Interactive app menu for zsh

app_menu_tmpl.zsh

#!/usr/bin/env zsh
# Interactive app menu for zsh.

# Define colors
YELLOW="\033[93m"
RESET="\033[0m"

# Function to execute App. A, B, and C
do_something_A() {
  echo "Doing something A..."
}
do_something_B() {
  echo "Doing something B..."
}
do_something_C() {
  echo "Doing something C..."
}

# Function to display the menu
display_menu() {
  cat <<"EOF"

MENU
----
  1) Do something A
  2) Do something B
  3) Do something C
  4) Quit
EOF
}

# Function to display help message
display_help() {
  cat <<EOF
Usage: $(basename "$0") [OPTIONS]
Options:
  --help    Show this help message and exit.
Menu Options:
  1) Do something A
  2) Do something B
  3) Do something C
  4) Quit
(Type 'exit' for an emergency break)
EOF
}

main() {
  # Handle command-line arguments
  if [[ "$1" == "--help" ]]; then
    display_help
    exit 0
  fi

  user_choice="" # Initialize choice variable

  # Trap to handle CTRL+C (SIGINT)
  trap "echo; echo 'Aborting...'; exit 0" SIGINT

  # Loop until user selects 4 (Quit)
  while [[ "$user_choice" != "4" ]]; do
    display_menu
    echo -n "${YELLOW}Enter your choice >> ${RESET}"
    read -r user_choice

    # Validate user input
    if [[ ! "$user_choice" =~ ^[1-4]$ ]]; then
      echo "Invalid choice. Please choose a number between 1 and 4."
      continue
    fi

    case "$user_choice" in
    1) do_something_A ;;
    2) do_something_B ;;
    3) do_something_C ;;
    4) echo "Exiting..." ;;
    *) echo "Unexpected input. Please try again." ;;
    esac
  done
}

# Execute main function with command-line arguments
main "$@"