const ldap = require('ldapjs');
const config = global.config;

let client;

const createClient = () => {
    client = ldap.createClient({
        url: config.ldap.url,
        tlsOptions: {
            rejectUnauthorized: false
        },
        reconnect: true
    });

    return client;
};

const searchUser = (userName) => {
    return new Promise((resolve, reject) => {
        const searchPath = config.ldap.dcs.map(dc => {
            return `dc=${dc}`;
        }).join(',');

        client.search(searchPath, {
            scope: 'sub',
            filter: `(&(objectclass=person)(sAMAccountName=${userName}))`
        }, (error, res) => {
            res.on('searchEntry', function (entry) {
                resolve(entry.object);
            });
            res.on('error', function (e) {
                console.log(e);
                reject(e.message);
            });
        });
    });
};

const checkUser = (userName, password) => {
    if (!config.ldap) {
        throw new Error('缺少ldap配置');
    }

    return new Promise((resolve, reject) => {
        try {
            if (!client) {
                client = createClient();
            }

            const bindPath = config.ldap.dcs.join('.');

            client.bind(`${userName}@${bindPath}`, password, async (err) => {
                if (err) {
                    return resolve(void 0);
                }
                try {
                    const user = await searchUser(userName);

                    resolve(user);
                    client.unbind();
                } catch (error) {
                    reject(error);
                }
            });
        } catch (error) {
            reject(error);
        }
    });
};

module.exports = {
    checkUser
};