document.addEventListener('DOMContentLoaded', function () {
    // === Abschnitt: Globale Variablen ===
    const presetContainer = document.getElementById('preset-container');
    const newPresetForm = document.getElementById('new-preset-form');
    const newPresetNameInput = document.getElementById('new-preset-name');
    const newPresetUrlInput = document.getElementById('new-preset-url');
    const exportButton = document.getElementById('export-button');
    const importButton = document.getElementById('import-button');
    const loadPresetsLink = document.getElementById('load-presets-link');
    const stopButton = document.querySelector('.stop-button');
    const currentStationName = document.getElementById('current-station-name');
    let currentPlayingItem = null; // Speichert das aktuell spielende Element

    // === Abschnitt: Initialisierung ===
    initializeFooter();
    initializeEventListeners();
    loadExistingPresets();
    setupSortable();

    // === Funktion: Footer dynamisch aktualisieren ===
    function initializeFooter() {
        const currentYear = new Date().getFullYear();
        const currentYearElement = document.getElementById('current-year');
        if (currentYearElement) {
            currentYearElement.textContent = currentYear;
        }

        const serverName = window.location.hostname;
        const serverNameElement = document.getElementById('server-name');
        if (serverNameElement) {
            serverNameElement.textContent = serverName;
        }
    }

    // === Funktion: Titel dynamisch ändern ===
    function updateTitle(stationName) {
        if (stationName) {
            document.title = `${stationName} - Radioplayer mit Presets`;
        } else {
            document.title = "Radioplayer mit Presets";
        }
    }

    // === Abschnitt: Event-Listener ===
    function initializeEventListeners() {
        newPresetForm.addEventListener('submit', (event) => {
            event.preventDefault(); // Verhindert die Standardaktion (Seiten-Reload)

            const presetName = newPresetNameInput.value.trim();
            const presetUrl = newPresetUrlInput.value.trim();

            if (!presetName || !presetUrl) {
                alert("Bitte geben Sie einen Namen und eine URL ein.");
                return;
            }

            // URL-Validierung: Prüfen, ob die URL mit http:// oder https:// beginnt
            if (!isValidHttpUrl(presetUrl)) {
                alert("Bitte geben Sie eine gültige HTTP- oder HTTPS-URL ein.");
                return;
            }

            addNewPreset(presetName, presetUrl);
            savePresetToLocalStorage(presetName, presetUrl);

            // Felder zurücksetzen
            newPresetNameInput.value = '';
            newPresetUrlInput.value = '';
        });

    // Hilfsfunktion zur Überprüfung von URLs
        function isValidHttpUrl(url) {
            try {
                const parsedUrl = new URL(url);
                return parsedUrl.protocol === "http:" || parsedUrl.protocol === "https:";
            } catch (e) {
                return false;
            }
        }

        exportButton.addEventListener('click', exportPresets);
        importButton.addEventListener('click', importPresets);
        loadPresetsLink.addEventListener('click', loadPresetsFromFile);
        stopButton.addEventListener('click', stopPlayback);
    }

    // === Funktion: Preset-Handling ===
    function loadExistingPresets() {
        const presets = JSON.parse(localStorage.getItem('presets')) || [];
        presets.forEach(preset => addNewPreset(preset.name, preset.url));
    }

    function addNewPreset(name, url) {
        const presetItem = document.createElement('div');
        presetItem.classList.add('preset-item');
        presetItem.dataset.streamUrl = url;

        presetItem.innerHTML = `
            <h3>${name}</h3>
            <div class="button-container">
                <button class="move-button"><i class="fas fa-arrows-alt"></i></button>
                <button class="edit-button"><i class="fas fa-edit"></i></button>
                <button class="delete-button"><i class="fas fa-trash-alt"></i></button>
            </div>
        `;

        presetItem.querySelector('.edit-button').addEventListener('click', (event) => {
            event.stopPropagation();
            editPreset(presetItem, name, url);
        });

        presetItem.querySelector('.delete-button').addEventListener('click', (event) => {
            event.stopPropagation();
            deletePreset(presetItem);
        });

        presetItem.addEventListener('click', () => playStream(url, presetItem));

        presetContainer.appendChild(presetItem);
    }

    function editPreset(item, currentName, currentUrl) {
        const newName = prompt("Neuer Name:", currentName);
        const newUrl = prompt("Neue URL:", currentUrl);

