Bot Code Discord.js

const Discord = require("discord.js");
const bot = new Discord.Client();

const config = require("./config.json");

bot.on("ready", () => {
  console.log("I am ready!");
});

bot.on("guildMemberAdd", member => {
  let guild = member.guild;
  guild.defaultChannel.sendMessage(`Welcome ${member.user} to this server.`).catch(console.error);
});

bot.on("guildMemberRemove", member => {
  let guild = member.guild;
  guild.defaultChannel.sendMessage(`${member.user} left this server.`).catch(console.error);
});

bot.on("guildCreate", guild => {
  console.log(`New guild added : ${guild.name}, owned by ${guild.owner.user.username}`);
});

bot.on("presenceUpdate", (oldMember, newMember) => {
  let guild = newMember.guild;
  let playRole = guild.roles.find("name", "Playing Overwatch");
  if(!playRole) return;

  if(newMember.user.presence.game && newMember.user.presence.game.name === "Overwatch") {
    newMember.addRole(playRole).catch(console.error);
  } else if(!newMember.user.presence.game && newMember.roles.has(playRole.id)) {
    newMember.removeRole(playRole).catch(console.error);
  }
});

bot.on("message", message => {
  if (message.author.bot) return;
  if (!message.content.startsWith(config.prefix)) return;

  let command = message.content.split(" ")[0];
  command = command.slice(config.prefix.length);

  let args = message.content.split(" ").slice(1);

  if (command === "add") {
    let numArray = args.map(n=> parseInt(n));
    let total = numArray.reduce( (p, c) => p+c);

    message.channel.sendMessage(total).catch(console.error);
  }

  if (command === "say") {
    message.channel.sendMessage(args.join(" ")).catch(console.error);
  }

  if (command === "help") {
      message.channel.sendMessage("List of commands: add , say , help , ping , foo , kick , eval.")
  }

  if (command === "ping") {
    message.channel.sendMessage("Pong!").catch(console.error);
  } else

  if (command === "foo") {
    let modRole = message.guild.roles.find("name", "Mods");
    if(message.member.roles.has(modRole.id)) {
      message.channel.sendMessage("bar!").catch(console.error);
    } else {
      message.reply("You pleb, you don't have the permission to use this command.").catch(console.error);
    }
  }

  if (command === "kick") {
    let modRole = message.guild.roles.find("name", "Mods");
    if(!message.member.roles.has(modRole.id)) {
      return message.reply("You pleb, you don't have the permission to use this command.").catch(console.error);
    }
    if(message.mentions.users.size === 0) {
      return message.reply("Please mention a user to kick").catch(console.error);
    }
    let kickMember = message.guild.member(message.mentions.users.first());
    if(!kickMember) {
      return message.reply("That user does not seem valid");
    }
    if(!message.guild.member(bot.user).hasPermission("KICK_MEMBERS")) {
      return message.reply("I don't have the permissions (KICK_MEMBER) to do this.").catch(console.error);
    }
    kickMember.kick().then(member => {
      message.reply(`${member.user.username} was succesfully kicked.`).catch(console.error);
    }).catch(console.error)
  }

  if (command === "eval") {
    if(message.author.id !== "218433593741934592") return;
    try {
      var code = args.join(" ");
      var evaled = eval(code);

      if (typeof evaled !== "string")
        evaled = require("util").inspect(evaled);

      message.channel.sendCode("xl", clean(evaled));
    } catch(err) {
      message.channel.sendMessage(`\`ERROR\` \`\`\`xl\n${clean(err)}\n\`\`\``);
    }
  }

}); // END MESSAGE HANDLER

function clean(text) {
  if (typeof(text) === "string")
    return text.replace(/`/g, "`" + String.fromCharCode(8203)).replace(/@/g, "@" + String.fromCharCode(8203));
  else
      return text;
}

bot.login(config.token);