aoc-lb-update-slack.js

const fs = require('fs')
const https = require('https')
const querystring = require('querystring')
const ord = (i) => {
  const j = i % 10,
    k = i % 100;
  if (j == 1 && k != 11) return i + "st";
  if (j == 2 && k != 12) return i + "nd";
  if (j == 3 && k != 13) return i + "rd";
  return i + "th";
}
const request = (options, postData) => new Promise((resolve, reject) => {
  if (postData) {
    var payload = querystring.stringify(postData)
    options.headers = {
      'Content-Type': 'application/x-www-form-urlencoded',
      'Content-Length': payload.length,
      ...options.headers
    }
  }
  const req = https.request(options, (response) => {
      let data = ''
      response.on('data', chunk => {
          data = data + chunk.toString();
      })
      response.on('end', () => resolve(data))
  })
  req.on('error', (error) => reject(error))
  if (postData) req.write(payload)
  req.end();
})

const main = async () => {
  const config = require('./config.json')
  const now = new Date()
  console.log(now, 'fetching leaderboard')
  const lb = JSON.parse(await request({
    hostname: 'adventofcode.com',
    port: 443,
    path: `/${now.getFullYear()}/leaderboard/private/view/${config.leaderboardID}.json`,
    method: 'GET',
    headers: {
      'Cookie': `session=${config.session}`
    }
  }))
  const members = Object.keys(lb.members).map(id => {
    const {name, completion_day_level: days, local_score, stars} = lb.members[id]
    const solves = Array.apply(null, Array(now.getDate())).map((x,i)=> i+1).map(d => {
      const parts = Object.keys(days[d]||{}).map(x => parseInt(x))
      return  ['1','2'].map(p => {
        const t = (days[d]||{})[p]?.get_star_ts
        return t ? new Date(1000 * t) : t
      })
    })
    return {name, solves, local_score, stars}
  }).sort((a,b)=> b.local_score-a.local_score)
  if (!fs.existsSync('./cache.json')) {
    return fs.writeFileSync(`./cache.json`, JSON.stringify(members, null, 2))
  }
  const cache = require('./cache.json')
  const updates = members.flatMap((m, mi) => {
    const rank = mi + 1
    const mcache = cache.find(x => x.name == m.name)
    const oldrank = cache.findIndex(x => x.name == m.name) + 1
    if (!mcache) {
      return `*${m.name}* has joined the leaderboard with ${m.stars} star${m.stars != 1 ? 's':''}, which puts them in ${ord(rank)} place.`
    }
    const newSolves = m.solves
      .map((s,d) => ({
        name: m.name,
        day: d + 1,
        timestamps: s,
        rank: s.map((x,p) => {
            return [...members].sort((a,b) => a.solves[d][p] - b.solves[d][p]).findIndex(mm => mm.name == m.name)
          })
      }))
      .filter((s, d) => {
        return mcache.solves[d].filter(x => x).length != s.timestamps.filter(x => x).length
      })
      .map(s => {
        const place = rank == oldrank
          ? `They are still in *${ord(rank)}* place.`
          : `They moved from ${ord(oldrank)} place to *${ord(rank)}* place.`
        let puzzle = s.day
        let part = 1
        if (!s.timestamps[1]) {
          puzzle += ' part 1'
          part = 0
        }
        return `*${m.name}* finished day ${puzzle}! They were the *${ord(s.rank[part]+1)}* person to do so. ${place}`
      })
    return newSolves
  }).filter(x => x)
  console.log(updates.join('\n'))
  const response = request({
    hostname: 'hooks.slack.com',
    port: 443,
    path: config.webhookPath,
    method: 'POST',
  }, {"payload": `{\"channel\": \"${config.channel}\", \"text\": \"${updates.map((x,i,s) => (s.length > 1 ? "• ":"")+x).join('\n')}\"}`})
  fs.writeFileSync(`./cache.json`, JSON.stringify(members, null, 2))
}
main()
setInterval(main, 1000 * 60 * 15)