let html5QrCode = null;
let currentToken = null;

const qrReader = document.getElementById("qr-reader");
const startScanBtn = document.getElementById("start-scan");
const stopScanBtn = document.getElementById("stop-scan");
const searchInput = document.getElementById("search-input");
const searchResults = document.getElementById("search-results");
const guestCard = document.getElementById("guest-card");
const guestPhoto = document.getElementById("guest-photo");
const guestName = document.getElementById("guest-name");
const guestDepartment = document.getElementById("guest-department");
const guestPosition = document.getElementById("guest-position");
const guestEmail = document.getElementById("guest-email");
const checkInStatus = document.getElementById("check-in-status");
const checkInBtn = document.getElementById("check-in-btn");
const resetBtn = document.getElementById("reset-btn");

function resetGuestCard() {
    guestCard.classList.add("d-none");
    currentToken = null;
    guestPhoto.src = "";
    guestName.textContent = "";
    guestDepartment.textContent = "";
    guestPosition.textContent = "";
    guestEmail.textContent = "";
    checkInStatus.classList.add("d-none");
    checkInStatus.className = "alert d-none";
    checkInBtn.disabled = false;
    checkInBtn.textContent = "Отметить вход";
}

function showGuest(guest) {
    currentToken = guest.token;
    guestCard.classList.remove("d-none");

    if (guest.photo_url) {
        guestPhoto.src = guest.photo_url;
        guestPhoto.classList.remove("d-none");
    } else {
        guestPhoto.src = "";
        guestPhoto.classList.add("d-none");
        // Show placeholder
        if (!guestPhoto.nextElementSibling || !guestPhoto.nextElementSibling.classList.contains("guest-photo-placeholder")) {
            const placeholder = document.createElement("div");
            placeholder.className = "guest-photo-placeholder mx-auto mb-3";
            placeholder.textContent = "Нет фото";
            guestPhoto.parentNode.insertBefore(placeholder, guestPhoto.nextSibling);
        }
    }

    guestName.textContent = guest.full_name;
    guestDepartment.textContent = guest.department;
    guestPosition.textContent = guest.position || "";
    guestEmail.textContent = guest.email;

    if (guest.checked_in) {
        checkInStatus.classList.remove("d-none", "alert-success", "alert-warning");
        checkInStatus.classList.add("alert-warning");
        checkInStatus.textContent = "Гость уже отмечен как вошедший";
        checkInBtn.disabled = true;
    } else {
        checkInStatus.classList.add("d-none");
        checkInBtn.disabled = false;
    }

    window.scrollTo({ top: guestCard.offsetTop - 20, behavior: "smooth" });
}

function loadGuestByToken(token) {
    fetch(`/api/guest/${token}`)
        .then(response => {
            if (!response.ok) throw new Error("Гость не найден");
            return response.json();
        })
        .then(guest => showGuest(guest))
        .catch(error => {
            alert(error.message);
        });
}

// QR Scanner
startScanBtn.addEventListener("click", () => {
    html5QrCode = new Html5Qrcode("qr-reader");
    Html5Qrcode.getCameras()
        .then(cameras => {
            if (cameras && cameras.length) {
                const cameraId = cameras[0].id;
                html5QrCode.start(
                    cameraId,
                    { fps: 10, qrbox: { width: 250, height: 250 } },
                    (decodedText) => {
                        html5QrCode.stop();
                        stopScanBtn.classList.add("d-none");
                        startScanBtn.classList.remove("d-none");

                        // Extract token from URL
                        const url = new URL(decodedText);
                        const token = url.searchParams.get("token");
                        if (token) {
                            loadGuestByToken(token);
                        }
                    },
                    (errorMessage) => {}
                );
                startScanBtn.classList.add("d-none");
                stopScanBtn.classList.remove("d-none");
            } else {
                alert("Камеры не найдены");
            }
        })
        .catch(err => {
            alert("Ошибка доступа к камере: " + err.message);
        });
});

stopScanBtn.addEventListener("click", () => {
    if (html5QrCode) {
        html5QrCode.stop();
    }
    stopScanBtn.classList.add("d-none");
    startScanBtn.classList.remove("d-none");
});

// Search by name
let searchTimeout = null;
searchInput.addEventListener("input", (e) => {
    const query = e.target.value.trim();
    searchResults.innerHTML = "";

    if (query.length < 2) return;

    clearTimeout(searchTimeout);
    searchTimeout = setTimeout(() => {
        fetch(`/api/guests/search?q=${encodeURIComponent(query)}`)
            .then(response => response.json())
            .then(guests => {
                searchResults.innerHTML = "";
                guests.forEach(guest => {
                    const item = document.createElement("button");
                    item.className = "list-group-item list-group-item-action";
                    item.innerHTML = `<strong>${guest.full_name}</strong><br><small>${guest.department}</small>`;
                    item.addEventListener("click", () => {
                        searchResults.innerHTML = "";
                        searchInput.value = "";
                        showGuest(guest);
                    });
                    searchResults.appendChild(item);
                });
            });
    }, 300);
});

// Check-in button
checkInBtn.addEventListener("click", () => {
    if (!currentToken) return;

    checkInBtn.disabled = true;
    checkInBtn.textContent = "Отметка...";

    fetch(`/api/check-in/${currentToken}`, { method: "POST" })
        .then(response => response.json().then(data => ({ status: response.status, data })))
        .then(({ status, data }) => {
            checkInStatus.classList.remove("d-none", "alert-success", "alert-warning", "alert-danger");
            if (data.success) {
                checkInStatus.classList.add("alert-success");
                checkInStatus.textContent = "Вход успешно отмечен!";
                checkInBtn.textContent = "Вход отмечен";
            } else if (status === 409) {
                checkInStatus.classList.add("alert-warning");
                checkInStatus.textContent = "Гость уже отмечен как вошедший";
                checkInBtn.textContent = "Уже отмечен";
            } else {
                checkInStatus.classList.add("alert-danger");
                checkInStatus.textContent = data.message || "Ошибка";
                checkInBtn.disabled = false;
                checkInBtn.textContent = "Отметить вход";
            }
        })
        .catch(error => {
            checkInStatus.classList.remove("d-none", "alert-success", "alert-warning", "alert-danger");
            checkInStatus.classList.add("alert-danger");
            checkInStatus.textContent = "Ошибка сети: " + error.message;
            checkInBtn.disabled = false;
            checkInBtn.textContent = "Отметить вход";
        });
});

resetBtn.addEventListener("click", resetGuestCard);

// If token is in URL (scanned via external scanner)
document.addEventListener("DOMContentLoaded", () => {
    const urlParams = new URLSearchParams(window.location.search);
    const token = urlParams.get("token");
    if (token) {
        loadGuestByToken(token);
    }
});