// hello, dear ctfer
// here is some govnokod
// but it is not necessary to see it
// vuln is in server side

const cards = document.querySelectorAll('.memory-card');

let hasFlippedCard = false;
let lockBoard = false;
let firstCard, secondCard;
let right = 0;

function getInfo(img) {
    var xhr = new XMLHttpRequest();
    xhr.open('GET', '?getInfo=' + img.id, false);
    xhr.send();


    if (xhr.status === 200) {
        var response = JSON.parse(xhr.response);
        if (response.error == "WASTED"){
            alert("Sorry, it is the end..) more than 3 errors.");
            location.reload();

        } else {
            if (response.flag != 0) alert(response.flag);
            console.log(response);
            img.src = response.card + '.jpg';
            document.getElementById("error").innerText = response.errors;
            document.getElementById("passes").innerText = response.passes;
        }
    }
    else {
        alert('Request failed.  Returned status of ' + xhr.status);
    }


}

function sendAnswer() {
    var answer = '';
    cards.forEach(card => answer += card.children[0].src.split('.')[1].slice(-1) + ',');

    answer = answer.slice(0, -1);

    var xhr = new XMLHttpRequest();
    xhr.open('GET', '?answers=' + answer, false);
    xhr.send();

    if (xhr.status === 200) {
        var response = JSON.parse(xhr.response);
        if (response.error == "WASTED"){
            alert("WASTED, SOrry))");
            document.getElementById("error").innerText = response.errors;
            document.getElementById("passes").innerText = response.passes;
            initBoard();

        } else {
            if (response.flag != 0) alert(response.flag);
            console.log(response);
            document.getElementById("error").innerText = response.errors;
            document.getElementById("passes").innerText = response.passes;

            initBoard();
        }
    }
    else {
        alert('Request failed.  Returned status of ' + xhr.status);
    }
}

function flipCard() {
    if (lockBoard) return;
    if (this === firstCard) return;

    var img = this.children[0];

    getInfo(img);

    this.classList.add('flip');

    if (!hasFlippedCard) {
        hasFlippedCard = true;
        firstCard = this;

        return;
    }

    secondCard = this;
    checkForMatch();
}

function checkForMatch() {
    let isMatch = firstCard.children[0].src == secondCard.children[0].src;

    isMatch ? disableCards() : disableCards();
}

function disableCards() {
    firstCard.removeEventListener('click', flipCard);
    secondCard.removeEventListener('click', flipCard);

    resetBoard();

    right += 2;
    if (right == 12){
        sendAnswer();
    }
}

function unflipCards() {
    lockBoard = true;

    setTimeout(() => {
        firstCard.classList.remove('flip');
        secondCard.classList.remove('flip');

        resetBoard();
    }, 1500);
}

function resetBoard() {
    [hasFlippedCard, lockBoard] = [false, false];
    [firstCard, secondCard] = [null, null];
}

function initBoard(){
    resetBoard();
    cards.forEach(card => card.classList.remove('flip'));
    cards.forEach(card => card.addEventListener('click', flipCard));
    right = 0;
}

cards.forEach(card => card.addEventListener('click', flipCard));