<?php namespace Laravel\Session\Drivers;

class File extends Driver implements Sweeper {

	/**
	 * The path to which the session files should be written.
	 *
	 * @var string
	 */
	private $path;

	/**
	 * Create a new File session driver instance.
	 *
	 * @param  string        $path
	 * @return void
	 */
	public function __construct($path)
	{
		$this->path = $path;
	}

	/**
	 * Load a session from storage by a given ID.
	 *
	 * If no session is found for the ID, null will be returned.
	 *
	 * @param  string  $id
	 * @return array
	 */
	public function load($id)
	{
		if (file_exists($path = $this->path.$id))
		{
			return unserialize(file_get_contents($path));
		}
	}

	/**
	 * Save a given session to storage.
	 *
	 * @param  array  $session
	 * @param  array  $config
	 * @param  bool   $exists
	 * @return void
	 */
	public function save($session, $config, $exists)
	{
		file_put_contents($this->path.$session['id'], serialize($session), LOCK_EX);
	}

	/**
	 * Delete a session from storage by a given ID.
	 *
	 * @param  string  $id
	 * @return void
	 */
	public function delete($id)
	{
		if (file_exists($this->path.$id))
		{
			@unlink($this->path.$id);
		}
	}

	/**
	 * Delete all expired sessions from persistant storage.
	 *
	 * @param  int   $expiration
	 * @return void
	 */
	public function sweep($expiration)
	{
		$files = glob($this->path.'*');

		if ($files === false) return;

		foreach ($files as $file)
		{
			if (filetype($file) == 'file' and filemtime($file) < $expiration)
			{
				@unlink($file);
			}
		}
	}
	
}