/**
 * Commonly-used functions for formatting text in badge labels. Includes
 * ordinal numbers, currency codes, star ratings, versions, etc.
 */
'use strict'

const moment = require('moment')
moment().format()

function starRating(rating) {
  const flooredRating = Math.floor(rating)
  let stars = ''
  while (stars.length < flooredRating) {
    stars += '★'
  }
  const decimal = rating - flooredRating
  if (decimal >= 0.875) {
    stars += '★'
  } else if (decimal >= 0.625) {
    stars += '¾'
  } else if (decimal >= 0.375) {
    stars += '½'
  } else if (decimal >= 0.125) {
    stars += '¼'
  }
  while (stars.length < 5) {
    stars += '☆'
  }
  return stars
}

// Convert ISO 4217 code to unicode string.
function currencyFromCode(code) {
  return (
    {
      CNY: '¥',
      EUR: '€',
      GBP: '₤',
      USD: '$',
    }[code] || code
  )
}

function ordinalNumber(n) {
  const s = ['ᵗʰ', 'ˢᵗ', 'ⁿᵈ', 'ʳᵈ'],
    v = n % 100
  return n + (s[(v - 20) % 10] || s[v] || s[0])
}

// Given a number, string with appropriate unit in the metric system, SI.
// Note: numbers beyond the peta- cannot be represented as integers in JS.
const metricPrefix = ['k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y']
const metricPower = metricPrefix.map((a, i) => Math.pow(1000, i + 1))
function metric(n) {
  for (let i = metricPrefix.length - 1; i >= 0; i--) {
    const limit = metricPower[i]
    if (n >= limit) {
      n = Math.round(n / limit)
      if (n < 1000) {
        return '' + n + metricPrefix[i]
      } else {
        return '1' + metricPrefix[i + 1]
      }
    }
  }
  return '' + n
}

// Remove the starting v in a string.
function omitv(version) {
  if (version.charCodeAt(0) === 118) {
    return version.slice(1)
  }
  return version
}

// Add a starting v to the version unless:
// - it does not start with a digit
// - it is a date (yyyy-mm-dd)
const ignoredVersionPatterns = /^[^0-9]|[0-9]{4}-[0-9]{2}-[0-9]{2}/
function addv(version) {
  version = '' + version
  if (version.startsWith('v') || ignoredVersionPatterns.test(version)) {
    return version
  } else {
    return `v${version}`
  }
}

function maybePluralize(singular, countable, plural) {
  plural = plural || `${singular}s`

  if (countable && countable.length === 1) {
    return singular
  } else {
    return plural
  }
}

function formatDate(d) {
  const date = moment(d)
  const dateString = date.calendar(null, {
    lastDay: '[yesterday]',
    sameDay: '[today]',
    lastWeek: '[last] dddd',
    sameElse: 'MMMM YYYY',
  })
  // Trim current year from date string
  return dateString.replace(` ${moment().year()}`, '').toLowerCase()
}

function renderTestResultMessage({
  passed,
  failed,
  skipped,
  total,
  passedLabel,
  failedLabel,
  skippedLabel,
  isCompact,
}) {
  const labels = { passedLabel, failedLabel, skippedLabel }
  if (total === 0) {
    return 'no tests'
  } else if (isCompact) {
    ;({ passedLabel = '✔', failedLabel = '✘', skippedLabel = '➟' } = labels)
    return [
      `${passedLabel} ${passed}`,
      failed > 0 && `${failedLabel} ${failed}`,
      skipped > 0 && `${skippedLabel} ${skipped}`,
    ]
      .filter(Boolean)
      .join(' | ')
  } else {
    ;({
      passedLabel = 'passed',
      failedLabel = 'failed',
      skippedLabel = 'skipped',
    } = labels)
    return [
      `${passed} ${passedLabel}`,
      failed > 0 && `${failed} ${failedLabel}`,
      skipped > 0 && `${skipped} ${skippedLabel}`,
    ]
      .filter(Boolean)
      .join(', ')
  }
}

function renderTestResultBadge({
  passed,
  failed,
  skipped,
  total,
  passedLabel,
  failedLabel,
  skippedLabel,
  isCompact,
}) {
  const message = renderTestResultMessage({
    passed,
    failed,
    skipped,
    total,
    passedLabel,
    failedLabel,
    skippedLabel,
    isCompact,
  })

  let color
  if (total === 0) {
    color = 'yellow'
  } else if (failed > 0) {
    color = 'red'
  } else if (skipped > 0 && passed > 0) {
    color = 'green'
  } else if (skipped > 0) {
    color = 'yellow'
  } else {
    color = 'brightgreen'
  }

  return { message, color }
}

module.exports = {
  starRating,
  currencyFromCode,
  ordinalNumber,
  metric,
  omitv,
  addv,
  maybePluralize,
  formatDate,
  renderTestResultMessage,
  renderTestResultBadge,
}