public override IEnumerable <System.Linq.Expressions.MemberBinding> InnerSelectBindings(Type selectType, System.Linq.Expressions.ParameterExpression sourceTypeParameter)
{
//the earliest encounter date that satisfies the query critieria
ParameterExpression pe_sourceQueryType = sourceTypeParameter;
Expression encountersProp = Expressions.AsQueryable(Expression.Property(pe_sourceQueryType, "Encounters"));
ParameterExpression pe_encountersQueryType = Expression.Parameter(typeof(PCORIQueryBuilder.Model.Encounter), "enc");
Expression admittedOnSelector = Expression.Property(pe_encountersQueryType, "AdmittedOn");
BinaryExpression be_encounterPatient = Expression.Equal(Expression.Property(pe_sourceQueryType, "ID"), Expression.Property(pe_encountersQueryType, "PatientID"));
BinaryExpression predicate = be_encounterPatient;
if (Criteria.Any(c => c.Terms.Any(t => t.Type == ModelTermsFactory.ObservationPeriodID)))
{
var observationPeriodCriteria = Criteria.SelectMany(c => c.Terms.Where(t => t.Type == ModelTermsFactory.ObservationPeriodID));
foreach (var obpTerm in observationPeriodCriteria)
{
DateTime dateValue;
var range = AdapterHelpers.ParseDateRangeValues(obpTerm);
if (range.StartDate.HasValue)
{
dateValue = range.StartDate.Value.DateTime.Date;
predicate = Expression.AndAlso(predicate, Expression.GreaterThanOrEqual(admittedOnSelector, Expression.Constant(dateValue)));
}
if (range.EndDate.HasValue)
{
dateValue = range.EndDate.Value.DateTime.Date;
predicate = Expression.AndAlso(predicate, Expression.LessThanOrEqual(admittedOnSelector, Expression.Constant(dateValue)));
}
}
}
MethodCallExpression admittedOnWhere = Expressions.Where(encountersProp, Expression.Lambda(predicate, pe_encountersQueryType));
MethodCallExpression orderByAdmittedOn = Expressions.OrderByAscending(admittedOnWhere, Expression.Lambda(admittedOnSelector, pe_encountersQueryType));
//need to cast the return type of the select to a nullable datetime so that the FirstOrDefault will be null as the default
MethodCallExpression admittedOnSelect = Expressions.Select(pe_encountersQueryType.Type, typeof(DateTime?), orderByAdmittedOn, Expression.Lambda(Expression.Convert(admittedOnSelector, typeof(DateTime?)), pe_encountersQueryType));
MethodCallExpression firstOrDefaultAdmittedOn = Expressions.FirstOrDefault <DateTime?>(admittedOnSelect);
if (!HasStratifications)
{
return(new[] {
Expression.Bind(selectType.GetProperty("AdmittedOn"), firstOrDefaultAdmittedOn)
});
}
//if stratified by Month -> return as string in format yyyy-MM
//if stratified by Year -> return as string in format yyyy
DTO.Enums.PeriodStratification stratification;
if (!Enum.TryParse <DTO.Enums.PeriodStratification>(Stratifications.First().ToString(), out stratification))
{
throw new ArgumentException("Unable to parse the specified stratification value as an PeriodStratification: " + Stratifications.First().ToString());
}
Expression prop = Expression.Property(firstOrDefaultAdmittedOn, "Value");
//Expression yearPartString = Expressions.CallToString<int>(Expression.Property(prop, "Year"));
//if (stratification == DTO.Enums.PeriodStratification.Monthly)
//{
// //if stratified by Month -> return as string in format yyyy-MM
// Expression monthPartString = Expressions.CallToString<int>(Expression.Property(prop, "Month"));
// prop = Expressions.ConcatStrings(yearPartString, Expression.Constant("-"), monthPartString);
//}
//else if (stratification == DTO.Enums.PeriodStratification.Yearly)
//{
// //if stratified by Year -> return as string in format yyyy
// prop = yearPartString;
//}
//else
//{
// throw new NotSupportedException("The specified period stratifcation is not currently supported; stratification value: " + Stratifications.First().ToString());
//}
//Expression stratificationModifier = Expression.Condition(Expression.NotEqual(firstOrDefaultAdmittedOn, Expression.Constant(null)), prop, Expression.Constant("", typeof(string)));
//return new[] {
// Expression.Bind(selectType.GetProperty("AdmittedOn"), stratificationModifier)
// };
Expression yearProp = Expression.Property(prop, "Year");
Expression monthProp = Expression.Property(prop, "Month");
return(new[] {
Expression.Bind(selectType.GetProperty("AdmittedOn"), firstOrDefaultAdmittedOn),
Expression.Bind(selectType.GetProperty("AdmittedOnYear"), yearProp),
Expression.Bind(selectType.GetProperty("AdmittedOnMonth"), monthProp)
});
}
