ConsultationExtendRules.cs

        public static ConsultationUserExtendInfo GetUserExtendInfo(ConsultationSessionStateDto consultation, List<ConsultationPreviousStatesDto> previousStates)
        {
            ConsultationUserExtendInfo userExtendInfo = new ConsultationUserExtendInfo()
            {
                IsAllowed = true,
                //ExtendDuration = 5 // Minutes Duration By Default
            };

            try
            {
                // if the user has extended once before or the doctor has extended once before, then reject extend
                var consultType = consultation.Type.ToEnumOrDefault<ConsultationType>(ConsultationType.Unknown);
                var consultLastState = consultation.LastState.ToEnum<ConsultationState>();

                if (consultType == ConsultationType.CuraAnyTimeConsult ||
                    consultType == ConsultationType.BundleConsult ||
                    consultType == ConsultationType.AdhocSupportConsult ||
                    consultType == ConsultationType.AdhocConsult ||
                    consultType == ConsultationType.SupportClinicConsult ||
                    consultType == ConsultationType.TelesalesConsult ||
                    consultType == ConsultationType.Unknown)
                {
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorInvalidType;
                    return userExtendInfo;
                }

                // if in an invalid state, can't extend
                if (consultLastState != ConsultationState.SessionEndedByUser &&
                    consultLastState != ConsultationState.SessionEndedByDoctor &&
                    consultLastState != ConsultationState.SessionTimerEnded)
                {
                    // only allow followup if it hasn't been consumed before (no additional paid followups anymore)
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorInvalidState;
                    return userExtendInfo;
                }


                //if already extended by the user once before, then reject
                if (previousStates?.Count(q => q.LastState == ConsultationState.SessionExtendedForTokenByUserRequest.ToFriendlyString()) > 0)
                {
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorAlreadyExtended;
                    return userExtendInfo;
                }

                //if already extended by the doctor once before, then reject
                if (previousStates?.Count(q => q.LastState == ConsultationState.SessionExtendedForFreeByDoctorRequest.ToFriendlyString())
                    // || q.LastState == ConsultationState.SessionExtendedForTokenByDoctorRequest.ToFriendlyString()) 
                    > 0)
                {
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorAlreadyExtendedBydoctor;
                    return userExtendInfo;
                }

                // if already had a free followup, then reject extension
                if (previousStates?.Count(q => q.LastState == ConsultationState.SessionExtendedByUserFollowUpRequest.ToFriendlyString())
                > 0)
                {
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorAlreadyExtended;
                    return userExtendInfo;
                }

                // Prevent session extend on the client unless the extension was requested within 3 days of starting the consultation
                // Ensuring the entity is filled, fixing an issue where the timer ends before the doctor accepts the consultation
                var consultAcceptedEntity = consultation.PreviousStates.SafeWhere(q => q.LastState == "SessionAccepted").FirstOrDefault();
                
                if (consultAcceptedEntity == null)
                    consultAcceptedEntity = consultation.PreviousStates.LastOrDefault();

                //var consultation = Repository.GetConsultationSessionState(new ConsultationSessionState() { Id = request.Id });
                if (consultAcceptedEntity.Created <= DateTime.UtcNow.AddDays(-3))
                {
                    // TODO :: must revamp status code .. this should be 500 server error since the client has no problem
                    // making the request.. its the server that couldn't fullfill the client request so it should be 5xx error not 4xx
                    // but if you return 500, then cura apps show generic 'service is down' error message so this needs fixing in clients
                    userExtendInfo.IsAllowed = false;
                    userExtendInfo.Reason = Resources.SessionExtensionErrorPastThreeDays;
                    return userExtendInfo;

                    // TODO :: must send typed custom exceptions instead. Clients still sees them as ServiceStack.WebServiceExceptions
                    // throw new CuraBusinessException((int)HttpStatusCode.BadRequest, Resources.SessionExtensionNotAllowed);
                }
            }
            catch (Exception Ex)
            {
                ExceptionLogger.Log(Ex);
                return userExtendInfo;
            }
            return userExtendInfo;
        }