getOptsLongArgs.sh

#!/bin/bash
: ${SHORT_OPTS:="h-:"} # The -: allows long flags ex --this-is-a-flag --thisflag --flag
: ${LONG_OPTS:="[flag]:[arg]:[flag-long][flag-longer-arg]:[help]"}

set -x
source $(dirname ${BASH_SOURCE[0]})/long_args

show_usage() {
            cat << EOF
This is a demonstration script showing how to use the import of long_args support for bash getopts.
If you want to use this source the file as it exports the long_args() function.
Inside of your while loop for getopts before your case statement call:
    long_args "\${!OPTIND}"
Inside of case statement:
    \${opt} (Name of flag / option ex: h or help if -h or --help is passed in.)
    \${OPTARG} (Value of the argument passed in for the flag if there is one.
        ex:
        -f somefile.txt
        --file somefile.txt
        Both of the above would have \${OPTARG} set to somefile.txt

You do need to define \${LONG_OPTS} to define what long flags can be used as well as weather
they have arguments or not. And you must have -: in your schema for the short_opts that your getopts call uses.
Syntax for \${LONG_OPTS}:
    [flag] or [flag]:
    [flag]  defines --flag as a flag that takes no argument.
    [flag-noarg] defines --flag-arg as a flag that takes no argument.
    [flag]: defines --flag as a flag that takes an argument.
    [flag-arg]: defines --flag-arg as a flag that takes an argument.
    ex:
        \${LONG_OPTS}="[help][flagwitharg]:[flagnoarg][another-flag-with-arg]:"
        The above defines 4 flags:
            --help (This takes no argument)
            --flagwitharg (This takes an argument)
            --flagnoarg (This take no argument)
            --another-flag-with-arg (This takes an argument)

When passing in flags short flags work to getopts spec. Long flags do with the exception that
a long flag must be by it self with no other flags touching it and the argument if there  is one has to have a " "
between it and the flag.

EOF
}

while  getopts "$SHORT_OPTS" opt; do
    [[ -z "${@}" ]] && break
    long_args "${!OPTIND}"

    case ${opt} in
        \?)
            echo $(tput setaf 1) Invalid Flag $(tput sgr0)
            exit 1
            ;;
        h | help) show_usage;;

        :)
            echo What happened ${FLAG_TYPE}${opt}${OPTARG}
            ;;
        *)
            echo $(tput setaf 2)  used ${FLAG_TYPE}${opt} ${OPTARG} $(tput sgr0)
            ;;
    esac
done
[[ -z "${@}" ]] && show_usage
exit 0