// Voice Assistant — LiveKit client
const { Room, RoomEvent } = LivekitClient;

// ── Config ──────────────────────────────────────────────────────────────────
// LiveKit is reached through the same origin as the page (nginx proxies
// /livekit -> localhost:7880). Keeps a single HTTPS port and avoids mixed
// content when the UI is served over HTTPS.
const LIVEKIT_URL = `${window.location.protocol === "https:" ? "wss" : "ws"}://${window.location.host}/livekit`;
const ROOM_NAME = "voice-room";
const AGENT_NAME = "voice-assistant";

const VOICES = [
    { id: "en-US-Ava:DragonHDOmniLatestNeural", name: "Ava", tag: "Dragon HD Omni" },
    { id: "en-US-JennyNeural", name: "Jenny" },
    { id: "en-US-GuyNeural", name: "Guy" },
    { id: "en-US-AndrewNeural", name: "Andrew" },
    { id: "en-US-AriaNeural", name: "Aria" },
    { id: "en-US-EmmaNeural", name: "Emma" },
    { id: "en-US-EricNeural", name: "Eric" },
    { id: "en-US-BrianNeural", name: "Brian" },
    { id: "en-US-AshleyNeural", name: "Ashley" },
    { id: "en-US-RichardNeural", name: "Richard" },
    { id: "en-US-TinaNeural", name: "Tina" },
    { id: "en-US-SteffanNeural", name: "Steffan" },
];

const HISTORY_KEY = "voice_history";
const HISTORY_MAX = 50;
const MODE_KEY = "hope_conversation_mode";
const MODEL_KEY = "preferred_model";

// ── State ───────────────────────────────────────────────────────────────────
let room = null;
let agentParticipant = null;
let agentReady = false;
let uiState = "idle";            // idle | connecting | listening | thinking | speaking
let micLevel = 0;                // 0..1, smoothed
let agentAudioLevel = 0;         // 0..1, smoothed
let userSpeaking = false;        // local VAD-ish flag from mic level
let wakeLock = null;
let conversationMode = localStorage.getItem(MODE_KEY) === "text" ? "text" : "voice";
let connectionPromise = null;

// ── Model (brain) state — populated from the agent's data channel ──────────
let availableModels = [];          // ids published by the agent
let selectedModel = localStorage.getItem(MODEL_KEY) || null;

function escapeHtml(s) {
    const d = document.createElement("div");
    d.textContent = s || "";
    return d.innerHTML;
}

// ── DOM ─────────────────────────────────────────────────────────────────────
const startBtn = document.getElementById("startBtn");
const stopBtn = document.getElementById("stopBtn");
const muteBtn = document.getElementById("muteBtn");
let micMuted = false;
const statusEl = document.getElementById("status");
const messagesEl = document.getElementById("messages");
const ledWallEl = document.getElementById("ledWall");
const stateLabelEl = document.getElementById("stateLabel");
const thinkingChipEl = document.getElementById("thinkingChip");
const bargeHintEl = document.getElementById("bargeHint");
const micMeterFillEl = document.getElementById("micMeterFill");
const settingsBtn = document.getElementById("settingsBtn");
const settingsSheet = document.getElementById("settingsSheet");
const sheetBackdrop = document.getElementById("sheetBackdrop");
const closeSheetBtn = document.getElementById("closeSheetBtn");
const voiceListEl = document.getElementById("voiceList");
const modelListEl = document.getElementById("modelList");
const modelNoteEl = document.getElementById("modelNote");
const clearBtn = document.getElementById("clearBtn");
const tasksBtn = document.getElementById("tasksBtn");
const tasksPanel = document.getElementById("tasksPanel");
const tasksList = document.getElementById("tasksList");
const tasksBadge = document.getElementById("tasksBadge");
const closeTasksBtn = document.getElementById("closeTasksBtn");
const voiceModeBtn = document.getElementById("voiceModeBtn");
const textModeBtn = document.getElementById("textModeBtn");
const modeDescriptionEl = document.getElementById("modeDescription");
const transcriptModeLabelEl = document.getElementById("transcriptModeLabel");
const chatComposer = document.getElementById("chatComposer");
const chatInput = document.getElementById("chatInput");
const sendChatBtn = document.getElementById("sendChatBtn");

