/*
Copyright 2021-2022 CAcert Inc.
SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package signing

import (
	"crypto/x509"
	"crypto/x509/pkix"
	"fmt"
	"time"
)

type X509Signing struct {
	signer Signer
	repo   Repository
}

func NewX509Signing(signer Signer, repo Repository) *X509Signing {
	return &X509Signing{signer: signer, repo: repo}
}

type RequestSignature struct {
	rawCSRData         []byte
	subjectCommonName  string
	emails             []string
	dnsNames           []string
	duration           time.Duration
	signatureAlgorithm x509.SignatureAlgorithm
}

func NewRequestSignature(
	csrBytes []byte,
	cn string,
	emails, dnsNames []string,
	duration time.Duration,
	signatureAlgorithm x509.SignatureAlgorithm,
) *RequestSignature {
	return &RequestSignature{
		rawCSRData:         csrBytes,
		subjectCommonName:  cn,
		emails:             emails,
		dnsNames:           dnsNames,
		duration:           duration,
		signatureAlgorithm: signatureAlgorithm,
	}
}

type CertificateSigned struct {
	certificate *x509.Certificate
}

func (c CertificateSigned) Certificate() *x509.Certificate {
	return c.certificate
}

func (x *X509Signing) Sign(signingRequest *RequestSignature) (*CertificateSigned, error) {
	// validate request content
	csr, err := x509.ParseCertificateRequest(signingRequest.rawCSRData)
	if err != nil {
		return nil, fmt.Errorf("could not parse CSR data: %w", err)
	}

	certificateFromSigner, err := x.signer.SignCertificate(
		NewSignerRequest(
			csr,
			pkix.Name{CommonName: signingRequest.subjectCommonName},
			signingRequest.emails,
			signingRequest.dnsNames,
			signingRequest.duration,
			signingRequest.signatureAlgorithm,
		),
	)
	if err != nil {
		return nil, fmt.Errorf("could not sign certificate: %w", err)
	}

	err = x.repo.StoreCertificate(certificateFromSigner.Certificate)
	if err != nil {
		return nil, fmt.Errorf("could not store certificate: %w", err)
	}

	return &CertificateSigned{certificate: certificateFromSigner.Certificate}, nil
}