feat: add video reuse — re-analyze previous uploads without re-uploading

tests/test_app.py

@@ -67,3 +67,43 @@ def test_api_job_detail_nonexistent(client):
     """GET /api/jobs/nonexistent returns 404."""
     resp = client.get("/api/jobs/nonexistent")
     assert resp.status_code == 404
+
+
+def test_cancel_nonexistent_job(client):
+    """POST /api/jobs/nonexistent/cancel returns 404."""
+    resp = client.post("/api/jobs/nonexistent/cancel")
+    assert resp.status_code == 404
+    data = resp.get_json()
+    assert data["error"] == "not found"
+
+
+def test_cancel_completed_job(client):
+    """POST /api/jobs/<id>/cancel returns 400 for completed job."""
+    from src.job import JobQueue, Job, JobStatus
+    from app import job_queue
+    job = job_queue.add_job(video_path="/tmp/test.mp4", model_configs=[])
+    import time
+    time.sleep(0.3)
+    # Force status to COMPLETED
+    with job_queue._lock:
+        job.status = JobStatus.COMPLETED
+    resp = client.post(f"/api/jobs/{job.job_id}/cancel")
+    assert resp.status_code == 400
+    data = resp.get_json()
+    assert "cannot cancel" in data["error"]
+
+
+def test_cancel_pending_or_running_job(client):
+    """POST /api/jobs/<id>/cancel returns 200 for cancellable job."""
+    from src.job import JobQueue, JobStatus
+    from app import job_queue
+    job = job_queue.add_job(video_path="/tmp/test.mp4", model_configs=[])
+    import time
+    time.sleep(0.1)
+    resp = client.post(f"/api/jobs/{job.job_id}/cancel")
+    assert resp.status_code == 200
+    data = resp.get_json()
+    assert data["status"] == "cancelled"
+    # Verify job is now CANCELLED
+    fetched = job_queue.get_job(job.job_id)
+    assert fetched.status == JobStatus.CANCELLED