<?php
/**
 * @author Denis CLAVIER <clavierd at gmail dot com>
 * Adapted from Oauth2-server-php cookbook
 * @see http://bshaffer.github.io/oauth2-server-php-docs/cookbook/
 */

// include our OAuth2 Server object
require_once __DIR__.'/server.php';

// include our LDAP object
require_once __DIR__.'/LDAP/LDAP.php';
require_once __DIR__.'/LDAP/config_ldap.php';

// Handle a request to a resource and authenticate the access token
if (!$server->verifyResourceRequest(OAuth2\Request::createFromGlobals())) {
    $server->getResponse()->send();
    die;
}

// set default error message
$resp = array("error" => "Unknown error", "message" => "An unknown error has occured, please report this bug");

// get information on user associated to the token
$info_oauth = $server->getAccessTokenData(OAuth2\Request::createFromGlobals());
$user = $info_oauth["user_id"];
$assoc_id = intval($info_oauth["assoc_id"]);

// Open a LDAP connection
$ldap = new LDAP($ldap_host, $ldap_port, $ldap_version);

// Try to get user data on the LDAP
try {
    $data = $ldap->getDataForMattermost($ldap_base_dn, $ldap_filter, $ldap_bind_dn, $ldap_bind_pass, $ldap_search_attribute, $user);

    // Here is the patch for Mattermost 4.4 and newer. Gitlab has changed the JSON output of oauth service. Many data are not used by Mattermost, but there is a stack error if we delete them. That's the reason why date and many parameters are null or empty.
    $resp = array("id" => $assoc_id,"name" => $data['cn'],"username" => $user,"state" => "active","avatar_url" => "","web_url" => "","created_at" => "0000-00-00T00:00:00.000Z","bio" => null,"location" => null,"skype" => "","linkedin" => "","twitter" => "","website_url" => "","organization" => null,"last_sign_in_at" => "0000-00-00T00:00:00.000Z","confirmed_at" => "0000-00-00T00:00:00.000Z","last_activity_on" => null,"email" => $data['mail'],"theme_id" => 1,"color_scheme_id" => 1,"projects_limit" => 100000,"current_sign_in_at" => "0000-00-00T00:00:00.000Z","identities" => array(array("provider" => "ldapmain","extern_uid" => $data['cn'])),"can_create_group" => true,"can_create_project" => true,"two_factor_enabled" => false,"external" => false,"shared_runners_minutes_limit" => null);

    // Below is the old version, still consistent with Mattermost before version 4.4
    // $resp = array("name" => $data['cn'],"username" => $user,"id" => $assoc_id,"state" => "active","email" => $data['mail']);
} catch (Exception $e) {
    $resp = array("error" => "Impossible to get data", "message" => $e->getMessage());
}

// send data or error message in JSON format
echo json_encode($resp);