internal static bool TryMatchDiscriminatorPredicate(
DbFilterExpression filter,
Action <DbComparisonExpression, object> onMatchedComparison)
{
EdmProperty edmProperty = (EdmProperty)null;
foreach (DbExpression expression in ViewSimplifier.FlattenOr(filter.Predicate))
{
DbPropertyExpression property;
object obj;
if (!ViewSimplifier.TryMatchPropertyEqualsValue(expression, filter.Input.VariableName, out property, out obj))
{
return(false);
}
if (edmProperty == null)
{
edmProperty = (EdmProperty)property.Property;
}
else if (edmProperty != property.Property)
{
return(false);
}
onMatchedComparison((DbComparisonExpression)expression, obj);
}
return(true);
}
private static DbExpression SimplifyNestedTphDiscriminator(DbExpression expression)
{
DbProjectExpression projectExpression = (DbProjectExpression)expression;
DbFilterExpression booleanColumnFilter = (DbFilterExpression)projectExpression.Input.Expression;
DbProjectExpression expression1 = (DbProjectExpression)booleanColumnFilter.Input.Expression;
DbFilterExpression expression2 = (DbFilterExpression)expression1.Input.Expression;
List <DbExpression> list1 = ViewSimplifier.FlattenOr(booleanColumnFilter.Predicate).ToList <DbExpression>();
List <DbPropertyExpression> list2 = list1.OfType <DbPropertyExpression>().Where <DbPropertyExpression>((Func <DbPropertyExpression, bool>)(px =>
{
if (px.Instance.ExpressionKind == DbExpressionKind.VariableReference)
{
return(((DbVariableReferenceExpression)px.Instance).VariableName == booleanColumnFilter.Input.VariableName);
}
return(false);
})).ToList <DbPropertyExpression>();
if (list1.Count != list2.Count)
{
return((DbExpression)null);
}
List <string> list3 = list2.Select <DbPropertyExpression, string>((Func <DbPropertyExpression, string>)(px => px.Property.Name)).ToList <string>();
Dictionary <object, DbComparisonExpression> discriminatorPredicates = new Dictionary <object, DbComparisonExpression>();
if (!TypeSemantics.IsEntityType(expression2.Input.VariableType) || !ViewSimplifier.TryMatchDiscriminatorPredicate(expression2, (Action <DbComparisonExpression, object>)((compEx, discValue) => discriminatorPredicates.Add(discValue, compEx))))
{
return((DbExpression)null);
}
EdmProperty property1 = (EdmProperty)((DbPropertyExpression)discriminatorPredicates.First <KeyValuePair <object, DbComparisonExpression> >().Value.Left).Property;
DbNewInstanceExpression projection1 = (DbNewInstanceExpression)expression1.Projection;
RowType edmType = TypeHelpers.GetEdmType <RowType>(projection1.ResultType);
Dictionary <string, DbComparisonExpression> dictionary1 = new Dictionary <string, DbComparisonExpression>();
Dictionary <string, DbComparisonExpression> dictionary2 = new Dictionary <string, DbComparisonExpression>();
Dictionary <string, DbExpression> propertyValues = new Dictionary <string, DbExpression>(projection1.Arguments.Count);
for (int index = 0; index < projection1.Arguments.Count; ++index)
{
string name = edmType.Properties[index].Name;
DbExpression dbExpression = projection1.Arguments[index];
if (list3.Contains(name))
{
if (dbExpression.ExpressionKind != DbExpressionKind.Case)
{
return((DbExpression)null);
}
DbCaseExpression dbCaseExpression = (DbCaseExpression)dbExpression;
if (dbCaseExpression.When.Count != 1 || !TypeSemantics.IsBooleanType(dbCaseExpression.Then[0].ResultType) || (!TypeSemantics.IsBooleanType(dbCaseExpression.Else.ResultType) || dbCaseExpression.Then[0].ExpressionKind != DbExpressionKind.Constant) || (dbCaseExpression.Else.ExpressionKind != DbExpressionKind.Constant || !(bool)((DbConstantExpression)dbCaseExpression.Then[0]).Value || (bool)((DbConstantExpression)dbCaseExpression.Else).Value))
{
return((DbExpression)null);
}
DbPropertyExpression property2;
object key;
if (!ViewSimplifier.TryMatchPropertyEqualsValue(dbCaseExpression.When[0], expression1.Input.VariableName, out property2, out key) || property2.Property != property1 || !discriminatorPredicates.ContainsKey(key))
{
return((DbExpression)null);
}
dictionary1.Add(name, discriminatorPredicates[key]);
dictionary2.Add(name, (DbComparisonExpression)dbCaseExpression.When[0]);
}
else
{
propertyValues.Add(name, dbExpression);
}
}
DbExpression predicate = Helpers.BuildBalancedTreeInPlace <DbExpression>((IList <DbExpression>) new List <DbExpression>((IEnumerable <DbExpression>)dictionary1.Values), (Func <DbExpression, DbExpression, DbExpression>)((left, right) => (DbExpression)left.Or(right)));
DbFilterExpression input = expression2.Input.Filter(predicate);
DbCaseExpression projection2 = (DbCaseExpression)projectExpression.Projection;
List <DbExpression> dbExpressionList1 = new List <DbExpression>(projection2.When.Count);
List <DbExpression> dbExpressionList2 = new List <DbExpression>(projection2.Then.Count);
for (int index = 0; index < projection2.When.Count; ++index)
{
DbPropertyExpression propertyExpression = (DbPropertyExpression)projection2.When[index];
DbNewInstanceExpression instanceExpression = (DbNewInstanceExpression)projection2.Then[index];
DbComparisonExpression comparisonExpression;
if (!dictionary2.TryGetValue(propertyExpression.Property.Name, out comparisonExpression))
{
return((DbExpression)null);
}
dbExpressionList1.Add((DbExpression)comparisonExpression);
DbExpression dbExpression = ViewSimplifier.ValueSubstituter.Substitute((DbExpression)instanceExpression, projectExpression.Input.VariableName, propertyValues);
dbExpressionList2.Add(dbExpression);
}
DbExpression elseExpression = ViewSimplifier.ValueSubstituter.Substitute(projection2.Else, projectExpression.Input.VariableName, propertyValues);
DbCaseExpression dbCaseExpression1 = DbExpressionBuilder.Case((IEnumerable <DbExpression>)dbExpressionList1, (IEnumerable <DbExpression>)dbExpressionList2, elseExpression);
return((DbExpression)input.BindAs(expression1.Input.VariableName).Project((DbExpression)dbCaseExpression1));
}