public ScanService()
{
_cancelToken = new CancellationTokenSource();
_fileService = new FileService(_cancelToken.Token);
_fileService.NewData += _fileService_NewData;
_pdf = CreateNewDocument();
}
protected virtual void _fileService_NewData(IMessage message)
{
//todo cancellation token support
if (message is NoNewData)
{
//message arrives after max pause interval
if (message.CreatedAt > _lastImageAddedAt + TimePending)
{
SavePdf();
_pdf = CreateNewDocument();
}
return;
}
else if (message is Data)
{
var data = (Data)message;
var imageIndex = GetImageIndex(Path.GetFileName(data.Location));
if (_pdf != null)
{
if (_cancelToken.Token.IsCancellationRequested)
{
SavePdf();
return;
}
if (_lastImageAddedAt - data.CreatedAt > TimePending)
{
SavePdf();
_pdf = CreateNewDocument();
}
if (imageIndex != currentIndex + 1 && currentIndex != -1)
{
SavePdf();
_pdf = CreateNewDocument();
}
}
Debug.Assert(_pdf != null);
_pdf.AddImage(data.Location);
currentIndex = imageIndex;
imageCount++;
_lastImageAddedAt = DateTimeOffset.UtcNow;
_fileService.Delete(new FileInfo(data.Location));
}
}
protected void SavePdf()
{
_pdf.Save(GetNextFilename());
_pdf = null;
}