('inc/instance-config.php'))
		$error('Tinyboard is not configured! Create inc/instance-config.php.');
	
	require 'inc/instance-config.php';
	
	if (isset($board['dir']) && file_exists($board['dir'] . '/config.php')) {
		require $board['dir'] . '/config.php';
	}
	
	if (!isset($__version))
		$__version = file_exists('.installed') ? trim(file_get_contents('.installed')) : false;
	$config['version'] = $__version;
	
	if ($config['debug']) {
		if (!isset($debug)) {
			$debug = array('sql' => array(), 'purge' => array(), 'cached' => array(), 'write' => array());
			$debug['start'] = microtime(true);
		}
	}
	
	date_default_timezone_set($config['timezone']);
	
	if (!isset($config['blotter']))
		$config['blotter'] = false;
	
	if (!isset($config['post_url']))
		$config['post_url'] = $config['root'] . $config['file_post'];
	
	if (!isset($config['referer_match']))
		if (isset($_SERVER['HTTP_HOST'])) {
			$config['referer_match'] = '/^' .
				(preg_match($config['url_regex'], $config['root']) ? '' :
					'https?:\/\/' . $_SERVER['HTTP_HOST']) .
					preg_quote($config['root'], '/') .
				'(' .
						str_replace('%s', $config['board_regex'], preg_quote($config['board_path'], '/')) .
						'(' .
							preg_quote($config['file_index'], '/') . '|' .
							str_replace('%d', '\d+', preg_quote($config['file_page'])) .
						')?' .
					'|' .
						str_replace('%s', $config['board_regex'], preg_quote($config['board_path'], '/')) .
						preg_quote($config['dir']['res'], '/') .
						str_replace('%d', '\d+', preg_quote($config['file_page'], '/')) .
					'|' .
						preg_quote($config['file_mod'], '/') . '\?\/.+' .
				')([#?](.+)?)?$/ui';
		} else {
			// CLI mode
			$config['referer_match'] = '//';
		}
	if (!isset($config['cookies']['path']))
		$config['cookies']['path'] = &$config['root'];
		
	if (!isset($config['dir']['static']))
		$config['dir']['static'] = $config['root'] . 'static/';
	
	if (!isset($config['image_sticky']))
		$config['image_sticky'] = $config['dir']['static'] . 'sticky.gif';
	if (!isset($config['image_locked']))
		$config['image_locked'] = $config['dir']['static'] . 'locked.gif';
	if (!isset($config['image_bumplocked']))
		$config['image_bumplocked'] = $config['dir']['static'] . 'sage.gif';
	if (!isset($config['image_deleted']))
		$config['image_deleted'] = $config['dir']['static'] . 'deleted.png';
	if (!isset($config['image_zip']))
		$config['image_zip'] = $config['dir']['static'] . 'zip.png';
	
	if (!isset($config['uri_thumb']))
		$config['uri_thumb'] = $config['root'] . $board['dir'] . $config['dir']['thumb'];
	elseif (isset($board['dir']))
		$config['uri_thumb'] = sprintf($config['uri_thumb'], $board['dir']);
	
	if (!isset($config['uri_img']))
		$config['uri_img'] = $config['root'] . $board['dir'] . $config['dir']['img'];
	elseif (isset($board['dir']))
		$config['uri_img'] = sprintf($config['uri_img'], $board['dir']);
	
	if (!isset($config['uri_stylesheets']))
		$config['uri_stylesheets'] = $config['root'] . 'stylesheets/';
	
	if (!isset($config['url_stylesheet']))
		$config['url_stylesheet'] = $config['uri_stylesheets'] . 'style.css';
	if (!isset($config['url_javascript']))
		$config['url_javascript'] = $config['root'] . $config['file_script'];
	if (!isset($config['additional_javascript_url']))
		$config['additional_javascript_url'] = $config['root'];
	
	if ($config['root_file']) {
		chdir($config['root_file']);
	}

	if ($config['verbose_errors']) {
		error_reporting(E_ALL);
		ini_set('display_errors', 1);
	}
	
	// Keep the original address to properly comply with other board configurations
	if (!isset($__ip))
		$__ip = $_SERVER['REMOTE_ADDR'];
	
	// ::ffff:0.0.0.0
	if (preg_match('/^\:\:(ffff\:)?(\d+\.\d+\.\d+\.\d+)$/', $__ip, $m))
		$_SERVER['REMOTE_ADDR'] = $m[2];
	
	if (_setlocale(LC_ALL, $config['locale']) === false) {
		$error('The specified locale (' . $config['locale'] . ') does not exist on your platform!');
	}
	
	if (extension_loaded('gettext')) {
		bindtextdomain('tinyboard', './inc/locale');
		bind_textdomain_codeset('tinyboard', 'UTF-8');
		textdomain('tinyboard');
	} else {
		_bindtextdomain('tinyboard', './inc/locale');
		_bind_textdomain_codeset('tinyboard', 'UTF-8');
		_textdomain('tinyboard');
	}
	
	
	if ($config['syslog'])
		openlog('tinyboard', LOG_ODELAY, LOG_SYSLOG); // open a connection to sysem logger
	
	if ($config['recaptcha'])
		require_once 'inc/lib/recaptcha/recaptchalib.php';
	if ($config['cache']['enabled'])
		require_once 'inc/cache.php';
	event('load-config');
}

function basic_error_function_because_the_other_isnt_loaded_yet($message, $priority = true) {
	global $config;
	
	if ($config['syslog'] && $priority !== false) {
		// Use LOG_NOTICE instead of LOG_ERR or LOG_WARNING because most error message are not significant.
		_syslog($priority !== true ? $priority : LOG_NOTICE, $message);
	}
	
	// Yes, this is horrible.
	die('<!DOCTYPE html><html><head><title>Error</title>' .
		'<style type="text/css">' .
			'body{text-align:center;font-family:arial, helvetica, sans-serif;font-size:10pt;}' .
			'p{padding:0;margin:20px 0;}' .
			'p.c{font-size:11px;}' .
		'</style></head>' .
		'<body><h2>Error</h2>' . $message . '<hr/>' .
		'<p class="c">This alternative error page is being displayed because the other couldn\'t be found or hasn\'t loaded yet.</p></body></html>');
}

function fatal_error_handler() { 
	if ($error = error_get_last()) {
		if ($error['type'] == E_ERROR) {
			if (function_exists('error')) {
				error('Caught fatal error: ' . $error['message'] . ' in <strong>' . $error['file'] . '</strong> on line ' . $error['line'], LOG_ERR);
			} else {
				basic_error_function_because_the_other_isnt_loaded_yet('Caught fatal error: ' . $error['message'] . ' in ' . $error['file'] . ' on line ' . $error['line'], LOG_ERR);
			}
		}
	}
}

function _syslog($priority, $message) {
	if (isset($_SERVER['REMOTE_ADDR'], $_SERVER['REQUEST_METHOD'], $_SERVER['REQUEST_URI'])) {
		// CGI
		syslog($priority, $message . ' - client: ' . $_SERVER['REMOTE_ADDR'] . ', request: "' . $_SERVER['REQUEST_METHOD'] . ' ' . $_SERVER['REQUEST_URI'] . '"');
	} else {
		syslog($priority, $message);
	}
}

function create_antibot($board, $thread = null) {
	require_once dirname(__FILE__) . '/anti-bot.php';
	
	return _create_antibot($board, $thread);
}

function rebuildThemes($action, $board = false) {
	// List themes
	$query = query("SELECT `theme` FROM `theme_settings` WHERE `name` IS NULL AND `value` IS NULL") or error(db_error());

	while ($theme = $query->fetch()) {
		rebuildTheme($theme['theme'], $action, $board);
	}
}


function loadThemeConfig($_theme) {
	global $config;

	if (!file_exists($config['dir']['themes'] . '/' . $_theme . '/info.php'))
		return false;

	// Load theme information into $theme
	include $config['dir']['themes'] . '/' . $_theme . '/info.php';

	return $theme;
}

function rebuildTheme($theme, $action, $board = false) {
	global $config, $_theme;
	$_theme = $theme;

