<?php
/**
 * Akeeba Engine
 * The modular PHP5 site backup engine
 * @copyright Copyright (c)2009-2014 Nicholas K. Dionysopoulos
 * @license   GNU GPL version 3 or, at your option, any later version
 * @package   akeebaengine
 *
 */

// Protection against direct access
defined('AKEEBAENGINE') or die();

/* Windows system detection */
if (!defined('_AKEEBA_IS_WINDOWS'))
{
	if (function_exists('php_uname'))
	{
		define('_AKEEBA_IS_WINDOWS', stristr(php_uname(), 'windows'));
	}
	else
	{
		define('_AKEEBA_IS_WINDOWS', DIRECTORY_SEPARATOR == '\\');
	}
}

/**
 * A filesystem scanner which uses opendir() and is smart enough to make large directories
 * be scanned inside a step of their own.
 *
 * The idea is that if it's not the first operation of this step and the number of contained
 * directories AND files is more than double the number of allowed files per fragment, we should
 * break the step immediately.
 *
 */
class AEScanSmart extends AEAbstractScan
{
	private $method = 'opendir';

	public function __construct()
	{
		parent::__construct();

		$this->method = AEFactory::getConfiguration()->get('engine.scan.smart.scan_method', 'opendir');
	}

	public function &getFiles($folder, &$position)
	{
		$registry = AEFactory::getConfiguration();
		// Was the breakflag set BEFORE starting? -- This workaround is required due to PHP5 defaulting to assigning variables by reference
		$breakflag_before_process = $registry->get('volatile.breakflag', false);

		// Reset break flag before continuing
		$breakflag = false;

		// Initialize variables
		$arr = array();
		$false = false;

		if (!is_dir($folder) && !is_dir($folder . '/'))
		{
			return $false;
		}

		$counter = 0;
		$registry = AEFactory::getConfiguration();
		$maxCounter = $registry->get('engine.scan.smart.large_dir_threshold', 100);

		$allowBreakflag = ($registry->get('volatile.operation_counter', 0) != 0) && !$breakflag_before_process;

		if ($this->method == 'opendir')
		{
			$handle = @opendir($folder);
			/* If opening the directory doesn't work, try adding a trailing slash. This is useful in cases
			 * like this: open_basedir=/home/user/www/ and the root is /home/user/www. Trying to scan
			 * /home/user/www results in error, trying to scan /home/user/www/ succeeds. Duh!
			 */
			if ($handle === false)
			{
				$handle = @opendir($folder . '/');
			}
			// If directory is not accessible, just return FALSE
			if ($handle === false)
			{
				$this->setWarning('Unreadable directory ' . $folder);

				return $false;
			}
		}
		else
		{
			$handle = dir($folder);
			if ($handle->handle === false)
			{
				$handle = dir($folder . '/');
				if ($handle->handle === false)
				{
					$this->setWarning('Unreadable directory ' . $folder);

					return $false;
				}
			}
		}

		while ((($file = ($this->method == 'opendir' ? @readdir($handle) : $handle->read())) !== false) && (!$breakflag))
		{
			if (($file != '.') && ($file != '..'))
			{
				// # Fix 2.4.b1: Do not add DS if we are on the site's root and it's an empty string
				// # Fix 2.4.b2: Do not add DS is the last character _is_ DS
				$ds = ($folder == '') || ($folder == '/') || (@substr($folder, -1) == '/') || (@substr($folder, -1) == DIRECTORY_SEPARATOR) ? '' : DIRECTORY_SEPARATOR;
				$dir = $folder . $ds . $file;
				$isDir = is_dir($dir);
				if (!$isDir)
				{
					$data = _AKEEBA_IS_WINDOWS ? AEUtilFilesystem::TranslateWinPath($dir) : $dir;
					if ($data)
					{
						$arr[] = $data;
					}
				}
			}
			$counter++;
			if ($counter >= $maxCounter)
			{
				$breakflag = $allowBreakflag;
			}
		}
		$this->method == 'opendir' ? @closedir($handle) : $handle->close();

		// Save break flag status
		$registry->set('volatile.breakflag', $breakflag);

		return $arr;
	}

	public function &getFolders($folder, &$position)
	{
		// Was the breakflag set BEFORE starting? -- This workaround is required due to PHP5 defaulting to assigning variables by reference
		$registry = AEFactory::getConfiguration();
		$breakflag_before_process = $registry->get('volatile.breakflag', false);

		// Reset break flag before continuing
		$breakflag = false;

		// Initialize variables
		$arr = array();
		$false = false;

		if (!is_dir($folder) && !is_dir($folder . '/'))
		{
			return $false;
		}

		$counter = 0;
		$registry = AEFactory::getConfiguration();
		$maxCounter = $registry->get('engine.scan.smart.large_dir_threshold', 100);

		$allowBreakflag = ($registry->get('volatile.operation_counter', 0) != 0) && !$breakflag_before_process;

		if ($this->method == 'opendir')
		{
			$handle = @opendir($folder);
			/* If opening the directory doesn't work, try adding a trailing slash. This is useful in cases
			 * like this: open_basedir=/home/user/www/ and the root is /home/user/www. Trying to scan
			 * /home/user/www results in error, trying to scan /home/user/www/ succeeds. Duh!
			 */
			if ($handle === false)
			{
				$handle = @opendir($folder . '/');
			}
			// If directory is not accessible, just return FALSE
			if ($handle === false)
			{
				$this->setWarning('Unreadable directory ' . $folder);

				return $false;
			}
		}
		else
		{
			$handle = dir($folder);
			if ($handle->handle === false)
			{
				$handle = dir($folder . '/');
				if ($handle->handle === false)
				{
					$this->setWarning('Unreadable directory ' . $folder);

					return $false;
				}
			}
		}

		while ((($file = ($this->method == 'opendir' ? @readdir($handle) : $handle->read())) !== false) && (!$breakflag))
		{
			if (($file != '.') && ($file != '..'))
			{
				// # Fix 2.4: Do not add DS if we are on the site's root and it's an empty string
				$ds = ($folder == '') || ($folder == '/') || (@substr($folder, -1) == '/') || (@substr($folder, -1) == DIRECTORY_SEPARATOR) ? '' : DIRECTORY_SEPARATOR;
				$dir = $folder . $ds . $file;
				$isDir = is_dir($dir);
				if ($isDir)
				{
					$data = _AKEEBA_IS_WINDOWS ? AEUtilFilesystem::TranslateWinPath($dir) : $dir;
					if ($data)
					{
						$arr[] = $data;
					}
				}
			}
			$counter++;
			if ($counter >= $maxCounter)
			{
				$breakflag = $allowBreakflag;
			}
		}
		$this->method == 'opendir' ? @closedir($handle) : $handle->close();

		// Save break flag status
		$registry->set('volatile.breakflag', $breakflag);

		return $arr;
	}
}