import { isInRange } from '../lib/dateFilter'

const getDate = (value, precision) => {
  const d = new Date(value)

  let day = d.getUTCDate()
  let month = d.getUTCMonth() + 1
  const year = d.getUTCFullYear()

  if (precision === '2weeks') {
    day = day < 16 ? 1 : 16
  }

  if (day < 10) {
    day = `0${day}`
  }

  if (month < 10) {
    month = `0${month}`
  }

  if (precision === 'day') {
    return `${day}/${month}/${year}`
  }

  if (precision === '2weeks') {
    if (d.getUTCDate() < 16) {
      return `${month}/${year} s1-2`
    } else {
      return `${month}/${year} s3-4`
    }
  }

  return `${month}/${year}`
}

const compute = (transactions, precision, dateFrom, dateTo) => {
  const indexes = {}
  const values = {}
  const labels = []
  const bar = {
    label: 'Capital',
    borderColor: 'rgb(54, 162, 235)',
    backgroundColor: 'rgb(216, 234, 255)',
    fill: true,
    cubicInterpolationMode: 'monotone',
    data: [],
  }
  let lastDate = null

  transactions.forEach((transaction) => {
    let date = getDate(transaction.date, precision)
    let begin = !Object.hasOwn(indexes, date)

    if (begin) {
      indexes[date] = labels.length
      values[date] = lastDate !== null ? values[lastDate] : 0

      if (isInRange(transaction.date, dateFrom, dateTo)) {
        labels.push(date)
      }
    }

    lastDate = date
    values[date] += transaction.credit
    values[date] -= transaction.debit
  })

  labels.forEach((label) => {
    const value = values[label]
    bar.data.push(value)
  })

  const config = {
    labels: labels,
    datasets: [bar],
  }

  return config
}

export { compute }