	$theme = loadThemeConfig($_theme);

	if (file_exists($config['dir']['themes'] . '/' . $_theme . '/theme.php')) {
		require_once $config['dir']['themes'] . '/' . $_theme . '/theme.php';
	
		$theme['build_function']($action, themeSettings($_theme), $board);
	}
}


function themeSettings($theme) {
	$query = prepare("SELECT `name`, `value` FROM `theme_settings` WHERE `theme` = :theme AND `name` IS NOT NULL");
	$query->bindValue(':theme', $theme);
	$query->execute() or error(db_error($query));

	$settings = array();
	while ($s = $query->fetch()) {
		$settings[$s['name']] = $s['value'];
	}

	return $settings;
}

function sprintf3($str, $vars, $delim = '%') {
	$replaces = array();
	foreach ($vars as $k => $v) {
		$replaces[$delim . $k . $delim] = $v;
	}
	return str_replace(array_keys($replaces),
	                   array_values($replaces), $str);
}

function mb_substr_replace($string, $replacement, $start, $length) {
	return mb_substr($string, 0, $start) . $replacement . mb_substr($string, $start + $length);
}

function setupBoard($array) {
	global $board, $config;
	
	$board = array(
		'uri' => $array['uri'],
		'title' => $array['title'],
		'subtitle' => $array['subtitle']
	);
	
	// older versions
	$board['name'] = &$board['title'];
	
	$board['dir'] = sprintf($config['board_path'], $board['uri']);
	$board['url'] = sprintf($config['board_abbreviation'], $board['uri']);
	
	loadConfig();
	
	if (!file_exists($board['dir']))
		@mkdir($board['dir'], 0777) or error("Couldn't create " . $board['dir'] . ". Check permissions.", true);
	if (!file_exists($board['dir'] . $config['dir']['img']))
		@mkdir($board['dir'] . $config['dir']['img'], 0777)
			or error("Couldn't create " . $board['dir'] . $config['dir']['img'] . ". Check permissions.", true);
	if (!file_exists($board['dir'] . $config['dir']['thumb']))
		@mkdir($board['dir'] . $config['dir']['thumb'], 0777)
			or error("Couldn't create " . $board['dir'] . $config['dir']['img'] . ". Check permissions.", true);
	if (!file_exists($board['dir'] . $config['dir']['res']))
		@mkdir($board['dir'] . $config['dir']['res'], 0777)
			or error("Couldn't create " . $board['dir'] . $config['dir']['img'] . ". Check permissions.", true);
}

function openBoard($uri) {
	$board = getBoardInfo($uri);
	if ($board) {
		setupBoard($board);
		return true;
	}
	return false;
}

function getBoardInfo($uri) {
	global $config;

	if ($config['cache']['enabled'] && ($board = cache::get('board_' . $uri))) {
		return $board;
	}
	
	$query = prepare("SELECT * FROM `boards` WHERE `uri` = :uri LIMIT 1");
	$query->bindValue(':uri', $uri);
	$query->execute() or error(db_error($query));
	
	if ($board = $query->fetch()) {
		if ($config['cache']['enabled'])
			cache::set('board_' . $uri, $board);
		return $board;
	}

	return false;
}

function boardTitle($uri) {
	$board = getBoardInfo($uri);
	if ($board)
		return $board['title'];
	return false;
}

function purge($uri) {
	global $config, $debug;
	
	// Fix for Unicode
	$uri = urlencode($uri); 
	$uri = str_replace("%2F", "/", $uri);
	$uri = str_replace("%3A", ":", $uri);
	
	if (preg_match($config['referer_match'], $config['root']) && isset($_SERVER['REQUEST_URI'])) {
		$uri = (str_replace('\\', '/', dirname($_SERVER['REQUEST_URI'])) == '/' ? '/' : str_replace('\\', '/', dirname($_SERVER['REQUEST_URI'])) . '/') . $uri;
	} else {
		$uri = $config['root'] . $uri;
	}
	
	if ($config['debug']) {
		$debug['purge'][] = $uri;
	}
			
	foreach ($config['purge'] as &$purge) {
		$host = &$purge[0];
		$port = &$purge[1];
		$http_host = isset($purge[2]) ? $purge[2] : (isset($_SERVER['HTTP_HOST']) ? $_SERVER['HTTP_HOST'] : 'localhost');
		$request = "PURGE {$uri} HTTP/1.1\r\nHost: {$http_host}\r\nUser-Agent: Tinyboard\r\nConnection: Close\r\n\r\n";
		if ($fp = fsockopen($host, $port, $errno, $errstr, $config['purge_timeout'])) {
			fwrite($fp, $request);
			fclose($fp);
		} else {
			// Cannot connect?
			error('Could not PURGE for ' . $host);
		}
	}
}

function file_write($path, $data, $simple = false, $skip_purge = false) {
	global $config, $debug;
	
	if (preg_match('/^remote:\/\/(.+)\:(.+)$/', $path, $m)) {
		if (isset($config['remote'][$m[1]])) {
			require_once 'inc/remote.php';
			
			$remote = new Remote($config['remote'][$m[1]]);
			$remote->write($data, $m[2]);
			return;
		} else {
			error('Invalid remote server: ' . $m[1]);
		}
	}
	
	if (!$fp = fopen($path, $simple ? 'w' : 'c'))
		error('Unable to open file for writing: ' . $path);
	
	// File locking
	if (!$simple && !flock($fp, LOCK_EX)) {
		error('Unable to lock file: ' . $path);
	}
	
	// Truncate file
	if (!$simple && !ftruncate($fp, 0))
		error('Unable to truncate file: ' . $path);
		
	// Write data
	if (($bytes = fwrite($fp, $data)) === false)
		error('Unable to write to file: ' . $path);
	
	// Unlock
	if (!$simple)
		flock($fp, LOCK_UN);
	
	// Close
	if (!fclose($fp))
		error('Unable to close file: ' . $path);
	
	if (!$skip_purge && isset($config['purge'])) {
		// Purge cache
		if (basename($path) == $config['file_index']) {
			// Index file (/index.html); purge "/" as well
			$uri = dirname($path);
			// root
			if ($uri == '.')
				$uri = '';
			else
				$uri .= '/';
			purge($uri);
		}
		purge($path);
	}
	
	if ($config['debug']) {
		$debug['write'][] = $path . ': ' . $bytes . ' bytes';
	}
	
	event('write', $path);
}

function file_unlink($path) {
	global $config, $debug;
	
	if ($config['debug']) {
		if (!isset($debug['unlink']))
			$debug['unlink'] = array();
		$debug['unlink'][] = $path;
	}
	
	$ret = @unlink($path);
	if (isset($config['purge']) && $path[0] != '/' && isset($_SERVER['HTTP_HOST'])) {
		// Purge cache
		if (basename($path) == $config['file_index']) {
			// Index file (/index.html); purge "/" as well
			$uri = dirname($path);
			// root
			if ($uri == '.')
				$uri = '';
			else
				$uri .= '/';
			purge($uri);
		}
		purge($path);
	}
	
	event('unlink', $path);
	
	return $ret;
}

function hasPermission($action = null, $board = null, $_mod = null) {
	global $config;
		
	if (isset($_mod))
		$mod = &$_mod;
	else
		global $mod;
	
	if (!is_array($mod))
		return false;
	
	if (isset($action) && $mod['type'] < $action)
		return false;
	
	if (!isset($board) || $config['mod']['skip_per_board'])
		return true;
	
	if (!isset($mod['boards']))
		return false;
	
	if (!in_array('*', $mod['boards']) && !in_array($board, $mod['boards']))
		return false;
	
	return true;
}

function listBoards() {
	global $config;
	
	if ($config['cache']['enabled'] && ($boards = cache::get('all_boards')))
		return $boards;
	
	$query = query("SELECT * FROM `boards` ORDER BY `uri`") or error(db_error());
	$boards = $query->fetchAll();
	
	if ($config['cache']['enabled'])
		cache::set('all_boards', $boards);
	
	return $boards;
}

function checkFlood($post) {
	global $board, $config;
	