// ── Background tasks state ──────────────────────────────────────────────────
const tasks = new Map(); // task_id -> {id, description, status, steps: [], result, error}

function updateTasksBadge() {
    const active = [...tasks.values()].filter(t => t.status === "running" || t.status === "pending").length;
    if (active > 0) {
        tasksBadge.hidden = false;
        tasksBadge.textContent = String(active);
    } else {
        tasksBadge.hidden = true;
    }
}

function renderTasks() {
    const items = [...tasks.values()].sort((a, b) => (b.created_at || 0) - (a.created_at || 0));
    if (items.length === 0) {
        tasksList.innerHTML = '<div class="tasks-empty"><strong>Nothing running</strong><span>Ask Hope to research or compare something.</span></div>';
        return;
    }
    tasksList.innerHTML = "";
    for (const t of items) {
        const card = document.createElement("div");
        card.className = "task-card";
        const statusClass = t.status || "pending";
        card.innerHTML = `
            <div class="task-card-header">
                <span class="task-status-dot ${statusClass}"></span>
                <span class="task-desc">${escapeHtml(t.description)}</span>
            </div>
            <ul class="task-steps">${t.steps.map(s => `<li class="task-step ${s.role}">${escapeHtml(s.content)}</li>`).join("")}</ul>
            ${t.result ? `<div class="task-result">${escapeHtml(t.result)}</div>` : ""}
            ${t.error ? `<div class="task-error">${escapeHtml(t.error)}</div>` : ""}
        `;
        tasksList.appendChild(card);
    }
}

function handleTaskEvent(data) {
    const { task_id, event, role, content, result, error, task } = data;
    if (event === "created" && task) {
        tasks.set(task_id, { ...task, steps: [] });
    } else if (event === "step") {
        const t = tasks.get(task_id);
        if (t) {
            t.steps.push({ role, content });
            t.status = "running";
        }
    } else if (event === "completed") {
        const t = tasks.get(task_id);
        if (t) { t.status = "completed"; t.result = result; }
    } else if (event === "failed") {
        const t = tasks.get(task_id);
        if (t) { t.status = "failed"; t.error = error; }
    }
    updateTasksBadge();
    renderTasks();
}

function setTasksOpen(open) {
    tasksPanel.classList.toggle("open", open);
    tasksBtn.setAttribute("aria-expanded", String(open));
}

tasksBtn.setAttribute("aria-expanded", "false");
tasksBtn.addEventListener("click", () => setTasksOpen(!tasksPanel.classList.contains("open")));
closeTasksBtn.addEventListener("click", () => setTasksOpen(false));

// ── Voice / text mode ──────────────────────────────────────────────────────
function updateModeUI() {
    const isText = conversationMode === "text";
    document.body.dataset.mode = conversationMode;
    voiceModeBtn.classList.toggle("active", !isText);
    textModeBtn.classList.toggle("active", isText);
    voiceModeBtn.setAttribute("aria-pressed", String(!isText));
    textModeBtn.setAttribute("aria-pressed", String(isText));
    modeDescriptionEl.textContent = isText
        ? "Type when quiet is better. Switch back to voice without losing the thread."
        : "Speak naturally. I’ll listen, remember, and answer in real time.";
    transcriptModeLabelEl.textContent = isText ? "Shared voice and text history" : "Live voice transcript";
    startBtn.innerHTML = isText
        ? '<span class="button-spark" aria-hidden="true"></span>Connect to Hope'
        : '<span class="button-spark" aria-hidden="true"></span>Start conversation';
    if (isText) {
        setState(room ? "listening" : "idle");
        window.setTimeout(() => chatInput.focus(), 0);
    } else {
        // Refresh mode-specific copy even when the underlying state is unchanged.
        setState(uiState);
    }
}

async function setConversationMode(mode) {
    if (mode !== "voice" && mode !== "text") return;
    const previousMode = conversationMode;
    conversationMode = mode;
    localStorage.setItem(MODE_KEY, mode);
    updateModeUI();
    if (mode === "voice" && previousMode === "text") {
        chatInput.blur();
        window.setTimeout(() => {
            document.querySelector(".workspace").scrollIntoView({ block: "start", behavior: "smooth" });
        }, 0);
    }

    if (!room || !room.localParticipant) return;
    sendModeMessage(mode);
    if (mode === "text") {
        await room.localParticipant.setMicrophoneEnabled(false);
        micMuted = true;
        muteBtn.disabled = true;
        updateMuteIcon();
        stopVisualLoop();
        statusEl.textContent = "Secure room · Text mode";
    } else {
        micMuted = false;
        muteBtn.disabled = false;
        updateMuteIcon();
        startVisualLoop();
        try {
            await room.startAudio();
            await room.localParticipant.setMicrophoneEnabled(true);
            setupMicAnalyser();
            statusEl.textContent = "Secure room · Microphone on";
        } catch (err) {
            // Keep the conversation usable even if this browser denies or does
            // not implement microphone capture. The mute control can retry.
            console.warn("Microphone could not be enabled:", err);
            micMuted = true;
            updateMuteIcon();
            statusEl.textContent = "Voice mode · Microphone unavailable";
        }
    }
}

voiceModeBtn.addEventListener("click", () => setConversationMode("voice").catch(console.error));
textModeBtn.addEventListener("click", () => setConversationMode("text").catch(console.error));

