internal static void CloneObservableDynamicDataRangeCollection <T>(this IObservableDynamicDataRangeCollection <T> source, IChangeSet <T> changes)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (changes == null)
{
throw new ArgumentNullException(nameof(changes));
}
var i = 0;
foreach (var item in changes)
{
switch (item.Reason)
{
case ListChangeReason.Add:
{
var change = item.Item;
var hasIndex = change.CurrentIndex >= 0;
if (hasIndex)
{
source.Insert(change.CurrentIndex, change.Current);
}
else
{
source.Add(change.Current);
}
break;
}
case ListChangeReason.AddRange:
{
var previousChange = changes.ElementAtOrDefault(i - 1);
if (previousChange != null && previousChange.Reason == ListChangeReason.Clear)
{
source.ReplaceRange(item.Range);
}
else
{
source.AddOrInsertRange(item.Range, item.Range.Index);
}
break;
}
case ListChangeReason.Clear:
{
var nextChange = changes.ElementAtOrDefault(i + 1);
if (nextChange != null && nextChange.Reason != ListChangeReason.AddRange)
{
source.Clear();
}
break;
}
case ListChangeReason.Replace:
{
var change = item.Item;
bool hasIndex = change.CurrentIndex >= 0;
if (hasIndex && change.CurrentIndex == change.PreviousIndex)
{
source[change.CurrentIndex] = change.Current;
}
else
{
source.RemoveAt(change.PreviousIndex);
source.Insert(change.CurrentIndex, change.Current);
}
break;
}
case ListChangeReason.Remove:
{
var change = item.Item;
bool hasIndex = change.CurrentIndex >= 0;
if (hasIndex)
{
source.RemoveAt(change.CurrentIndex);
}
else
{
source.Remove(change.Current);
}
break;
}
case ListChangeReason.RemoveRange:
{
source.RemoveRange(item.Range);
break;
}
case ListChangeReason.Moved:
{
var change = item.Item;
bool hasIndex = change.CurrentIndex >= 0;
if (!hasIndex)
{
throw new UnspecifiedIndexException("Cannot move as an index was not specified");
}
source.Move(change.PreviousIndex, change.CurrentIndex);
break;
}
}
i++;
}
}