	$query = prepare(sprintf("SELECT * FROM `posts_%s` WHERE (`ip` = :ip AND `time` >= :floodtime) OR (`ip` = :ip AND `body` != '' AND `body` = :body AND `time` >= :floodsameiptime) OR (`body` != ''  AND `body` = :body AND `time` >= :floodsametime) LIMIT 1", $board['uri']));
	$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
	$query->bindValue(':body', $post['body']);
	$query->bindValue(':floodtime', time()-$config['flood_time'], PDO::PARAM_INT);
	$query->bindValue(':floodsameiptime', time()-$config['flood_time_ip'], PDO::PARAM_INT);
	$query->bindValue(':floodsametime', time()-$config['flood_time_same'], PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	$flood = (bool)$query->fetch();
	
	if (event('check-flood', $post))
		return true;
	
	return $flood;
}

function until($timestamp) {
	$difference = $timestamp - time();
	if ($difference < 60) {
		return $difference . ' ' . ngettext('second', 'seconds', $difference);
	} elseif ($difference < 60*60) {
		return ($num = round($difference/(60))) . ' ' . ngettext('minute', 'minutes', $num);
	} elseif ($difference < 60*60*24) {
		return ($num = round($difference/(60*60))) . ' ' . ngettext('hour', 'hours', $num);
	} elseif ($difference < 60*60*24*7) {
		return ($num = round($difference/(60*60*24))) . ' ' . ngettext('day', 'days', $num);
	} elseif ($difference < 60*60*24*365) {
		return ($num = round($difference/(60*60*24*7))) . ' ' . ngettext('week', 'weeks', $num);
	}

	return ($num = round($difference/(60*60*24*365))) . ' ' . ngettext('year', 'years', $num);
}

function ago($timestamp) {
	$difference = time() - $timestamp;
	if ($difference < 60) {
		return $difference . ' ' . ngettext('second', 'seconds', $difference);
	} elseif ($difference < 60*60) {
		return ($num = round($difference/(60))) . ' ' . ngettext('minute', 'minutes', $num);
	} elseif ($difference < 60*60*24) {
		return ($num = round($difference/(60*60))) . ' ' . ngettext('hour', 'hours', $num);
	} elseif ($difference < 60*60*24*7) {
		return ($num = round($difference/(60*60*24))) . ' ' . ngettext('day', 'days', $num);
	} elseif ($difference < 60*60*24*365) {
		return ($num = round($difference/(60*60*24*7))) . ' ' . ngettext('week', 'weeks', $num);
	}

	return ($num = round($difference/(60*60*24*365))) . ' ' . ngettext('year', 'years', $num);
}

function displayBan($ban) {
	global $config;
	
	if (!$ban['seen']) {
		$query = prepare("UPDATE `bans` SET `seen` = 1 WHERE `id` = :id");
		$query->bindValue(':id', $ban['id'], PDO::PARAM_INT);
		$query->execute() or error(db_error($query));
	}
	
	$ban['ip'] = $_SERVER['REMOTE_ADDR'];
	
	// Show banned page and exit
	die(
		Element('page.html', array(
			'title' => _('Banned!'),
			'config' => $config,
			'body' => Element('banned.html', array(
				'config' => $config,
				'ban' => $ban
			)
		))
	));
}

function checkBan($board = 0) {
	global $config;
	
	if (!isset($_SERVER['REMOTE_ADDR'])) {
		// Server misconfiguration
		return;
	}		
	
	if (event('check-ban', $board))
		return true;
	
	$query = prepare("SELECT `set`, `expires`, `reason`, `board`, `seen`, `bans`.`id` FROM `bans` WHERE (`board` IS NULL OR `board` = :board) AND `ip` = :ip ORDER BY `expires` IS NULL DESC, `expires` DESC, `expires` DESC LIMIT 1");
	$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
	$query->bindValue(':board', $board);
	$query->execute() or error(db_error($query));
	if ($query->rowCount() < 1 && $config['ban_range']) {
		$query = prepare("SELECT `set`, `expires`, `reason`, `board`, `seen`, `bans`.`id` FROM `bans` WHERE (`board` IS NULL OR `board` = :board) AND :ip LIKE REPLACE(REPLACE(`ip`, '%', '!%'), '*', '%') ESCAPE '!' ORDER BY `expires` IS NULL DESC, `expires` DESC LIMIT 1");
		$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
		$query->bindValue(':board', $board);
		$query->execute() or error(db_error($query));
	}
	
	if ($query->rowCount() < 1 && $config['ban_cidr'] && !isIPv6()) {
		// my most insane SQL query yet
		$query = prepare("SELECT `set`, `expires`, `reason`, `board`, `seen`, `bans`.`id` FROM `bans` WHERE (`board` IS NULL OR `board` = :board)
			AND (					
				`ip` REGEXP '^(\[0-9]+\.\[0-9]+\.\[0-9]+\.\[0-9]+\)\/(\[0-9]+)$'
					AND
				:ip >= INET_ATON(SUBSTRING_INDEX(`ip`, '/', 1))
					AND
				:ip < INET_ATON(SUBSTRING_INDEX(`ip`, '/', 1)) + POW(2, 32 - SUBSTRING_INDEX(`ip`, '/', -1))
			)
			ORDER BY `expires` IS NULL DESC, `expires` DESC LIMIT 1");
		$query->bindValue(':ip', ip2long($_SERVER['REMOTE_ADDR']));
		$query->bindValue(':board', $board);
		$query->execute() or error(db_error($query));
	}
	
	if ($ban = $query->fetch()) {
		if ($ban['expires'] && $ban['expires'] < time()) {
			// Ban expired
			$query = prepare("DELETE FROM `bans` WHERE `id` = :id");
			$query->bindValue(':id', $ban['id'], PDO::PARAM_INT);
			$query->execute() or error(db_error($query));
			
			if ($config['require_ban_view'] && !$ban['seen']) {
				displayBan($ban);
			}
			
			return;
		}
		
		displayBan($ban);
	}
	
	// I'm not sure where else to put this. It doesn't really matter where; it just needs to be called every now and then to keep the ban list tidy.
	purge_bans();
}

// No reason to keep expired bans in the database (except those that haven't been viewed yet)
function purge_bans() {
	$query = prepare("DELETE FROM `bans` WHERE `expires` IS NOT NULL AND `expires` < :time AND `seen` = 1");
	$query->bindValue(':time', time());
	$query->execute() or error(db_error($query));
}

function threadLocked($id) {
	global $board;
	
	if (event('check-locked', $id))
		return true;
	
	$query = prepare(sprintf("SELECT `locked` FROM `posts_%s` WHERE `id` = :id AND `thread` IS NULL LIMIT 1", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error());
	
	if (!$post = $query->fetch()) {
		// Non-existant, so it can't be locked...
		return false;
	}
	
	return (bool)$post['locked'];
}

function threadSageLocked($id) {
	global $board;
	
	if (event('check-sage-locked', $id))
		return true;
	
	$query = prepare(sprintf("SELECT `sage` FROM `posts_%s` WHERE `id` = :id AND `thread` IS NULL LIMIT 1", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error());
	
	if (!$post = $query->fetch()) {
		// Non-existant, so it can't be locked...
		return false;
	}
	
	return (bool) $post['sage'];
}

function threadExists($id) {
	global $board;
	
	$query = prepare(sprintf("SELECT 1 FROM `posts_%s` WHERE `id` = :id AND `thread` IS NULL LIMIT 1", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error());
	
	if ($query->rowCount()) {
		return true;
	}

	return false;
}

function post(array $post) {
	global $pdo, $board;
	$query = prepare(sprintf("INSERT INTO `posts_%s` (`id`, `thread`, `subject`, `email`, `name`, `trip`, `capcode`, `body`, `body_nomarkup`, `time`, `bump`, `thumb`, `thumbwidth`, `thumbheight`, `file`, `filewidth`, `fileheight`, `filesize`, `filename`, `filehash`, `password`, `ip`, `sticky`, `locked`, `sage`, `embed`) VALUES ( NULL, :thread, :subject, :email, :name, :trip, :capcode, :body, :body_nomarkup, :time, :time, :thumb, :thumbwidth, :thumbheight, :file, :width, :height, :filesize, :filename, :filehash, :password, :ip, :sticky, :locked, 0, :embed)", $board['uri']));
	
