interactive semver target script

bump.sh

#!/bin/bash
# Portions of this script are Copyright (C) 2017 Ingo Hollmann - All Rights Reserved
# Permission to copy and modify is granted under the Creative Commons Attribution 4.0 license
# https://www.bughunter2k.de/blog/cursor-controlled-selectmenu-in-bash
# Last revised 2020-11-12 by Gifford Nolwland <[email protected]>

# Call this file as so: `./select.sh "${ARRAY[@]}"`
# per https://stackoverflow.com/a/36808100/2764290

ESC=$(printf "\e")
CURR=0

declare -a MENU=("$@")

draw_menu() {
    for i in "${MENU[@]}"; do
        if [[ ${MENU[$CURR]} == $i ]]; then
            tput setaf 2; echo " > $i"; tput sgr0
        else
            echo "   $i";
        fi
    done
}

clear_menu()  {
    for i in "${MENU[@]}"; do tput cuu1; done
    tput ed
}

# Draw initial menu
draw_menu
while read -rs -n1 key; do # 1 char (not delimiter), silent
    # empty echo simulates <enter> which loads the input into the variable (due to lack of automatic echo including new line from read -s)
    # see: https://www.tutorialkart.com/bash-shell-scripting/bash-read-username-and-password/
    # echo
    # echo $key
    if [[ "$key" == "" ]]; then break; fi # accept choice on enter or space
    # match input keys
    # see: https://stackoverflow.com/questions/10679188/casing-arrow-keys-in-bash/11759139
    if [[ "$key" == $ESC ]]; then # an escape sequence was pressed
        read -rs -n2 -t1 key; # read 2 more characters, silent. Abort if no characters read after 1 second (mac minimum)
        case "$key" in
            '[A'|'0A'|'[D'|'0D') # cursor up or left: previous item
                ((CURR > 0)) && ((CURR--))
            ;;
            '[B'|'0B'|'[C'|'0C') # cursor down or right: next item
                ((CURR < ${#MENU[@]}-1)) && ((CURR++))
            ;;
            $'[1~'|$'[H'|$'0H')  # home: first item
                ((CURR=0))
            ;;
            $'[4~'|$'[F'|$'0F')  # end: last item
                ((CURR=${#MENU[@]}-1))
            ;;
            *) # esc key pressed, abort
                clear_menu
                echo "Aborted!"
                exit 1
            ;;
        esac
    fi

    # Redraw menu
    clear_menu
    draw_menu
done

# echo "Selected item $CURR: [${MENU[$CURR]}] \"${MENU[$CURR]}\"";
# echo ${MENU[$CURR]} > /tmp/semver # send out
clear_menu
tput setaf 2; echo " > ${MENU[$CURR]}"; tput sgr0
echo # add a new line after final output

exit 0