        if (newName !== null && newUrl !== null) {
            item.querySelector('h3').textContent = newName;
            item.dataset.streamUrl = newUrl;
            savePresetOrder();
        }
    }

    function deletePreset(item) {
        if (confirm("Möchten Sie diesen Sender wirklich löschen?")) {
            presetContainer.removeChild(item);
            savePresetOrder();
        }
    }

    function savePresetToLocalStorage(name, url) {
        const presets = JSON.parse(localStorage.getItem('presets')) || [];
        presets.push({ name, url });
        localStorage.setItem('presets', JSON.stringify(presets));
    }

    function savePresetOrder() {
        const presetItems = Array.from(presetContainer.children);
        const presets = presetItems.map(item => ({
            name: item.querySelector('h3').textContent,
            url: item.dataset.streamUrl
        }));
        localStorage.setItem('presets', JSON.stringify(presets));
    }

    // === Funktion: Audio-Handling ===
    function playStream(url, item) {
        if (currentPlayingItem) {
            const currentAudio = currentPlayingItem.querySelector('audio');
            if (currentAudio) {
                currentAudio.pause();
                currentAudio.remove();
            }
            currentPlayingItem.classList.remove('playing');
        }

        const audioElement = new Audio(url);
        audioElement.autoplay = true;
        audioElement.loop = true;
        audioElement.volume = 0.5;
        audioElement.onerror = () => alert('Fehler beim Laden des Streams: ' + url);

        item.appendChild(audioElement);
        item.classList.add('playing');
        currentPlayingItem = item;
        currentStationName.textContent = item.querySelector('h3').textContent;

        updateTitle(item.querySelector('h3').textContent); // Sendername in den Titel einfügen
    }

    function stopPlayback() {
        if (currentPlayingItem) {
            const audioElement = currentPlayingItem.querySelector('audio');
            if (audioElement) {
                audioElement.pause();
                audioElement.currentTime = 0;
                currentPlayingItem.classList.remove('playing');
                currentPlayingItem = null;
                currentStationName.textContent = 'Kein Sender ausgewählt.';
            }
        }

        updateTitle('');
    }

    // === Funktion: Preset-Import und -Export ===
    function exportPresets() {
        const presets = JSON.parse(localStorage.getItem('presets')) || [];
        const json = JSON.stringify(presets, null, 2);

        const blob = new Blob([json], { type: 'application/json' });
        const url = URL.createObjectURL(blob);

        const a = document.createElement('a');
        a.href = url;
        a.download = 'webradio_presets.json';
        a.click();

        URL.revokeObjectURL(url);
    }

    function importPresets() {
        const input = document.createElement('input');
        input.type = 'file';
        input.accept = '.json';
        input.addEventListener('change', (event) => {
            const file = event.target.files[0];
            if (file) {
                const reader = new FileReader();
                reader.onload = (e) => {
                    try {
                        const importedPresets = JSON.parse(e.target.result);
                        if (Array.isArray(importedPresets)) {
                            localStorage.setItem('presets', JSON.stringify(importedPresets));
                            presetContainer.innerHTML = '';
                            importedPresets.forEach(preset => addNewPreset(preset.name, preset.url));
                            alert("Presets erfolgreich importiert.");
                        } else {
                            throw new Error("Ungültiges Format.");
                        }
                    } catch (error) {
                        alert("Fehler beim Importieren: " + error.message);
                    }
                };
                reader.readAsText(file);
            }
        });
        input.click();
    }

    function loadPresetsFromFile(event) {
        event.preventDefault();

        fetch('/webradio_presets.json')
            .then(response => {
                if (!response.ok) {
                    throw new Error('Datei konnte nicht geladen werden');
                }
                return response.json();
            })
            .then(data => {
                localStorage.setItem('presets', JSON.stringify(data));
                presetContainer.innerHTML = '';
                data.forEach(preset => addNewPreset(preset.name, preset.url));
                alert('Presets erfolgreich geladen.');
            })
            .catch(error => alert('Fehler: ' + error.message));
    }

    // === Funktion: Sortierbare Presets ===
    function setupSortable() {
        new Sortable(presetContainer, {
            animation: 250,
            ghostClass: 'ghost',
            handle: '.move-button',
            onEnd: savePresetOrder
        });
    }
});