#/bin/bash

#
# author: arian
# date: 2024-05-06
#
# purpose:
#   use this script on a keyboard shortcut to automatically
#   change your output device to the next one using 'pactl'
#
# usage:
#   ./pactl-next-output-dev.sh /path/to/log
#

#region run in debug if $DEBUG
[ "$DEBUG" = 'true' ] && set -x
#endregion

#region globals
CYAN='\e[0;36m'
PURPLE='\e[0;35m'
NORMAL='\e[0m'
LOGFILE=${1:-'/var/log/arian/pactl-next-output-dev.sh.log'}
LOGDIR="$(dirname "${LOGFILE}")"
#endregion

#region functions
function log() {
  # logs strings to both the terminal and a file
  # usage: log [1-3] 'String'
  #   1 => INFORMATION
  #   2 => ERROR
  #   3 => DEBUG

  case $1 in
    1)
      msg_type="INFORMATION"
      ;;

    2)
      msg_type="ERROR"
      ;;

    3)
      msg_type="DEBUG"
      ;;

    *)
      echo "Wrong input; exiting"
      exit 1
  esac

  msg="[${PURPLE}$(date -Ins)${NORMAL}] [${CYAN}${msg_type}${NORMAL}]:  $2"
  # tee command from https://unix.stackexchange.com/questions/694671/leave-color-in-stdout-but-remove-from-tee
  # (omits coloring in logfile)
  echo -e "${msg}" | tee >(sed $'s/\033[[][^A-Za-z]*[A-Za-z]//g' >> ${LOGFILE})
}
#endregion

#region main
[ -d "${LOGDIR}" ] || mkdir -p "${LOGDIR}"

ALL_SINKS=($(pactl list short sinks | awk '{ print $2 }'))
CURR_SINK=$(pactl get-default-sink)
CURR_INDEX=-1

log 1 "Using current sink [${CURR_SINK}]"

for i in "${!ALL_SINKS[@]}"; do
  if [[ "${ALL_SINKS[$i]}" = "${CURR_SINK}" ]]; then
    CURR_INDEX="$i"
  fi
done

NEXT_INDEX=$(($((CURR_INDEX + 1))%(${#ALL_SINKS[@]})))

NEXT_SINK="${ALL_SINKS[$NEXT_INDEX]}"
log 1 "Switching to sink [${NEXT_SINK}]"
pactl set-default-sink "${ALL_SINKS[$NEXT_INDEX]}"

#endregion