/// <summary>
/// Merges two tags with the same tag name by merging the tagged paths in each tag
/// </summary>
/// <param name="current">The <see cref="Tag">Tag</see> object that represents the current tag</param>
/// <param name="newTag">The <see cref="Tag">Tag</see> object that represents the new tag</param>
/// <returns>true if the tags are merged, false if the tags have different tag name or
/// same last updated date or different last updated date</returns>
private static bool MergeTag(Tag current, Tag newTag)
{
if (!newTag.TagName.ToLower().Equals(current.TagName.ToLower()))
{
//Since Tag name is different , do not merge.
//Should not Happen.
return false;
}
if (newTag.LastUpdatedDate == current.LastUpdatedDate)
{
//Since Tag updated time is same , shall not do anything
return false;
}
else
{//Since time different , merge.
//if new Tag is deleted and current is not
if (newTag.IsDeleted && !current.IsDeleted)
{
//delete only if deleted date is more than created date.
if (newTag.DeletedDate > current.CreatedDate)
{
ServiceLocator.LogicLayerNotificationQueue().Enqueue(new RemoveTagNotification(newTag));
return true;
}
//do nothing
return false;
}
//for each taggedPath found in the new Tag.
//if the path is not found , just create
//if the path is found , attempt to merge.
if (current.IsDeleted && !newTag.IsDeleted)
{
if (newTag.CreatedDate > current.DeletedDate)
{
TaggingLayer.Instance.AddTag(newTag);
ServiceLocator.LogicLayerNotificationQueue().Enqueue(new AddTagNotification(newTag));
return true;
}
}
foreach (TaggedPath newPath in newTag.UnfilteredPathList)
{
TaggedPath currentPath = current.FindPath(newPath.PathName, false);
if (currentPath == null)
{
ServiceLocator.LogicLayerNotificationQueue().Enqueue(new MonitorPathNotification(current,newPath));
current.AddPath(newPath);
}
else
{
//update only if the new path is more updated than the current path
if (currentPath.LastUpdatedDate <= newPath.LastUpdatedDate)
{
//if the path is delete in the new tag but not in the old tag
if (newPath.IsDeleted && !currentPath.IsDeleted)
{
if (newPath.DeletedDate > currentPath.CreatedDate)
{
current.RemovePath(newPath);
ServiceLocator.LogicLayerNotificationQueue().Enqueue(new UnMonitorPathNotification(current,newPath));
}
}
else if (!newPath.IsDeleted && currentPath.IsDeleted)
{
if (newPath.CreatedDate > currentPath.DeletedDate)
{
//a new path is created in the new tag but is deleted in the old tag.
current.AddPath(newPath);
ServiceLocator.LogicLayerNotificationQueue().Enqueue(new MonitorPathNotification(current,newPath));
}
}
}
}
}
}
return true;
}
