#!/bin/bash
# First thing to note is that this is a bash script. Your script seemed to be running something called bash.sh
# I have no idea what that was.

# Set up warning and error. Why NOT make error call warning. Also note that there is never a good reason to refer
# to $*. Instead, always use "$@". And the cost savings of using >&2 instead of 1>&2 is just not worth it.
warning() { echo "$@" 1>&2; }
# Also, let's not forget that simple commands can be stacked into one command line.
error() { warning "$@"; exit 1; }

# Here we set usage up so that we can die with a bit more elegance.
usage()
{
    warning "$@"
    cat <&2
Usage: $prog [--timeout val] [--default yes|no] prompt
EOF
    exit 1
}

#
# Usage: yesno OPTIONS QUESTION
#
#   Options:
#     --timeout N    Timeout if no input seen in N seconds.
#     --default ANS  Use ANS as the default answer on timeout or
#                    if an empty answer is provided.
#
# Exit status is the answer.

# One notion is to declare things to be of type int.
# Also, never do your own options parsing. It's really hard and why invent the wheel? 
yesno()
{
    local ans
    local -i ok=0
    local -i timeout=0
    local tv	# TimeoutVal
    local default
    local temp
    # BTW, NEVER give a variabel a one-letter name. It's hard to find them using any editor.

    temp=$(getopt -o :d:t:h --long default:,timeout:,help -n $prog -- "$@")
    eval set -- "$temp"        # The double quotes are key here.
    shopt -s nocasematch       # Hey, this is bash. Let's not make life harder for ourselves.
                               # None of this checking to see if it's equal to y or to Y.
    while true
    do
        case "$1" in
        -d | --default)
            # No need to shift 1 to then get the value and then shift again. Just ref "$2" and then shift 2.
            default="$2"
            [[ -z "$default" ]] && error 'Missing default value'
	    [[ "$default" != y  
           &&  "$default" != yes
	   &&  "$default" != n
	   &&  "$default" != no ]] && error "Illegal default answer: $default"
            shift 2
            ;;

        -t | --timeout)
            # Note that tv is a string but if we decide that it's safe to assign to an in var then we do it.
	    tv="$2"
            [[ -z "$tv" ]] && error 'Missing timeout value'
	    [[ "$tv" =~ ^[0-9][0-9]*$ ]] && timeout=$((tv)) || error "Illegal timeout value: $tv"
            shift 2
            ;;

	-h | --help)
	    usage "Here's what you need to do to run this"
	    ;;

        --)
            This is how e get out of the options processing game.
	    shift
            break
            ;;

	*)
	    usage "$1: Unknown option"
	    ;;
	    
        esac
    done
    # Now that we're done with the procopt then we can do the consistency checks.
    if (( timeout != 0 ))  &&  [[ -z "$default" ]]
    then
        error 'Non-zero timeout requires a default answer'
    fi

    (( $# == 0 )) && error 'Missing question'

    while (( ok == 0 ))
    do
        if (( timeout != 0 ))
	then
            if read -t $timeout -p "$@" ans
	    then
                # Turn off timeout if answer entered.
                timeout=0
                # No need for all this testing and then assigning stuff. Just do it.
                : ${ans:="$default"}
            else
                ans=$default
            fi
        else
            read -p "$@" ans
            : ${ans:=$default}
        fi

	[[ "$ans" = y  
	|| "$ans" = yes
        || "$ans" = n
        || "$ans" = no ]] && ok=1 || warning 'Valid answers are: yes y no n'
    done
    [[ "$ans" = y || "$ans" = yes ]]
}

prog=$0
# This is just so you can see that you don't need basename and dirname. This is bash, not sh.
fn=${0##*/}
noshext=${fn%.sh}
# Also, not that I'm testing yesno, not 'yesno' and not "yesno". Don't interpolate if you don't have to..
if [[ ${noshext} == yesno ]]
then
    yesno 'Test bad timeout value? ' && yesno --timeout none "Hello? "
    yesno 'Test timeout without default value? ' && yesno --timeout 10 'Hello? '
    yesno 'Test bad default value? ' && yesno --default none "Hello? "
    yesno 'Yes or no? ' && echo 'You answered yes' || echo 'You answered no'
    yesno --default yes 'Yes or no (default yes) ? ' && echo 'You answered yes' || echo "You answered no"
    yesno --default no 'Yes or no (default no) ? ' && echo 'You answered yes' || echo 'You answered no'
    yesno --timeout 5 --default no 'Yes or no (timeout 5, default no) ? ' && echo 'You answered yes' || echo 'You answered no'
    yesno --timeout 5 --default yes 'Yes or no (timeout 5, default yes) ? ' && echo 'You answered yes' || echo 'You answered no'
fi