let roommateSearchController = null;

function updateRoommateSuggestions() {
    const guestTypeElement = document.getElementById('guest_type');
    const roomTypeElement = document.getElementById('room_type');
    const roommateInput = document.getElementById('roommates');
    const suggestionList = document.getElementById('roommate_suggestions');

    if (!guestTypeElement || !roomTypeElement || !roommateInput || !suggestionList) {
        return;
    }

    const eligible = guestTypeElement.value === 'regular_guest'
        && ['double', 'multi'].includes(roomTypeElement.value);
    const query = roommateInput.value.trim();
    suggestionList.replaceChildren();

    if (!eligible || query.length < 2) {
        if (roommateSearchController) {
            roommateSearchController.abort();
            roommateSearchController = null;
        }
        return;
    }

    if (roommateSearchController) {
        roommateSearchController.abort();
    }
    roommateSearchController = new AbortController();

    const params = new URLSearchParams({
        q: query,
        room_type: roomTypeElement.value,
    });
    fetch(`./roommate_suggestions.php?${params.toString()}`, {
        method: 'GET',
        headers: { Accept: 'application/json' },
        signal: roommateSearchController.signal,
    })
        .then((response) => response.ok ? response.json() : [])
        .then((names) => {
            if (!Array.isArray(names)) {
                return;
            }
            names.forEach((name) => {
                if (typeof name !== 'string') {
                    return;
                }
                const option = document.createElement('option');
                option.value = name;
                suggestionList.appendChild(option);
            });
        })
        .catch((error) => {
            if (error.name !== 'AbortError') {
                console.warn('Zimmernachbar-Vorschläge konnten nicht geladen werden.');
            }
        });
}

function updateRoomOptions() {
    const guestTypeElement = document.getElementById('guest_type');
    const roomTypeElement = document.getElementById('room_type');
    const regularOptions = document.getElementById('regular_guest_options');
    const dayOptions = document.getElementById('day_guest_options');
    const roommateInfo = document.getElementById('roommate_info');
    const roommateInput = document.getElementById('roommates');

    const guestType = guestTypeElement ? guestTypeElement.value : '';
    const roomType = roomTypeElement ? roomTypeElement.value : '';
    const roommateEligible = guestType === 'regular_guest' && ['double', 'multi'].includes(roomType);

    if (regularOptions) {
        regularOptions.style.display = guestType === 'regular_guest' ? 'block' : 'none';
    }
    if (dayOptions) {
        dayOptions.style.display = guestType === 'day_guest' ? 'block' : 'none';
    }
    if (roommateInfo) {
        roommateInfo.style.display = roommateEligible ? 'block' : 'none';
    }
    if (roommateInput) {
        roommateInput.disabled = !roommateEligible;
    }
    updateRoommateSuggestions();
}

document.addEventListener('DOMContentLoaded', function () {
    const guestTypeElement = document.getElementById('guest_type');
    const roomTypeElement = document.getElementById('room_type');
    const roommateInput = document.getElementById('roommates');

    if (guestTypeElement) {
        guestTypeElement.addEventListener('change', updateRoomOptions);
    }
    if (roomTypeElement) {
        roomTypeElement.addEventListener('change', updateRoomOptions);
    }
    if (roommateInput) {
        roommateInput.addEventListener('input', updateRoommateSuggestions);
    }
    updateRoomOptions();
});