public override async Task <ICollection <FilterValue> > GetAvailableValuesAsync(IEnumerable <Guid> necessaryMIATypeIds, IFilter selectAttributeFilter, IFilter filter) { IContentDirectory cd = ServiceRegistration.Get <IServerConnectionManager>().ContentDirectory; if (cd == null) { throw new NotConnectedException("The MediaLibrary is not connected"); } bool showVirtual = VirtualMediaHelper.ShowVirtualMedia(necessaryMIATypeIds); if (string.IsNullOrEmpty(CertificationHelper.DisplayMovieCertificationCountry)) { HomogenousMap valueGroups = await cd.GetValueGroupsAsync(MovieAspect.ATTR_CERTIFICATION, null, ProjectionFunction.None, necessaryMIATypeIds, filter, true, showVirtual); IList <FilterValue> result = new List <FilterValue>(valueGroups.Count); int numEmptyEntries = 0; foreach (KeyValuePair <object, object> group in valueGroups) { string certification = (string)group.Key; if (!string.IsNullOrEmpty(certification)) { CertificationMapping cert; if (CertificationMapper.TryFindMovieCertification(certification, out cert)) { result.Add(new FilterValue(cert.CertificationId, cert.Name, new RelationalFilter(MovieAspect.ATTR_CERTIFICATION, RelationalOperator.EQ, certification), null, (int)group.Value, this)); } } else { numEmptyEntries += (int)group.Value; } } if (numEmptyEntries > 0) { result.Insert(0, new FilterValue("UR", Consts.RES_VALUE_UNRATED_TITLE, new EmptyFilter(MovieAspect.ATTR_CERTIFICATION), null, numEmptyEntries, this)); } return(result); } else { IList <FilterValue> result = new List <FilterValue>(); IFilter emptyFilter = new EmptyFilter(MovieAspect.ATTR_CERTIFICATION); int numEmptyItems = await cd.CountMediaItemsAsync(necessaryMIATypeIds, BooleanCombinationFilter.CombineFilters(BooleanOperator.And, filter, emptyFilter), true, showVirtual); if (numEmptyItems > 0) { result.Add(new FilterValue("UR", Consts.RES_VALUE_UNRATED_TITLE, emptyFilter, null, numEmptyItems, this)); } List <string> usedFilters = new List <string>(); foreach (var cert in CertificationMapper.GetMovieCertificationsForCountry(CertificationHelper.DisplayMovieCertificationCountry)) { IEnumerable <CertificationMapping> certs = CertificationMapper.FindAllAllowedMovieCertifications(cert.CertificationId); if (certs.Count() > 0) { List <string> certList = new List <string>(certs.Select(c => c.CertificationId).Except(usedFilters)); usedFilters.AddRange(certList); IFilter certFilter = new InFilter(MovieAspect.ATTR_CERTIFICATION, certList); int numItems = await cd.CountMediaItemsAsync(necessaryMIATypeIds, BooleanCombinationFilter.CombineFilters(BooleanOperator.And, filter, certFilter), true, showVirtual); result.Add(new FilterValue(cert.CertificationId, cert.Name, certFilter, null, numItems, this)); } } return(result); } }