public static ISolrQuery ConditionalQuery(
this ConditionalExpression expression,
Func<Expression,Expression> ifTrueBuilder,
Func<Expression, Expression> ifFalseBuilder,
MemberContext context)
{
ISolrQuery testPositive = expression.Test.GetSolrFilterQuery(context);
ISolrQuery trueCase = ifTrueBuilder(expression.IfTrue).GetSolrFilterQuery(context);
ISolrQuery testNegative = testPositive.CreateNotSolrQuery();
ISolrQuery falseCase = ifFalseBuilder(expression.IfFalse).GetSolrFilterQuery(context);
return GetMultipleCriteriaQuery(
GetMultipleCriteriaQuery(testPositive, trueCase, SolrMultipleCriteriaQuery.Operator.AND),
GetMultipleCriteriaQuery(testNegative, falseCase, SolrMultipleCriteriaQuery.Operator.AND),
SolrMultipleCriteriaQuery.Operator.OR);
}
public static ISolrQuery GetSolrFilterQuery(this Expression expression, MemberContext context)
{
expression = expression.HandleConversion();
ExpressionType nodeType = expression.NodeType;
// No member access, try to calculate constant expression
if (!context.HasMemberAccess(expression))
{
return ConstantToConstant(expression, Expression.Constant(true), (a, b) => (bool)a == (bool)b);
}
if (expression is BinaryExpression binaryExpression)
{
switch (nodeType)
{
case ExpressionType.AndAlso:
{
ISolrQuery left = GetSolrFilterQuery(binaryExpression.Left, context);
ISolrQuery right = GetSolrFilterQuery(binaryExpression.Right, context);
string op = SolrMultipleCriteriaQuery.Operator.AND;
return GetMultipleCriteriaQuery(left, right, op);
}
case ExpressionType.OrElse:
{
ISolrQuery left = GetSolrFilterQuery(binaryExpression.Left, context);
ISolrQuery right = GetSolrFilterQuery(binaryExpression.Right, context);
string op = SolrMultipleCriteriaQuery.Operator.OR;
return GetMultipleCriteriaQuery(left, right, op);
}
case ExpressionType.Equal:
{
return binaryExpression.HandleEqual(context);
}
case ExpressionType.NotEqual:
{
Tuple<Expression, Expression, bool> memberToLeft = binaryExpression.MemberToLeft(context);
KeyValuePair<string, string> kvp = memberToLeft.MemberValue(context);
return kvp.Value == null
? new SolrHasValueQuery(kvp.Key)
: new SolrQueryByField(kvp.Key, kvp.Value).CreateNotSolrQuery();
}
case ExpressionType.GreaterThan:
case ExpressionType.GreaterThanOrEqual:
case ExpressionType.LessThan:
case ExpressionType.LessThanOrEqual:
{
return binaryExpression.HandleComparison(context);
}
}
}
if (expression is UnaryExpression unaryExpression)
{
switch (nodeType)
{
case ExpressionType.Not:
{
ISolrQuery operand = GetSolrFilterQuery(unaryExpression.Operand, context);
ISolrQuery result = operand.CreateNotSolrQuery();
return result;
}
}
}
if (expression is MethodCallExpression methodCallExpression)
{
return methodCallExpression.HandleMethodCall(context);
}
if (expression is MemberExpression memberExpression)
{
return memberExpression.HandleMemberAccess(context);
}
if (expression is ConditionalExpression conditionalExpression)
{
return ConditionalQuery(conditionalExpression, t => t, f => f, context);
}
throw new InvalidOperationException(
$"Node type {nodeType} not supported in filter query");
}