const readlineSync = require('readline-sync');

const categories = {
  'ranking' : 0,
  'year' : 1,
  'album': 2,
  'artist': 3,
  'genre': 4
};
const possibleCats = [['year', 'album'],['album', 'year'],['album', 'artist'],['album','genre'],['artist','album']];

const gameState = {
  user:'', score:0, questionsAnswered: 0, questions: 5
  };

function pick4FromCat(category){
  const choices = [];
  const artists = new Set();
  let currentItem = '';
  while (choices.length < 4){
    currentItem = data[Math.floor(Math.random()*data.length)];
    if (!artists.has(currentItem[categories[category]])) {
      artists.add(currentItem[categories[category]]);
      choices.push(currentItem);
    }
  }
  return choices;
}


function askQuestionAbout(cat1, cat2){
  const catIndex1 = categories[cat1];
  const catIndex2 = categories[cat2];
  const choices = pick4FromCat(cat1);
  const answerIndex = Math.floor(Math.random()*4);
  let correctAnswer;
  correctAnswer = choices[answerIndex];
  let question;

  if(cat1 === 'year' && cat2 === 'album'){
    question = `Which of the following years did ${correctAnswer[categories['artist']]} release the album, ${correctAnswer[catIndex2]}?`
  }
  if(cat1 === 'album'){
    if (cat2 === 'year') question =`Which of the following albums was released in ${correctAnswer[catIndex2]}?`
    if (cat2 === 'artist') question = `${correctAnswer[catIndex2]} created which of the following albums?`
    if (cat2 === 'genre') question = `Which of the following is a ${correctAnswer[catIndex2]} album?`
  }
  if(cat1 === 'artist'){
    if(cat2 === 'album') question =`The album ${correctAnswer[catIndex2]} was released by which of the following artists?`
  }
  let userAnswer = Number(readlineSync.question(
    `${question}
  1: ${choices[0][catIndex1]}
  2: ${choices[1][catIndex1]}
  3: ${choices[2][catIndex1]}
  4: ${choices[3][catIndex1]}\n `));

  while(isNaN(userAnswer) || userAnswer > 4 || userAnswer < 1){
    userAnswer = Number(readlineSync.question('\nplease enter a number between 1 and 4! \n'))
    }

  console.log(
    `\nYour answer was \n  ${userAnswer}: ${choices[userAnswer-1][catIndex1]}\n\nthe correct answer is \n  ${answerIndex+1}: ${correctAnswer[catIndex1]}\n`);
    updateState((userAnswer-1) === answerIndex);
}

function updateState(correct){
  gameState.questionsAnswered++
  if(correct){
    gameState.score++;
    console.log('Congrats! You were correct');
  }else{
    console.log('Ya missed this one. Best of luck on the next!')
  }
    console.log(`Current score: ${gameState.score}/${gameState.questionsAnswered}`);
    console.log(`${gameState.questions - gameState.questionsAnswered} questions remaining!`)
}

function playGame(){
  gameState.user = readlineSync.question('What is your name? \n')
  console.log(`Welcome to the quiz, ${gameState.user}!`)

  while(gameState.questionsAnswered < gameState.questions){
    askQuestionAbout(...possibleCats[gameState.questionsAnswered%possibleCats.length])
  }
  console.log('---------')
  console.log(`Congrats on making it through the quiz, ${gameState.user}! Was it hard?`)
  console.log(`final score:${gameState.score}/${gameState.questionsAnswered}` )
}