private static void BuildArgs(BinaryExpression expression, TimeLineArgs args)
{
if (expression.Left.NodeType != ExpressionType.MemberAccess)
{
throw new NotSupportedException(string.Format("Expression {0} not supported", expression.Left));
}
MemberExpression me = (MemberExpression) expression.Left;
if (!me.Member.IsProperty<Status, long>(t => t.Id))
{
throw new NotSupportedException(String.Format("Expression {0} not supported", me));
}
long id = ((IConvertible)((ConstantExpression)expression.Right).Value).ToInt64(CultureInfo.InvariantCulture);
switch (expression.NodeType)
{
case ExpressionType.GreaterThanOrEqual:
args.SinceId = id;
break;
case ExpressionType.LessThanOrEqual:
args.MaxId = id;
break;
default:
throw new NotSupportedException(
String.Format("Expression of type {0} not supported", expression.NodeType));
}
}
private static void HandleTakeArgs(Expression expression, TimeLineArgs args)
{
MethodInfo info = MethodInfoForTake();
MethodCallFinderVisitor visitor = new MethodCallFinderVisitor(info);
if (visitor.FindMethod(expression))
{
args.Count = Convert.ToInt32(visitor.Args.First());
}
}
public object Execute(Expression expression, bool isEnumerable)
{
TimeLineArgs args = new TimeLineArgs();
HandleWhereArgs(expression, args);
HandleTakeArgs(expression, args);
HandlePageArgs(expression, args);
return _statusFunc(args);
}
private void HandlePageArgs(Expression expression, TimeLineArgs args)
{
MethodInfo info = MethodInfoForPage();
MethodCallFinderVisitor visitor = new MethodCallFinderVisitor(info);
if (visitor.FindMethod(expression))
{
args.Page = Convert.ToInt32(visitor.Args.First());
}
}
private void HandleWhereArgs(Expression expression, TimeLineArgs args)
{
var whereVisitor = new WhereVisitor();
MethodCallExpression whereExpression = whereVisitor.FindWhere(expression);
if (whereExpression == null)
{
return;
}
LambdaExpression lambdaExpression =
(LambdaExpression)
((UnaryExpression)whereExpression.Arguments[1]).Operand;
var idVisitor = new IdExpressionVisitor();
if (!idVisitor.FindIdExpression(lambdaExpression))
{
return;
}
foreach (BinaryExpression binaryExpression in idVisitor.Expressions)
{
BuildArgs(binaryExpression, args);
}
}
private Status[] RetrieveStatuses(TimeLineArgs args)
{
_args = args;
return _statusesToReturn;
}
