out of paper detection

Inspectron.Epson/PrintServer/PrintServices/EpsonPrintService.cs

@@ -42,7 +42,8 @@ public class EpsonPrintService: IPrintService
             var status = await epsonPrinter.GetPrinterStatusAsync();
             if (!status.IsOnline)
             {
-                throw new InvalidOperationException("Printer is offline or out of paper.");
+                _logger.LogWarning("Printer {PrinterIp} is out of paper", printerIp);
+                return PrintResult.Fail(PrintErrorType.OutOfPaper);
             }
             var printerAdapter = _wrapperPrinterFactory.CreatePrinterFromId(printerId.Value, epsonPrinter);
 
@@ -101,11 +102,17 @@ public class EpsonPrintService: IPrintService
             status = await epsonPrinter.GetPrinterStatusAsync();
             if (!status.IsOnline)
             {
-                throw new InvalidOperationException("Printer is offline or out of paper.");
+                _logger.LogWarning("Printer {PrinterIp} is out of paper", printerIp);
+                return PrintResult.Fail(PrintErrorType.OutOfPaper);
             }
 
             await printerAdapter.Cut();
         }
+        catch (EpsonConnectionException e)
+        {
+            _logger.LogWarning(e, "Printer {PrinterIp} is offline", printerIp);
+            return PrintResult.Fail(PrintErrorType.Offline);
+        }
         catch (Exception e)
         {
             _logger.LogWarning(e, "Failed to print job for printer {PrinterUid}", printerIp);

Inspectron.Epson/Queue/PrintErrorType.cs

@@ -4,5 +4,7 @@ public enum PrintErrorType
 {
     None,
     ConversionError,
+    Offline,
+    OutOfPaper,
     Other
 }

Inspectron.Epson/Queue/PrinterQueue.cs

@@ -86,6 +86,11 @@ public class PrinterQueue
                                 _logger.LogWarning("Job failed due to conversion error, not re-queuing");
                                 await _statusReporter.ReportStatusAsync(job, PrintJobStatus.Failed);
                             }
+                            else if (result.ErrorType == PrintErrorType.Offline)
+                            {
+                                _logger.LogWarning("Printer is offline, job failed");
+                                await _statusReporter.ReportStatusAsync(job, PrintJobStatus.Failed);
+                            }
                             else
                             {
                                 // Re-queue with retry logic