package utils

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"crypto/x509/pkix"
	"fmt"
	"math/big"
	"os"
	"scm/model"
	"time"

	"github.com/youmark/pkcs8"
)

func CreateRootKeyCertificate(data model.CreateRootCertRequest) error {
	privkey, err := rsa.GenerateKey(rand.Reader, 4096)
	if err != nil {
		return err
	}

	serialNumber, err := rand.Int(rand.Reader, new(big.Int).Lsh(big.NewInt(1), 128))
	if err != nil {
		return err
	}

	template := x509.Certificate{
		SerialNumber: serialNumber,
		Subject: pkix.Name{
			CommonName:         data.CommonName,
			OrganizationalUnit: data.OrganizationalUnit,
			Organization:       data.Organization,
			Country:            data.Country,
			Locality:           data.Locality,
			Province:           data.Province,
			StreetAddress:      data.StreetAddress,
			PostalCode:         data.PostalCode,
			SerialNumber:       serialNumber.String(),
		},
		NotBefore: time.Now(),
		NotAfter:  time.Now().AddDate(data.ValidityYears, 0, 0),
		KeyUsage:  x509.KeyUsageCertSign | x509.KeyUsageCRLSign | x509.KeyUsageDigitalSignature,
		ExtKeyUsage: []x509.ExtKeyUsage{
			x509.ExtKeyUsageServerAuth,
			x509.ExtKeyUsageClientAuth,
		},
		BasicConstraintsValid: true,
		IsCA:                  true,
	}

	cert, err := x509.CreateCertificate(rand.Reader, &template, &template, &privkey.PublicKey, privkey)
	if err != nil {
		return err
	}

	encryptedKey, err := pkcs8.ConvertPrivateKeyToPKCS8(
		privkey,
		[]byte(data.KeyPassword),
	)
	if err != nil {
		return err
	}

	err = CheckExistsOrCreateDir("root")
	if err != nil {
		return err
	}

	err = SavePEMFile(fmt.Sprintf(
		"%s/%s",
		os.Getenv("CERTS_PATH"),
		"root/root.crt",
	),
		"CERTIFICATE",
		cert,
	)
	if err != nil {
		return err
	}

	err = SavePEMFile(fmt.Sprintf(
		"%s/%s",
		os.Getenv("CERTS_PATH"),
		"root/root.key",
	), "ENCRYPTED PRIVATE KEY", encryptedKey)
	if err != nil {
		return err
	}
	// Implementation of CreateRootCertificate function
	return nil
}