FreeDATA/modem/modem.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Wed Dec 23 07:04:24 2020

@author: DJ2LS
"""

# pylint: disable=invalid-name, line-too-long, c-extension-no-member
# pylint: disable=import-outside-toplevel

import atexit
import ctypes
import queue
import threading
import time
import codec2
import numpy as np
import sounddevice as sd
import structlog
import tci
import cw
from queues import RIGCTLD_COMMAND_QUEUE
import audio
import demodulator

TESTMODE = False

class RF:
    """Class to encapsulate interactions between the audio device and codec2"""

    log = structlog.get_logger("RF")

    def __init__(self, config, event_manager, fft_queue, service_queue, states, radio_manager) -> None:
        self.config = config
        self.service_queue = service_queue
        self.states = states
        self.event_manager = event_manager
        self.radio = radio_manager
        self.sampler_avg = 0
        self.buffer_avg = 0

        # these are crc ids now
        self.audio_input_device = config['AUDIO']['input_device']
        self.audio_output_device = config['AUDIO']['output_device']

        self.tx_audio_level = config['AUDIO']['tx_audio_level']
        self.enable_audio_auto_tune = config['AUDIO']['enable_auto_tune']
        self.tx_delay = config['MODEM']['tx_delay']

        self.radiocontrol = config['RADIO']['control']
        self.rigctld_ip = config['RIGCTLD']['ip']
        self.rigctld_port = config['RIGCTLD']['port']

        self.states.setTransmitting(False)

        self.ptt_state = False
        self.radio_alc = 0.0

        self.tci_ip = config['TCI']['tci_ip']
        self.tci_port = config['TCI']['tci_port']


        self.AUDIO_SAMPLE_RATE = 48000
        self.MODEM_SAMPLE_RATE = codec2.api.FREEDV_FS_8000

        # 8192 Let's do some tests with very small chunks for TX
        self.AUDIO_FRAMES_PER_BUFFER_TX = 1200 if self.radiocontrol in ["tci"] else 2400 * 2
        # 8 * (self.AUDIO_SAMPLE_RATE/self.MODEM_SAMPLE_RATE) == 48
        self.AUDIO_CHANNELS = 1
        self.MODE = 0
        self.rms_counter = 0

        # Make sure our resampler will work
        assert (self.AUDIO_SAMPLE_RATE / self.MODEM_SAMPLE_RATE) == codec2.api.FDMDV_OS_48  # type: ignore

        self.audio_received_queue = queue.Queue()
        self.data_queue_received = queue.Queue()
        self.fft_queue = fft_queue

        self.demodulator = demodulator.Demodulator(self.config, 
                                            self.audio_received_queue, 
                                            self.data_queue_received,
                                            self.states,
                                            self.event_manager,
                                            self.fft_queue
                                                   )



    def tci_tx_callback(self, audio_48k) -> None:
        self.radio.set_ptt(True)
        self.event_manager.send_ptt_change(True)
        self.tci_module.push_audio(audio_48k)

    def start_modem(self):
        if TESTMODE:
            return True
        elif self.radiocontrol.lower() == "tci":
            if not self.init_tci():
                return False
        else:
            if not self.init_audio():
                raise RuntimeError("Unable to init audio devices")
            self.demodulator.start(self.sd_input_stream)
            atexit.register(self.sd_input_stream.stop)

        # Initialize codec2, rig control, and data threads
        self.init_codec2()

        return True

    def stop_modem(self):
        try:
            # let's stop the modem service
            self.service_queue.put("stop")
            # simulate audio class active state for reducing cli output
            # self.stream = lambda: None
            # self.stream.active = False
            # self.stream.stop

        except Exception:
            self.log.error("[MDM] Error stopping modem")

    def init_audio(self):
        self.log.info(f"[MDM] init: get audio devices", input_device=self.audio_input_device,
                      output_device=self.audio_output_device)
        try:
            result = audio.get_device_index_from_crc(self.audio_input_device, True)
            if result is None:
                raise ValueError("Invalid input device")
            else:
                in_dev_index, in_dev_name = result

            result = audio.get_device_index_from_crc(self.audio_output_device, False)
            if result is None:
                raise ValueError("Invalid output device")
            else:
                out_dev_index, out_dev_name = result

            self.log.info(f"[MDM] init: receiving audio from '{in_dev_name}'")
            self.log.info(f"[MDM] init: transmiting audio on '{out_dev_name}'")
            self.log.debug("[MDM] init: starting pyaudio callback and decoding threads")

            sd.default.samplerate = self.AUDIO_SAMPLE_RATE
            sd.default.device = (in_dev_index, out_dev_index)

