var fs = require('fs')
var XLSX = require('xlsx')

var content

function convertData () {
  var workbook = XLSX.readFile('cache/data.xlsx')
  var worksheet = workbook.Sheets.Sheet1

  content = XLSX.utils.sheet_to_json(worksheet)

  console.log('Data Converted to JSON')

  cleanData()
}

// Get rid of the lunches, keynotes, help desks, etc.
function cleanData () {
  let i
  for (i = 0; i < content.length; i++) {
    if (content[i]) {
      var sessionTags = content[i]['Session Tags']

      if (!sessionTags) {
        delete content[i]
      } else {
        var splitTags = content[i]['Session Tags'].split(',')
        var joinedTags = splitTags.join(', ')
        content[i]['Session Tags'] = joinedTags
      }
    }
  }
  console.log('Blank Session Tags Removed')

  fixDates()
}

function fixDates () {
  let i
  for (i = 0; i < content.length; i++) {
    if (content[i]) {
      var startDate = content[i]['Start Date/Time']
      var endDate = content[i]['End Date/Time']

      content[i]['Start Date/Time'] = getJsDateFromExcel(startDate)
      content[i]['End Date/Time'] = getJsDateFromExcel(endDate)
    }
  }

  console.log('Dates Fixed')

  fixNames()
}

String.prototype.InsertAt = function (CharToInsert, Position) {
  return this.slice(0, Position) + CharToInsert + this.slice(Position)
}

function splitNames (speakers) {
  const splitSpeakers = speakers.split(',')
  return splitSpeakers
}

function addSpace (speaker) {
  let i
  const matchIndexes = []

  for (i = 0; i < speaker.length; i++) {
    if (speaker.charAt(i).match(/[A-Z]/g)) {
      matchIndexes.push(i)
    }
  }

  if (speaker === 'KennyO\'Dell') {
    return 'Kenny O\'Dell'
  }

  // Skip the first capital letter, insert at the next one
  return speaker.InsertAt(' ', matchIndexes[1])
}

function fixNames () {
  let i
  for (i = 0; i < content.length; i++) {
    if (content[i]) {
      if (content[i]['Speaker Code']) {
        var speakerNames = content[i]['Speaker Code']
        // Are there more than one speaker?
        if (speakerNames.indexOf(',') === -1) {
          // If not, just add a space to the single name
          var fixedSpeaker = addSpace(speakerNames)
          content[i]['Speaker Code'] = fixedSpeaker
        } else {
          // Otherwise split the list up so we can add spaces to each name.
          var splitSpeakers = splitNames(speakerNames)
          var splitFixedSpeakers = []
          for (var index in splitSpeakers) {
            splitFixedSpeakers.push(addSpace(splitSpeakers[index]))
          }
          var fixedSpeakers = splitFixedSpeakers.join(', ')
          content[i]['Speaker Code'] = fixedSpeakers
        }
      }
    }
  }
  console.log('Names Fixed')

  splitData()
}

function splitData () {
  let i
  var sessions = []
  var learningLabs = []

  // Iterate over entire Dataset, seperate out Sessions & Learning Labs
  for (i = 0; i < content.length; i++) {
    if (content[i]) {
      if (content[i].Category === 'Conference Sessions') {
        sessions.push(content[i])
      } else if (content[i].Category === 'Learning Labs') {
        learningLabs.push(content[i])
      }
    }
  }

  // Write Sessions to File
  fs.writeFile('cache/sessions.json', JSON.stringify(sessions), 'utf8', function (err) {
    if (err) {
      return console.log(err)
    }
    console.log('Sessions File Written')
  })

  // Write Learning Labs to File
  fs.writeFile('cache/learninglabs.json', JSON.stringify(learningLabs), 'utf8', function (err) {
    if (err) {
      return console.log(err)
    }
    console.log('Learning Labs File Written')
  })
}

// https://gist.github.com/christopherscott/2782634
function getJsDateFromExcel (serialDate) {
  return new Date(-2209075200000 + (serialDate - (serialDate < 61 ? 0 : 1)) * 86400000)
}

module.exports = convertData

convertData()