Elep

var metaUser = document.querySelector('meta[name="user"]');

const authenticate = function(){
    return new Promise(async function(resolve, reject) {
        var user = metaUser.getAttribute('value');
        if(user) resolve(user);
        else {
            doGet('/api/user/register')
            .then(response => {
                vexInstance = vex.open({
                    unsafeContent: response,
                    showCloseButton: false
                });

document.querySelector('.vex').addEventListener('click', function(e){
                    if(e.target.matches('.x-close') || e.target.matches('.vex-closing')){
                        vex.close(vexInstance);
                        reject("closed");
                    }
                });

document.addEventListener('submit', function(e){
                    const submitButton = document.querySelector('.login-btn');
                    const hold = submitButton.innerHTML;
                    submitButton.innerHTML = '<i class="fa fa-spinner fa-spin"></i>';
                    submitButton.setAttribute('disabled', 'disabled');
                    postForm(e).then(response => {
                        load && (load.style.display = 'none');
                        submitButton.removeAttribute('disabled');
                        submitButton.innerHTML = hold;
                        const {message, status} = response.payload;
                        if(status === 'failed'){
                            document.querySelectorAll('.form-group .error').forEach(errorInput => {
                                errorInput.innerHTML = "";
                            })
                            Object.keys(message).forEach(key => document.getElementById(key).innerHTML = message[key]);
                        }else {
                            vex.close(vexInstance);
                            metaUser.setAttribute('value', response.payload.user);
                            resolve(response);
                        }
                    });
                });
            });
        }
    });
}