public static DelayedGroup <T> Create(string groupKey, DateTime createAt)
{
var theGroup = new DelayedGroup <T>();
theGroup.GroupKey = groupKey;
theGroup.LastItemDate = createAt;
return(theGroup);
}
public void AppendToGroups(IList <T> items, Func <T, string> getGroupKey, Func <T, DateTime> getAppendAt)
{
if (getGroupKey == null)
{
throw new ArgumentNullException(nameof(getGroupKey));
}
if (getAppendAt == null)
{
throw new ArgumentNullException(nameof(getAppendAt));
}
if (items == null || items.Count == 0)
{
return;
}
lock (Lock)
{
var groups = items.GroupBy(getGroupKey);
foreach (var itemGroup in groups)
{
var groupKey = itemGroup.Key;
var groupItems = itemGroup.ToList();
if (groupItems.Count > 0)
{
var lastItemDate = groupItems.Max(getAppendAt);
DelayedGroups.TryGetValue(groupKey, out var theGroup);
if (theGroup == null)
{
theGroup = DelayedGroup <T> .Create(groupKey, lastItemDate);
DelayedGroups.Add(groupKey, theGroup);
}
theGroup.LastItemDate = lastItemDate;
theGroup.AppendItems(groupItems);
}
}
}
}