feat: v2 api add way to list authentication factors (#9065)

# Which Problems Are Solved

The v2 api currently has no endpoint the get all second factors of a
user.

# How the Problems Are Solved

Our v1 api has the ListHumanAuthFactors which got added to the v2 api
under the User resource.

# Additional Changes

# Additional Context

Closes #8833

---------

Co-authored-by: Stefan Benz <46600784+stebenz@users.noreply.github.com>

internal/api/grpc/object/v2/converter.go

@@ -9,6 +9,7 @@ import (
 	"github.com/zitadel/zitadel/internal/domain"
 	"github.com/zitadel/zitadel/internal/query"
 	"github.com/zitadel/zitadel/pkg/grpc/object/v2"
+	user_pb "github.com/zitadel/zitadel/pkg/grpc/user/v2"
 )
 
 func DomainToDetailsPb(objectDetail *domain.ObjectDetails) *object.Details {
@@ -70,3 +71,105 @@ func TextMethodToQuery(method object.TextQueryMethod) query.TextComparison {
 		return -1
 	}
 }
+
+func AuthMethodsToPb(mfas *query.AuthMethods) []*user_pb.AuthFactor {
+	factors := make([]*user_pb.AuthFactor, len(mfas.AuthMethods))
+	for i, mfa := range mfas.AuthMethods {
+		factors[i] = AuthMethodToPb(mfa)
+	}
+	return factors
+}
+
+func AuthMethodToPb(mfa *query.AuthMethod) *user_pb.AuthFactor {
+	factor := &user_pb.AuthFactor{
+		State: MFAStateToPb(mfa.State),
+	}
+	switch mfa.Type {
+	case domain.UserAuthMethodTypeTOTP:
+		factor.Type = &user_pb.AuthFactor_Otp{
+			Otp: &user_pb.AuthFactorOTP{},
+		}
+	case domain.UserAuthMethodTypeU2F:
+		factor.Type = &user_pb.AuthFactor_U2F{
+			U2F: &user_pb.AuthFactorU2F{
+				Id:   mfa.TokenID,
+				Name: mfa.Name,
+			},
+		}
+	case domain.UserAuthMethodTypeOTPSMS:
+		factor.Type = &user_pb.AuthFactor_OtpSms{
+			OtpSms: &user_pb.AuthFactorOTPSMS{},
+		}
+	case domain.UserAuthMethodTypeOTPEmail:
+		factor.Type = &user_pb.AuthFactor_OtpEmail{
+			OtpEmail: &user_pb.AuthFactorOTPEmail{},
+		}
+	case domain.UserAuthMethodTypeUnspecified:
+	case domain.UserAuthMethodTypePasswordless:
+	case domain.UserAuthMethodTypePassword:
+	case domain.UserAuthMethodTypeIDP:
+	case domain.UserAuthMethodTypeOTP:
+	case domain.UserAuthMethodTypePrivateKey:
+	}
+	return factor
+}
+
+func AuthFactorsToPb(authFactors []user_pb.AuthFactors) []domain.UserAuthMethodType {
+	factors := make([]domain.UserAuthMethodType, len(authFactors))
+	for i, authFactor := range authFactors {
+		factors[i] = AuthFactorToPb(authFactor)
+	}
+	return factors
+}
+
+func AuthFactorToPb(authFactor user_pb.AuthFactors) domain.UserAuthMethodType {
+	switch authFactor {
+	case user_pb.AuthFactors_OTP:
+		return domain.UserAuthMethodTypeTOTP
+	case user_pb.AuthFactors_OTP_SMS:
+		return domain.UserAuthMethodTypeOTPSMS
+	case user_pb.AuthFactors_OTP_EMAIL:
+		return domain.UserAuthMethodTypeOTPEmail
+	case user_pb.AuthFactors_U2F:
+		return domain.UserAuthMethodTypeU2F
+	default:
+		return domain.UserAuthMethodTypeUnspecified
+	}
+}
+
+func AuthFactorStatesToPb(authFactorStates []user_pb.AuthFactorState) []domain.MFAState {
+	factorStates := make([]domain.MFAState, len(authFactorStates))
+	for i, authFactorState := range authFactorStates {
+		factorStates[i] = AuthFactorStateToPb(authFactorState)
+	}
+	return factorStates
+}
+
+func AuthFactorStateToPb(authFactorState user_pb.AuthFactorState) domain.MFAState {
+	switch authFactorState {
+	case user_pb.AuthFactorState_AUTH_FACTOR_STATE_UNSPECIFIED:
+		return domain.MFAStateUnspecified
+	case user_pb.AuthFactorState_AUTH_FACTOR_STATE_NOT_READY:
+		return domain.MFAStateNotReady
+	case user_pb.AuthFactorState_AUTH_FACTOR_STATE_READY:
+		return domain.MFAStateReady
+	case user_pb.AuthFactorState_AUTH_FACTOR_STATE_REMOVED:
+		return domain.MFAStateRemoved
+	default:
+		return domain.MFAStateUnspecified
+	}
+}
+
+func MFAStateToPb(state domain.MFAState) user_pb.AuthFactorState {
+	switch state {
+	case domain.MFAStateNotReady:
+		return user_pb.AuthFactorState_AUTH_FACTOR_STATE_NOT_READY
+	case domain.MFAStateReady:
+		return user_pb.AuthFactorState_AUTH_FACTOR_STATE_READY
+	case domain.MFAStateUnspecified, domain.MFAStateRemoved:
+		// Handle all remaining cases so the linter succeeds
+		return user_pb.AuthFactorState_AUTH_FACTOR_STATE_UNSPECIFIED
+	default:
+		return user_pb.AuthFactorState_AUTH_FACTOR_STATE_UNSPECIFIED
+	}
+}