game.js

var buttonColours = ["red","blue","green","yellow"];
var gamePattern = [];
var userClickedPattern = [];

var started = false;

var level = 0;

$(document).keypress(function() {
  if (!started) {
    $("#level-title").text("Level " + level);
    nextSequence();
    started = true;
  }
});


$(".btn").on("click",function(){
    var userChosenColour = $(this).attr("id");
    userClickedPattern.push(userChosenColour);
    playSound(userChosenColour);
    animatePress(userChosenColour);
    checkAnswer(userClickedPattern.length-1);
})

function checkAnswer(currentLevel) {
    if (gamePattern[currentLevel] === userClickedPattern[currentLevel]) {
      console.log("success");
      if (userClickedPattern.length === gamePattern.length){
        setTimeout(function () {
          nextSequence();
        }, 1000);
      }

    } else {
        playSound("wrong");
        $("body").addClass("game-over");
        setTimeout(function(){
            $("body").removeClass("game-over");
        },200);
        $("#level-title").text("Game Over, Press Any Key to Restart");
        startOver();
    }

}


function nextSequence(){
    userClickedPattern = [];
    level++;
    $("#level-title").text("Level " + level);
    var n = Math.random()*4;
    var randomNumber = Math.floor(n);
    var randomChosenColor = buttonColours[randomNumber];
    gamePattern.push(randomChosenColor);

   $("#"+randomChosenColor).fadeIn(100).fadeOut(100).fadeIn(100);
   playSound(randomChosenColor);
}

function playSound(name){
    var audio = new Audio("sounds/" + name + ".mp3");
    audio.play();
}

function animatePress(currentColor){
    $("#"+currentColor).addClass("pressed");
    setTimeout(function(){
        $("#"+currentColor).removeClass("pressed");
    },100)
}

function startOver(){
    level = 0;
    started = false;
    gamePattern = [];
}