package main

import (
	"errors"
	"fmt"
	"os"

	"git.tilde.town/tildetown/town/email"
	"git.tilde.town/tildetown/town/invites"
)

const emailText = `hello!

You applied to https://tilde.town at some point and your application has been approved ^_^

Your invite code is: %s

To redeem your code, please open a terminal and run:

ssh welcome@tilde.town

You'll fill in details like your desired username and SSH public key.

If you're brand new to SSH or have never heard of it that is okay!

This page has information on what SSH is and how to use it, including how to create an ssh key pair which you'll need to access your town account: https://tilde.town/wiki/getting-started/ssh.html

If you run into confusion or problems creating a key pair on your computer, this page can generate one for you: https://tilde.town/keymachine . However you'll still need to save the generated key files to your computer in order to use them.

If you end up stuck, e-mail root@tilde.town with any questions.

See you on the server,
~vilmibm`

func loadPassword() (string, error) {
	f, err := os.Open("/town/docs/smtp.pw")
	if err != nil {
		return "", err
	}

	pw := make([]byte, 100)

	n, err := f.Read(pw)
	if err != nil {
		return "", err
	}
	if n == 0 {
		return "", errors.New("read nothing")
	}

	return string(pw[0:n]), nil
}

func sendInviteEmail(invite invites.Invite) error {
	pw, err := loadPassword()
	if err != nil {
		return fmt.Errorf("could not read password: %w", err)
	}

	body := fmt.Sprintf(emailText, invite.Code)

	mailer := email.NewExternalMailer(pw)
	return mailer.Send(
		invite.Email,
		"your tilde.town application was accepted",
		body)
}