            # init codec2 resampler
            self.resampler = codec2.resampler()

            # SoundDevice audio input stream
            self.sd_input_stream = sd.InputStream(
                channels=1,
                dtype="int16",
                callback=self.demodulator.sd_input_audio_callback,
                device=in_dev_index,
                samplerate=self.AUDIO_SAMPLE_RATE,
                blocksize=4800,
            )
            self.sd_input_stream.start()

            return True



        except Exception as audioerr:
            self.log.error("[MDM] init: starting pyaudio callback failed", e=audioerr)
            self.stop_modem()
            return False

    def init_tci(self):
        # placeholder area for processing audio via TCI
        # https://github.com/maksimus1210/TCI
        self.log.warning("[MDM] [TCI] Not yet fully implemented", ip=self.tci_ip, port=self.tci_port)

        # we are trying this by simulating an audio stream Object like with mkfifo
        class Object:
            """An object for simulating audio stream"""
            active = True

        self.stream = Object()

        # lets init TCI module
        self.tci_module = tci.TCICtrl(self.audio_received_queue)

        return True

    def audio_auto_tune(self):
        # enable / disable AUDIO TUNE Feature / ALC correction
        if self.enable_audio_auto_tune:
            if self.radio_alc == 0.0:
                self.tx_audio_level = self.tx_audio_level + 20
            elif 0.0 < self.radio_alc <= 0.1:
                print("0.0 < self.radio_alc <= 0.1")
                self.tx_audio_level = self.tx_audio_level + 2
                self.log.debug("[MDM] AUDIO TUNE", audio_level=str(self.tx_audio_level),
                               alc_level=str(self.radio_alc))
            elif 0.1 < self.radio_alc < 0.2:
                print("0.1 < self.radio_alc < 0.2")
                self.tx_audio_level = self.tx_audio_level
                self.log.debug("[MDM] AUDIO TUNE", audio_level=str(self.tx_audio_level),
                               alc_level=str(self.radio_alc))
            elif 0.2 < self.radio_alc < 0.99:
                print("0.2 < self.radio_alc < 0.99")
                self.tx_audio_level = self.tx_audio_level - 20
                self.log.debug("[MDM] AUDIO TUNE", audio_level=str(self.tx_audio_level),
                               alc_level=str(self.radio_alc))
            elif 1.0 >= self.radio_alc:
                print("1.0 >= self.radio_alc")
                self.tx_audio_level = self.tx_audio_level - 40
                self.log.debug("[MDM] AUDIO TUNE", audio_level=str(self.tx_audio_level),
                               alc_level=str(self.radio_alc))
            else:
                self.log.debug("[MDM] AUDIO TUNE", audio_level=str(self.tx_audio_level),
                               alc_level=str(self.radio_alc))

    def transmit(
            self, mode, repeats: int, repeat_delay: int, frames: bytearray
    ) -> bool:
        """

        Args:
          mode:
          repeats:
          repeat_delay:
          frames:

        """
        if TESTMODE:
            return


        self.demodulator.reset_data_sync()
        # get freedv instance by mode
        mode_transition = {
            codec2.FREEDV_MODE.signalling: self.freedv_datac13_tx,
            codec2.FREEDV_MODE.datac0: self.freedv_datac0_tx,
            codec2.FREEDV_MODE.datac1: self.freedv_datac1_tx,
            codec2.FREEDV_MODE.datac3: self.freedv_datac3_tx,
            codec2.FREEDV_MODE.datac4: self.freedv_datac4_tx,
            codec2.FREEDV_MODE.datac13: self.freedv_datac13_tx,
        }
        if mode in mode_transition:
            freedv = mode_transition[mode]
        else:
            print("wrong mode.................")
            print(mode)
            return False

        # Wait for some other thread that might be transmitting
        self.states.waitForTransmission()
        self.states.setTransmitting(True)
        #self.states.channel_busy_event.wait()


        start_of_transmission = time.time()

        # Open codec2 instance
        self.MODE = mode

        txbuffer = bytes()

        # Add empty data to handle ptt toggle time
        if self.tx_delay > 0:
            self.transmit_add_silence(txbuffer, self.tx_delay)

        self.log.debug(
            "[MDM] TRANSMIT", mode=self.MODE.name, delay=self.tx_delay
        )

        if not isinstance(frames, list): frames = [frames]
        for _ in range(repeats):

            # Create modulation for all frames in the list
            for frame in frames:

                txbuffer = self.transmit_add_preamble(txbuffer, freedv)
                txbuffer = self.transmit_create_frame(txbuffer, freedv, frame)
                txbuffer = self.transmit_add_postamble(txbuffer, freedv)

            # Add delay to end of frames
            self.transmit_add_silence(txbuffer, repeat_delay)

        # Re-sample back up to 48k (resampler works on np.int16)
        x = np.frombuffer(txbuffer, dtype=np.int16)

        self.audio_auto_tune()
        x = audio.set_audio_volume(x, self.tx_audio_level)

        if self.radiocontrol not in ["tci"]:
            txbuffer_out = self.resampler.resample8_to_48(x)
        else:
            txbuffer_out = x

