isrightmonitorenabled

#!/usr/bin/env bash
# 
# File:
#   isrightmonitorenabled
# 
# Description:
#   Check if a right monitor (a monitor positioned to the right of the
#   leftmost monitor) is enabled.
# 
# Returns:
#   Monitor type (e.g. "DP", "HDMI", "VGA", "TV", "DVI1") if the monitor is
#   enabled
# 
# Exit codes:
#   0: is enabled
#   1: is not enabled
# 
# Options:
#   -o    also output offset/starting position of right monitor (returns string
#         in the format "<TYPE>,<OFFSET>")
# 
# Notes:
#   All monitors after the second will be ignored.
# 
#   The right monitor is considered the one with the lowest non-zero X offset.
#   The left monitor is always the first one with a zero X offset.
# 

while getopts :o OPT; do
  case "${OPT}" in
    o) OUTPUT_OFFSET=true;;
    \?)
      echo "isrightmonitorenabled: option \"${OPTARG}\" unknown" 1>&2
      exit 1
      ;;
  esac
done
shift $((OPTIND - 1))

IFS=$'\n'
xrandrMntrs=($(xrandr --query | grep ' connected'))
unset IFS

if [ "${#xrandrMntrs[@]}" -ge 2 ]; then
  for xrandrMntr in "${xrandrMntrs[@]}"; do
    vals=($(echo "${xrandrMntr}" | perl -ne \
        'm/([^ ]+) connected (?:primary )?[^+]+\+(\d+).*/; print "$1 $2"'))

    if [ "${#vals[@]}" -eq 2 ]; then
      mntrType="${vals[0]}"
      offst="${vals[1]}"

      if [[ "${offst}" -gt 0 && (-z "${lwstNonZeroOffst}" || "${offst}" -lt \
          "${lwstNonZeroOffst}") ]]; then
        RIGHT_MONITOR_TYPE="${vals[0]}"
        RIGHT_MONITOR_OFFST="${vals[1]}"
        lwstNonZeroOffst="${offst}"
      fi
    fi
  done

  if [ -n "${RIGHT_MONITOR_TYPE}" ]; then
    retStr="${RIGHT_MONITOR_TYPE}"
    if [ "${OUTPUT_OFFSET}" = 'true' ]; then
      retStr+=",${RIGHT_MONITOR_OFFST}"
    fi
    echo "${retStr}"
    exit 0
  else
    exit 1
  fi
else
  exit 1
fi