<?php
//check PHP version
if (version_compare(PHP_VERSION, '5.3.3', '<')) {
	die('PHP >=5.3.3 version required.');
}

require_once(SG_EXCEPTION_PATH.'SGException.php');
require_once(SG_CORE_PATH.'functions.php');
@include_once(SG_CORE_PATH.'functions.silver.php');
@include_once(SG_CORE_PATH.'functions.gold.php');
@include_once(SG_CORE_PATH.'functions.platinum.php');
require_once(SG_CORE_PATH.'SGPing.php');
require_once(SG_DATABASE_PATH.'SGDatabase.php');
require_once(SG_CORE_PATH.'SGConfig.php');
require_once(SG_NOTICE_PATH.'SGNotice.php');
require_once(SG_NOTICE_PATH.'SGNoticeHandler.php');
@include_once(SG_BACKUP_PATH.'SGBackupSchedule.php');
@include_once(SG_EXTENSION_PATH.'SGExtension.php');

class SGBoot
{
	public static $executionTimeLimit = 0;
	public static $memoryLimit = 0;

	public static function init()
	{
		//get current execution time limit
		self::$executionTimeLimit = ini_get('max_execution_time');

		//get current memory limit
		self::$memoryLimit = ini_get('memory_limit');

		//remove execution time limit
		@set_time_limit(0);

		//change initial memory limit
		@ini_set('memory_limit', '512M');

		//don't let server to abort scripts
		@ignore_user_abort(true);

		//load all config variables from database
		SGConfig::getAll();

		try {
			//check minimum requirements
			self::checkMinimumRequirements();

			//prepare directory for backups
			self::prepare();
		}
		catch (SGException $exception) {
			die($exception);
		}
	}

	public static function didInstallForFirstTime()
	{
		self::setPluginInstallUpdateDate();
	}

	public static function didUpdatePluginVersion()
	{
		self::setPluginInstallUpdateDate();
	}

	public static function setPluginInstallUpdateDate()
	{
		SGConfig::set('SG_PLUGIN_INSTALL_UPDATE_DATE', time());
	}

	private static function installConfigTable($sgdb)
	{
		//drop config table
		$sgdb->query('DROP TABLE IF EXISTS `'.SG_CONFIG_TABLE_NAME.'`;');

		//create config table
		$res = $sgdb->query(
			'CREATE TABLE IF NOT EXISTS `'.SG_CONFIG_TABLE_NAME.'` (
			  `ckey` varchar(100) NOT NULL,
			  `cvalue` text NOT NULL,
			  PRIMARY KEY (`ckey`)
			) DEFAULT CHARSET=utf8;'
		);
		if ($res===false) {
			return false;
		}

		//delete all content from config table (just in case if wasn't dropped)
		$sgdb->query('DELETE FROM `'.SG_CONFIG_TABLE_NAME.'`;');

		//populate config table
		$res = $sgdb->query(
			"INSERT INTO `".SG_CONFIG_TABLE_NAME."` VALUES
			('SG_BACKUP_GUARD_VERSION','".SG_BACKUP_GUARD_VERSION."'),
			('SG_BACKUP_WITH_RELOADINGS', '1'),
			('SG_BACKUP_SYNCHRONOUS_STORAGE_UPLOAD','1'),
			('SG_NOTIFICATIONS_ENABLED','0'),
			('SG_SHOW_STATISTICS_WIDGET','1'),
			('SG_NOTIFICATIONS_EMAIL_ADDRESS',''),
			('SG_STORAGE_BACKUPS_FOLDER_NAME','sg_backups');"
		);
		if ($res===false) {
			return false;
		}

		return true;
	}

	private static function installScheduleTable($sgdb)
	{
		//drop schedule table
		$sgdb->query('DROP TABLE IF EXISTS `'.SG_SCHEDULE_TABLE_NAME.'`;');

		//create schedule table
		$res = $sgdb->query(
			'CREATE TABLE IF NOT EXISTS `'.SG_SCHEDULE_TABLE_NAME.'` (
			  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
			  `label` varchar(255) NOT NULL,
			  `status` tinyint(3) unsigned NOT NULL,
			  `schedule_options` varchar(255) NOT NULL,
			  `backup_options` text NOT NULL,
			  PRIMARY KEY (`id`)
			) DEFAULT CHARSET=utf8;'
		);
		if ($res===false) {
			return false;
		}

		return true;
	}

	private static function installActionTable($sgdb)
	{
		//drop action table
		$sgdb->query('DROP TABLE IF EXISTS `'.SG_ACTION_TABLE_NAME.'`;');

