private static void AppendFieldComparers <TItem>(FieldComparerGroup <TItem> sourceFieldComparerGroup, FieldComparerGroup destinationFieldComparerGroup)
where TItem : class
{
if ((sourceFieldComparerGroup.Terms.Count() > 1) && (sourceFieldComparerGroup.Operator == LogicalOp.None))
{
throw new ArgumentException($"The logical operator may not be {nameof(LogicalOp.None)} when more than one term is specified!");
}
foreach (SearchTerm <TItem> sourceSearchTerm in sourceFieldComparerGroup.Terms)
{
FieldComparer <TItem> fieldComparer = sourceSearchTerm as FieldComparer <TItem>;
if (fieldComparer != null)
{
destinationFieldComparerGroup.FieldComparers.Add(new FieldComparer
{
FieldName = fieldComparer.FieldName,
Operator = fieldComparer.Operator,
CompareValue = fieldComparer.CompareValue
});
}
else
{
FieldComparerGroup <TItem> sourceSubFieldComparerGroup = sourceSearchTerm as FieldComparerGroup <TItem>;
if (sourceSubFieldComparerGroup != null)
{
var destinationSubFieldComparerGroup = new FieldComparerGroup
{
Operator = sourceSubFieldComparerGroup.Operator
};
AppendFieldComparers(sourceSubFieldComparerGroup, destinationSubFieldComparerGroup);
if (destinationSubFieldComparerGroup.FieldComparers.Count + destinationSubFieldComparerGroup.FieldComparerGroups.Count > 0)
{
destinationFieldComparerGroup.FieldComparerGroups.Add(destinationSubFieldComparerGroup);
}
}
else
{
throw new ArgumentException($"Unknown search term: {sourceSearchTerm?.GetType()}");
}
}
}
}
private static Expression ExpressionFromFieldComparerGroup <T>(FieldComparerGroup fieldComparerGroup, ParameterExpression param, SearchIntent searchIntent)
where T : class
{
Expression search = null;
foreach (FieldComparer fieldComparer in fieldComparerGroup.FieldComparers)
{
// The expression tree we are building
PropertyInfo propertyInfo = GetPropertyWithValidation <T>(fieldComparer.FieldName);
if (propertyInfo == null)
{
throw new Exception($"The column '{fieldComparer.FieldName}' does not exist in my dataclass");
}
object convertedSearchValue = GetConvertedSearchValue(propertyInfo, fieldComparer);
Expression searchWithType;
// ReSharper disable once PossibleNullReferenceException
if (propertyInfo.PropertyType == typeof(Guid) && Guid.Empty.Equals((Guid)convertedSearchValue))
{
searchWithType = Expression.Field(null, typeof(Guid), "Empty");
convertedSearchValue = Guid.Empty;
}
else
{
searchWithType = Expression.Constant(convertedSearchValue);
}
MemberExpression memberExpression = Expression.PropertyOrField(param, fieldComparer.FieldName);
Expression body;
switch (fieldComparer.Operator)
{
case CompareOp.Equals:
body = SearcherExpressionExtensions.Equals(memberExpression, searchWithType, searchIntent);
break;
case CompareOp.NotEquals:
body = SearcherExpressionExtensions.NotEqual(memberExpression, searchWithType);
break;
case CompareOp.GreaterThanOrEqual:
body = SearcherExpressionExtensions.GreaterThanOrEqual(memberExpression, searchWithType);
break;
case CompareOp.LessThanOrEqual:
body = SearcherExpressionExtensions.LessThanOrEqual(memberExpression, searchWithType);
break;
case CompareOp.LessThan:
body = SearcherExpressionExtensions.LessThan(memberExpression, searchWithType);
break;
case CompareOp.GreaterThan:
body = SearcherExpressionExtensions.GreaterThan(memberExpression, searchWithType);
break;
//case CompareOp.EqualsCaseSensitive:
// body = SearcherExpressionExtensions.Equal(memberExpression, searchWithType);
// break;
case CompareOp.StartsWith:
body = SearcherExpressionExtensions.StartsWith(memberExpression, searchWithType, searchIntent);
break;
//case CompareOp.StartsWithCaseSensitive:
// body = SearcherExpressionExtensions.StartsWith(memberExpression, searchWithType);
// break;
case CompareOp.Contains:
body = SearcherExpressionExtensions.Contains(memberExpression, searchWithType, searchIntent);
break;
//case CompareOp.ContainsCaseSensitive:
// body = SearcherExpressionExtensions.Contains(memberExpression, searchWithType);
// break;
case CompareOp.EndsWith:
body = SearcherExpressionExtensions.EndsWith(memberExpression, searchWithType, searchIntent);
break;
//case CompareOp.EndsWithOrdinalIgnoreCase:
// body = SearcherExpressionExtensions.EndsWithOrdinalIgnoreCase(memberExpression, searchWithType);
// break;
case CompareOp.Match:
body = SearcherExpressionExtensions.Match(memberExpression, convertedSearchValue, searchIntent);
break;
default:
throw new Exception($"Search term {fieldComparer.Operator} not supported");
}
if (search == null)
{
search = body;
}
else
{
search = fieldComparerGroup.Operator == LogicalOp.And
? Expression.AndAlso(search, body)
: Expression.OrElse(search, body);
}
}
foreach (FieldComparerGroup subFieldComparerGroup in fieldComparerGroup.FieldComparerGroups)
{
var subExpression = ExpressionFromFieldComparerGroup <T>(subFieldComparerGroup, param, searchIntent);
if (search == null)
{
search = subExpression;
}
else
{
search = fieldComparerGroup.Operator == LogicalOp.And
? Expression.AndAlso(search, subExpression)
: Expression.OrElse(search, subExpression);
}
}
return(search ?? Expression.Constant(true));
}
