Login library for CI

login.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**
 * CodeIgniter Login Class
 * This class enables you to have a simple login route and permission levels
 *
 * @package  	CodeIgniter
 * @subpackage	Libraries
 * @category	Libraries
 * @author		Weslley Araujo (http://weslleydeveloper.com)
 * @link http://pastebin.com/FJn3WhLg
 *
 *	@param $login_table_name
 *				your users table name on yout database
 *
 *	@param $login_user_field
 *				the name field on your table to compare with pass
 *
 *	@param $login_pass_field
 *				the password field on your table to compare with username ( require to be a md5 hash )
 *
 *	@param $login_session_name
 *				the name you want to save on the session
 *
 *	You can configure those itens ate your config.php file or using initialize method
 *		$config['login_table_name']   = '';
 *		$config['login_user_field']   = '';
 *		$config['login_pass_field']   = '';
 *		$config['login_session_name'] = '';
 *
 */

class Login
{
	protected $ci;

	private   $login_table_name;
	private   $login_user_field;
	private   $login_pass_field;
	private   $login_session_name;
	
	private   $config;

	public function __construct($config = array())
	{
		// get ci instance
        	$this->ci =& get_instance();

        	// initialize
        	$this->initialize($config);

        	// get user
        	$user = $this->checkUser();
	}

	/**
	 * Initialize preferences
	 *
	 * @param	array
	 * @return	void
	 */
	public function initialize($config = array())
	{
		$params = array(
			'login_table_name',
			'login_user_field',
			'login_pass_field',
			'login_session_name'
		);

		foreach ($params as $key => $value) {

			if (array_key_exists($value, $config)) {
				$this->$value = $config[$value];
			}
			else {
				$this->$value = $this->ci->config->item($value);
			}
		}
	}

	 /**
     	 * Get user session
    	 *
    	 * @return boolean user identification if user is logged, false if not
    	 *
    	 * @access private
    	 */
	public function checkUser()
	{
		return $this->ci->session->userdata($this->login_session_name);
	}
	
	 /**
	 * Hash user password
	 *
	 * @param string $pass  Password to hash
	 *
	 * @return string Password hashed;
	 * @access public
	 */
	public function hashPass($pass)
	{
		return md5($pass);
	}
	
	 /**
	 * Set user data
	 *
	 *	@param int|string userdata you want to save
	 *	
	 *	@return void
	 *  @access public
	 */
	private function setUser($user)
	{
		$this->ci->session->set_userdata($this->login_session_name, $user);
	}

	 /**
	 * Destroy user session
	 *
	 *	@return void
	 *  @access public
	 */
	public function destroy()
	{
		$this->ci->session->unset_userdata($this->login_session_name);
	}

	 /**
	 * Authenticate usar in database
	 *
	 *	@param string $user username to check
	 *	@param string $pass password to check
	 *
	 *	@return mixed 
	 *			array ( empty ) means false
	 *			objcet user info on database ( password return null for safe)
	 *  @access public
	 */
	public function authenticate($user = null, $pass = null)
	{
		$fields = array(
			$this->login_user_field => $user != null ? $user : $this->ci->input->post($this->login_user_field),
			$this->login_pass_field => $pass != null ? $this->hashPass($pass) : $this->hashPass($this->ci->input->post($this->login_pass_field))
		);
		$this->ci->db->where($fields);
		$get = $this->ci->db->get($this->login_table_name);
		$get = $get->row();
		if (is_object($get)) {	
			// clear password
			$get->{$this->login_pass_field} = null;
		}
		$this->setUser($get);
	}

	 /**
	 * Requires user authentication
	 *
	 * @param string $redirect page you want to redirect in case of fail authentication
	 *
	 * @access public
	 */
	public function requireLogin($redirect = '')
	{
		if(!$this->checkUser())
			redirect($redirect);

		return true;
	}

	 /**
	 * Not allow user get in page if is logged
	 *
	 * @param string $redirect page you want to redirect in case of user already logged
	 *
	 * @access public
	 */
	public function notAllowLogged($redirect = '')
	{
		if($this->checkUser())
			redirect($redirect);

		return true;
	}
}

/* End of file login.php */