package signers

import (
	"crypto/hmac"
	"crypto/sha1"
	"encoding/base64"
	"golib.gaore.com/GaoreGo/gaore-common-sdk-go/sdk/auth/credentials"
)

type AccessKeySigner struct {
	credential *credentials.AccessKeyCredential
}

func (signer *AccessKeySigner) GetAccessKeyId() (string, error) {
	return signer.credential.AccessKeyId, nil
}

func (*AccessKeySigner) GetName() string {
	return "HMAC-SHA1"
}

func (signer *AccessKeySigner) Sign(stringToSign, secretSuffix string) string {
	secret := signer.credential.AccessKeySecret + secretSuffix
	return ShaHmac1(stringToSign, secret)
}

func NewAccessKeySigner(credential *credentials.AccessKeyCredential) *AccessKeySigner {
	return &AccessKeySigner{
		credential: credential,
	}
}

func ShaHmac1(source, secret string) string {
	key := []byte(secret)
	hmac := hmac.New(sha1.New, key)
	hmac.Write([]byte(source))
	signedBytes := hmac.Sum(nil)
	signedString := base64.StdEncoding.EncodeToString(signedBytes)
	return signedString
}