fix stale state after ffmpeg exit

server/src/services/transcoding.service.spec.ts

@@ -177,6 +177,29 @@ describe(TranscodingService.name, () => {
 
       expect(mocks.process.spawn).not.toHaveBeenCalled();
     });
+
+    it('accepts segments from a restart after the previous ffmpeg exited on its own', async () => {
+      const first = mockSpawn(0, '', '');
+      const second = mockSpawn(0, '', '');
+      mocks.process.spawn.mockReturnValueOnce(first).mockReturnValueOnce(second);
+
+      await sut.onSegmentRequest({ sessionId, assetId, variantIndex: 0, segmentIndex: 10 });
+      completeSegment(10);
+
+      const onCalls = vi.mocked(first.on).mock.calls as unknown as [string, (code: number) => void][];
+      const exitHandler = onCalls.find(([event]) => event === 'exit')?.[1];
+      exitHandler?.(0);
+
+      mocks.websocket.serverSend.mockClear();
+      await sut.onSegmentRequest({ sessionId, assetId, variantIndex: 0, segmentIndex: 2 });
+      completeSegment(2);
+
+      expect(mocks.websocket.serverSend).toHaveBeenCalledWith('HlsSegmentResult', {
+        sessionId,
+        variantIndex: 0,
+        segmentIndex: 2,
+      });
+    });
   });
 
   describe('backpressure', () => {

server/src/services/transcoding.service.ts

@@ -304,6 +304,7 @@ export class TranscodingService extends BaseService {
       }
       session.paused = false;
       session.process = null;
+      session.lastCompletedSegment = null;
       if (code) {
         this.logger.error(
           `FFmpeg exited with code ${code} for variant ${variantIndex} asset ${session.assetId}\n${stderr}`,