	// Basic stuff
	if (!empty($post['subject'])) {
		$query->bindValue(':subject', $post['subject']);
	} else {
		$query->bindValue(':subject', NULL, PDO::PARAM_NULL);
	}
	
	if (!empty($post['email'])) {
		$query->bindValue(':email', $post['email']);
	} else {
		$query->bindValue(':email', NULL, PDO::PARAM_NULL);
	}
	
	if (!empty($post['trip'])) {
		$query->bindValue(':trip', $post['trip']);
	} else {
		$query->bindValue(':trip', NULL, PDO::PARAM_NULL);
	}
	
	$query->bindValue(':name', $post['name']);
	$query->bindValue(':body', $post['body']);
	$query->bindValue(':body_nomarkup', $post['body_nomarkup']);
	$query->bindValue(':time', isset($post['time']) ? $post['time'] : time(), PDO::PARAM_INT);
	$query->bindValue(':password', $post['password']);		
	$query->bindValue(':ip', isset($post['ip']) ? $post['ip'] : $_SERVER['REMOTE_ADDR']);
	
	if ($post['op'] && $post['mod'] && isset($post['sticky']) && $post['sticky']) {
		$query->bindValue(':sticky', 1, PDO::PARAM_INT);
	} else {
		$query->bindValue(':sticky', 0, PDO::PARAM_INT);
	}
	
	if ($post['op'] && $post['mod'] && isset($post['locked']) && $post['locked']) {
		$query->bindValue(':locked', 1, PDO::PARAM_INT);
	} else {
		$query->bindValue(':locked', 0, PDO::PARAM_INT);
	}
	
	if ($post['mod'] && isset($post['capcode']) && $post['capcode']) {
		$query->bindValue(':capcode', $post['capcode'], PDO::PARAM_INT);
	} else {
		$query->bindValue(':capcode', NULL, PDO::PARAM_NULL);
	}
	
	if (!empty($post['embed'])) {
		$query->bindValue(':embed', $post['embed']);
	} else {
		$query->bindValue(':embed', NULL, PDO::PARAM_NULL);
	}
	
	if ($post['op']) {
		// No parent thread, image
		$query->bindValue(':thread', null, PDO::PARAM_NULL);
	} else {
		$query->bindValue(':thread', $post['thread'], PDO::PARAM_INT);
	}
	
	if ($post['has_file']) {
		$query->bindValue(':thumb', $post['thumb']);
		$query->bindValue(':thumbwidth', $post['thumbwidth'], PDO::PARAM_INT);
		$query->bindValue(':thumbheight', $post['thumbheight'], PDO::PARAM_INT);
		$query->bindValue(':file', $post['file']);
		
		if (isset($post['width'], $post['height'])) {
			$query->bindValue(':width', $post['width'], PDO::PARAM_INT);
			$query->bindValue(':height', $post['height'], PDO::PARAM_INT);
		} else {
			$query->bindValue(':width', null, PDO::PARAM_NULL);
			$query->bindValue(':height', null, PDO::PARAM_NULL);
		}
		
		$query->bindValue(':filesize', $post['filesize'], PDO::PARAM_INT);
		$query->bindValue(':filename', $post['filename']);
		$query->bindValue(':filehash', $post['filehash']);
	} else {
		$query->bindValue(':thumb', null, PDO::PARAM_NULL);
		$query->bindValue(':thumbwidth', null, PDO::PARAM_NULL);
		$query->bindValue(':thumbheight', null, PDO::PARAM_NULL);
		$query->bindValue(':file', null, PDO::PARAM_NULL);
		$query->bindValue(':width', null, PDO::PARAM_NULL);
		$query->bindValue(':height', null, PDO::PARAM_NULL);
		$query->bindValue(':filesize', null, PDO::PARAM_NULL);
		$query->bindValue(':filename', null, PDO::PARAM_NULL);
		$query->bindValue(':filehash', null, PDO::PARAM_NULL);
	}
	
	if (!$query->execute()) {
		undoImage($post);
		error(db_error($query));
	}
	
	return $pdo->lastInsertId();
}

function bumpThread($id) {
	global $board;
	
	if (event('bump', $id))
		return true;
	
	$query = prepare(sprintf("UPDATE `posts_%s` SET `bump` = :time WHERE `id` = :id AND `thread` IS NULL", $board['uri']));
	$query->bindValue(':time', time(), PDO::PARAM_INT);
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
}

// Remove file from post
function deleteFile($id, $remove_entirely_if_already=true) {
	global $board, $config;
	
	$query = prepare(sprintf("SELECT `thread`,`thumb`,`file` FROM `posts_%s` WHERE `id` = :id LIMIT 1", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	if (!$post = $query->fetch())
		error($config['error']['invalidpost']);
	
	if ($post['file'] == 'deleted' && !$post['thread'])
		return; // Can't delete OP's image completely.
	
	$query = prepare(sprintf("UPDATE `posts_%s` SET `thumb` = NULL, `thumbwidth` = NULL, `thumbheight` = NULL, `filewidth` = NULL, `fileheight` = NULL, `filesize` = NULL, `filename` = NULL, `filehash` = NULL, `file` = :file WHERE `id` = :id", $board['uri']));
	if ($post['file'] == 'deleted' && $remove_entirely_if_already) {
		// Already deleted; remove file fully
		$query->bindValue(':file', null, PDO::PARAM_NULL);
	} else {
		// Delete thumbnail
		file_unlink($board['dir'] . $config['dir']['thumb'] . $post['thumb']);
		
		// Delete file
		file_unlink($board['dir'] . $config['dir']['img'] . $post['file']);
		
		// Set file to 'deleted'
		$query->bindValue(':file', 'deleted', PDO::PARAM_INT);
	}
	
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	if ($post['thread'])
		buildThread($post['thread']);
	else
		buildThread($id);
}

// rebuild post (markup)
function rebuildPost($id) {
	global $board;
	
	$query = prepare(sprintf("SELECT `body_nomarkup`, `thread` FROM `posts_%s` WHERE `id` = :id", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	if ((!$post = $query->fetch()) || !$post['body_nomarkup'])
		return false;
	
	markup($body = &$post['body_nomarkup']);
	
	$query = prepare(sprintf("UPDATE `posts_%s` SET `body` = :body WHERE `id` = :id", $board['uri']));
	$query->bindValue(':body', $body);
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	buildThread($post['thread'] ? $post['thread'] : $id);
	
	return true;
}

// Delete a post (reply or thread)
function deletePost($id, $error_if_doesnt_exist=true, $rebuild_after=true) {
	global $board, $config;
	
	// Select post and replies (if thread) in one query
	$query = prepare(sprintf("SELECT `id`,`thread`,`thumb`,`file` FROM `posts_%s` WHERE `id` = :id OR `thread` = :id", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	if ($query->rowCount() < 1) {
		if ($error_if_doesnt_exist)
			error($config['error']['invalidpost']);
		else return false;
	}
	
	$ids = array();
	
	// Delete posts and maybe replies
	while ($post = $query->fetch()) {
		if (!$post['thread']) {
			// Delete thread HTML page
			file_unlink($board['dir'] . $config['dir']['res'] . sprintf($config['file_page'], $post['id']));
			
			$antispam_query = prepare('DELETE FROM `antispam` WHERE `board` = :board AND `thread` = :thread');
			$antispam_query->bindValue(':board', $board['uri']);
			$antispam_query->bindValue(':thread', $post['id']);
			$antispam_query->execute() or error(db_error($antispam_query));
		} elseif ($query->rowCount() == 1) {
			// Rebuild thread
			$rebuild = &$post['thread'];
		}
		if ($post['thumb']) {
			// Delete thumbnail
			file_unlink($board['dir'] . $config['dir']['thumb'] . $post['thumb']);
		}
		if ($post['file']) {
			// Delete file
			file_unlink($board['dir'] . $config['dir']['img'] . $post['file']);
		}
		
