void ISearchValueVisitor.Visit(TokenSearchValue token)
{
EnsureArg.IsNotNull(token, nameof(token));
EnsureOnlyEqualComparatorIsSupported();
if (_modifier == null)
{
_outputExpression = BuildEqualityExpression();
}
else if (_modifier == SearchModifierCode.Not)
{
_outputExpression = Expression.Not(BuildEqualityExpression());
}
else if (_modifier == SearchModifierCode.Above ||
_modifier == SearchModifierCode.Below ||
_modifier == SearchModifierCode.In ||
_modifier == SearchModifierCode.NotIn)
{
// These modifiers are not supported yet but will be supported eventually.
ThrowModifierNotSupported();
}
else
{
ThrowModifierNotSupported();
}
Expression BuildEqualityExpression()
{
// Based on spec http://hl7.org/fhir/search.html#token,
// we need to make sure to test if system is missing or not based on how it is supplied.
if (token.System == null)
{
// If the system is not supplied, then the token code is matched irrespective of the value of system.
return(Expression.StringEquals(FieldName.TokenCode, _componentIndex, token.Code, false));
}
else if (token.System.Length == 0)
{
// If the system is empty, then the token is matched if there is no system property.
return(Expression.And(
Expression.Missing(FieldName.TokenSystem, _componentIndex),
Expression.StringEquals(FieldName.TokenCode, _componentIndex, token.Code, false)));
}
else if (string.IsNullOrWhiteSpace(token.Code))
{
// If the code is empty, then the token is matched if system is matched.
return(Expression.StringEquals(FieldName.TokenSystem, _componentIndex, token.System, false));
}
else
{
return(Expression.And(
Expression.StringEquals(FieldName.TokenSystem, _componentIndex, token.System, false),
Expression.StringEquals(FieldName.TokenCode, _componentIndex, token.Code, false)));
}
}
}
void ISearchValueVisitor.Visit(ReferenceSearchValue reference)
{
EnsureArg.IsNotNull(reference, nameof(reference));
if (_modifier != null)
{
ThrowModifierNotSupported();
}
EnsureOnlyEqualComparatorIsSupported();
if (reference.BaseUri != null)
{
// The reference is external.
_outputExpression = Expression.And(
Expression.StringEquals(FieldName.ReferenceBaseUri, _componentIndex, reference.BaseUri.ToString(), false),
Expression.StringEquals(FieldName.ReferenceResourceType, _componentIndex, reference.ResourceType.Value.ToString(), false),
Expression.StringEquals(FieldName.ReferenceResourceId, _componentIndex, reference.ResourceId, false));
}
else if (reference.ResourceType == null)
{
// Only resource id is specified.
_outputExpression = Expression.StringEquals(FieldName.ReferenceResourceId, _componentIndex, reference.ResourceId, false);
}
else if (reference.Kind == ReferenceKind.Internal)
{
// The reference must be internal.
_outputExpression = Expression.And(
Expression.Missing(FieldName.ReferenceBaseUri, _componentIndex),
Expression.StringEquals(FieldName.ReferenceResourceType, _componentIndex, reference.ResourceType.Value.ToString(), false),
Expression.StringEquals(FieldName.ReferenceResourceId, _componentIndex, reference.ResourceId, false));
}
else
{
// The reference can be internal or external.
_outputExpression = Expression.And(
Expression.StringEquals(FieldName.ReferenceResourceType, _componentIndex, reference.ResourceType.Value.ToString(), false),
Expression.StringEquals(FieldName.ReferenceResourceId, _componentIndex, reference.ResourceId, false));
}
}
