// generates CopyObjectResponse from etag and lastModified time.
func generateCopyObjectResponse(etag string, lastModified time.Time) CopyObjectResponse {
	return CopyObjectResponse{
		ETag:         "\"" + etag + "\"",
		LastModified: amztime.ISO8601Format(lastModified.UTC()),
	}
}

// generates CopyObjectPartResponse from etag and lastModified time.

// WriteHeaders writes the response headers for conditional requests
func (oi ObjectInfo) WriteHeaders(w http.ResponseWriter, preamble, statusCode func()) {
	preamble()

	if !oi.ModTime.IsZero() {
		w.Header().Set(xhttp.LastModified, oi.ModTime.UTC().Format(http.TimeFormat))
	}

	if oi.ETag != "" {
		w.Header()[xhttp.ETag] = []string{"\"" + oi.ETag + "\""}
	}

	if oi.Expires != "" {
		w.Header().Set(xhttp.Expires, oi.Expires)
	}

	for obj := range objCh {
		if obj.Err != nil {
			log.Fatalf("Listing error: %v", obj.Err)
		}
		fmt.Printf("Key: %s\nSize: %d\nLast Modified: %s\n===\n", obj.Key, obj.Size, obj.LastModified)
	}

	for obj := range objCh {
		if obj.Err != nil {
			log.Fatalf("Listing error: %v", obj.Err)
		}
		fmt.Printf("Key: %s\nSize: %d\nLast Modified: %s\n===\n", obj.Key, obj.Size, obj.LastModified)
	}

	// set common headers
	setCommonHeaders(w)

	// Set last modified time.
	lastModified := objInfo.ModTime.UTC().Format(http.TimeFormat)
	w.Header().Set(xhttp.LastModified, lastModified)

	// Set Etag if available.
	if objInfo.ETag != "" {
		w.Header()[xhttp.ETag] = []string{"\"" + objInfo.ETag + "\""}
	}

	if objInfo.ContentType != "" {

		for object := range s3Client.ListObjects(context.Background(), bucket, opts) {
			if object.Err != nil {
				log.Println("FAILED: LIST with error:", object.Err)
				continue
			}
			if !minModTime.IsZero() && object.LastModified.Before(minModTime) {
				continue
			}
			if object.IsDeleteMarker {
				log.Println("SKIPPED: DELETE marker object:", objFullPath(object))
				continue
			}

	nextObject := func(ch <-chan minio.ObjectInfo) (ctnt minio.ObjectInfo, ok bool) {
		for {
			ctnt, ok := <-ch
			if !ok {
				return minio.ObjectInfo{}, false
			}
			if ctnt.LastModified.Before(maxObjectModTime) {
				return ctnt, ok
			}
		}
	}

	sclnt, err := buildS3Client(sourceEndpoint, sourceAccessKey, sourceSecretKey, insecure)
	if err != nil {
		log.Fatalln(err)
	}

		oi1.ModTime.Unix() > oi2.LastModified.Unix() && oi1.VersionID == nullVersionID {
		return replicateNone
	}
	sz, _ := oi1.GetActualSize()

	// needs full replication
	if oi1.ETag != oi2.ETag ||
		oi1.VersionID != oi2.VersionID ||
		sz != oi2.Size ||
		oi1.DeleteMarker != oi2.IsDeleteMarker ||
		oi1.ModTime.Unix() != oi2.LastModified.Unix() {
		return replicateAll
	}

		xhttp.ServerInfo,
		xhttp.Connection,
		xhttp.AcceptRanges,
		xhttp.ContentRange,
		xhttp.ContentEncoding,
		xhttp.ContentLength,
		xhttp.ContentType,
		xhttp.ContentDisposition,
		xhttp.LastModified,
		xhttp.ContentLanguage,
		xhttp.CacheControl,
		xhttp.RetryAfter,
		xhttp.AmzBucketRegion,
		xhttp.Expires,
		"X-Amz*",
		"x-amz*",
		"*",
	}
	opts := cors.Options{

	// Headers to be set of object content is not going to be written to the client.
	writeHeaders := func() {
		// set common headers
		setCommonHeaders(w)

		// set object-related metadata headers
		w.Header().Set(xhttp.LastModified, objInfo.ModTime.UTC().Format(http.TimeFormat))

		if objInfo.ETag != "" {
			w.Header()[xhttp.ETag] = []string{"\"" + objInfo.ETag + "\""}
		}
	}