		$ids[] = (int)$post['id'];
		
	}
	
	$query = prepare(sprintf("DELETE FROM `posts_%s` WHERE `id` = :id OR `thread` = :id", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	$query = prepare("SELECT `board`, `post` FROM `cites` WHERE `target_board` = :board AND (`target` = " . implode(' OR `target` = ', $ids) . ")");
	$query->bindValue(':board', $board['uri']);
	$query->execute() or error(db_error($query));
	while ($cite = $query->fetch()) {
		if ($board['uri'] != $cite['board']) {
			if (!isset($tmp_board))
				$tmp_board = $board['uri'];
			openBoard($cite['board']);
		}
		rebuildPost($cite['post']);
	}
	
	if (isset($tmp_board))
		openBoard($tmp_board);
	
	$query = prepare("DELETE FROM `cites` WHERE (`target_board` = :board AND `target` = :id) OR (`board` = :board AND `post` = :id)");
	$query->bindValue(':board', $board['uri']);
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));

	if (isset($rebuild) && $rebuild_after) {
		buildThread($rebuild);
	}
	
	return true;
}

function clean() {
	global $board, $config;
	$offset = round($config['max_pages']*$config['threads_per_page']);
	
	// I too wish there was an easier way of doing this...
	$query = prepare(sprintf("SELECT `id` FROM `posts_%s` WHERE `thread` IS NULL ORDER BY `sticky` DESC, `bump` DESC LIMIT :offset, 9001", $board['uri']));
	$query->bindValue(':offset', $offset, PDO::PARAM_INT);
	
	$query->execute() or error(db_error($query));
	while ($post = $query->fetch()) {
		deletePost($post['id']);
	}
}

function index($page, $mod=false) {
	global $board, $config, $debug;

	$body = '';
	$offset = round($page*$config['threads_per_page']-$config['threads_per_page']);
	
	$query = prepare(sprintf("SELECT * FROM `posts_%s` WHERE `thread` IS NULL ORDER BY `sticky` DESC, `bump` DESC LIMIT :offset,:threads_per_page", $board['uri']));
	$query->bindValue(':offset', $offset, PDO::PARAM_INT);
	$query->bindValue(':threads_per_page', $config['threads_per_page'], PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	if ($query->rowcount() < 1 && $page > 1)
		return false;
	while ($th = $query->fetch()) {
		$thread = new Thread(
			$th['id'], $th['subject'], $th['email'], $th['name'], $th['trip'], $th['capcode'], $th['body'], $th['time'], $th['thumb'],
			$th['thumbwidth'], $th['thumbheight'], $th['file'], $th['filewidth'], $th['fileheight'], $th['filesize'], $th['filename'], $th['ip'],
			$th['sticky'], $th['locked'], $th['sage'], $th['embed'], $mod ? '?/' : $config['root'], $mod
		);
		
		if ($config['cache']['enabled'] && $cached = cache::get("thread_index_{$board['uri']}_{$th['id']}")) {
			$replies = $cached['replies'];
			$omitted = $cached['omitted'];
		} else {
			$posts = prepare(sprintf("SELECT * FROM `posts_%s` WHERE `thread` = :id ORDER BY `id` DESC LIMIT :limit", $board['uri']));
			$posts->bindValue(':id', $th['id']);
			$posts->bindValue(':limit', ($th['sticky'] ? $config['threads_preview_sticky'] : $config['threads_preview']), PDO::PARAM_INT);
			$posts->execute() or error(db_error($posts));
			
			$replies = array_reverse($posts->fetchAll(PDO::FETCH_ASSOC));
			
			if (count($replies) == ($th['sticky'] ? $config['threads_preview_sticky'] : $config['threads_preview'])) {
				$count = numPosts($th['id']);
				$omitted = array('post_count' => $count['replies'], 'image_count' => $count['images']);
			} else {
				$omitted = false;
			}
			
			if ($config['cache']['enabled'])
				cache::set("thread_index_{$board['uri']}_{$th['id']}", array(
					'replies' => $replies,
					'omitted' => $omitted,
				));
		}
		
		$num_images = 0;
		foreach ($replies as $po) {
			if ($po['file'])
				$num_images++;
		
			$thread->add(new Post(
				$po['id'], $th['id'], $po['subject'], $po['email'], $po['name'], $po['trip'], $po['capcode'], $po['body'], $po['time'],
				$po['thumb'], $po['thumbwidth'], $po['thumbheight'], $po['file'], $po['filewidth'], $po['fileheight'], $po['filesize'],
				$po['filename'], $po['ip'], $po['embed'], $mod ? '?/' : $config['root'], $mod)
			);
		}
		
		if ($omitted) {
			$thread->omitted = $omitted['post_count'] - ($th['sticky'] ? $config['threads_preview_sticky'] : $config['threads_preview']);
			$thread->omitted_images = $omitted['image_count'] - $num_images;
		}
		
		$body .= $thread->build(true);
	}
	
	return array(
		'board' => $board,
		'body' => $body,
		'post_url' => $config['post_url'],
		'config' => $config,
		'boardlist' => createBoardlist($mod)
	);
}

function getPageButtons($pages, $mod=false) {
	global $config, $board;
	
	$btn = array();
	$root = ($mod ? '?/' : $config['root']) . $board['dir'];
	
	foreach ($pages as $num => $page) {
		if (isset($page['selected'])) {
			// Previous button
			if ($num == 0) {
				// There is no previous page.
				$btn['prev'] = _('Previous');
			} else {
				$loc = ($mod ? '?/' . $board['uri'] . '/' : '') .
					($num == 1 ?
						$config['file_index']
					:
						sprintf($config['file_page'], $num)
					);
				
				$btn['prev'] = '<form action="' . ($mod ? '' : $root . $loc) . '" method="get">' .
					($mod ?
						'<input type="hidden" name="status" value="301" />' .
						'<input type="hidden" name="r" value="' . htmlentities($loc) . '" />'
					:'') .
				'<input type="submit" value="' . _('Previous') . '" /></form>';
			}
			
			if ($num == count($pages) - 1) {
				// There is no next page.
				$btn['next'] = _('Next');
			} else {
				$loc = ($mod ? '?/' . $board['uri'] . '/' : '') . sprintf($config['file_page'], $num + 2);
				
				$btn['next'] = '<form action="' . ($mod ? '' : $root . $loc) . '" method="get">' .
					($mod ?
						'<input type="hidden" name="status" value="301" />' .
						'<input type="hidden" name="r" value="' . htmlentities($loc) . '" />'
					:'') .
				'<input type="submit" value="' . _('Next') . '" /></form>';
			}
		}
	}
	
	return $btn;
}

function getPages($mod=false) {
	global $board, $config;
	
	// Count threads
	$query = query(sprintf("SELECT COUNT(`id`) as `num` FROM `posts_%s` WHERE `thread` IS NULL", $board['uri'])) or error(db_error());
	
	$count = current($query->fetch());
	$count = floor(($config['threads_per_page'] + $count - 1) / $config['threads_per_page']);
	
	if ($count < 1) $count = 1;
	
	$pages = array();
	for ($x=0;$x<$count && $x<$config['max_pages'];$x++) {
		$pages[] = array(
			'num' => $x+1,
			'link' => $x==0 ? ($mod ? '?/' : $config['root']) . $board['dir'] . $config['file_index'] : ($mod ? '?/' : $config['root']) . $board['dir'] . sprintf($config['file_page'], $x+1)
		);
	}
	
	return $pages;
}

function makerobot($body) {
	global $config;
	$body = strtolower($body);
	
	// Leave only letters
	$body = preg_replace('/[^a-z]/i', '', $body);
	// Remove repeating characters
	if ($config['robot_strip_repeating'])
		$body = preg_replace('/(.)\\1+/', '$1', $body);
	
	return sha1($body);
}

function checkRobot($body) {
	if (empty($body) || event('check-robot', $body))
		return true;
	
