Coverage for src/bluetooth_sig/gatt/descriptors/external_report_reference.py: 89%

1"""External Report Reference Descriptor implementation.""" 

2 

3from __future__ import annotations 

4 

5import msgspec 

6 

7from ..characteristics.utils import DataParser 

8from .base import BaseDescriptor 

9 

10 

11class ExternalReportReferenceData(msgspec.Struct, frozen=True, kw_only=True): 

12 """External Report Reference descriptor data.""" 

13 

14 external_report_id: int 

15 

16 

17class ExternalReportReferenceDescriptor(BaseDescriptor): 

18 """External Report Reference Descriptor (0x2907). 

19 

20 References an external report by ID. 

21 Used in HID (Human Interface Device) profiles. 

22 """ 

23 

24 def _has_structured_data(self) -> bool: 

25 return True 

26 

27 def _get_data_format(self) -> str: 

28 return "uint16" 

29 

30 def _parse_descriptor_value(self, data: bytes) -> ExternalReportReferenceData: 

31 """Parse External Report Reference value. 

32 

33 Args: 

34 data: Raw bytes (should be 2 bytes for uint16) 

35 

36 Returns: 

37 ExternalReportReferenceData with external report ID 

38 

39 Raises: 

40 ValueError: If data is not exactly 2 bytes 

41 """ 

42 if len(data) != 2: 

43 raise ValueError(f"External Report Reference data must be exactly 2 bytes, got {len(data)}") 

44 

45 external_report_id = DataParser.parse_int16(data, endian="little") 

46 

47 return ExternalReportReferenceData(external_report_id=external_report_id) 

48 

49 def get_external_report_id(self, data: bytes) -> int: 

50 """Get the external report ID.""" 

51 parsed = self._parse_descriptor_value(data) 

52 return parsed.external_report_id