'use strict';

exports = module.exports = {
    start: start,
    stop: stop
};

var assert = require('assert'),
    config = require('./config.js'),
    debug = require('debug')('box:ldap'),
    user = require('./user.js'),
    UserError = user.UserError,
    ldap = require('ldapjs');

var gServer = null;

var NOOP = function () {};

var gLogger = {
    trace: NOOP,
    debug: NOOP,
    info: debug,
    warn: debug,
    error: console.error,
    fatal: console.error
};

var GROUP_USERS_DN = 'cn=users,ou=groups,dc=cloudron';
var GROUP_ADMINS_DN = 'cn=admins,ou=groups,dc=cloudron';

function start(callback) {
    assert.strictEqual(typeof callback, 'function');

    gServer = ldap.createServer({ log: gLogger });

    gServer.search('ou=users,dc=cloudron', function (req, res, next) {
        debug('ldap user search: dn %s, scope %s, filter %s', req.dn.toString(), req.scope, req.filter.toString());

        user.list(function (error, result){
            if (error) return next(new ldap.OperationsError(error.toString()));

            // send user objects
            result.forEach(function (entry) {
                var dn = ldap.parseDN('cn=' + entry.id + ',ou=users,dc=cloudron');

                var groups = [ GROUP_USERS_DN ];
                if (entry.admin) groups.push(GROUP_ADMINS_DN);

                var tmp = {
                    dn: dn.toString(),
                    attributes: {
                        objectclass: ['user'],
                        objectcategory: 'person',
                        cn: entry.id,
                        uid: entry.id,
                        mail: entry.email,
                        displayname: entry.username,
                        username: entry.username,
                        samaccountname: entry.username,      // to support ActiveDirectory clients
                        memberof: groups
                    }
                };

                if ((req.dn.equals(dn) || req.dn.parentOf(dn)) && req.filter.matches(tmp.attributes)) {
                    res.send(tmp);
                }
            });

            res.end();
        });
    });

    gServer.search('ou=groups,dc=cloudron', function (req, res, next) {
        debug('ldap group search: dn %s, scope %s, filter %s', req.dn.toString(), req.scope, req.filter.toString());

        user.list(function (error, result){
            if (error) return next(new ldap.OperationsError(error.toString()));

            var groups = [{
                name: 'users',
                admin: false
            }, {
                name: 'admins',
                admin: true
            }];

            groups.forEach(function (group) {
                var dn = ldap.parseDN('cn=' + group.name + ',ou=groups,dc=cloudron');
                var members = group.admin ? result.filter(function (entry) { return entry.admin; }) : result;

                var tmp = {
                    dn: dn.toString(),
                    attributes: {
                        objectclass: ['group'],
                        cn: group.name,
                        memberuid: members.map(function(entry) { return entry.id; })
                    }
                };

                if ((req.dn.equals(dn) || req.dn.parentOf(dn)) && req.filter.matches(tmp.attributes)) {
                    res.send(tmp);
                }
            });

            res.end();
        });
    });

    gServer.bind('ou=apps,dc=cloudron', function(req, res, next) {
        // TODO: validate password
        debug('ldap application bind: %s', req.dn.toString());
        res.end();
    });

    gServer.bind('ou=users,dc=cloudron', function(req, res, next) {
        debug('ldap user bind: %s', req.dn.toString());

        if (!req.dn.rdns[0].cn) return next(new ldap.NoSuchObjectError(req.dn.toString()));

        user.verify(req.dn.rdns[0].cn, req.credentials || '', function (error, result) {
            if (error && error.reason === UserError.NOT_FOUND) return next(new ldap.NoSuchObjectError(req.dn.toString()));
            if (error && error.reason === UserError.WRONG_PASSWORD) return next(new ldap.InvalidCredentialsError(req.dn.toString()));
            if (error) return next(new ldap.OperationsError(error));

            res.end();
        });
    });

    gServer.listen(config.get('ldapPort'), callback);
}

function stop(callback) {
    assert.strictEqual(typeof callback, 'function');

    gServer.close();

    callback();
}