/// <inheritdoc cref="ITrainingSessionService.GetOrganismsAsync(GetOrganismsRequest)"/>
        public async Task <GetOrganismsResponse> GetOrganismsAsync(GetOrganismsRequest getOrganismsRequest)
        {
            string          message = "Successfully fetched all requested organisms.";
            TrainingSession trainingSession;

            if (getOrganismsRequest.Amount < 1)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Amount cannot be smaller than 1."));
            }
            if ((trainingSession = await EntityRepository.FindSingleOrDefaultAsync(ts => ts.Id.Equals(getOrganismsRequest.TrainingSessionId))) == default)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Training session does not exist."));
            }
            if (!trainingSession.TrainingRoom.IsUserAuthorized(getOrganismsRequest.UserId) || trainingSession.UserId != getOrganismsRequest.UserId)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "User is not authorized."));
            }
            if (trainingSession.EndedTimestamp != default)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Training session has ended and can not be used any more."));
            }
            TrainingRoomSettings trainingRoomSettings = trainingSession.TrainingRoom.TrainingRoomSettings;

            // if the list is empty then get new ones from the training room
            if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.IsEvaluated) == 0)
            {
                if (trainingSession.TrainingRoom.Generation == 0)
                {
                    for (int i = 0; i < trainingRoomSettings.OrganismCount; i++)
                    {
                        Organism organism = new Organism(trainingRoomSettings, trainingSession.TrainingRoom.GetInnovationNumber)
                        {
                            IsLeased = true
                        };
                        trainingSession.TrainingRoom.AddOrganism(organism);
                        trainingSession.LeasedOrganisms.Add(new LeasedOrganism(organism, trainingSession.Id));
                    }
                    trainingSession.TrainingRoom.IncreaseNodeIdTo(trainingRoomSettings.InputCount + trainingRoomSettings.OutputCount);
                    message = $"First generation; generated {trainingSession.TrainingRoom.TrainingRoomSettings.OrganismCount} organisms.";
                    await _trainingSessionRepository.InsertFirstGenerationAsync(trainingSession);
                }
                else
                {
                    trainingSession.LeasedOrganisms.AddRange(GetNewLeasedOrganisms(getOrganismsRequest.Amount));
                    message = "Start of new generation.";
                    await _trainingSessionRepository.InsertLeasedOrganismsAsync(trainingSession);
                }
            }
            else if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.IsEvaluated) < getOrganismsRequest.Amount)
            {
                int take = getOrganismsRequest.Amount - trainingSession.LeasedOrganisms.Count(o => !o.Organism.IsEvaluated);
                List <LeasedOrganism> newLeasedOrganisms = GetNewLeasedOrganisms(take);
                trainingSession.LeasedOrganisms.AddRange(newLeasedOrganisms);
                await _trainingSessionRepository.SaveChangesAsync();
            }

            if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.IsEvaluated) < getOrganismsRequest.Amount && getOrganismsRequest.Amount < trainingRoomSettings.OrganismCount)
            {
                message = "The requested amount of organisms are not all available. The training room is close to a new generation.";
            }

            List <OrganismDto> organismDtos = trainingSession.LeasedOrganisms
                                              .Where(lo => !lo.Organism.IsEvaluated)
                                              .Take(getOrganismsRequest.Amount)
                                              .Select(lo =>
            {
                OrganismDto organismDto = Mapper.Map <OrganismDto>(lo.Organism);
                // Because the input and output nodes are set using a Many To Many relation the nodes are converted separately.
                organismDto.InputNodes  = lo.Organism.Inputs.Select(input => Mapper.Map <NodeDto>(input.InputNode)).ToList();
                organismDto.OutputNodes = lo.Organism.Outputs.Select(input => Mapper.Map <NodeDto>(input.OutputNode)).ToList();
                return(organismDto);
            }).ToList();

            return(new GetOrganismsResponse(getOrganismsRequest.Id, organismDtos, message, organismDtos.Any()));

