model.addUser = ( obj ) => {

    //Inicia uma transação
    const beginTransaction = ( connection ) => {
        return new Promise((resolve, reject) => {
            connection.beginTransaction((err) => {
                if ( err ) reject(err)

                resolve(connection)
            })
        })
    }

    //Adiciona o usuário, propriamente dito, no banco
    const addUser = ( user ) => ( connection ) => {

        const cpf = user.cpf
        const name = user.name
        const mail = user.mail
        const password = user.password
        const genre = user.genre

        const fields = {
            cpf: cpf,
            nome: name,
            email: mail,
            senha: password,
            sexo: genre
        }

        return new Promise((resolve, reject) => {
            connection.query('INSERT INTO usuarios SET ?', fields, (error, results, fields) => {
                if ( error ) {
                    return connection.rollback(() => {
                        reject(error)
                    })
                }

                resolve(results.insertId)
            })
        })
    }

    //Vincula o endereço informado ao último cliente cadastrado
    const addUserAddress = ( address ) => ( last_id ) => {

        const id_usuario = last_id
        const cep = address.cep
        const logradouro = address.logradouro
        const numero = address.numero
        const complemento = address.complemento
        const bairro = address.bairro
        const cidade = address.cidade
        const uf = address.uf

        return new Promise((resolve, reject) => {
            resolve(last_id)
        })
    }

    return new Promise((resolve, reject) => {
        beginTransaction(connection)
        .then(addUser(obj))
        .then(addUserAddress(connection))
        .catch(error => reject(error))
    })
}