<?php
	/* libraries/session.php
	 *
	 * Copyright (C) by Hugo Leisink <hide@address.com>
	 * This file is part of the Banshee PHP framework
	 * http://www.banshee-php.org/
	 *
	 * Don't change this file, unless you know what you are doing.
	 */

	final class session {
		private $db = null;
		private $settings = null;
		private $id = null;
		private $session_id = null;
		private $use_database = null;

		/* Constructor
		 *
		 * INPUT:  object database
		 * OUTPUT: -
		 * ERROR:  -
		 */
		public function __construct($db, $settings) {
			$this->db = $db;
			$this->settings = $settings;

			$this->db->query("delete from sessions where expire<=now()");

			$this->use_database = (SESSION_TIMEOUT >= ini_get("session.gc_maxlifetime"));

			$this->start();

			if ($this->use_database == false) {
				return;
			}

			$query = "select * from sessions where session_id=%s";
			if (($result = $this->db->execute($query, $this->session_id)) == false) {
				/* New session
				 */
				$session_data = array(
					"id"         => null,
					"session_id" => $this->session_id,
					"content"    => null,
					"expire"     => date("Y-m-d H:i:s", time() + SESSION_TIMEOUT),
					"user_id"    => null,
					"ip_address" => $_SERVER["REMOTE_ADDR"],
					"name"       => null);
				$this->db->insert("sessions", $session_data);

				$this->id = $this->db->last_insert_id;
			} else {
				/* Existing session
				 */
				$this->id = (int)$result[0]["id"];
				$_SESSION = json_decode($result[0]["content"], true);
			}
		}

		/* Destructor
		 *
		 * INPUT:  -
		 * OUTPUT: -
		 * ERROR:  -
		 */
		public function __destruct() {
			if ($this->use_database == false) {
				return;
			}

			$session_data = array(
				"content"    => json_encode($_SESSION),
				"expire"     => date("Y-m-d H:i:s", time() + SESSION_TIMEOUT),
				"ip_address" => $_SERVER["REMOTE_ADDR"]);

			$this->db->update("sessions", $this->id, $session_data);

			$_SESSION = array();
		}

		/* Start session
		 *
		 * INPUT:  -
		 * OUTPUT: -
		 * ERROR:  -
		 */
		public function start() {
			if ($this->use_database) {
				/* Use database
				 */
				if (isset($_COOKIE[SESSION_NAME]) == false) {
					$this->session_id = md5(time().$this->settings->secret_website_code);
					$timeout = is_true(SESSION_PERSISTENT) ? time() + SESSION_TIMEOUT : null;
					setcookie(SESSION_NAME, $this->session_id, $timeout);
					$_COOKIE[SESSION_NAME] = $this->session_id;
				} else {
					$this->session_id = $_COOKIE[SESSION_NAME];
				}
			} else {
				/* Use PHP's session handling 
				 */
				session_name(SESSION_NAME);
				if (is_true(SESSION_PERSISTENT)) {
					session_set_cookie_params(SESSION_TIMEOUT);
				}
				session_start();
				$this->session_id = session_id();
			}
		}

		/* Update user_id in session record
		 *
		 * INPUT:  int user id
		 * OUTPUT: true
		 * ERROR:  false
		 */
		public function set_user_id($user_id) {
			if ($this->use_database == false) {
				return true;
			}

			$user_data = array("user_id" => (int)$user_id);

			return $this->db->update("sessions", $this->id, $user_data) !== false;
		}

		/* Reset session
		 *
		 * INPUT:  -
		 * OUTPUT: -
		 * ERROR:  -
		 */
		public function reset() {
			unset($_COOKIE[SESSION_NAME]);
			$_SESSION = array();
			if ($this->use_database) {
				$this->db->query("delete from sessions where id=%s", $this->id);
			} else {
				session_destroy();
			}

			$this->start();
		}
	}
?>