voting-members.js

const fs = require('fs')
const assert = require('assert')
const process = require('process')

const files = fs.readdirSync('.').filter(x => x.endsWith('.csv'))
const text = files.map(f => fs.readFileSync(f).toString())

const events = [].concat(...text.map(content => content.split('\r\n').slice(6, -1).map(x => x.split(','))))

const EMAIL = 2
const NAME = 5
const CWID = 8

const cwid2email = {}
const email2cwid = {}

events.map(line => {
  if (line[CWID] === '""')
    return

  if (cwid2email[line[CWID]])
    assert(cwid2email[line[CWID]] == line[EMAIL])
  else
    cwid2email[line[CWID]] = line[EMAIL]
})

events.map(line => {
  if (line[EMAIL] === '""')
    return

  if (email2cwid[line[EMAIL]])
    assert(email2cwid[line[EMAIL]] == line[CWID])
  else
    email2cwid[line[EMAIL]] = line[CWID]
})

// console.log(cwid2email)
// console.log(email2cwid)

const attended = {}

events.forEach(line => {
  let id = line[CWID]
  if (id === '""') {
    id = email2cwid[line[EMAIL]]
  }
  if (id === '""') {
    if (line[EMAIL] !== '""')
      id = line[EMAIL]
    else {
      console.log('bad', line)
      return;
    }
  }

  if (attended[id])
    attended[id]++
  else
    attended[id] = 1;
})

const voters = Object.entries(attended).filter(([key, value]) => value >= files.length/2)
console.log(voters.map(([id, count]) => [cwid2email[id] || id, count]))