buffer CTOS_UPDATE_DECK

main.py

@@ -72,13 +72,14 @@ CTOS_EXTERNAL_ADDRESS = 0x17
 CTOS_HS_TODUELIST = 0x20
 CTOS_HS_KICK = 0x24
 
+STOC_CHANGE_SIDE = 0x7
 STOC_ERROR_MSG = 0x02
 STOC_CHAT = 0x19
 STOC_JOIN_GAME = 0x12
 STOC_TYPE_CHANGE = 0x13
+STOC_DUEL_START = 0x15
 STOC_HS_PLAYER_ENTER = 0x20
 
-
 async def handle_client(reader: StreamReader, writer: StreamWriter):
     remote_reader: StreamReader = None
     remote_writer: StreamWriter = None
@@ -120,6 +121,7 @@ async def handle_client(reader: StreamReader, writer: StreamWriter):
 
     class State:
         established = False
+        changing_side = False
 
     state = State()
 
@@ -266,12 +268,18 @@ async def handle_client(reader: StreamReader, writer: StreamWriter):
 
         async def pipe(src: StreamReader, dst: StreamWriter, direction: Union['STOC', 'CTOS']):
             try:
+                buffered: bytes = None
                 while not src.at_eof():
                     header = await src.readexactly(3)
                     length = struct.unpack('<H', header[:2])[0]
                     packet_id = header[2]
                     logger.info(f"Received {direction} packet ID {packet_id} with length {length} for {player_descriptor}")
                     payload = await src.readexactly(length - 1)
+                    if direction == 'CTOS':
+                        if packet_id == CTOS_UPDATE_DECK and not state.changing_side:
+                            logger.info(f"Received CTOS_UPDATE_DECK for {player_descriptor}, but buffer it until the next packet")
+                            buffered = header + payload
+                            continue
                     if direction == 'STOC':
                         if packet_id == STOC_JOIN_GAME:
                             state.established = True
@@ -284,11 +292,18 @@ async def handle_client(reader: StreamReader, writer: StreamWriter):
                                 logger.warning(f"Received error message for {player_descriptor}: {msg} {code}")
                                 await close_connection()
                                 return
-                    dst.write(header)
-                    dst.write(payload)
-                    if not (direction == 'CTOS' and packet_id == CTOS_UPDATE_DECK):
-                        # no drain after CTOS_UPDATE_DECK, because it's expected to glue with CTOS_READY
-                        await dst.drain()
+                        if packet_id == STOC_CHANGE_SIDE:
+                            state.changing_side = True
+                            logger.info(f"Changing side for {player_descriptor}")
+                        if packet_id == STOC_DUEL_START and state.changing_side:
+                            state.changing_side = False
+                            logger.info(f"Side finished for {player_descriptor}")
+                    if buffered:
+                        logger.info(f"Sending buffered CTOS_UPDATE_DECK for {player_descriptor}")
+                        dst.write(buffered)
+                        buffered = None
+                    dst.write(header + payload)
+                    await dst.drain()
             except Exception as e:
                 logger.warning(f"Error in pipe {direction} for {player_descriptor}: {e}")
                 pass