script.js

const buttonColors = ["red","green","blue","yellow"];

let level = 0;
let isStarted = false;
let sequencePattern = [];
let userSequencePattern = [];


document.addEventListener("keypress",() => {
   if(!isStarted){
    document.body.style.backgroundColor = "#024";
    document.getElementById("title").textContent = "Level " + level
    nextSequence();
    isStarted = true;
   }
})

document.querySelectorAll(".btn").forEach((btn) => {
    btn.addEventListener("click",function(){
        const userChosenColor = this.id;
        userSequencePattern.push(userChosenColor);
        playSound(userChosenColor);
        userPress(userChosenColor);
        buttonPressCheck(userSequencePattern.length - 1);
    })
})

function buttonPressCheck(currentLevel){
   
    if(sequencePattern[currentLevel] === userSequencePattern[currentLevel]){
        if(sequencePattern.length === userSequencePattern.length){
            setTimeout(() => {
                nextSequence();
            },1000);
        }
    } 
    else {
        gameOver()
    }
}
function nextSequence(){
    userSequencePattern = []
    level++;
    document.getElementById("title").textContent = "level" + level;
    const randomNumber = Math.floor(Math.random()*4);
    const randomColor = buttonColors[randomNumber];
    sequencePattern.push(randomColor)
    const button = document.getElementById(randomColor);
    button.style.opacity = "0";
    setTimeout(() => {
        button.style.opacity = "1";

    },100)
    playSound(randomColor);
} 



function userPress(colorName){
    const button = document.getElementById(colorName)
    button.classList.add("pressedButton");
    setTimeout(() => {
        button.classList.remove("pressedButton");
    }, 100);

}

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

function gameOver(){
    document.getElementById("title").textContent = "Game Over!, Press to Start";
    document.body.style.backgroundColor = "red";

    restart();
}

function restart(){
    isStarted = false;
    level = 0;
    sequencePattern = [];
    userSequencePattern = [];
}