console.log("App.js caricato - VU Meter & Click-to-Tune attivi!");

let ws = null;
let audioCtx = null;
let gainNode = null;
let analyser = null;
let dataArray = null;
let nextStartTime = 0;

const connectBtn = document.getElementById('connectBtn');
const tgInput = document.getElementById('tgInput');
const setTgBtn = document.getElementById('setTgBtn');
const displayScreen = document.getElementById('displayScreen');
const statusText = document.getElementById('statusText');
const volumeSlider = document.getElementById('volumeSlider');
const volumeValue = document.getElementById('volumeValue');
const liveTrafficList = document.getElementById('liveTrafficList');
const vuMeterBar = document.getElementById('vuMeterBar');

if(statusText) statusText.innerText = "✅ Sistema pronto. Clicca Avvia Ascolto.";

if(volumeSlider) {
    volumeSlider.addEventListener('input', (e) => {
        const val = parseFloat(e.target.value);
        if(volumeValue) volumeValue.innerText = Math.round(val * 100) + '%';
        if (gainNode) gainNode.gain.value = val;
    });
}

window.setQuickTg = function(valore) {
    if (tgInput) tgInput.value = valore;
    inviaCambioTG(valore);
};

function inviaCambioTG(nuovoTG) {
    if (!nuovoTG || nuovoTG <= 0) return;
    if (ws && ws.readyState === WebSocket.OPEN) {
        ws.send(JSON.stringify({ action: "cambia_tg", tg: nuovoTG }));
        if(displayScreen) displayScreen.innerText = "SINTONIA...";
        if(statusText) statusText.innerText = "Sintonizzato su TG " + nuovoTG;
    } else {
        if(statusText) statusText.innerText = "Pronto a sintonizzare TG " + nuovoTG + " (Avvia prima)";
    }
}

// --- VU METER LOOP ---
function renderVUMeter() {
    requestAnimationFrame(renderVUMeter);
    if (!analyser || !vuMeterBar) return;

    analyser.getByteTimeDomainData(dataArray);
    let sum = 0;
    for(let i = 0; i < dataArray.length; i++) {
        let v = (dataArray[i] - 128) / 128.0;
        sum += v * v;
    }
    let rms = Math.sqrt(sum / dataArray.length);
    let percent = Math.min(100, rms * 500); // Moltiplicatore di sensibilità grafica

    vuMeterBar.style.width = percent + '%';
    if (percent > 85) vuMeterBar.style.background = '#e74c3c'; // Rosso saturo
    else if (percent > 50) vuMeterBar.style.background = '#f1c40f'; // Giallo
    else vuMeterBar.style.background = '#2ecc71'; // Verde standard
}

function playPCM320(arrayBuffer) {
    if (!audioCtx || !analyser) return;
    try {
        const int16Array = new Int16Array(arrayBuffer);
        const float32Array = new Float32Array(int16Array.length);
        for (let i = 0; i < int16Array.length; i++) {
            float32Array[i] = int16Array[i] / 32768.0;
        }

        const buffer = audioCtx.createBuffer(1, float32Array.length, 8000);
        buffer.getChannelData(0).set(float32Array);

        const source = audioCtx.createBufferSource();
        source.buffer = buffer;
        
        // Collega al VU meter, che a sua volta è collegato al volume
        source.connect(analyser);

        const currentTime = audioCtx.currentTime;
        if (nextStartTime < currentTime) nextStartTime = currentTime + 0.02; 
        source.start(nextStartTime);
        nextStartTime += buffer.duration;
    } catch(err) {
        console.error("Errore audio:", err);
    }
}

function startAudio() {
    try {
        if (!audioCtx) {
            audioCtx = new (window.AudioContext || window.webkitAudioContext)();
            
            analyser = audioCtx.createAnalyser();
            analyser.fftSize = 256;
            dataArray = new Uint8Array(analyser.frequencyBinCount);
            
            gainNode = audioCtx.createGain();
            
            // Catena: Source -> Analyser(VU) -> Gain(Volume) -> Casse
            analyser.connect(gainNode);
            gainNode.connect(audioCtx.destination);
            
            if(volumeSlider) gainNode.gain.value = parseFloat(volumeSlider.value);
            
            renderVUMeter(); // Avvia l'animazione grafica
        }
        if (audioCtx.state === 'suspended') audioCtx.resume();
        if(statusText) statusText.innerText = "🔄 Connessione in corso...";

        const protocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
        ws = new WebSocket(`${protocol}//${window.location.host}/ws`);
        ws.binaryType = 'arraybuffer';

        ws.onopen = () => {
            if(connectBtn) connectBtn.style.display = 'none';
            if(tgInput) inviaCambioTG(tgInput.value);
        };

        ws.onmessage = (event) => {
            if (event.data instanceof ArrayBuffer) {
                playPCM320(event.data);
            } else if (typeof event.data === 'string') {
                const data = JSON.parse(event.data);
                
                if (data.action === "error") return;

                if (data.action === "display") {
                    if(displayScreen) {
                        displayScreen.innerText = data.text;
                        displayScreen.style.background = data.active ? "#e67e22" : "#1abc9c";
                    }
                    if(statusText) statusText.style.color = "#bdc3c7"; 
                }
                
                // CLICK-TO-TUNE IMPLEMENTATO QUI
                if (data.action === "global_traffic" && liveTrafficList) {
                    if (!data.data || data.data.length === 0) {
                        liveTrafficList.innerHTML = "Nessun traffico in corso...";
                    } else {
                        liveTrafficList.innerHTML = data.data.map(item => 
                            `<div class="traffic-item traffic-clickable" onclick="setQuickTg(${item.tg})" title="Clicca per sintonizzare TG ${item.tg}">
                                <b>TG ${item.tg}</b>: ${item.src}
                            </div>`
                        ).join("");
                    }
                }
            }
        };

        ws.onclose = () => {
            if(statusText) statusText.innerText = "❌ Connessione persa.";
            if(connectBtn) connectBtn.style.display = 'block';
        };

    } catch (err) {
        console.error("Errore in avvio:", err);
    }
}

if(connectBtn) connectBtn.addEventListener('click', startAudio);
if(setTgBtn) setTgBtn.addEventListener('click', () => { if(tgInput) inviaCambioTG(tgInput.value); });
if(tgInput) {
    tgInput.addEventListener('keypress', (e) => {
        if (e.key === 'Enter') inviaCambioTG(tgInput.value);
    });
}