<?php
/**
 * @author Martin Dougiamas
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package moodle multiauth
 *
 * Multiple plugin authentication
 * Support library
 *
 * 2006-08-28  File created, AUTH return values defined.
 */

/**
 * Returned when the login was successful.
 */
define('AUTH_OK',     0);

/**
 * Returned when the login was unsuccessful.
 */
define('AUTH_FAIL',   1);

/**
 * Returned when the login was denied (a reason for AUTH_FAIL).
 */
define('AUTH_DENIED', 2);

/**
 * Returned when some error occurred (a reason for AUTH_FAIL).
 */
define('AUTH_ERROR',  4);

/**
 * Authentication - error codes for user confirm
 */
define('AUTH_CONFIRM_FAIL', 0);
define('AUTH_CONFIRM_OK', 1);
define('AUTH_CONFIRM_ALREADY', 2);
define('AUTH_CONFIRM_ERROR', 3);


/**
 * Abstract authentication plugin.
 */
class auth_plugin_base {

    /**
     * The configuration details for the plugin.
     */
    var $config;

    /**
     * Authentication plugin type - the same as db field.
     */
    var $authtype;

    /**
     * Returns true if the username and password work and false if they are
     * wrong or don't exist.
     *
     * @param string $username The username (with system magic quotes)
     * @param string $password The password (with system magic quotes)
     *
     * @return bool Authentication success or failure.
     */
    function user_login($username, $password) {
        error('Abstract user_login() method must be overriden.');
    }

    /**
     * Returns true if this authentication plugin can change the user's
     * password.
     *
     * @return bool
     */
    function can_change_password() {
        //override if needed
        return false;
    }

    /**
     * Returns the URL for changing the user's pw, or empty if the default can
     * be used.
     *
     * @return string
     */
    function change_password_url() {
        //override if needed
        return '';
    }

    /**
     * Returns true if this authentication plugin is 'internal'.
     *
     * @return bool
     */
    function is_internal() {
        //override if needed
        return true;
    }

    /**
     * Change a user's password
     *
     * @param  object  $user        User table object  (with system magic quotes)
     * @param  string  $newpassword Plaintext password (with system magic quotes)
     *
     * @return bool                  True on success
     */
    function user_update_password($user, $newpassword) {
        //override if needed
        return true;
    }

    /**
     * Called when the user record is updated.
     * Modifies user in external database. It takes olduser (before changes) and newuser (after changes)
     * conpares information saved modified information to external db.
     *
     * @param mixed $olduser     Userobject before modifications    (without system magic quotes)
     * @param mixed $newuser     Userobject new modified userobject (without system magic quotes)
     * @return boolean true if updated or update ignored; false if error
     *
     */
    function user_update($olduser, $newuser) {
        //override if needed
        return true;
    }

    /**
     * Returns true if plugin allows resetting of internal password.
     *
     * @return bool
     */
    function can_reset_password() {
        //override if needed
        return false;
    }

    /**
     * Returns true if plugin allows resetting of internal password.
     *
     * @return bool
     */
    function can_signup() {
        //override if needed
        return false;
    }

    /**
     * Sign up a new user ready for confirmation.
     * Password is passed in plaintext.
     *
     * @param object $user new user object (with system magic quotes)
     * @param boolean $notify print notice with link and terminate
     */
    function user_signup($user, $notify=true) {
        //override when can signup
        error('user_signup method must be overriden if signup enabled');
    }

    /**
     * Returns true if plugin allows confirming of new users.
     *
     * @return bool
     */
    function can_confirm() {
        //override if needed
        return false;
    }

    /**
     * Confirm the new user as registered.
     *
     * @param string $username (with system magic quotes)
     * @param string $confirmsecret (with system magic quotes)
     */
    function user_confirm($username, $confirmsecret) {
        //override when can confirm
        error('user_confirm method must be overriden if confirm enabled');
    }

    /**
     * Checks if user exists in external db
     *
     * @param string $username (with system magic quotes)
     */
    function user_exists() {
        //override if needed
        return false;
    }

    /**
     * Activates (enables) user in external db so user can login using username/password from external db
     *
     * @param mixed $username    username (with system magic quotes)
     * @return boolen result
     */
    function user_activate($username) {
        //override if needed
        return true;
    }

    /**
     * return number of days to user password expires
     *
     * If userpassword does not expire it should return 0. If password is already expired
     * it should return negative value.
     *
     * @param mixed $username username (with system magic quotes)
     * @return integer
     */
    function password_expire($username) {
        return 0;
    }
    /**
     * Sync roles for this user - usually creator
     *
     * @param $user object user object (without system magic quotes)
     */
    function sync_roles($user) {
        //override if needed
    }

    /**
     * Read user information from external database and returns it as array().
     * Function should return all information available. If you are saving
     * this information to moodle user-table you should honor syncronization flags
     *
     * @param string $username username (with system magic quotes)
     *
     * @return mixed array with no magic quotes or false on error
     */
    function get_userinfo($username) {
        //override if needed
        return array();
    }

    /**
     * A chance to validate form data, and last chance to
     * do stuff before it is inserted in config_plugin
     */
     function validate_form(&$form, &$err) {
        //override if needed
    }

    /**
     * Prelogin actions.
     */
    function prelogin_hook() {
        //override if needed
    }

    /**
     * Post authentication hook.
     */
    function user_authenticated_hook($user, $username, $password) {
    /// TODO: review following code - looks hackish :-( mnet should obsole this, right?
    /// Log in to a second system if necessary
        global $CFG;

        if (!empty($CFG->sso)) {
            include_once($CFG->dirroot .'/sso/'. $CFG->sso .'/lib.php');
            if (function_exists('sso_user_login')) {
                if (!sso_user_login($username, $password)) {   // Perform the signon process
                    notify('Second sign-on failed');
                }
            }
        }
    }

    /**
     * Prelogout actions.
     */
    function prelogout_hook() {
        //override if needed
    }
}

?>