package jwt

// Validation provides a backwards compatible error definition
// from `jwt-go` to `go-jose`.
// The sourcecode was taken from https://github.com/dgrijalva/jwt-go/blob/master/errors.go
//
// > The errors that might occur when parsing and validating a token
const (
	ValidationErrorMalformed        uint32 = 1 << iota // Token is malformed
	ValidationErrorUnverifiable                        // Token could not be verified because of signing problems
	ValidationErrorSignatureInvalid                    // Signature validation failed

	// Standard Claim validation errors
	ValidationErrorAudience      // AUD validation failed
	ValidationErrorExpired       // EXP validation failed
	ValidationErrorIssuedAt      // IAT validation failed
	ValidationErrorIssuer        // ISS validation failed
	ValidationErrorNotValidYet   // NBF validation failed
	ValidationErrorId            // JTI validation failed
	ValidationErrorClaimsInvalid // Generic claims validation error
)

// The error from Parse if token is not valid
type ValidationError struct {
	Inner  error  // stores the error returned by external dependencies, i.e.: KeyFunc
	Errors uint32 // bitfield.  see ValidationError... constants
	text   string // errors that do not have a valid error just have text
}

// Validation error is an error type
func (e ValidationError) Error() string {
	if e.Inner != nil {
		return e.Inner.Error()
	} else if e.text != "" {
		return e.text
	} else {
		return "token is invalid"
	}
}

// No errors
func (e *ValidationError) valid() bool {
	return e.Errors == 0
}

func (e *ValidationError) Has(verr uint32) bool {
	return (e.Errors & verr) != 0
}