Bash: Yes/No Confirm script - Advanced

yes_no_confirm.sh

#!/bin/bash
# Author: Nghia Le <[email protected]>
# Description:
#   - To make user confirm the privilege which they are using to run a bash script
#     by asking user if they're sure and wanted to run this bash script as current log-in user.

read -n 1 -p "Do you want to run this bash script as $(whoami)? Yes/[No]: " YES_NO
echo -e "\n"

if [ -z ${YES_NO} ] || [ ${YES_NO} = "No" ] ||  [ ${YES_NO} = "no" ] ||  [ ${YES_NO} = "N" ] ||  [ ${YES_NO} = "n" ]; then
    echo "You select No, then it is going to exit now... "
    sleep 1
    echo -e "\nGood bye now..!!!\n"
    sleep 1
    exit 1
elif [ ${YES_NO} = "Yes" ] ||  [ ${YES_NO} = "yes" ] ||  [ ${YES_NO} = "Y" ] ||  [ ${YES_NO} = "y" ]; then
    read -n 1 -p "Are you really sure? Yes/[No]: " YES_NO2
    echo -e "\n"
    if [ -z ${YES_NO2} ] || [ ${YES_NO2} = "No" ] ||  [ ${YES_NO2} = "no" ] ||  [ ${YES_NO2} = "N" ] ||  [ ${YES_NO2} = "n" ]; then
        echo "You select No, then it is going to exit now... "
        sleep 1
        echo -e "\nGood bye now..!!!\n"
        sleep 1
        exit 1
    elif [ ${YES_NO2} = "Yes" ] ||  [ ${YES_NO2} = "yes" ] ||  [ ${YES_NO2} = "Y" ] ||  [ ${YES_NO2} = "y" ]; then
        echo "Look likes you're pretty to to run bash script as $(whoami)..."
        sleep 2
        echo -e "\nHmmmm, hummm..."
        sleep 2
        echo -e "\nOkey, then it is going to run the bash script now... after 5 seconds"
        sleep 3
        echo -e "\n2 seconds now..."
        sleep 2
        echo -e "\nDeploying...\n"
    fi
fi