private TResult GetOriginalValue <TResult>(T target, Expression <Func <T, TResult> > selector)
{
var propertyInfo = GetPropertyInfo(selector);
string propName = propertyInfo.Name;
TResult originalValue = _OriginalValueDictionary.TryGetValue(propName, out object value) ?
(TResult)value :
selector.Compile()(target);
if (originalValue is IChangeTrackableInternal trackable)
{
UnrollGraph unrollGraph = new UnrollGraph();
originalValue = (TResult)trackable.GetOriginal(unrollGraph);
unrollGraph.FinishWireUp();
}
return(originalValue);
}
public void Intercept(IInvocation invocation)
{
if (!IsInitialized)
{
return;
}
if (invocation.Method.IsSetter() && !_InRejectChanges)
{
if (_ChangeTrackingStatus == ChangeStatus.Deleted)
{
throw new InvalidOperationException("Can not modify deleted object");
}
string propertyName = invocation.Method.PropertyName();
object previousValue = _Properties[propertyName].GetValue(invocation.Proxy, null);
invocation.Proceed();
object newValue = _Properties[propertyName].GetValue(invocation.Proxy, null);
if (!ReferenceEquals(previousValue, newValue))
{
UnsubscribeFromChildStatusChanged(propertyName, previousValue);
SubscribeToChildStatusChanged(invocation.Proxy, propertyName, newValue);
}
bool originalValueFound = _OriginalValueDictionary.TryGetValue(propertyName, out object originalValue);
if (!originalValueFound && !Equals(previousValue, newValue))
{
_OriginalValueDictionary.Add(propertyName, previousValue);
SetAndRaiseStatusChanged(invocation.Proxy, parents: new List <object> {
invocation.Proxy
}, setStatusEvenIfStatsAddedOrDeleted: false);
}
else if (originalValueFound && Equals(originalValue, newValue))
{
_OriginalValueDictionary.Remove(propertyName);
SetAndRaiseStatusChanged(invocation.Proxy, parents: new List <object> {
invocation.Proxy
}, setStatusEvenIfStatsAddedOrDeleted: false);
}
return;
}
else if (invocation.Method.IsGetter())
{
string propertyName = invocation.Method.PropertyName();
if (propertyName == nameof(IChangeTrackable.ChangeTrackingStatus))
{
invocation.ReturnValue = _ChangeTrackingStatus;
}
else if (propertyName == nameof(System.ComponentModel.IChangeTracking.IsChanged))
{
invocation.ReturnValue = _ChangeTrackingStatus != ChangeStatus.Unchanged;
}
else if (propertyName == nameof(IChangeTrackable.ChangedProperties))
{
invocation.ReturnValue = GetChangedProperties();
}
else
{
invocation.Proceed();
SubscribeToChildStatusChanged(invocation.Proxy, propertyName, invocation.ReturnValue);
}
return;
}
switch (invocation.Method.Name)
{
case nameof(IChangeTrackable <object> .GetOriginalValue):
invocation.ReturnValue = ((dynamic)this).GetOriginalValue((T)invocation.Proxy, (dynamic)invocation.Arguments[0]);
break;
case nameof(IChangeTrackable <object> .GetOriginal):
case nameof(IChangeTrackable <object> .GetCurrent):
object poco;
Func <PropertyInfo, object, object> getPropertyProxy;
Func <IChangeTrackableInternal, UnrollGraph, object> getPropertyPoco;
if (invocation.Method.Name == nameof(IChangeTrackable <object> .GetOriginal))
{
getPropertyProxy = (property, proxy) => _OriginalValueDictionary.TryGetValue(property.Name, out object value) ? value : property.GetValue(proxy, null);
getPropertyPoco = (proxy, g) => proxy.GetOriginal(g);
}
else
{
getPropertyProxy = (property, proxy) => property.GetValue(proxy, null);
getPropertyPoco = (proxy, g) => proxy.GetCurrent(g);
}
bool isRootCall = invocation.Arguments.Length == 0;
if (isRootCall)
{
UnrollGraph unrollGraph = new UnrollGraph();
poco = GetPoco((T)invocation.Proxy, unrollGraph, getPropertyProxy, getPropertyPoco);
unrollGraph.FinishWireUp();
}
else
{
poco = GetPoco((T)invocation.Proxy, (UnrollGraph)invocation.Arguments[0], getPropertyProxy, getPropertyPoco);
}
invocation.ReturnValue = poco;
break;
case "add_StatusChanged":
_StatusChanged += (EventHandler)invocation.Arguments[0];
break;
case "remove_StatusChanged":
_StatusChanged -= (EventHandler)invocation.Arguments[0];
break;
case "Delete":
invocation.ReturnValue = Delete(invocation.Proxy);
break;
case "UnDelete":
invocation.ReturnValue = UnDelete(invocation.Proxy);
break;
case nameof(IRevertibleChangeTrackingInternal.AcceptChanges):
AcceptChanges(invocation.Proxy, invocation.Arguments.Length == 0 ? null : (List <object>)invocation.Arguments[0]);
break;
case nameof(IRevertibleChangeTrackingInternal.RejectChanges):
RejectChanges(invocation.Proxy, invocation.Arguments.Length == 0 ? null : (List <object>)invocation.Arguments[0]);
break;
case nameof(IRevertibleChangeTrackingInternal.IsChanged):
invocation.ReturnValue = GetNewChangeStatus(invocation.Proxy, (List <object>)invocation.Arguments[0]) != ChangeStatus.Unchanged;
break;
default:
invocation.Proceed();
break;
}
}