// Copyright 2020 Google LLC.
//
// 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 main

import (
	"bytes"
	"compress/gzip"
	"encoding/hex"
	"fmt"
	"io"
	"log"
	"os"
)

// This is equivalent to running
//
//	gzip --stdout | xxd -p | tr -d '\n'
//
// but with a platform-independent gzip encoding to provide more stable results.
func main() {
	// gzip the spec
	var buf bytes.Buffer
	zw, _ := gzip.NewWriterLevel(&buf, gzip.BestCompression)

	if _, err := io.Copy(zw, os.Stdin); err != nil {
		log.Fatal(err)
	}

	if err := zw.Close(); err != nil {
		log.Fatal(err)
	}

	// hex-encode the spec
	s := hex.EncodeToString(buf.Bytes())

	fmt.Printf("%s", s)
}