	$body = makerobot($body);
	$query = prepare("SELECT 1 FROM `robot` WHERE `hash` = :hash LIMIT 1");
	$query->bindValue(':hash', $body);
	$query->execute() or error(db_error($query));
	
	if ($query->fetch()) {
		return true;
	}

	// Insert new hash
	$query = prepare("INSERT INTO `robot` VALUES (:hash)");
	$query->bindValue(':hash', $body);
	$query->execute() or error(db_error($query));
	return false;
}

// Returns an associative array with 'replies' and 'images' keys
function numPosts($id) {
	global $board;
	$query = prepare(sprintf("SELECT COUNT(*) as `num` FROM `posts_%s` WHERE `thread` = :thread UNION ALL SELECT COUNT(*) FROM `posts_%s` WHERE `file` IS NOT NULL AND `thread` = :thread", $board['uri'], $board['uri']));
	$query->bindValue(':thread', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	$num_posts = $query->fetch();
	$num_posts = $num_posts['num'];
	$num_images = $query->fetch();
	$num_images = $num_images['num'];
	
	return array('replies' => $num_posts, 'images' => $num_images);
}

function muteTime() {
	global $config;
	
	if ($time = event('mute-time'))
		return $time;
	
	// Find number of mutes in the past X hours
	$query = prepare("SELECT COUNT(*) as `count` FROM `mutes` WHERE `time` >= :time AND `ip` = :ip");
	$query->bindValue(':time', time()-($config['robot_mute_hour']*3600), PDO::PARAM_INT);
	$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
	$query->execute() or error(db_error($query));
	
	$result = $query->fetch();
	if ($result['count'] == 0) return 0;
	return pow($config['robot_mute_multiplier'], $result['count']);
}

function mute() {
	// Insert mute
	$query = prepare("INSERT INTO `mutes` VALUES (:ip, :time)");
	$query->bindValue(':time', time(), PDO::PARAM_INT);
	$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
	$query->execute() or error(db_error($query));
	
	return muteTime();
}

function checkMute() {
	global $config, $debug;
	
	if ($config['cache']['enabled']) {
		// Cached mute?
		if (($mute = cache::get("mute_${_SERVER['REMOTE_ADDR']}")) && ($mutetime = cache::get("mutetime_${_SERVER['REMOTE_ADDR']}"))) {
			error(sprintf($config['error']['youaremuted'], $mute['time'] + $mutetime - time()));
		}
	}
	
	$mutetime = muteTime();
	if ($mutetime > 0) {
		// Find last mute time
		$query = prepare("SELECT `time` FROM `mutes` WHERE `ip` = :ip ORDER BY `time` DESC LIMIT 1");
		$query->bindValue(':ip', $_SERVER['REMOTE_ADDR']);
		$query->execute() or error(db_error($query));
		
		if (!$mute = $query->fetch()) {
			// What!? He's muted but he's not muted...
			return;
		}
		
		if ($mute['time'] + $mutetime > time()) {
			if ($config['cache']['enabled']) {
				cache::set("mute_${_SERVER['REMOTE_ADDR']}", $mute, $mute['time'] + $mutetime - time());
				cache::set("mutetime_${_SERVER['REMOTE_ADDR']}", $mutetime, $mute['time'] + $mutetime - time());
			}
			// Not expired yet
			error(sprintf($config['error']['youaremuted'], $mute['time'] + $mutetime - time()));
		} else {
			// Already expired	
			return;
		}
	}
}

function buildIndex() {
	global $board, $config;
	
	$pages = getPages();
	$antibot = create_antibot($board['uri']);

	$page = 1;
	while ($page <= $config['max_pages'] && $content = index($page)) {
		$filename = $board['dir'] . ($page == 1 ? $config['file_index'] : sprintf($config['file_page'], $page));
		
		$antibot->reset();
		
		$content['pages'] = $pages;
		$content['pages'][$page-1]['selected'] = true;
		$content['btn'] = getPageButtons($content['pages']);
		$content['antibot'] = $antibot;

		file_write($filename, Element('index.html', $content));
		
		$page++;
	}
	if ($page < $config['max_pages']) {
		for (;$page<=$config['max_pages'];$page++) {
			$filename = $board['dir'] . ($page==1 ? $config['file_index'] : sprintf($config['file_page'], $page));
			file_unlink($filename);
		}
	}
}

function buildJavascript() {
	global $config;
	
	$stylesheets = array();
	foreach ($config['stylesheets'] as $name => $uri) {
		$stylesheets[] = array(
			'name' => addslashes($name),
			'uri' => addslashes((!empty($uri) ? $config['uri_stylesheets'] : '') . $uri));
	}
	
	$script = Element('main.js', array(
		'config' => $config,
		'stylesheets' => $stylesheets
	));
	
	// Check if we have translation for the javascripts; if yes, we add it to additional javascripts
	list($pure_locale) = explode(".", $config['locale']);
	if (file_exists ($jsloc = "inc/locale/$pure_locale/LC_MESSAGES/javascript.js")) {
		$script = file_get_contents($jsloc) . "\n\n" . $script;
	}
	
	if ($config['additional_javascript_compile']) {
		foreach ($config['additional_javascript'] as $file) {
			$script .= file_get_contents($file);
		}
	}
	
	if ($config['minify_js']) {
		require_once 'inc/lib/minify/JSMin.php';		
		$script = JSMin::minify($script);
	}
	
	file_write($config['file_script'], $script);
}

function checkDNSBL() {
	global $config;
	
	
	if (isIPv6())
		return; // No IPv6 support yet.
	
	if (!isset($_SERVER['REMOTE_ADDR']))
		return; // Fix your web server configuration
	
	if (in_array($_SERVER['REMOTE_ADDR'], $config['dnsbl_exceptions']))
		return;
	
	$ipaddr = ReverseIPOctets($_SERVER['REMOTE_ADDR']);
	
	foreach ($config['dnsbl'] as $blacklist) {
		if (!is_array($blacklist))
			$blacklist = array($blacklist);
		
		if (($lookup = str_replace('%', $ipaddr, $blacklist[0])) == $blacklist[0])
			$lookup = $ipaddr . '.' . $blacklist[0];
		
		if (!$ip = DNS($lookup))
			continue; // not in list
		
		$blacklist_name = isset($blacklist[2]) ? $blacklist[2] : $blacklist[0];
		
		if (!isset($blacklist[1])) {
			// If you're listed at all, you're blocked.
			error(sprintf($config['error']['dnsbl'], $blacklist_name));
		} elseif (is_array($blacklist[1])) {
			foreach ($blacklist[1] as $octet) {
				if ($ip == $octet || $ip == '127.0.0.' . $octet)
					error(sprintf($config['error']['dnsbl'], $blacklist_name));
			}
		} elseif (is_callable($blacklist[1])) {
			if ($blacklist[1]($ip))
				error(sprintf($config['error']['dnsbl'], $blacklist_name));
		} else {
			if ($ip == $blacklist[1] || $ip == '127.0.0.' . $blacklist[1])
				error(sprintf($config['error']['dnsbl'], $blacklist_name));
		}
	}
}

function isIPv6() {
	return strstr($_SERVER['REMOTE_ADDR'], ':') !== false;
}

function ReverseIPOctets($ip) {
	return implode('.', array_reverse(explode('.', $ip)));
}

function wordfilters(&$body) {
	global $config;
	
	foreach ($config['wordfilters'] as $filter) {
		if (isset($filter[2]) && $filter[2]) {
			$body = preg_replace($filter[0], $filter[1], $body);
		} else {
			$body = str_ireplace($filter[0], $filter[1], $body);
		}
	}
}

function quote($body, $quote=true) {
	global $config;
	
	$body = str_replace('<br/>', "\n", $body);
	
	$body = strip_tags($body);
	
	$body = preg_replace("/(^|\n)/", '$1&gt;', $body);
	
	$body .= "\n";
	
	if ($config['minify_html'])
		$body = str_replace("\n", '&#010;', $body);
	
	return $body;
}

function markup_url($matches) {
	global $config, $markup_urls;
	
