package email

import (
	"bytes"
	"text/template"
	"time"

	"code.chrissexton.org/cws/happy/user"

	mail "github.com/xhit/go-simple-mail"
)

var NoReply = `noreply@chrissexton.org`
var NewUserSubject = `Welcome to Happy`
var NewUserBody = `Welcome, {{.String}},

You may activate your new account with this link:
{{.BaseURL}}/user/{{.String}}/{{.Verification}}

Be sure to keep this URL and use it to log in to any devices. If you should lose it, just ask for a new one via the website.
You should always see {{.String}} at the bottom of the screen if you are logged in to this account.`

var newUserTpl = template.Must(template.New("NewUser").Parse(NewUserBody))

type EMailClient struct {
	*mail.SMTPServer
}

func New(addr string, port int, user, pass string) *EMailClient {
	m := EMailClient{
		mail.NewSMTPClient(),
	}
	m.Host = addr
	m.Port = port
	m.Username = user
	m.Password = pass
	m.Encryption = mail.EncryptionTLS

	m.KeepAlive = false
	m.ConnectTimeout = 10 * time.Second
	m.SendTimeout = 10 * time.Second

	return &m
}

func (e *EMailClient) Send(from, to, subject, body string, isHTML bool) error {
	client, err := e.Connect()
	if err != nil {
		return err
	}
	msg := mail.NewMSG()

	if isHTML {
		msg.SetBody(mail.TextHTML, body)
	} else {
		msg.SetBody(mail.TextPlain, body)
	}

	msg.SetFrom(from).
		AddTo(to).
		SetSubject(subject)

	err = msg.Send(client)
	return err
}

func (e *EMailClient) SendNewUserMail(to string, u user.User, url string) error {
	w := bytes.NewBufferString("")
	tplArgs := struct {
		user.User
		BaseURL string
	}{u, url}
	newUserTpl.Execute(w, tplArgs)
	return e.Send(NoReply, to, NewUserSubject, w.String(), false)
}