hfp: Implement initiate SLC procedure for HFP-HF

examples/run_hfp_gateway.py

@@ -16,9 +16,11 @@
 # Imports
 # -----------------------------------------------------------------------------
 import asyncio
+import collections
 import sys
 import os
 import logging
+from typing import Union
 
 from bumble.colors import color
 
@@ -30,6 +32,7 @@ from bumble.core import (
     BT_RFCOMM_PROTOCOL_ID,
     BT_BR_EDR_TRANSPORT,
 )
+from bumble import rfcomm
 from bumble.rfcomm import Client
 from bumble.sdp import (
     Client as SDP_Client,
@@ -39,7 +42,64 @@ from bumble.sdp import (
     SDP_SERVICE_CLASS_ID_LIST_ATTRIBUTE_ID,
     SDP_BLUETOOTH_PROFILE_DESCRIPTOR_LIST_ATTRIBUTE_ID,
 )
-from bumble.hfp import HfpProtocol
+
+
+logger = logging.getLogger(__name__)
+
+
+# -----------------------------------------------------------------------------
+# Protocol Support
+# -----------------------------------------------------------------------------
+
+# -----------------------------------------------------------------------------
+class HfpProtocol:
+    dlc: rfcomm.DLC
+    buffer: str
+    lines: collections.deque
+    lines_available: asyncio.Event
+
+    def __init__(self, dlc: rfcomm.DLC) -> None:
+        self.dlc = dlc
+        self.buffer = ''
+        self.lines = collections.deque()
+        self.lines_available = asyncio.Event()
+
+        dlc.sink = self.feed
+
+    def feed(self, data: Union[bytes, str]) -> None:
+        # Convert the data to a string if needed
+        if isinstance(data, bytes):
+            data = data.decode('utf-8')
+
+        logger.debug(f'<<< Data received: {data}')
+
+        # Add to the buffer and look for lines
+        self.buffer += data
+        while (separator := self.buffer.find('\r')) >= 0:
+            line = self.buffer[:separator].strip()
+            self.buffer = self.buffer[separator + 1 :]
+            if len(line) > 0:
+                self.on_line(line)
+
+    def on_line(self, line: str) -> None:
+        self.lines.append(line)
+        self.lines_available.set()
+
+    def send_command_line(self, line: str) -> None:
+        logger.debug(color(f'>>> {line}', 'yellow'))
+        self.dlc.write(line + '\r')
+
+    def send_response_line(self, line: str) -> None:
+        logger.debug(color(f'>>> {line}', 'yellow'))
+        self.dlc.write('\r\n' + line + '\r\n')
+
+    async def next_line(self) -> str:
+        await self.lines_available.wait()
+        line = self.lines.popleft()
+        if not self.lines:
+            self.lines_available.clear()
+        logger.debug(color(f'<<< {line}', 'green'))
+        return line
 
 
 # -----------------------------------------------------------------------------