private static IEnumerable <OtChange> Normalize(IEnumerable <OtChange> changes)
{
var result = new List <OtChange>();
OtChange prev = null;
foreach (var curr in changes)
{
if (curr.IsId())
{
continue;
}
if (prev is Retain && curr is Retain)
{
prev = new Retain(((Retain)prev).Offset + ((Retain)curr).Offset);
}
else if (prev is InsertText && curr is InsertText)
{
prev = new InsertText(((InsertText)prev).Text + ((InsertText)curr).Text);
}
else if (prev is DeleteText && curr is DeleteText)
{
prev = new DeleteText(((DeleteText)prev).Text + ((DeleteText)curr).Text);
}
else
{
if (prev != null)
{
result.Add(prev);
}
prev = curr;
}
}
if (prev != null)
{
result.Add(prev);
}
if (result.Count == 0)
{
result.Add(new Retain(0));
}
return(result);
}
protected bool Equals(Retain other)
{
return(Offset == other.Offset);
}