cli.go

package main

import (
	"errors"
	"regexp"

	"github.com/manifoldco/promptui"
	"github.com/ushu/udemy-backup/client"
)

// inspired from taken verbatim from http://www.golangprograms.com/regular-expression-to-validate-email-address.html
var emailRegexp = regexp.MustCompile("(?i)^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,8}$")

// selectCourse allows to select a course among a previously-downloaded list
func selectCourse(courses []*client.Course) (*client.Course, error) {
	templates := &promptui.SelectTemplates{
		Label:    "{{ . }}?",
		Active:   "🤓 {{ .Title | cyan }} ({{ .ID | red }})",
		Inactive: "  {{ .Title | cyan }} ({{ .ID | red }})",
		Selected: "🚀 {{ .Title | red | cyan }}",
		Details: `
--------- Course ----------
{{ "Title:" | faint }}	{{ .Title }}
{{ "URL:" | faint }}	https://www.udemy.com{{ .URL }}`,
	}

	prompt := promptui.Select{
		Label:     "Select course to backup",
		Items:     courses,
		Templates: templates,
	}

	i, _, err := prompt.Run()
	if err != nil {
		return nil, err
	}
	return courses[i], nil
}

func askCredentials() (email string, password string, err error) {
	prompt := promptui.Prompt{
		Label:    "Email",
		Validate: isEmail,
	}
	email, err = prompt.Run()
	if err != nil {
		return
	} else if email == "" {
		err = errors.New("email is required")
		return
	}

	prompt = promptui.Prompt{
		Label:    "Password",
		Mask:     '•',
		Validate: notEmpty,
	}
	password, err = prompt.Run()
	if err == nil && password == "" {
		err = errors.New("password is required")
	}
	return
}

func isEmail(s string) error {
	if !emailRegexp.MatchString(s) {
		return errors.New("not a valid email")
	}
	return nil
}

func notEmpty(s string) error {
	if s == "" {
		return errors.New("cannot be empty")
	}
	return nil
}