Simple todo list script in ruby

todo.rb

#!/bin/ruby

require 'base64'
require 'readline'
require "curses"

# setup readline for tab-completion and ncurse window
cmds = ["exit", "save"]
complete = proc {|str| cmds.grep(/^#{str}/); }
Readline.completion_proc = complete
Readline.completion_append_character = ''
Curses.init_screen
height, width = Curses.lines, Curses.cols
win = Curses::Window::new(height, width, 0, 0)
win.refresh

# get the todos from file
path = File.expand_path("~/.todo.mine")
todos = Base64.decode64(File.read(path)).split("\n") || Array.new

# main loop
loop do
  # show the todos
  win.clear
  todos.each_with_index {|todo, index| win.addstr "#{index+1}. #{todo}\n"}
  win.refresh

  # read input from user
  line = Readline.readline("-> ", true)

  # check for commands
  case
    when line == "exit"
      win.close
      exit 0
    when line == "save"
    File.write(path, Base64.encode64(todos.join("\n")))
    next
  end

  # add todo to list if not already in or del if already in
  if line.to_i >= 1 then todos = todos.reject{|e| e == todos[line.to_i-1]}
  else todos.append(line) unless line.strip.empty? end
end