package tool

import (
    "crypto"
    "crypto/ecdsa"
    "crypto/elliptic"
    "crypto/rand"
    "github.com/0xJacky/Nginx-UI/settings"
    "github.com/go-acme/lego/v4/certcrypto"
    "github.com/go-acme/lego/v4/certificate"
    "github.com/go-acme/lego/v4/challenge/http01"
    "github.com/go-acme/lego/v4/lego"
    "github.com/go-acme/lego/v4/registration"
    "io/ioutil"
    "log"
    "os"
    "path/filepath"
)

// MyUser You'll need a user or account type that implements acme.User
type MyUser struct {
    Email        string
    Registration *registration.Resource
    key          crypto.PrivateKey
}

func (u *MyUser) GetEmail() string {
    return u.Email
}
func (u MyUser) GetRegistration() *registration.Resource {
    return u.Registration
}
func (u *MyUser) GetPrivateKey() crypto.PrivateKey {
    return u.key
}

func IssueCert(domain string) error {
    // Create a user. New accounts need an email and private key to start.
    privateKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
    if err != nil {
        log.Fatal(err)
    }

    myUser := MyUser{
        Email: settings.ServerSettings.Email,
        key:   privateKey,
    }

    config := lego.NewConfig(&myUser)

    //config.CADirURL = "https://acme-staging-v02.api.letsencrypt.org/directory"
    config.Certificate.KeyType = certcrypto.RSA2048

    // A client facilitates communication with the CA server.
    client, err := lego.NewClient(config)
    if err != nil {
        log.Println(err)
        return err
    }

    err = client.Challenge.SetHTTP01Provider(
        http01.NewProviderServer("",
            settings.ServerSettings.HTTPChallengePort,
        ),
    )
    if err != nil {
        log.Println(err)
        return err
    }

    // New users will need to register
    reg, err := client.Registration.Register(registration.RegisterOptions{TermsOfServiceAgreed: true})
    if err != nil {
        log.Println(err)
        return err
    }
    myUser.Registration = reg

    request := certificate.ObtainRequest{
        Domains: []string{domain},
        Bundle:  true,
    }
    certificates, err := client.Certificate.Obtain(request)
    if err != nil {
        log.Println(err)
        return err
    }
    saveDir := GetNginxConfPath("ssl/" + domain)
    if _, err := os.Stat(saveDir); os.IsNotExist(err) {
        err = os.Mkdir(saveDir, 0755)
        if err != nil {
            log.Println("fail to create", saveDir)
            return err
        }
    }

    // Each certificate comes back with the cert bytes, the bytes of the client's
    // private key, and a certificate URL. SAVE THESE TO DISK.
    err = ioutil.WriteFile(filepath.Join(saveDir, "fullchain.cer"),
        certificates.Certificate, 0644)
    if err != nil {
        log.Println(err)
        return err
    }
    err = ioutil.WriteFile(filepath.Join(saveDir, domain + ".key"),
        certificates.PrivateKey, 0644)
    if err != nil {
        log.Println(err)
        return err
    }

    return nil
}