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// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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 safeguardsecret - is an example of a D-TA plugin
*/
package safeguardsecret

import (
	"github.com/apache/incubator-milagro-dta/libs/crypto"
	"github.com/apache/incubator-milagro-dta/libs/cryptowallet"
	"github.com/apache/incubator-milagro-dta/libs/documents"
	"github.com/apache/incubator-milagro-dta/pkg/api"
	"github.com/apache/incubator-milagro-dta/pkg/defaultservice"
)

//Constants describe plugin and its creator
var (
	extensionVendor = "Milagro"
	pluginName      = "safeguardsecret"
)

// Service implements Safeguard secret plugin service
type Service struct {
	defaultservice.Service
}

//NewService returns a new Safeguard secret implementation of Service
func NewService() *Service {
	return &Service{}
}

// Name of the plugin
func (s *Service) Name() string {
	return pluginName
}

// Vendor of the plugin
func (s *Service) Vendor() string {
	return extensionVendor
}

// PrepareOrderResponse gets the updated order and returns the commitment and extension
func (s *Service) PrepareOrderResponse(orderPart2 *documents.OrderDoc, reqExtension, fulfillExtension map[string]string) (commitment string, extension map[string]string, err error) {
	finalPublicKey := orderPart2.OrderPart2.CommitmentPublicKey
	c, v, t, err := crypto.Secp256k1Encrypt(reqExtension["plainText"], finalPublicKey)

	return finalPublicKey, map[string]string{"cypherText": c, "v": v, "t": t}, nil
}

// ProduceFinalSecret -
func (s *Service) ProduceFinalSecret(seed, sikeSK []byte, order, orderPart4 *documents.OrderDoc, req *api.OrderSecretRequest, fulfillSecretRespomse *api.FulfillOrderSecretResponse) (secret, commitment string, extension map[string]string, err error) {
	finalPrivateKey := orderPart4.OrderDocument.OrderPart4.Secret
	//Derive the Public key from the supplied Private Key
	finalPublicKey, _, err := cryptowallet.PublicKeyFromPrivate(finalPrivateKey)
	if err != nil {
		return "", "", nil, err
	}

	plainText, err := crypto.Secp256k1Decrypt(req.Extension["cypherText"], req.Extension["v"], req.Extension["t"], finalPrivateKey)
	if err != nil {
		return "", "", nil, err
	}

	return finalPrivateKey, finalPublicKey, map[string]string{"plainText": plainText}, nil
}