b5-calculate-score/lib/reduce-factors.js

micro webservice that evaluates bigfive questions

const calculateResultDefault = (score, count) => {
  const average = score / count
  let result = 'neutral'
  if (average > 3) {
    result = 'high'
  } else if (average < 3) {
    result = 'low'
  }
  return result
}

module.exports = options => {
  const calculateResult = options.calculateResult || calculateResultDefault

  const reduceFactors = (a, b) => {
    if (!a[b.domain]) {
      a[b.domain] = {score: 0, count: 0, result: 'neutral', facet: {}}
    }

    a[b.domain].score += parseInt(b.score || 0, 10)
    a[b.domain].count += 1
    a[b.domain].result = calculateResult(a[b.domain].score, a[b.domain].count)

    if (b.facet) {
      if (!a[b.domain].facet[b.facet]) {
        a[b.domain].facet[b.facet] = {score: 0, count: 0, result: 'neutral'}
      }
      a[b.domain].facet[b.facet].score += parseInt(b.score || 0, 10)
      a[b.domain].facet[b.facet].count += 1
      a[b.domain].facet[b.facet].result = calculateResult(a[b.domain].facet[b.facet].score, a[b.domain].facet[b.facet].count)
    }

    return a
  }

  return options.answers.reduce(reduceFactors, {})
}