fix: release consumed restore references and explain deletion protection [skip ci]

tests/test_display.py

@@ -145,6 +145,105 @@ def test_delete_restore_reference_protected(service):
     service.process_one()
     assert service.operation(delete)["status"] == "FAILED"
     assert service.operation(delete)["error"]["code"] == "CONFLICT"
+    assert (
+        service.operation(delete)["error"]["details"]["reason"]
+        == "RESTORE_IMAGE_PROTECTED"
+    )
+
+
+@pytest.mark.parametrize("automatic", [True, False])
+def test_completed_restore_consumes_self_reference(client, service, automatic):
+    display = submit(service, 60, True)
+    service.process_one()
+    service.sync()
+    if automatic:
+        expired(service, display)
+        service.expire()
+    else:
+        service.submit("restore", {}, "living-room", "admin", "restore-test")
+        service.process_one()
+    service.sync()
+    assert service.state("living-room")["previous_image_id"] is None
+    assert not client.get("/api/v1/devices/living-room").json()["can_restore"]
+    delete = service.submit(
+        "delete",
+        {"image_id": 1, "confirm_current": True},
+        "living-room",
+        "admin",
+        "delete-restored",
+    )
+    service.process_one()
+    assert service.operation(delete)["status"] == "COMPLETED"
+
+
+@pytest.mark.parametrize("via_delete", [False, True])
+def test_existing_self_reference_is_repaired(client, service, via_delete):
+    service.state("living-room")
+    service.db.execute(
+        "UPDATE device_state SET previous_image_id=1,managed_image_id=1 WHERE device_id=?",
+        ("living-room",),
+    )
+    if via_delete:
+        operation = service.submit(
+            "delete",
+            {"image_id": 1, "confirm_current": True},
+            "living-room",
+            "admin",
+            "delete-stale-reference",
+        )
+        service.process_one()
+        assert service.operation(operation)["status"] == "COMPLETED"
+    else:
+        assert not client.get("/api/v1/devices/living-room?refresh=true").json()[
+            "can_restore"
+        ]
+    assert service.state("living-room")["previous_image_id"] is None
+
+
+@pytest.mark.parametrize(
+    "protection",
+    ["override", "base", "unsynced", "unknown", "syncing", "other_previous"],
+)
+def test_self_reference_cleanup_preserves_real_restore_requirements(
+    service, protection
+):
+    service.state("living-room")
+    service.db.execute(
+        "UPDATE device_state SET previous_image_id=1,managed_image_id=1 WHERE device_id=?",
+        ("living-room",),
+    )
+    device = service.registry.get("living-room").device()
+    if protection == "override":
+        service.db.execute(
+            "INSERT INTO overrides VALUES(?,?,?,?,?,?)",
+            ("active", "living-room", 1, 50, "2099-01-01", "2026-01-01"),
+        )
+    elif protection == "base":
+        service.db.execute(
+            "UPDATE device_state SET base_image_id=1 WHERE device_id=?",
+            ("living-room",),
+        )
+    elif protection == "unsynced":
+        device = device.model_copy(
+            update={
+                "current_content": device.current_content.model_copy(
+                    update={"synced": False}
+                )
+            }
+        )
+    elif protection in ("unknown", "syncing"):
+        operation = submit(service)
+        service._start_write(operation)
+        service.update(operation, protection.upper())
+    else:
+        service.db.execute(
+            "UPDATE device_state SET previous_image_id=2 WHERE device_id=?",
+            ("living-room",),
+        )
+    service.clear_self_restore_reference("living-room", device)
+    assert service.state("living-room")["previous_image_id"] == (
+        2 if protection == "other_previous" else 1
+    )
 
 
 def test_offline(service):