server.js

"use strict";

/* =============================================
*                   Imports
================================================*/

/**
 * Dotenv Initial configuration.
 */
require("dotenv").config();

/**
 * APi keys and env variables for the Discord bot.
 */
const { DISCORD, PREFIX } = process.env;

/**
 * Time in milliseconds for the timeout cycle.
 * Right now is 30.000 or 30 secs
 */
const time = 30000;

if (!DISCORD) {
	console.error("Error: No DISCORD variable in enviroment.\n Perhaps you forgot to include it?");
	process.exit(1);
}

if (!PREFIX) {
	console.error("Error: No PREFIX variable in enviroment.\n I will use '!' as prefix, but you should set one.");
}

/**
 * Starts the web server.
 */
require("./imports/webserver");

/**
 * Util functions to use anywhere.
 */
const utilities = require("./imports/utilities");

/**
 * Reddit wrapper.
 */
const reddit = require("./imports/reddit");

/**
 * Discord wrapper. 
 */
const Discord = require("discord.js");

/**
 * Discord client for he bot.
 */
const client = new Discord.Client();

/**
 * When the discord bot is ready, it will print the timestamp and
 * set the bot activity on discord.
 */
client.on("ready", () => {
	console.log(`[${utilities.dateNow()}] bot ready! :D and logged in as: ${client.user.tag}!`);
	client.user.setActivity("Reddit", { type: "WATCHING" });
});

/* =============================================
*           bot "on events" handlers
================================================*/

/**
 * Message handler for the bot. At every message the bot recieves, it will use
 * this handler.
 */
client.on("message", msg => {
	//never interact with bots >:C
	if (msg.author.bot) return;
	if (msg.channel.type === "dm" || msg.channel.type === "group") {
		msg.channel.send("Sorry, I only work on server text channels 😢.");
	} else if(msg.channel.type === "text"){
		const msgArray = msg.content.split(" ");
		const cmd = msgArray[0];
		const args = msgArray.slice(1);

		const prefix = PREFIX ? PREFIX : "!";

		switch (cmd) {
			case `${prefix}ping`:
				ping(msg);
				break;
			case `${prefix}reddit`:
				redditPost(msg);
				break;
			case `${prefix}about`:
				aboutBot(msg);
				break;
			case `${prefix}help`:
			case `${prefix}h`:
				helpBot(msg, prefix);
				break;
			case `${prefix}reddit2`:
				redditPostByParameter(msg, args);
				break;
			case `${prefix}setup`:
				serverSetup(msg);
				break;
			case `${prefix}list`:
				listSubreddits(msg);
				break;
			case `${prefix}remove`:
				removeSubreddits(msg, args);
				break;
			case `${prefix}add`:
				addSubreddit(msg, args);
				break;
			default:
				if (IsACommand(cmd, prefix)) {
					console.log(`[${utilities.dateNow()}] command not found: ${cmd + args.toString()}`);
					msg.channel.send("I don't understand that command");
				}
				break;
		}
	}
});

/* =============================================
*                   Functions
================================================*/

/**
 * ping- pong!
 * @param {Message} msg Message object to the bot
 * @author by Camilo Zambrano
 */
function ping(msg) {
	msg.reply("pong");
}

/**
 * Replies to a message with basic information about the bot.
 * @param {Message} msg Message to reply with the bot information
 * @author by Camilo Zambrano
 */
function aboutBot(msg) {
	let aboutMsg = new Discord.RichEmbed()
		.setTitle("About:")
		.setDescription("Information about this bot! 🤖")
		.setColor("#3174e0")
		.setThumbnail(client.user.displayAvatarURL)
		.addField("Name of the bot: ", client.user.username)
		.addField("Created on: ", client.user.createdAt)
		.addField("Code: ", "https://github.com/cawolfkreo/discord-reddit-bot")
		.setFooter("The bot is happy you care about him 🤖👍");