        # transmit audio
        self.transmit_audio(txbuffer_out)

        self.radio.set_ptt(False)
        self.event_manager.send_ptt_change(False)
        self.states.setTransmitting(False)

        end_of_transmission = time.time()
        transmission_time = end_of_transmission - start_of_transmission
        self.log.debug("[MDM] ON AIR TIME", time=transmission_time)
        return True

    def transmit_add_preamble(self, buffer, freedv):
        
        # Init buffer for preample
        n_tx_preamble_modem_samples = codec2.api.freedv_get_n_tx_preamble_modem_samples(
            freedv
        )
        mod_out_preamble =  ctypes.create_string_buffer(n_tx_preamble_modem_samples * 2)

        # Write preamble to txbuffer
        codec2.api.freedv_rawdatapreambletx(freedv, mod_out_preamble)
        buffer += bytes(mod_out_preamble)
        return buffer

    def transmit_add_postamble(self, buffer, freedv):
        # Init buffer for postamble
        n_tx_postamble_modem_samples = (
            codec2.api.freedv_get_n_tx_postamble_modem_samples(freedv)
        )
        mod_out_postamble =  ctypes.create_string_buffer(
            n_tx_postamble_modem_samples * 2
        )
        # Write postamble to txbuffer
        codec2.api.freedv_rawdatapostambletx(freedv, mod_out_postamble)
        # Append postamble to txbuffer
        buffer += bytes(mod_out_postamble)
        return buffer

    def transmit_add_silence(self, buffer, duration):
        data_delay = int(self.MODEM_SAMPLE_RATE * (duration / 1000))  # type: ignore
        mod_out_silence = ctypes.create_string_buffer(data_delay * 2)
        buffer += bytes(mod_out_silence)
        return buffer

    def transmit_create_frame(self, txbuffer, freedv, frame):
        # Get number of bytes per frame for mode
        bytes_per_frame = int(codec2.api.freedv_get_bits_per_modem_frame(freedv) / 8)
        payload_bytes_per_frame = bytes_per_frame - 2

        # Init buffer for data
        n_tx_modem_samples = codec2.api.freedv_get_n_tx_modem_samples(freedv)
        mod_out = ctypes.create_string_buffer(n_tx_modem_samples * 2)

        # Create buffer for data
        # Use this if CRC16 checksum is required (DATAc1-3)
        buffer = bytearray(payload_bytes_per_frame)
        # Set buffersize to length of data which will be send
        buffer[: len(frame)] = frame  # type: ignore

        # Create crc for data frame -
        #   Use the crc function shipped with codec2
        #   to avoid CRC algorithm incompatibilities
        # Generate CRC16
        crc = ctypes.c_ushort(
            codec2.api.freedv_gen_crc16(bytes(buffer), payload_bytes_per_frame)
        )
        # Convert crc to 2-byte (16-bit) hex string
        crc = crc.value.to_bytes(2, byteorder="big")
        # Append CRC to data buffer
        buffer += crc

        assert (bytes_per_frame == len(buffer))
        data = (ctypes.c_ubyte * bytes_per_frame).from_buffer_copy(buffer)
        # modulate DATA and save it into mod_out pointer
        codec2.api.freedv_rawdatatx(freedv, mod_out, data)
        txbuffer += bytes(mod_out)
        return txbuffer

    def transmit_morse(self, repeats, repeat_delay, frames):
        self.states.waitForTransmission()
        self.states.setTransmitting(True)
        # if we're transmitting FreeDATA signals, reset channel busy state
        self.log.debug(
            "[MDM] TRANSMIT", mode="MORSE"
        )
        start_of_transmission = time.time()

        txbuffer_out = cw.MorseCodePlayer().text_to_signal("DJ2LS-1")

        self.transmit_audio(txbuffer_out)
        self.radio.set_ptt(False)
        self.event_manager.send_ptt_change(False)

        self.states.setTransmitting(False)

        end_of_transmission = time.time()
        transmission_time = end_of_transmission - start_of_transmission
        self.log.debug("[MDM] ON AIR TIME", time=transmission_time)

    def init_codec2(self):
        # Open codec2 instances

        # INIT TX MODES - here we need all modes. 
        self.freedv_datac0_tx = codec2.open_instance(codec2.FREEDV_MODE.datac0.value)
        self.freedv_datac1_tx = codec2.open_instance(codec2.FREEDV_MODE.datac1.value)
        self.freedv_datac3_tx = codec2.open_instance(codec2.FREEDV_MODE.datac3.value)
        self.freedv_datac4_tx = codec2.open_instance(codec2.FREEDV_MODE.datac4.value)
        self.freedv_datac13_tx = codec2.open_instance(codec2.FREEDV_MODE.datac13.value)


    # Low level modem audio transmit
    def transmit_audio(self, audio_48k) -> None:
        self.radio.set_ptt(True)
        self.event_manager.send_ptt_change(True)

        if self.radiocontrol in ["tci"]:
            self.tci_tx_callback(audio_48k)
            # we need to wait manually for tci processing
            self.tci_module.wait_until_transmitted(audio_48k)
        else:
            sd.play(audio_48k, blocksize=4096, blocking=True)
        return