index.js

const Discord = require("discord.js");
const core = require("@actions/core");

const AAU_ICON =
  "https://media-exp1.licdn.com/dms/image/C510BAQHgfIxjqWSSsQ/company-logo_200_200/0/1519855922416?e=2159024400&v=beta&t=_L2XLMCXeEzSX_c8oBMM_uuEK1kgfno7ViFJXD5BP6U";
const GITHUB_ICON = "https://avatars.githubusercontent.com/u/86346038?s=200&v=4";

try {
  const team = JSON.parse(core.getInput("team"));
  const scrumMasters = determineScrumMasters(team);
  const embed = buildEmbed(scrumMasters);

  postScrumMastersDiscord(embed);
} catch (error) {
  core.setFailed(error.message);
}

function determineScrumMasters(team) {
  if (team.length < 2) throw new Error("You need a larger team");

  const first = process.env.GITHUB_RUN_NUMBER % team.length;
  const second = Math.random() *  team.length - 1;
  const scrumMasterOne = team.splice(first, 1);

  if (team.length < 4) return scrumMasterOne;

  const scrumMasterTwo = team.splice(second, 1);

  return scrumMasterOne.concat(scrumMasterTwo);
}

function buildEmbed(scrumMasters) {
  const week = getWeekStartAndEnd();
  let result = new Discord.MessageEmbed()
    .setTitle("New Scrum Master(s)")
    .setDescription(`The scrum masters for ${week.start} to ${week.end}`)
    .setColor("#211a52")
    .setAuthor("AAU-Dat", AAU_ICON, "http://github.com/AAU-Dat")
    .setFooter("Generated by the scrummasters github action.")
    .addField("Scrum master", scrumMasters[0], true);

  if (scrumMasters.length > 1) {
    result.addField("Second Scrum Master", scrumMasters[1], true);
  }

  return result;
}

function postScrumMastersDiscord(embed) {
  const webhook = process.env.DISCORD_WEBHOOK;
  const { id, token } = breakWebhook(webhook);

  const webhookClient = new Discord.WebhookClient(id, token);

  webhookClient
    .send({
      username: "Github Action",
      avatarURL: GITHUB_ICON,
      embeds: [embed],
    })
    .catch(console.error);

  webhookClient.destroy();
}

function breakWebhook(webhook) {
  const array = webhook.split("/");
  const length = array.length;
  if (length < 3) throw new Error("Webhook probably misrepresented");
  if (array[array.length - 1] == "github") {
    return { id: array[length - 3], token: array[length - 2] };
  }
  return { id: array[length - 2], token: array[length - 1] };
}

function getWeekStartAndEnd(){
  const today = new Date();
  const weekend = new Date();
  weekend.setDate(weekend.getDate() + 6);
  const options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
  const todayString = today.toDateString();
  const weekendString = weekend.toDateString();
  
  return {start: todayString, end: weekendString}
}