league-scheduler.js

/*
 * Expects a JSON array of teams in the same format as byeTeam
 */
const fs = require('fs');
const util = require('util');

var teamFile = 'teams.json';

const byeTeam = { coach: '', race: '', teamName: 'BYE' };

// Parse teams:
var teams;
try {
  teams = JSON.parse(fs.readFileSync(teamFile, 'utf8'));
}
catch (e) {
  console.log(util.format("Got error: %s\nDoes '%s' exist?", e.message, teamFile));
  return;
}

// Setup indexes:
if (teams.length % 2 != 0)
  teams.push("BYE");

var indexes = [];
for (var i = 0; i < teams.length; ++i)
  indexes.push(i);

// Randomise the indexes (a good old Fisher–Yates Shuffle):
var currentIndex = indexes.length, temporaryIndex, randomIndex;

while (0 !== currentIndex) {
  randomIndex = Math.floor(Math.random() * currentIndex);
  currentIndex -= 1;

  temporaryIndex = indexes[currentIndex];
  indexes[currentIndex] = indexes[randomIndex];
  indexes[randomIndex] = temporaryIndex;
}

// Schedule the league:
var top = indexes.slice(0, indexes.length / 2);
var bottom = indexes.slice(indexes.length / 2, indexes.length);
var weeks = indexes.length - 1;

var league = {
  teams: teams,
  schedule: []
}

for (var i = 0; i < weeks; ++i) {
  temporaryIndex = top.shift();
  bottom.push(top.pop());
  top.unshift(bottom.shift());
  top.unshift(temporaryIndex);

  var week = {day: i + 1, games:[]};
  for (var j = 0; j < top.length; ++j) {
    week.games.push( {a:top[j], b:bottom[j], played:false});
  }
  league.schedule.push(week)
}

fs.writeFileSync("schedule.json", JSON.stringify(league, null, " "), "utf8");

schedule-pretty-print.js

/*
 * Loads a schedule.json file output by league-scheduler.js and prints it in a
 * couple of useful formats.
 */

 var scheduleFile = 'schedule.json';
 var startDate = new Date("2016-01-31"); // ISO 8601: "YYYY-MM-DD"

 const fs = require('fs');
 const util = require('util');

 // Parse schedule:
 var schedule;
 try {
   schedule = JSON.parse(fs.readFileSync(scheduleFile, 'utf8'));
 }
 catch (e) {
   console.log( "Got error: {0}\nDoes {1} exist?".format(e.message, teamFile));
   return;
 }

 var teams = schedule.teams;
 schedule = schedule.schedule;

// Print the schedule:
var date = new Date(startDate);
var csv = fs.createWriteStream('schedule.csv');
var forum = fs.createWriteStream('schedule.forum');

schedule.forEach(function (day, dayIndex, dayArray) {
  csv.write(util.format("Day %d,%d/%d/%d,", day.day, date.getMonth() + 1, date.getDate(), date.getFullYear()))

  forum.write(util.format("Day %d:\n", day.day));

  day.games.forEach(function (game, gameIndex, gameArray) {
    csv.write(util.format("%s,vs,%s,", teams[game.a].teamName, teams[game.b].teamName));
    forum.write(util.format("%s [b]vs[/b] %s\n", teams[game.a].teamName, teams[game.b].teamName));
  });

  date.setDate(date.getDate() + 7);
  csv.write("\n");
  forum.write("\n\n");

});