#!/bin/bash
#
# Author  : Gaston Gonzalez
# Date    : 24 December 2024
# Purpose : Wrapper script for minimodem
#
# Preconditions:
# 1. DigiRig Lite is set in et-radio and connected

usage() {
  echo "usage: $(basename $0) <command> <file>"
  echo "  <command>"
  echo "    tx-file   - File to transmit"
  echo "    rx-file   - Save incoming transmition to file"
  echo ""
  echo "The baud rate can be set with the BAUD_RATE environment variable"
  echo "It defaults to 1200 if not specified."
  echo "BAUD_RATE=300 /et-minimodem tx-file /etc/motd"
}

if [ $# -ne 2 ]; then
  usage
  exit 1
fi

FILE=$2

# Allow users to override baud rate via an environment variable.
# For example: BAUD_RATE=300 /et-minimodem tx-file /etc/motd
if [ -z ${BAUD_RATE} ]; then
  BAUD_RATE=1200
fi

case $1 in
  tx-file)

    AUDIO_DEV=$(et-system-info et-audio)
    if [ "${AUDIO_DEV}" != "DigiRig Lite" ]; then
      et-log "Minimodem only supports the DigiRig Lite. You have a '$AUDIO_DEV'"
      exit 1
    fi

    AUDIO_CARD=$(et-system-info et-audio-card)
    if [ $? -ne 0 ]; then
      et-log "No audio device detected."
      exit 1
    fi

    ALSA_DEV="plughw:${AUDIO_CARD}"

    if [ ! -e ${FILE} ]; then
      et-log "File ${FILE} does not exist."
      exit
    fi

    cat ${FILE} | minimodem --tx --alsa=${ALSA_DEV} ${BAUD_RATE}
    ;;

  rx-file)
    echo "Not yet implemented"
    ;;
  *)
    echo "Invalid command."
    usage
    exit 1
  ;;
esac