// Copyright (c) 2022 Proton AG
//
// This file is part of Proton Mail Bridge.
//
// Proton Mail Bridge is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Proton Mail Bridge is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.

package message

import (
	"crypto/sha256"
	"encoding/hex"
)

type boundary struct {
	val string
}

func newBoundary(seed string) *boundary {
	return &boundary{val: seed}
}

func (bw *boundary) gen() string {
	hash := sha256.New()

	if _, err := hash.Write([]byte(bw.val)); err != nil {
		panic(err)
	}

	bw.val = hex.EncodeToString(hash.Sum(nil))

	return bw.val
}