pub fn current_data_chunk_remaining(&self) -> (u64, usize) {
        match self.state {
            DecryptReadState::BufferedData { pos } => (self.data_chunk_count, self.buffer.len() - pos),
            _ => (self.data_chunk_count, 0),
        }
    }
Get remaining bytes in the current data chunk

Returning (DataChunkCount, RemainingBytes)
crates/shadowsocks/src/relay/tcprelay/aead_2022.rs