<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * external API for mobile web services
 *
 * @package    core
 * @subpackage webservice
 * @copyright  2011 Moodle Pty Ltd (http://moodle.com)
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/**
 * Web service related functions
 */
class core_webservice_external extends external_api {

    /**
     * Returns description of method parameters
     * @return external_function_parameters
     */
    public static function get_site_info_parameters() {
        return new external_function_parameters(
            array('serviceshortnames' => new external_multiple_structure (
                new external_value(
                    PARAM_ALPHANUMEXT,
                    'service shortname'),
                    'DEPRECATED PARAMETER - it was a design error in the original implementation. It is ignored now. (parameter kept for backward compatibility)',
                    VALUE_DEFAULT,
                    array()
                ),
            )
        );
    }

    /**
     * Return user information including profile picture + basic site information
     * Note:
     * - no capability checking because we return just known information by logged user
     * @param array $serviceshortnames - DEPRECATED PARAMETER - values will be ignored - it was an original design error, we keep for backward compatibility.
     * @return array
     */
    public function get_site_info($serviceshortnames = array()) {
        global $USER, $SITE, $CFG, $DB;

        $params = self::validate_parameters(self::get_site_info_parameters(),
                      array('serviceshortnames'=>$serviceshortnames));

        $profileimageurl = moodle_url::make_pluginfile_url(
                get_context_instance(CONTEXT_USER, $USER->id)->id, 'user', 'icon', NULL, '/', 'f1');

        //site information
        $siteinfo =  array(
            'sitename' => $SITE->fullname,
            'siteurl' => $CFG->wwwroot,
            'username' => $USER->username,
            'firstname' => $USER->firstname,
            'lastname' => $USER->lastname,
            'fullname' => fullname($USER),
            'userid' => $USER->id,
            'userpictureurl' => $profileimageurl->out(false)
        );

        //Retrieve the service and functions from the web service linked to the token
        //If you call this function directly from external (not a web service call),
        //then it will still return site info without information about a service
        //Note: wsusername/wspassword ws authentication is not supported.
        $functions = array();
        if ($CFG->enablewebservices) { //no need to check token if web service are disabled and not a ws call
            $token = optional_param('wstoken', '', PARAM_ALPHANUM);

            if (!empty($token)) { //no need to run if not a ws call
                //retrieve service shortname
                $servicesql = 'SELECT s.*
                               FROM {external_services} s, {external_tokens} t
                               WHERE t.externalserviceid = s.id AND token = ? AND t.userid = ? AND s.enabled = 1';
                $service = $DB->get_record_sql($servicesql, array($token, $USER->id));

                $siteinfo['downloadfiles'] = $service->downloadfiles;

                if (!empty($service)) {
                    //retrieve the functions
                    $functionssql = "SELECT f.*
                            FROM {external_functions} f, {external_services_functions} sf
                            WHERE f.name = sf.functionname AND sf.externalserviceid = ?";
                    $functions = $DB->get_records_sql($functionssql, array($service->id));
                } else {
                    throw new coding_exception('No service found in get_site_info: something is buggy, it should have fail at the ws server authentication layer.');
                }
            }
        }

        //built up the returned values of the list of functions
        $componentversions = array();
        $avalaiblefunctions = array();
        foreach ($functions as $function) {
            $functioninfo = array();
            $functioninfo['name'] = $function->name;
            if ($function->component == 'moodle') {
                $version = $CFG->version; //moodle version
            } else {
                $versionpath = get_component_directory($function->component).'/version.php';
                if (is_readable($versionpath)) {
                    //we store the component version once retrieved (so we don't load twice the version.php)
                    if (!isset($componentversions[$function->component])) {
                        include($versionpath);
                        $componentversions[$function->component] = $plugin->version;
                        $version = $plugin->version;
                    } else {
                        $version = $componentversions[$function->component];
                    }
                } else {
                    //function component should always have a version.php,
                    //otherwise the function should have been described with component => 'moodle'
                    throw new moodle_exception('missingversionfile', 'webservice', '', $function->component);
                }
            }
            $functioninfo['version'] = $version;
            $avalaiblefunctions[] = $functioninfo;
        }

        $siteinfo['functions'] = $avalaiblefunctions;

        return $siteinfo;
    }

    /**
     * Returns description of method result value
     * @return external_single_structure
     */
    public static function get_site_info_returns() {
        return new external_single_structure(
            array(
                'sitename'       => new external_value(PARAM_RAW, 'site name'),
                'username'       => new external_value(PARAM_RAW, 'username'),
                'firstname'      => new external_value(PARAM_TEXT, 'first name'),
                'lastname'       => new external_value(PARAM_TEXT, 'last name'),
                'fullname'       => new external_value(PARAM_TEXT, 'user full name'),
                'userid'         => new external_value(PARAM_INT, 'user id'),
                'siteurl'        => new external_value(PARAM_RAW, 'site url'),
                'userpictureurl' => new external_value(PARAM_URL, 'the user profile picture.
                    Warning: this url is the public URL that only works when forcelogin is set to NO and guestaccess is set to YES.
                    In order to retrieve user profile pictures independently of the Moodle config, replace "pluginfile.php" by
                    "webservice/pluginfile.php?token=WSTOKEN&file=". Of course the user can only see profile picture depending on his/her permissions.
                    Moreover it is recommended to use HTTPS too.'),
                'functions'      => new external_multiple_structure(
                    new external_single_structure(
                        array(
                            'name' => new external_value(PARAM_RAW, 'function name'),
                            'version' => new external_value(PARAM_TEXT,
                                        'The version number of the component to which the function belongs')
                        ), 'functions that are available')
                    ),
                'downloadfiles'  => new external_value(PARAM_INT, '1 if users are allowed to download files, 0 if not', VALUE_OPTIONAL),
            )
        );
    }
}

/**
 * Deprecated web service related functions
 * @deprecated since Moodle 2.2 please use core_webservice_external instead
 */
class moodle_webservice_external extends external_api {

    /**
     * Returns description of method parameters
     * @deprecated since Moodle 2.2 please use core_webservice_external::get_site_info_parameters instead
     * @return external_function_parameters
     */
    public static function get_siteinfo_parameters() {
        return core_webservice_external::get_site_info_parameters();
    }

    /**
     * Return user information including profile picture + basic site information
     * Note:
     * - no capability checking because we return just known information by logged user
     * @deprecated since Moodle 2.2 please use core_webservice_external::get_site_info instead
     * @param array $serviceshortnames of service shortnames - the functions of these services will be returned
     * @return array
     */
    public function get_siteinfo($serviceshortnames = array()) {
        return core_webservice_external::get_site_info($serviceshortnames);
    }

    /**
     * Returns description of method result value
     * @deprecated since Moodle 2.2 please use core_webservice_external::get_site_info_returns instead
     * @return external_single_structure
     */
    public static function get_siteinfo_returns() {
        return core_webservice_external::get_site_info_returns();
    }
}
