"github.com/dustin/go-humanize"
	jwtgo "github.com/golang-jwt/jwt/v4"
	jsoniter "github.com/json-iterator/go"
)

// SigningMethodHMAC - Implements the HMAC-SHA family of signing methods signing methods
// Expects key type of []byte for both signing and validation
type SigningMethodHMAC struct {
	Name       string
	Hash       crypto.Hash
	HasherPool sync.Pool
}

// Specific instances for HS256, HS384, HS512
var (

	stringToSign := alg +
		cr.seedDate.Format(iso8601Format) + "\n" +
		getScope(cr.seedDate, cr.region) + "\n" +
		cr.seedSignature + "\n" +
		emptySHA256 + "\n" +
		hashedChunk

	// Get hmac signing key.
	signingKey := getSigningKey(cr.cred.SecretKey, cr.seedDate, cr.region, serviceS3)

	// Calculate signature.
	newSignature := getSignature(signingKey, stringToSign)

	return newSignature
}

	ResponseTypesSupported           []string `json:"response_types_supported,omitempty"`
	SubjectTypesSupported            []string `json:"subject_types_supported,omitempty"`
	IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported,omitempty"`
	ScopesSupported                  []string `json:"scopes_supported,omitempty"`
	TokenEndpointAuthMethods         []string `json:"token_endpoint_auth_methods_supported,omitempty"`

	ResponseTypesSupported           []string `json:"response_types_supported,omitempty"`
	SubjectTypesSupported            []string `json:"subject_types_supported,omitempty"`
	IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported,omitempty"`
	ScopesSupported                  []string `json:"scopes_supported,omitempty"`
	TokenEndpointAuthMethods         []string `json:"token_endpoint_auth_methods_supported,omitempty"`

		return auth.Credentials{}, s3Err
	}

	r := &http.Request{Header: formValues}
	cred, _, s3Err := checkKeyValid(r, credHeader.accessKey)
	if s3Err != ErrNone {
		return cred, s3Err
	}

	// Get signing key.
	signingKey := getSigningKey(cred.SecretKey, credHeader.scope.date, credHeader.scope.region, serviceS3)

	// Get signature.
	newSignature := getSignature(signingKey, formValues.Get("Policy"))

	ResponseTypesSupported           []string `json:"response_types_supported,omitempty"`
	SubjectTypesSupported            []string `json:"subject_types_supported,omitempty"`
	IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported,omitempty"`
	ScopesSupported                  []string `json:"scopes_supported,omitempty"`
	TokenEndpointAuthMethods         []string `json:"token_endpoint_auth_methods_supported,omitempty"`

const iso8601TimeFormat = "2006-01-02T15:04:05.000Z"

// Excerpts from @lsegal - https://github.com/aws/aws-sdk-js/issues/659#issuecomment-120477258
//
//	User-Agent:
//
//	    This is ignored from signing because signing this causes problems with generating pre-signed URLs
//	    (that are executed by other agents) or when customers pass requests through proxies, which may
//	    modify the user-agent.
//
//	Authorization:
//

type SignatureDoesNotMatch struct{}

func (e SignatureDoesNotMatch) Error() string {
	return "The request signature we calculated does not match the signature you provided. Check your key and signing method."
}

// StorageFull storage ran out of space.
type StorageFull struct{}

func (e StorageFull) Error() string {
	return "Storage reached its minimum free drive threshold."
}

	c.Assert(err, nil)
	response, err = s.client.Do(request)
	c.Assert(err, nil)
	verifyError(c, response, "SignatureDoesNotMatch", "The request signature we calculated does not match the signature you provided. Check your key and signing method.", http.StatusForbidden)
}

// This tests validate if PUT handler can successfully detect SHA256 mismatch.
func (s *TestSuiteCommon) TestSHA256Mismatch(c *check) {
	// generate a random bucket name.

	},
	ErrSignatureDoesNotMatch: {
		Code:           "SignatureDoesNotMatch",
		Description:    "The request signature we calculated does not match the signature you provided. Check your key and signing method.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrMethodNotAllowed: {
		Code:           "MethodNotAllowed",
		Description:    "The specified method is not allowed against this resource.",