	$url = $matches[1];
	$after = $matches[2];
	
	$markup_urls[] = $url;
	
	return '<a target="_blank" rel="nofollow" href="'. $config['link_prefix'] . $url . '">' . $url . '</a>' . $after;
}

function unicodify($body) {
	$body = str_replace('...', '&hellip;', $body);
	$body = str_replace('&lt;--', '&larr;', $body);
	$body = str_replace('--&gt;', '&rarr;', $body);
	
	// En and em- dashes are rendered exactly the same in
	// most monospace fonts (they look the same in code
	// editors).
	$body = str_replace('---', '&mdash;', $body); // em dash
	$body = str_replace('--', '&ndash;', $body); // en dash
	
	return $body;
}

function markup(&$body, $track_cites = false) {
	global $board, $config, $markup_urls;
	
	$body = str_replace("\r", '', $body);
	$body = utf8tohtml($body);
	
	if (mysql_version() < 50503)
		$body = mb_encode_numericentity($body, array(0x010000, 0xffffff, 0, 0xffffff), 'UTF-8');
	
	foreach ($config['markup'] as $markup) {
		if (is_string($markup[1])) {
			$body = preg_replace($markup[0], $markup[1], $body);
		} elseif (is_callable($markup[1])) {
			$body = preg_replace_callback($markup[0], $markup[1], $body);
		}
	}
	
	if ($config['markup_urls']) {
		$markup_urls = array();
		
		$body = preg_replace_callback(
				'/((?:https?:\/\/|ftp:\/\/|irc:\/\/)[^\s<>()"]+?(?:\([^\s<>()"]*?\)[^\s<>()"]*?)*)((?:\s|<|>|"|\.||\]|!|\?|,|&#44;|&quot;)*(?:[\s<>()"]|$))/',
				'markup_url',
				$body,
				-1,
				$num_links);
		
		if ($num_links > $config['max_links'])
			error($config['error']['toomanylinks']);
	}
	
	if ($config['auto_unicode']) {
		$body = unicodify($body);
	
		if ($config['markup_urls']) {
			foreach ($markup_urls as &$url) {
				$body = str_replace(unicodify($url), $url, $body);
			}
		}
	}
	
	// replace tabs with 8 spaces
	$body = str_replace("\t", '        ', $body);
	
	$tracked_cites = array();
	
	// Cites
	if (isset($board) && preg_match_all('/(^|\s)&gt;&gt;(\d+?)([\s,.)?]|$)/m', $body, $cites, PREG_SET_ORDER | PREG_OFFSET_CAPTURE)) {		
		if (count($cites[0]) > $config['max_cites']) {
			error($config['error']['toomanycites']);
		}
		
		$skip_chars = 0;
		$body_tmp = $body;
		
		foreach ($cites as $matches) {
			$cite = $matches[2][0];
			$query = prepare(sprintf("SELECT `thread`,`id` FROM `posts_%s` WHERE `id` = :id LIMIT 1", $board['uri']));
			$query->bindValue(':id', $cite);
			$query->execute() or error(db_error($query));
			
			// preg_match_all is not multibyte-safe
			foreach ($matches as &$match) {
				$match[1] = mb_strlen(substr($body_tmp, 0, $match[1]));
			}
			
			if ($post = $query->fetch()) {
				$replacement = '<a onclick="highlightReply(\''.$cite.'\');" href="' .
					$config['root'] . $board['dir'] . $config['dir']['res'] . ($post['thread']?$post['thread']:$post['id']) . '.html#' . $cite . '">' .
						'&gt;&gt;' . $cite .
						'</a>';
				
				$body = mb_substr_replace($body, $matches[1][0] . $replacement . $matches[3][0], $matches[0][1] + $skip_chars, mb_strlen($matches[0][0]));
				$skip_chars += mb_strlen($matches[1][0] . $replacement . $matches[3][0]) - mb_strlen($matches[0][0]);
												
				if ($track_cites && $config['track_cites'])
					$tracked_cites[] = array($board['uri'], $post['id']);
			}
		}
	}
	
	// Cross-board linking
	if (preg_match_all('/(^|\s)&gt;&gt;&gt;\/(' . $config['board_regex'] . 'f?)\/(\d+)?([\s,.)?]|$)/um', $body, $cites, PREG_SET_ORDER | PREG_OFFSET_CAPTURE)) {
		if (count($cites[0]) > $config['max_cites']) {
			error($config['error']['toomanycross']);
		}
		
		$skip_chars = 0;
		$body_tmp = $body;
		
		foreach ($cites as $matches) {
			$_board = $matches[2][0];
			$cite = @$matches[3][0];
			
			// preg_match_all is not multibyte-safe
			foreach ($matches as &$match) {
				$match[1] = mb_strlen(substr($body_tmp, 0, $match[1]));
			}
			
			// Temporarily store board information because it will be overwritten
			$tmp_board = $board['uri'];
			
			// Check if the board exists, and load settings
			if (openBoard($_board)) {
				if ($cite) {
					$query = prepare(sprintf("SELECT `thread`,`id` FROM `posts_%s` WHERE `id` = :id LIMIT 1", $board['uri']));
					$query->bindValue(':id', $cite);
					$query->execute() or error(db_error($query));
					
					if ($post = $query->fetch()) {
						$replacement = '<a onclick="highlightReply(\''.$cite.'\');" href="' .
							$config['root'] . $board['dir'] . $config['dir']['res'] . ($post['thread']?$post['thread']:$post['id']) . '.html#' . $cite . '">' .
								'&gt;&gt;&gt;/' . $_board . '/' . $cite .
								'</a>';
						
						$body = mb_substr_replace($body, $matches[1][0] . $replacement . $matches[4][0], $matches[0][1] + $skip_chars, mb_strlen($matches[0][0]));
						$skip_chars += mb_strlen($matches[1][0] . $replacement . $matches[4][0]) - mb_strlen($matches[0][0]);
						
						if ($track_cites && $config['track_cites'])
							$tracked_cites[] = array($board['uri'], $post['id']);
					}
				} else {
					$replacement = '<a href="' .
						$config['root'] . $board['dir'] . $config['file_index'] . '">' .
							'&gt;&gt;&gt;/' . $_board . '/' .
							'</a>';
					$body = mb_substr_replace($body, $matches[1][0] . $replacement . $matches[4][0], $matches[0][1] + $skip_chars, mb_strlen($matches[0][0]));
					$skip_chars += mb_strlen($matches[1][0] . $replacement . $matches[4][0]) - mb_strlen($matches[0][0]);
				}
			}
			
			// Restore main board settings
			openBoard($tmp_board);
		}
	}
	
	$body = preg_replace("/^\s*&gt;.*$/m", '<span class="quote">$0</span>', $body);
	
	if ($config['strip_superfluous_returns'])
		$body = preg_replace('/\s+$/', '', $body);
	
	$body = preg_replace("/\n/", '<br/>', $body);
	
	return $tracked_cites;
}

function utf8tohtml($utf8) {
	return htmlspecialchars($utf8, ENT_NOQUOTES, 'UTF-8');
}

function ordutf8($string, &$offset) {
	$code = ord(substr($string, $offset,1)); 
	if ($code >= 128) { // otherwise 0xxxxxxx
		if ($code < 224)
			$bytesnumber = 2; // 110xxxxx
		else if ($code < 240)
			$bytesnumber = 3; // 1110xxxx
		else if ($code < 248)
			$bytesnumber = 4; // 11110xxx
		$codetemp = $code - 192 - ($bytesnumber > 2 ? 32 : 0) - ($bytesnumber > 3 ? 16 : 0);
		for ($i = 2; $i <= $bytesnumber; $i++) {
			$offset ++;
			$code2 = ord(substr($string, $offset, 1)) - 128; //10xxxxxx
			$codetemp = $codetemp*64 + $code2;
		}
		$code = $codetemp;
	}
	$offset += 1;
	if ($offset >= strlen($string))
		$offset = -1;
	return $code;
}

function strip_combining_chars($str) {
	$chars = preg_split('//u', $str, -1, PREG_SPLIT_NO_EMPTY);
	$str = '';
	foreach ($chars as $char) {
		$o = 0;
		$ord = ordutf8($char, $o);
		
		if ($ord >= 768 && $ord <= 879)
			continue;
		
		if ($ord >= 7616 && $ord <= 7679)
			continue;
		
		if ($ord >= 8400 && $ord <= 8447)
			continue;
		
		if ($ord >= 65056 && $ord <= 65071)
			continue;
		
