private (int, Encoding)? GetLengthAttributeValues(MemberAttributeInfo fieldAttributes, ValueStorage storage)
{
var fixedLengthAttribute = fieldAttributes?.FixedLengthAttribute;
var variableLengthAttribute = fieldAttributes?.VariableLengthAttribute;
var calculatedLengthAttribute = fieldAttributes?.CalculatedLengthAttribute;
Encoding stringEncoding;
int length;
if (fixedLengthAttribute != null)
{
stringEncoding = Tools.RetrieveEncoding(fixedLengthAttribute.StringEncoding);
length = fixedLengthAttribute.Length;
}
else if (variableLengthAttribute != null)
{
stringEncoding = Tools.RetrieveEncoding(variableLengthAttribute.StringEncoding);
length = Convert.ToInt32(storage.Get(variableLengthAttribute.FieldName)) + variableLengthAttribute.Offset;
}
else if (calculatedLengthAttribute != null)
{
stringEncoding = Tools.RetrieveEncoding(calculatedLengthAttribute.StringEncoding);
length = calculatedLengthAttribute.CalculationAction(storage);
}
else
{
return(null);
}
return(length, stringEncoding);
}
private bool ResolveCondition(ConditionAttribute condition, ValueStorage storage)
{
// If no condition is given, resolve it to true so the field is read
if (condition == null)
{
return(true);
}
var value = storage.Get(condition.FieldName);
switch (condition.Comparer)
{
case ConditionComparer.Equal:
return(Convert.ToUInt64(value) == condition.Value);
case ConditionComparer.Greater:
return(Convert.ToUInt64(value) > condition.Value);
case ConditionComparer.Smaller:
return(Convert.ToUInt64(value) < condition.Value);
case ConditionComparer.GEqual:
return(Convert.ToUInt64(value) >= condition.Value);
case ConditionComparer.SEqual:
return(Convert.ToUInt64(value) <= condition.Value);
default:
throw new InvalidOperationException($"Unknown comparer {condition.Comparer}.");
}
}
private Type ChooseType(Type readType, MemberAttributeInfo fieldAttributes, ValueStorage storage)
{
var typeChoices = fieldAttributes.TypeChoiceAttributes.ToArray();
if (readType != typeof(object) && typeChoices.Any(x => !readType.IsAssignableFrom(x.InjectionType)))
{
throw new InvalidOperationException($"Not all type choices are injectable to '{readType.Name}'.");
}
Type chosenType = null;
foreach (var typeChoice in typeChoices)
{
if (!storage.Exists(typeChoice.FieldName))
{
throw new InvalidOperationException($"Field '{typeChoice.FieldName}' could not be found.");
}
var value = storage.Get(typeChoice.FieldName);
switch (typeChoice.Comparer)
{
case TypeChoiceComparer.Equal:
if (Convert.ToUInt64(value) == Convert.ToUInt64(typeChoice.Value))
{
chosenType = typeChoice.InjectionType;
}
break;
case TypeChoiceComparer.Greater:
if (Convert.ToUInt64(value) > Convert.ToUInt64(typeChoice.Value))
{
chosenType = typeChoice.InjectionType;
}
break;
case TypeChoiceComparer.Smaller:
if (Convert.ToUInt64(value) < Convert.ToUInt64(typeChoice.Value))
{
chosenType = typeChoice.InjectionType;
}
break;
case TypeChoiceComparer.GEqual:
if (Convert.ToUInt64(value) >= Convert.ToUInt64(typeChoice.Value))
{
chosenType = typeChoice.InjectionType;
}
break;
case TypeChoiceComparer.SEqual:
if (Convert.ToUInt64(value) <= Convert.ToUInt64(typeChoice.Value))
{
chosenType = typeChoice.InjectionType;
}
break;
default:
throw new InvalidOperationException($"Unknown comparer {typeChoice.Comparer}.");
}
if (chosenType != null)
{
break;
}
}
if (chosenType == null)
{
throw new InvalidOperationException($"No choice matched the criteria for injection");
}
return(chosenType);
}