	msg.reply(aboutMsg);
}

/**
 * Sends the help information, wich right now is the bot commands.
 * @param {Message} message the message to reply with the information
 * @param {String} prefix Bot prefix command
 * @author by Camilo Zambrano
 */
function helpBot(message, prefix) {
	let helpMsg = new Discord.RichEmbed()
		.setTitle("Help:")
		.setDescription("commands for the bot")
		.setColor("#3174e0")
		.setThumbnail(client.user.displayAvatarURL)
		.addField(`${prefix}ping`, "pong!")
		.addField(`${prefix}about`, "info about this bot.")
		.addField(`${prefix}help`, "This very message 😜.")
		.addField(`${prefix}reddit`, "still in Beta. Gets last hour top posts from r/me_irl (admin only).")
		.addField(`${prefix}reddit2 <subreddit>`, "still in Beta. Gets the top posts from the <subreddit> you supply (admin only).")
		.addField(`${prefix}setup`, "still in Beta. Starts bot configuration dialog (admin only).")
		.setFooter("The bot wishes you to enjoy using his commands 🤖👍");

	message.channel.send(helpMsg);
}

/**
 * replies to the message with the me_irl subreddit top posts from the last hour
 * @param {Message} msg Message object to the bot
 * @author by Yesid Bejarano
 */
function redditPost(msg) {
	reddit.getTopPosts("me_irl")
		.then(res => asyncPosts(msg, res))
		.catch(error => {
			console.log(`[${utilities.dateNow()}] Error: ${error}`);
		});
}

/**
 * Get The top posts from the subreddit given
 * @param {Message} msg 
 * @param {Array<String>} args 
 * @author by Yesid Bejarano
 */
function redditPostByParameter(msg, args) {
	let args2 = args[0];
	reddit.getTopPosts(args2)
		.then(res => asyncPosts(msg, res))
		.catch(error => {
			console.log(`[${utilities.dateNow()}] Error: ${error}`);
		});
}

/**
 * replies a message with the configuration information and commands for the server 
 * @param {Message} msg the message to repy with the setup info
 */
function serverSetup(msg) {
	msg.channel.send("Under development.");
}

/**
 * Replies a message with the list of subreddits the server has
 * @param {Message} msg the message to reply with the list of subscribed subreddits for the server
 */
function listSubreddits(msg) {
	msg.channel.send("Under development.");
}

/**
 * Removes the subreddits the message's server has, based on the order of the list of
 * commands.
 * @param {Message} msg the message that called this command
 * @param {Array<String>} args the index of the subs to remove ["1","2",...]
 */
function removeSubreddits(msg, args) {
	args[0] += "lel";
	msg.channel.send("Under development.");
}

/**
 * Tries to add a public subreddit to the list the server has, if the server already have 5 subs
 * or the subreddit name does not exist or is a private sub, it will reply the message with the 
 * reasons why it couldn't add said subreddit.  
 * @param {Message} msg the message that called this command
 * @param {Array<String>} args the name of the subreddit to add to the list of subs the server has
 */
function addSubreddit(msg, args) {
	args[0] += "lel";
	msg.channel.send("Under development.");
}

/**
 * sends an array of reddit posts with some seconds in between them.
 * @param {Message} msg msg to get the channel for the message to send
 * @param {Array} posts reddit posts
 * @author by Yesid Bejarano
 */
function asyncPosts(msg, posts) {
	if (posts.length > 0) {
		msg.channel.send(posts[0].url);
		setTimeout(() => {
			const tail = posts.splice(1);
			asyncPosts(msg, tail);
		}, time);
	}
}

/**
 * This function tests if a message is a probable command for the bot or not.
 * @param {String} cmd The message to test if it is command or not
 * @param {String} prefix The prefix for commands
 * @author by Camilo Zambrano
 */
function IsACommand(cmd, prefix) {
	const begin = cmd.slice(0, prefix.length);

	return begin === prefix && cmd.charAt(0) !== " ";
}

/**
 * Discord login
 */
client.login(DISCORD);