		$str .= $char;
	}
	return $str;
}

function buildThread($id, $return = false, $mod = false) {
	global $board, $config;
	$id = round($id);
	
	if (event('build-thread', $id))
		return;
	
	if ($config['cache']['enabled'] && !$mod) {
		// Clear cache
		cache::delete("thread_index_{$board['uri']}_{$id}");
		cache::delete("thread_{$board['uri']}_{$id}");
	}
	
	$query = prepare(sprintf("SELECT * FROM `posts_%s` WHERE (`thread` IS NULL AND `id` = :id) OR `thread` = :id ORDER BY `thread`,`id`", $board['uri']));
	$query->bindValue(':id', $id, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	while ($post = $query->fetch()) {
		if (!isset($thread)) {
			$thread = new Thread(
				$post['id'], $post['subject'], $post['email'], $post['name'], $post['trip'], $post['capcode'], $post['body'], $post['time'],
				$post['thumb'], $post['thumbwidth'], $post['thumbheight'], $post['file'], $post['filewidth'], $post['fileheight'], $post['filesize'],
				$post['filename'], $post['ip'], $post['sticky'], $post['locked'], $post['sage'], $post['embed'], $mod ? '?/' : $config['root'], $mod
			);
		} else {
			$thread->add(new Post(
				$post['id'], $thread->id, $post['subject'], $post['email'], $post['name'], $post['trip'], $post['capcode'], $post['body'],
				$post['time'], $post['thumb'], $post['thumbwidth'], $post['thumbheight'], $post['file'], $post['filewidth'], $post['fileheight'],
				$post['filesize'], $post['filename'], $post['ip'], $post['embed'], $mod ? '?/' : $config['root'], $mod)
			);
		}
	}
	
	// Check if any posts were found
	if (!isset($thread))
		error($config['error']['nonexistant']);
	
	$body = Element('thread.html', array(
		'board' => $board,
		'thread' => $thread,
		'body' => $thread->build(),
		'config' => $config,
		'id' => $id,
		'mod' => $mod,
		'antibot' => $mod ? false : create_antibot($board['uri'], $id),
		'boardlist' => createBoardlist($mod),
		'return' => ($mod ? '?' . $board['url'] . $config['file_index'] : $config['root'] . $board['uri'] . '/' . $config['file_index'])
	));

	if ($return)
		return $body;

	file_write($board['dir'] . $config['dir']['res'] . sprintf($config['file_page'], $id), $body);
}

 function rrmdir($dir) {
	if (is_dir($dir)) {
		$objects = scandir($dir);
		foreach ($objects as $object) {
			if ($object != "." && $object != "..") {
				if (filetype($dir."/".$object) == "dir")
					rrmdir($dir."/".$object);
				else
					file_unlink($dir."/".$object);
			}
		}
		reset($objects);
		rmdir($dir);
	}
}

function poster_id($ip, $thread) {
	global $config;
	
	if ($id = event('poster-id', $ip, $thread))
		return $id;
	
	// Confusing, hard to brute-force, but simple algorithm
	return substr(sha1(sha1($ip . $config['secure_trip_salt'] . $thread) . $config['secure_trip_salt']), 0, $config['poster_id_length']);
}

function generate_tripcode($name) {
	global $config;
	
	if ($trip = event('tripcode', $name))
		return $trip;
	
	if (!preg_match('/^([^#]+)?(##|#)(.+)$/', $name, $match))
		return array($name);
	
	$name = $match[1];
	$secure = $match[2] == '##';
	$trip = $match[3];
	
	// convert to SHIT_JIS encoding
	$trip = mb_convert_encoding($trip, 'Shift_JIS', 'UTF-8');
	
	// generate salt
	$salt = substr($trip . 'H..', 1, 2);
	$salt = preg_replace('/[^\.-z]/', '.', $salt);
	$salt = strtr($salt, ':;<=>?@[\]^_`', 'ABCDEFGabcdef');
	
	if ($secure) {
		if (isset($config['custom_tripcode']["##{$trip}"]))
			$trip = $config['custom_tripcode']["##{$trip}"];
		else
			$trip = '!!' . substr(crypt($trip, $config['secure_trip_salt']), -10);
	} else {
		if (isset($config['custom_tripcode']["#{$trip}"]))
			$trip = $config['custom_tripcode']["#{$trip}"];
		else
			$trip = '!' . substr(crypt($trip, $salt), -10);
	}
	
	return array($name, $trip);
}
	
// Highest common factor
function hcf($a, $b){
	$gcd = 1;
	if ($a>$b) {
		$a = $a+$b;
		$b = $a-$b;
		$a = $a-$b;
	}
	if ($b==(round($b/$a))*$a) 
		$gcd=$a;
	else {
		for ($i=round($a/2);$i;$i--) {
			if ($a == round($a/$i)*$i && $b == round($b/$i)*$i) {
				$gcd = $i;
				$i = false;
			}
		}
	}
	return $gcd;
}

function fraction($numerator, $denominator, $sep) {
	$gcf = hcf($numerator, $denominator);
	$numerator = $numerator / $gcf;
	$denominator = $denominator / $gcf;
	
	return "{$numerator}{$sep}{$denominator}";
}

function getPostByHash($hash) {
	global $board;
	$query = prepare(sprintf("SELECT `id`,`thread` FROM `posts_%s` WHERE `filehash` = :hash", $board['uri']));
	$query->bindValue(':hash', $hash, PDO::PARAM_STR);
	$query->execute() or error(db_error($query));
	
	if ($post = $query->fetch()) {
		return $post;
	}
	
	return false;
}

function getPostByHashInThread($hash, $thread) {
	global $board;
	$query = prepare(sprintf("SELECT `id`,`thread` FROM `posts_%s` WHERE `filehash` = :hash AND ( `thread` = :thread OR `id` = :thread )", $board['uri']));
	$query->bindValue(':hash', $hash, PDO::PARAM_STR);
	$query->bindValue(':thread', $thread, PDO::PARAM_INT);
	$query->execute() or error(db_error($query));
	
	if ($post = $query->fetch()) {
		return $post;
	}
	
	return false;
}

function undoImage(array $post) {
	if (!$post['has_file'])
		return;
	
	if (isset($post['file']))
		file_unlink($post['file']);
	if (isset($post['thumb']))
		file_unlink($post['thumb']);
}

function rDNS($ip_addr) {
	global $config;
	
	if ($config['cache']['enabled'] && ($host = cache::get('rdns_' . $ip_addr))) {
		return $host;
	}
	
	if (!$config['dns_system']) {
		$host = gethostbyaddr($ip_addr);
	} else {
		$resp = shell_exec('host -W 1 ' . $ip_addr);
		if (preg_match('/domain name pointer ([^\s]+)$/', $resp, $m))
			$host = $m[1];
		else
			$host = $ip_addr;
	}
	
	if ($config['cache']['enabled'])
		cache::set('rdns_' . $ip_addr, $host, 3600);
	
	return $host;
}

function DNS($host) {
	global $config;
	
	if ($config['cache']['enabled'] && ($ip_addr = cache::get('dns_' . $host))) {
		return $ip_addr;
	}
	
	if (!$config['dns_system']) {
		$ip_addr = gethostbyname($host);
		if ($ip_addr == $host)
			$ip_addr = false;
	} else {
		$resp = shell_exec('host -W 1 ' . $host);
		if (preg_match('/has address ([^\s]+)$/', $resp, $m))
			$ip_addr = $m[1];
		else
			$ip_addr = false;
	}
	
	if ($config['cache']['enabled'])
		cache::set('dns_' . $host, $ip_addr, 3600);
	
	return $ip_addr;
}