private static void AppendField(SwitchModel model, MemberInfo mi)
{
if (mi.GetAttr <SwitchAttribute>() != null)
{ // switch field
if (model.SwitchField != null)
{
throw new InvalidOperationException("duplicate switch attribute");
}
model.SwitchField = new FieldDesc(mi);
foreach (var cAttr in mi.GetAttrs <CaseAttribute>())
{
if (model.Branches.ContainsKey(cAttr.Value))
{
throw new InvalidOperationException("duplicate case value " + cAttr.Value.ToString());
}
model.Branches.Add(cAttr.Value, null);
}
}
else
{ // case field
foreach (var cAttr in mi.GetAttrs <CaseAttribute>())
{
if (model.Branches.ContainsKey(cAttr.Value))
{
throw new InvalidOperationException("duplicate case value " + cAttr.Value.ToString());
}
model.Branches.Add(cAttr.Value, new FieldDesc(mi));
}
}
}
public static Delegate EmitWriter(Type targetType)
{
OrderModel ordModel = OrderModel.Create(targetType);
SwitchModel swModel = SwitchModel.Create(targetType);
if (swModel != null && ordModel != null)
{
throw new InvalidOperationException("unknown way to convert");
}
if (swModel != null)
{
return(swModel.BuildWriter(targetType));
}
if (ordModel != null)
{
return(ordModel.BuildWriter(targetType));
}
return(null);
}
public static SwitchModel Create(Type t)
{
SwitchModel model = new SwitchModel();
model.Branches = new Dictionary <object, FieldDesc>();
foreach (var fi in t.GetFields().Where((fi) => fi.IsPublic && !fi.IsStatic))
{
AppendField(model, fi);
}
foreach (var pi in t.GetProperties().Where((pi) => pi.CanWrite && pi.CanRead))
{
AppendField(model, pi);
}
if (model.SwitchField == null && model.Branches.Count == 0)
{
return(null);
}
if (model.SwitchField == null)
{
throw new InvalidOperationException("switch attribute not found");
}
if (model.Branches.Count <= 1)
{
throw new InvalidOperationException("requires more than two case attributes");
}
if (model.Branches.Values.All((f) => f == null))
{
throw new InvalidOperationException("required no void case attribute");
}
return(model);
}
