Files
bumble_fork/bumble/profiles/le_audio.py
2024-07-31 01:20:28 +08:00

84 lines
3.0 KiB
Python

# Copyright 2024 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# -----------------------------------------------------------------------------
# Imports
# -----------------------------------------------------------------------------
from __future__ import annotations
import dataclasses
import struct
from typing import List, Type
from typing_extensions import Self
from bumble import utils
# -----------------------------------------------------------------------------
# Classes
# -----------------------------------------------------------------------------
@dataclasses.dataclass
class Metadata:
'''Bluetooth Assigned Numbers, Section 6.12.6 - Metadata LTV structures.
As Metadata fields may extend, and Spec doesn't forbid duplication, we don't parse
Metadata into a key-value style dataclass here. Rather, we encourage users to parse
again outside the lib.
'''
class Tag(utils.OpenIntEnum):
# fmt: off
PREFERRED_AUDIO_CONTEXTS = 0x01
STREAMING_AUDIO_CONTEXTS = 0x02
PROGRAM_INFO = 0x03
LANGUAGE = 0x04
CCID_LIST = 0x05
PARENTAL_RATING = 0x06
PROGRAM_INFO_URI = 0x07
AUDIO_ACTIVE_STATE = 0x08
BROADCAST_AUDIO_IMMEDIATE_RENDERING_FLAG = 0x09
ASSISTED_LISTENING_STREAM = 0x0A
BROADCAST_NAME = 0x0B
EXTENDED_METADATA = 0xFE
VENDOR_SPECIFIC = 0xFF
@dataclasses.dataclass
class Entry:
tag: Metadata.Tag
data: bytes
@classmethod
def from_bytes(cls: Type[Self], data: bytes) -> Self:
return cls(tag=Metadata.Tag(data[0]), data=data[1:])
def __bytes__(self) -> bytes:
return bytes([len(self.data) + 1, self.tag]) + self.data
entries: List[Entry] = dataclasses.field(default_factory=list)
@classmethod
def from_bytes(cls: Type[Self], data: bytes) -> Self:
entries = []
offset = 0
length = len(data)
while offset < length:
entry_length = data[offset]
offset += 1
entries.append(cls.Entry.from_bytes(data[offset : offset + entry_length]))
offset += entry_length
return cls(entries)
def __bytes__(self) -> bytes:
return b''.join([bytes(entry) for entry in self.entries])