add-to-path

#!/usr/bin/env bash
dir=`pwd`

function show_help {
  echo "Add a binary file to PATH"
  echo "This must be run from the directory where the binary exists"
  echo "Usage: $0 [options] [filename]"
  echo "Options:"
  echo -e "-h\tShow this help"
}

ask() {
    # https://djm.me/ask
    local prompt default reply

    while true; do

        if [ "${2:-}" = "Y" ]; then
            prompt="Y/n"
            default=Y
        elif [ "${2:-}" = "N" ]; then
            prompt="y/N"
            default=N
        else
            prompt="y/n"
            default=
        fi

        # Ask the question (not using "read -p" as it uses stderr not stdout)
        echo -n "$1 [$prompt] "

        # Read the answer (use /dev/tty in case stdin is redirected from somewhere else)
        read reply </dev/tty

        # Default?
        if [ -z "$reply" ]; then
            reply=$default
        fi

        # Check if the reply is valid
        case "$reply" in
            Y*|y*) return 0 ;;
            N*|n*) return 1 ;;
        esac

    done
}

if [ -n "$1" ]
then
    binary="$1"
else
    echo "ERROR: filename must be provided"
    show_help
    exit 1
fi

while getopts "hd" opt; do
    case "$opt" in
        h)
            show_help
            exit 0
            ;;
  esac
done

echo "Adding '$binary' to PATH..."

if ask "This will add $binary to PATH, continue?" Y
then
    echo "Adding '$binary' to PATH..."
    if [ -h "/usr/local/bin/$binary" ]
    then
        echo -e "\n************"
        eval "ls -al /usr/local/bin/$binary"
        if yes_no_question "$binary link already exists, remove it?"
        then
            echo "Deleting link /usr/local/bin/$binary..."
            eval "sudo rm /usr/local/bin/$binary"
        else
            echo "Exiting, no changes made..."
            exit 0
        fi
        echo -e "************\n"
    fi
    echo "Creating symlink /usr/bin/$binary..."
    eval "sudo ln -s $dir/$binary /usr/local/bin/$binary"
    eval "ls -al /usr/local/bin/$binary"
else
    echo "Cancelling..."
fi