            List <LeasedOrganism> GetNewLeasedOrganisms(int take)
            {
                return(trainingSession.TrainingRoom.Species
                       .SelectMany(sp => sp.Organisms)
                       .Where(lo => !lo.IsLeased)
                       .Take(take).Select(o =>
                {
                    o.IsLeased = true;
                    return new LeasedOrganism(o, trainingSession.Id);
                }).ToList());
            }
        }
        /// <inheritdoc cref="ITrainingRoomService.GetOrganismsAsync(GetOrganismsRequest)"/>
        public async Task <GetOrganismsResponse> GetOrganismsAsync(GetOrganismsRequest getOrganismsRequest)
        {
            string          message = "Successfully fetched all requested organisms.";
            TrainingSession trainingSession;

            if (getOrganismsRequest.TrainingSessionId.Equals(Guid.Empty))
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Training room id cannot be an empty guid."));
            }
            if (getOrganismsRequest.Amount < 1)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Amount cannot be smaller than 1."));
            }
            if ((trainingSession = await _trainingSessionRepository.FindSingleOrDefaultAsync(ts => ts.Id.Equals(getOrganismsRequest.TrainingSessionId))) == default)
            {
                return(new GetOrganismsResponse(getOrganismsRequest.Id, new List <OrganismDto>(), "Training session does not exist."));
            }

            // if the list is empty then get new ones from the training room
            if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.Evaluated) == 0)
            {
                if (trainingSession.TrainingRoom.Generation == 0)
                {
                    TrainingRoomSettings trainingRoomSettings = trainingSession.TrainingRoom.TrainingRoomSettings;
                    for (int i = 0; i < trainingRoomSettings.OrganismCount; i++)
                    {
                        Organism organism = new Organism(trainingSession.TrainingRoom.Generation, trainingRoomSettings)
                        {
                            Leased = true
                        };
                        trainingSession.TrainingRoom.AddOrganism(organism);
                        trainingSession.LeasedOrganisms.Add(new LeasedOrganism(organism));
                    }
                    trainingSession.TrainingRoom.IncreaseNodeIdTo(trainingRoomSettings.InputCount + trainingRoomSettings.OutputCount);
                    message = $"First generation; generated {trainingSession.TrainingRoom.TrainingRoomSettings.OrganismCount} organisms.";
                }
                else
                {
                    trainingSession.LeasedOrganisms.AddRange(GetNewLeasedOrganisms(getOrganismsRequest.Amount));
                    message = "Start of new generation.";
                }
            }
            else if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.Evaluated) < getOrganismsRequest.Amount)
            {
                int take = getOrganismsRequest.Amount - trainingSession.LeasedOrganisms.Count(o => !o.Organism.Evaluated);
                List <LeasedOrganism> newLeasedOrganisms = GetNewLeasedOrganisms(take);
                trainingSession.LeasedOrganisms.AddRange(newLeasedOrganisms);
            }

            if (trainingSession.LeasedOrganisms.Count(o => !o.Organism.Evaluated) < getOrganismsRequest.Amount)
            {
                message = "The requested amount of organisms are not all available. The training room is probably close to a new generation or is waiting on other training sessions to complete.";
            }

            await _trainingSessionRepository.UpdateAsync(trainingSession);

            List <OrganismDto> organismDtos = trainingSession.LeasedOrganisms
                                              .Where(lo => !lo.Organism.Evaluated)
                                              .Take(getOrganismsRequest.Amount)
                                              .Select(lo =>
            {
                OrganismDto organismDto = EntityToDtoConverter.Convert <OrganismDto, Organism>(lo.Organism);
                // Because the input and output nodes are set using a Many To Many relation the nodes are converted separately.
                organismDto.InputNodes  = lo.Organism.Inputs.Select(input => EntityToDtoConverter.Convert <NodeDto, InputNode>(input.InputNode)).ToList();
                organismDto.OutputNodes = lo.Organism.Outputs.Select(input => EntityToDtoConverter.Convert <NodeDto, OutputNode>(input.OutputNode)).ToList();
                return(organismDto);
            }).ToList();

            return(new GetOrganismsResponse(getOrganismsRequest.Id, organismDtos, message, organismDtos.Any()));

            List <LeasedOrganism> GetNewLeasedOrganisms(int take)
            {
                return(trainingSession.TrainingRoom.Species.SelectMany(sp => sp.Organisms).Where(lo => !lo.Leased)
                       .Take(take).Select(o =>
                {
                    o.Leased = true;
                    return new LeasedOrganism(o);
                }).ToList());
            }
        }