app.js

const chalk = require('chalk');
const yargs = require('yargs');
const fs = require('fs');

const notes = require('./notes.js');

//Customize yargs version
yargs.version(chalk.blue('Notes version: 1.1.0'))

//Command handlers
const addHandler = (argv) =>  notes.addNote(argv.title, argv.body);

const removeNote = (argv) => notes.removeNote(argv.title);

const listNotes =  () => notes.listNotes();

const readNote = (argv) => notes.readNote(argv.title);

//Command builders
const noBuilder = {}
//add
const addBuilder = {
    title: {
        describe: 'Note title',
        demandOption: true,
        type: 'string'
    },
    body: {
        describe: 'Note body',
        demandOption: true,
        type: 'string'
    }
};
//remove
const removeBuilder = {
    title: {
        describe: 'Note title',
        demandOption: true,
        type: 'string'
    }
};
//read
const readBuilder = {
    title: {
        describe: 'Note title',
        demandOption: true,
        type: 'string'
    }
};

//Commands list
const commands = [
    { action: 'add', description: 'Add a new note', builder: addBuilder, handler: addHandler },
    { action: 'remove', description: 'Remove a note', builder: removeBuilder, handler: removeNote },
    { action: 'list', description: 'List all notes', builder: noBuilder, handler: listNotes },
    { action: 'read', description: 'Read a note', builder: readBuilder, handler: readNote }
];

//Generate all commands from the list
commands.forEach(command => yargs.command(command.action, chalk.blue(command.description), command.builder, command.handler))

yargs.parse()