/* ----------------------------------------------------------------------------

 Question Server question file merger
 GitLab: <https://gitlab.com/MrFry/mrfrys-node-server>

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program. If not, see <https://www.gnu.org/licenses/>.

 ------------------------------------------------------------------------- */

// TODO: handle flags
// join json datas, or raw datas
// or something else

var classes = require('./question-classes/classes.js')
var utils = require('./utils.js')

Main()

function Main () {
  console.clear()
  const params = GetParams()
  console.log(params)
  var dbs = []

  for (var i = 0; i < params.length; i++) {
    PrintLN()
    console.log(params[i] + ': ')
    try {
      dbs.push(ParseJSONData(utils.ReadFile(params[i])))
      console.log('JSON data added')
    } catch (e) {
      console.log(e)
      console.log('Trying with old format...')
      dbs.push(ReadData(utils.ReadFile(params[i])).result)
    }
  }
  PrintLN()

  dbs.forEach((item) => {
    PrintDB(item)
  })

  var olds = []
  if (dbs.length === 1) {
    for (let i = 0; i < dbs[0].length; i++) { olds.push(dbs[0].Subjects[i].length) }
  }

  console.log('Parsed data count: ' + dbs.length)
  PrintLN()

  console.log('Merging databases...')
  var db = MergeDatabases(dbs)

  console.log('Removing duplicates...')
  var r = RemoveDuplicates(db)

  console.log('RESULT:')
  PrintDB(r, olds)

  utils.WriteFile(JSON.stringify(r), 'newData')
  console.log('File written!')
}

function PrintLN () {
  console.log('------------------------------------------------------')
}

function PrintDB (r, olds) {
  console.log('Data subject count: ' + r.length)
  var maxLength = 0
  for (let i = 0; i < r.length; i++) {
    if (maxLength < r.Subjects[i].Name.length) { maxLength = r.Subjects[i].Name.length }
  }

  let qcount = 0

  for (let i = 0; i < r.length; i++) {
    let line = i
    if (line < 10) { line += ' ' }

    line += ': '
    var currLength = line.length + maxLength + 4
    line += r.Subjects[i].Name

    while (line.length < currLength) {
      if (i % 4 === 0) { line += '.' } else { line += ' ' }
    }

    if (olds && olds.length > 0) {
      // TODO: check if correct row! should be now, but well...
      if (olds[i] < 10) { line += ' ' }
      if (olds[i] < 100) { line += ' ' }

      line += olds[i]
      line += ' -> '
    }

    if (r.Subjects[i].length < 10) { line += ' ' }
    if (r.Subjects[i].length < 100) { line += ' ' }

    line += r.Subjects[i].length
    qcount += r.Subjects[i].length

    line += ' db'

    console.log(line)
  }

  console.log('Total questions: ' + qcount)

  PrintLN()
}

function GetParams () {
  return process.argv.splice(2)
}

function ParseJSONData (data) {
  var d = JSON.parse(data)
  var r = new classes.QuestionDB((x) => true, (x, y) => console.log(x, y))
  var rt = []

  for (var i = 0; i < d.Subjects.length; i++) {
    let s = new classes.Subject(d.Subjects[i].Name)
    var j = 0
    for (j = 0; j < d.Subjects[i].Questions.length; j++) {
      var currQ = d.Subjects[i].Questions[j]
      s.AddQuestion(new classes.Question(currQ.Q, currQ.A, currQ.I))
    }
    rt.push({
      name: d.Subjects[i].Name,
      count: j
    })
    r.AddSubject(s)
  }
  return r
}

function MergeDatabases (dbs) {
  var db = new classes.QuestionDB((x) => true, (x, y) => console.log(x, y))
  for (var i = 0; i < dbs.length; i++) {
    for (var j = 0; j < dbs[i].length; j++) { db.AddSubject(dbs[i].Subjects[j]) }
  }
  return db
}

/*
 * Returns a question database from the given data.
 * Parameter should be raw read file in string with "\n"-s
 * TODO: ??? -s are not listed as errors, tho works correctly
 * */
function ReadData (data) {
  const d = data.split('\n')
  const r = new classes.QuestionDB((x) => true, (x, y) => console.log(x, y))
  var logs = []
  var currSubj = '' // the current subjects name
  var ExpectedIdentifier = ['+', '?']
  let currQuestion = new classes.Question()

  var i = -1
  while (i < d.length) {
    let currIdentifier
    let skipped = 0
    do {
      if (skipped >= 1) { logs.push(i + ': ' + d[i]) }
      i++
      if (i >= d.length) {
        if (currQuestion.IsComplete()) { r.AddQuestion(currSubj, currQuestion) }
        return {
          result: r,
          logs: logs
        }
      }
      currIdentifier = d[i][0]
      skipped++
    } while (!ExpectedIdentifier.includes(currIdentifier) && i < d.length)

    let currData = d[i].substring(1).trim()

    if (currIdentifier === '+') {
      if (currQuestion.IsComplete()) { r.AddQuestion(currSubj, currQuestion) }
      currQuestion = new classes.Question()
      currSubj = currData
      ExpectedIdentifier = ['?']
      continue
    }

    if (currIdentifier === '?') {
      if (currQuestion.IsComplete()) {
        r.AddQuestion(currSubj, currQuestion)
        currQuestion = new classes.Question()
      }
      // overwriting is allowed here, bcus:
      // ?????!>
      currQuestion.Q = currData
      ExpectedIdentifier = ['!', '?']
      continue
    }

    if (currIdentifier === '!') {
      // if dont have question continue
      if (!currQuestion.HasQuestion()) { throw new Error('No question! (A)') }
      // dont allow overwriting
      // ?!!!!
      if (!currQuestion.HasAnswer()) {
        currData = currData.replace('A helyes válaszok: ', '')
        currData = currData.replace('A helyes válasz: ', '')

        currQuestion.A = currData
      }
      ExpectedIdentifier = ['?', '>', '+']
      continue
    }

    if (currIdentifier === '>') {
      // if dont have question or answer continue
      if (!currQuestion.HasQuestion()) { throw new Error('No question! (I)') }
      if (!currQuestion.HasAnswer()) { throw new Error('No asnwer! (I)') }
      // dont allow overwriting
      // ?!>>>
      if (!currQuestion.HasImage()) {
        try {
          currQuestion.I = JSON.parse(currData)
        } catch (e) {
          currQuestion.I = currData.split(',')
        }
      }
      ExpectedIdentifier = ['?', '+']
      continue
    }
  }

  return {
    result: r,
    logs: logs
  }
}

function RemoveDuplicates (dataObj) {
  for (var i = 0; i < dataObj.length; i++) { RemoveDuplFromSubject(dataObj.Subjects[i]) }
  return dataObj
}

function RemoveDuplFromSubject (subj) {
  var cp = subj.Questions
  subj.Questions = []
  for (var i = 0; i < cp.length; i++) {
    var j = 0
    // Only removes 100% match!
    while (j < subj.length && cp[i].Compare(subj.Questions[j]) !== 100) {
      j++
    }
    if (j < subj.length) {
      // console.log("----------------------------------------------------------");
      // console.log(cp[i].toString());
      // console.log("  VS  ");
      // console.log(subj.Questions[j].toString());
      // console.log(cp[i].Compare(subj.Questions[j]));
      // console.log(j);
      // console.log("removed:");
      // console.log(subj.Questions.splice(j, 1).toString());
      // console.log("----------------------------------------------------------");
    } else {
      subj.AddQuestion(cp[i])
    }
  }
}