#!/bin/bash

#set -ex

if [[ ! -f ${1} ]]; then
  printf "Error file ${1} not found\n"
  exit 1
fi

exec 3< ${1}
while IFS= read -u 3 LINE; do
  PROMPT="${LINE%%=*}"
  CVALUE="${LINE#*=}"
  if [[ -n $PROMPT ]]; then
    read -e -p "${PROMPT}=" -i "${CVALUE}" NVALUE
    if [[ $CVALUE = $NVALUE ]]; then
      printf "Unchanged\n"
    else
      printf "'${CVALUE}' > '${NVALUE}'\n"
      sed -Ei "s:${PROMPT}=${CVALUE}:${PROMPT}=${NVALUE}:" ${1}
    fi
  fi
done 

set +ex