		//create action table
		$res = $sgdb->query(
			"CREATE TABLE IF NOT EXISTS `".SG_ACTION_TABLE_NAME."` (
			  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
			  `name` varchar(255) NOT NULL,
			  `type` tinyint(3) unsigned NOT NULL,
			  `subtype` tinyint(3) unsigned NOT NULL DEFAULT '0',
			  `status` tinyint(3) unsigned NOT NULL,
			  `progress` tinyint(3) unsigned NOT NULL DEFAULT '0',
			  `start_date` datetime NOT NULL,
			  `update_date` datetime DEFAULT NULL,
			  `options` text NOT NULL,
			  PRIMARY KEY (`id`)
			) DEFAULT CHARSET=utf8;"
		);
		if ($res===false) {
			return false;
		}

		return true;
	}

	public static function install()
	{
		$sgdb = SGDatabase::getInstance();

		try {
			if (!self::installConfigTable($sgdb)) {
				throw new SGExceptionDatabaseError('Could not install config table');
			}

			if (!self::installScheduleTable($sgdb)) {
				throw new SGExceptionDatabaseError('Could not install schedule table');
			}

			if (!self::installActionTable($sgdb)) {
				throw new SGExceptionDatabaseError('Could not install action table');
			}
		}
		catch (SGException $exception) {
			die($exception);
		}
	}

	private static function cleanupSchedules()
	{
		$schedules = SGBackupSchedule::getAllSchedules();
		foreach ($schedules as $schedule) {
			SGBackupSchedule::remove($schedule['id']);
		}
	}

	public static function uninstall($deleteBackups = false)
	{
		try {
			@unlink(SG_PING_FILE_PATH);

			if (self::isFeatureAvailable('SCHEDULE')) {
				self::cleanupSchedules();
			}

			$sgdb = SGDatabase::getInstance();

			//drop config table
			$res = $sgdb->query('DROP TABLE IF EXISTS `'.SG_CONFIG_TABLE_NAME.'`;');
			if ($res===false) {
				throw new SGExceptionDatabaseError('Could not execute query');
			}

			//drop schedule table
			$res = $sgdb->query('DROP TABLE IF EXISTS `'.SG_SCHEDULE_TABLE_NAME.'`;');
			if ($res===false) {
				throw new SGExceptionDatabaseError('Could not execute query');
			}

			//drop action table
			$res = $sgdb->query('DROP TABLE IF EXISTS `'.SG_ACTION_TABLE_NAME.'`;');
			if ($res===false) {
				throw new SGExceptionDatabaseError('Could not execute query');
			}

			//delete directory of backups
			if ($deleteBackups) {
				$backupPath = SGConfig::get('SG_BACKUP_DIRECTORY');
				backupGuardDeleteDirectory($backupPath);
			}
		}
		catch (SGException $exception) {
			die($exception);
		}
	}

	public static function checkRequirement($requirement)
	{
		if ($requirement=='ftp' && !extension_loaded('ftp')) {
			throw new SGExceptionNotFound('FTP extension is not loaded.');
		}
		else if ($requirement=='curl' && !function_exists('curl_version')) {
			throw new SGExceptionNotFound('cURL extension is not loaded.');
		}
		else if ($requirement=='intSize' && PHP_INT_SIZE < 8) {
			throw new SGExceptionIO("BackupGuard uses 64-bit integers, but it looks like we're running on a version of PHP that doesn't support 64-bit integers (PHP_INT_MAX=" . ((string) PHP_INT_MAX) . ")");
		}
	}

	public static function isFeatureAvailable($feature)
	{
		return (SGConfig::get('SG_FEATURE_'.strtoupper($feature))===1?true:false);
	}

	private static function prepare()
	{
		$backupPath = SGConfig::get('SG_BACKUP_DIRECTORY');

		//create directory for backups
		if (!is_dir($backupPath)) {
			if (!@mkdir($backupPath)) {
				throw new SGExceptionMethodNotAllowed('Cannot create folder: '.$backupPath);
			}

			if (!@file_put_contents($backupPath.'.htaccess', 'deny from all')) {
				throw new SGExceptionMethodNotAllowed('Cannot create htaccess file');
			}
		}

		//check permissions of backups directory
		if (!is_writable($backupPath)) {
			throw new SGExceptionForbidden('Permission denied. Directory is not writable: '.$backupPath);
		}

		//prepare notices
		$noticeHandler = new SGNoticeHandler();
		$noticeHandler->run();
	}

	private static function checkMinimumRequirements()
	{
		//check ZLib library
		if (!function_exists('gzdeflate')) {
			throw new SGExceptionNotFound('ZLib extension is not loaded.');
		}
	}
}
