window.dateFormats = {
  data : 'YYYY-MM-DD',
  html : 'LL'
}

window.query = s => document.querySelector(s)
window.queryP = (e, s) => e.querySelector(s)
let currencies = null

const abacusDebugEl = query('#abacus-debug')
const abacusDebugConsoleEl = queryP(abacusDebugEl, '#abacus-debug_console')

function appendText (e, t) {
  console.info(e, t)
  const textNode = document.createTextNode(t)
  e.appendChild(textNode)

  const brNodes = [0,0].map(() => document.createElement('br'))
  brNodes.forEach(brNode => e.appendChild(brNode))
}

const keys = o => Object.keys(o)

window.log = function log (...messages) {    
  abacusDebugConsoleEl.style.visibility = 'visible'
  console.info(messages)
  return messages.forEach(m => appendText(abacusDebugConsoleEl, m))
}

const mapCurrenciesCache = { }
function mapCurrencies ({ date, rates }) {      
  if (mapCurrenciesCache[date])
    return mapCurrenciesCache[date]

    const results = keys(rates).map(countryCode => {
      const meta = currencies[countryCode]
      if (!meta)
        return

        return {
          countryCode,
          value : rates[countryCode],
          date,
          entity : meta.ENTITY,
          currency : meta.Currency,
          numericCode : meta['Numeric Code'],
          minorUnit : meta['Minor unit']
        }
        })

    return (mapCurrenciesCache[date] = results)
}

function fetchMoneyJSON (date) {
  const formattedDate = moment(date).format(window.dateFormats.data)
  console.info(formattedDate)

  return d3.csv('currency.csv', function (rr) {
    currencies = rr.reduce((o, r) => {
      const code = r['Alphabetic Code']
      code !== '' && (o[code] = r)
      return o
    }, { })

    // http://fixer.io/
    fetch(`https://api.fixer.io/${formattedDate}`)
      .then(r => r.json())
      .then(j => log(JSON.stringify(mapCurrencies(j), null, '  ')))
      .catch(r => log(r)) 
  })
}