protected internal override Expression VisitQuerySourceReference(QuerySourceReferenceExpression expression)
{
ModelVisitor.QueryText.AppendFormat(" {0}",
LinqUtility.ResolvePropertyName(expression.ReferencedQuerySource.ItemName));
var mainFromClause = expression.ReferencedQuerySource as MainFromClause;
// .Select(g => g.Select(gList => gList.Age)) subquery select, handle prior groupby source parameter names
if (mainFromClause != null && mainFromClause.FromExpression.Type.Name == "IGrouping`2")
{
var groupByClauses = LinqUtility.PriorGroupBy(ModelVisitor);
for (var i = 0; i < groupByClauses.Count; i++)
{
ModelVisitor.QueryText.AppendFormat("{0}{1}{2}"
, i == 0 ? "." : ""
, LinqUtility.ResolvePropertyName(groupByClauses[i].FromParameterName)
, i != groupByClauses.Count - 1 ? "." : "");
}
}
return(expression);
}
protected override Expression VisitParameter(ParameterExpression expression)
{
var name = expression.Name;
if (expression.Type.Name == "TraversalData`2")
{
var prefix = LinqUtility.MemberNameFromMap(name, "graph", ModelVisitor);
ModelVisitor.QueryText.AppendFormat(" {{ {0} : {1}, {2} : {3}, {4} : {5} }} ",
LinqUtility.ResolvePropertyName("vertex"),
LinqUtility.ResolvePropertyName($"{prefix}_Vertex"),
LinqUtility.ResolvePropertyName("edge"),
LinqUtility.ResolvePropertyName($"{prefix}_Edge"),
LinqUtility.ResolvePropertyName("path"),
LinqUtility.ResolvePropertyName($"{prefix}_Path"));
return(expression);
}
if (expression.Type.Name == "ShortestPathData`2")
{
var prefix = LinqUtility.MemberNameFromMap(name, "graph", ModelVisitor);
ModelVisitor.QueryText.AppendFormat(" {{ {0} : {1}, {2} : {3} }} ",
LinqUtility.ResolvePropertyName("vertex"),
LinqUtility.ResolvePropertyName($"{prefix}_Vertex"),
LinqUtility.ResolvePropertyName("edge"),
LinqUtility.ResolvePropertyName($"{prefix}_Edge"));
return(expression);
}
ModelVisitor.QueryText.AppendFormat(" {0} ", LinqUtility.ResolvePropertyName(name));
return(expression);
}
protected override Expression VisitMember(MemberExpression expression)
{
var member = expression.Expression as MemberExpression;
if (member != null && member.Expression.Type.Name == "IGrouping`2")
{
ModelVisitor.QueryText.AppendFormat(" {0} ", LinqUtility.ResolvePropertyName(expression.Member.Name));
}
// Select(g=>g.Key)
else if (expression.Expression.Type.Name == "IGrouping`2")
{
var groupByClause = LinqUtility.PriorGroupBy(ModelVisitor)[0];
var newExpression = groupByClause.Selector as NewExpression;
if (newExpression != null)
{
ModelVisitor.QueryText.Append(" { ");
for (var i = 0; i < newExpression.Members.Count; i++)
{
var memberName = newExpression.Members[i].Name;
ModelVisitor.QueryText.AppendFormat(" {0} : {1} ",
LinqUtility.ResolvePropertyName(memberName),
LinqUtility.ResolvePropertyName(memberName));
if (i != newExpression.Members.Count - 1)
{
ModelVisitor.QueryText.Append(" , ");
}
}
ModelVisitor.QueryText.Append(" } ");
}
if (groupByClause.Selector.NodeType != ExpressionType.New)
{
ModelVisitor.QueryText.AppendFormat(" {0} ",
LinqUtility.ResolvePropertyName(groupByClause.CollectVariableName));
}
}
else if (expression.Expression.Type.Name == "TraversalData`2" ||
expression.Expression.Type.Name == "ShortestPathData`2")
{
var parameterExpression = expression.Expression as ParameterExpression;
if (parameterExpression == null)
{
throw new InvalidOperationException(
"[TraversalData`2|ShortestPathData`2] VisitMember, expected a ParameterExpression");
}
var prefix = LinqUtility.MemberNameFromMap(parameterExpression.Name, "graph", ModelVisitor);
ModelVisitor.QueryText.AppendFormat(
LinqUtility.ResolvePropertyName($"{prefix}_{expression.Member.Name}"));
}
else
{
Visit(expression.Expression);
ModelVisitor.QueryText.AppendFormat(".{0} ",
LinqUtility.ResolveMemberName(ModelVisitor.Db, expression.Member));
}
return(expression);
}
