// skipContentSha256Cksum returns true if caller needs to skip
// payload checksum, false if not.
func skipContentSha256Cksum(r *http.Request) bool {
	var (
		v  []string
		ok bool
	)

	if isRequestPresignedSignatureV4(r) {
		v, ok = r.Form[xhttp.AmzContentSha256]
		if !ok {
			v, ok = r.Header[xhttp.AmzContentSha256]
		}
	} else {
		v, ok = r.Header[xhttp.AmzContentSha256]
	}

	// Skip if no header was set.

	return (!strings.HasPrefix(r.Header.Get(xhttp.Authorization), signV4Algorithm) &&
		strings.HasPrefix(r.Header.Get(xhttp.Authorization), signV2Algorithm))
}

// Verify if request has AWS PreSign Version '4'.
func isRequestPresignedSignatureV4(r *http.Request) bool {
	_, ok := r.Form[xhttp.AmzCredential]
	return ok
}

// Verify request has AWS PreSign Version '2'.
func isRequestPresignedSignatureV2(r *http.Request) bool {

		}
		q := inputReq.URL.Query()
		q.Add(testCase.inputQueryKey, testCase.inputQueryValue)
		inputReq.URL.RawQuery = q.Encode()
		inputReq.ParseForm()

		actualResult := isRequestPresignedSignatureV4(inputReq)
		if testCase.expectedResult != actualResult {
			t.Errorf("Test %d: Expected the result to `%v`, but instead got `%v`", i+1, testCase.expectedResult, actualResult)
		}
	}
}

func hasMultipleAuth(r *http.Request) bool {
	authTypeCount := 0
	for _, hasValidAuth := range []func(*http.Request) bool{
		isRequestSignatureV2, isRequestPresignedSignatureV2,
		isRequestSignatureV4, isRequestPresignedSignatureV4,
		isRequestJWT, isRequestPostPolicySignatureV4,
	} {
		if hasValidAuth(r) {
			authTypeCount++
		}
	}
	return authTypeCount > 1
}