// ── Audio analysers (mic + remote agent audio) ─────────────────────────────
let micCtx = null;
let micAnalyser = null;
let micBuf = null;
let remoteCtx = null;
let remoteAnalyser = null;
let remoteFreqBuf = null;

function setupMicAnalyser() {
    try {
        const pub = room.localParticipant.getTrackPublication(LivekitClient.Track.Source.Microphone);
        const mst = pub && pub.track && pub.track.mediaStreamTrack;
        if (mst) {
            micCtx = new AudioContext();
            micAnalyser = micCtx.createAnalyser();
            micAnalyser.fftSize = 512;
            micBuf = new Float32Array(micAnalyser.fftSize);
            micCtx.createMediaStreamSource(new MediaStream([mst])).connect(micAnalyser);
        }
    } catch (e) { /* fall back to SDK audioLevel in the meter loop */ }
}

function setupRemoteAudioAnalyser(audioEl) {
    try {
        if (!audioEl.srcObject) return;
        remoteCtx = new AudioContext();
        remoteAnalyser = remoteCtx.createAnalyser();
        remoteAnalyser.fftSize = 256;
        remoteFreqBuf = new Uint8Array(remoteAnalyser.frequencyBinCount);
        remoteCtx.createMediaStreamSource(audioEl.srcObject).connect(remoteAnalyser);
    } catch (e) { /* analyser optional */ }
}

function teardownAudio() {
    for (const ctx of [micCtx, remoteCtx]) {
        if (ctx && ctx.state !== "closed") ctx.close().catch(() => {});
    }
    micCtx = micAnalyser = micBuf = null;
    remoteCtx = remoteAnalyser = remoteFreqBuf = null;
}

// ── LED wall — a grid of dots that pulses with the agent's audio ────────────
const LED_COLS = 21;
const LED_ROWS = 21;
const LED_GROW = 1.4;               // how much the dots grow toward the center
let ledDots = [];
let ledWallTime = 0;


function buildLedWall() {
    const inner = Math.floor(LED_COLS / 2);
    const frag = document.createDocumentFragment();
    for (let r = 0; r < LED_ROWS; r++) {
        for (let c = 0; c < LED_COLS; c++) {
            const b = document.createElement("button");
            b.type = "button";
            b.className = "led-dot";
            b.disabled = true;
            b.tabIndex = -1;
            // Radial position: 0 at the center, 1 at the corner
            const dx = (c - inner) / (LED_COLS / 2);
            const dy = (r - inner) / (LED_ROWS / 2);
            const rad = Math.sqrt(dx * dx + dy * dy);
            // Push a radial cluster toward the center; scale its base brightness down
            // as it moves outward so the wall reads as a soft round bloom.
            b.dataset.rad = rad.toFixed(4);
            // A per-dot phase so the wave ripples rather than flashing in unison.
            b.dataset.phase = (Math.sin(r * 12.9898 + c * 78.233) * 43758.5453 % 1 * Math.PI * 2).toFixed(3);
            ledDots.push(b);
            frag.appendChild(b);
        }
    }
    ledWallEl.appendChild(frag);
}

// Renders one frame of the LED wall. `level` is 0..1 (agent audio when speaking,
// mic when listening). `mode` picks the palette/gradient by conversation state.
function renderLedWall(level, mode) {
    ledWallTime += 1;
    ledWallEl.dataset.mode = mode;
    const n = ledDots.length;
    for (let i = 0; i < n; i++) {
        const dot = ledDots[i];
        const rad = parseFloat(dot.dataset.rad);
        const phase = parseFloat(dot.dataset.phase || 0);

        let vis = 0;
        let size = 1;

        if (mode === "idle") {
            // A faint, static dot matrix — present but clearly dormant.
            vis = 0.16 - rad * 0.08;
            size = 1;
        } else if (level > 0.005) {
            // Centered breathing bloom that widens and brightens with the
            // signal. A soft gaussian falloff keeps it circular; a gentle
            // per-dot phase ripple adds life without banding.
            const lvl = Math.min(1, level * 1.3);
            const falloff = Math.exp(-rad * rad * (2.0 - lvl * 1.1));
            const ripple = 0.62 + 0.38 * Math.sin(ledWallTime * 0.32 + phase);
            vis = falloff * (0.35 + lvl) * ripple;
            size = 1 + (1 - rad) * LED_GROW * lvl;
            // Keep listening dimmer than speaking so the wall leans into the
            // agent's output.
            if (mode !== "speaking") vis *= 0.55;
        } else {
            // Powered state with no signal (e.g. thinking gap) — soft breathing.
            const breathe = 0.5 + 0.5 * Math.sin(ledWallTime * 0.12 + phase);
            vis = 0.14 - rad * 0.06 + 0.04 * breathe;
            size = 1 + (1 - rad) * 0.3;
        }

        vis = Math.max(0.02, Math.min(1, vis));
        // Dot grows toward the center and sits on a subtle 4px grid inset.
        const px = (2 * size).toFixed(1);
        dot.style.setProperty("--sz", `${px}px`);
        dot.style.opacity = vis.toFixed(3);
    }
}

function readMicLevel() {
    let level = 0;
    if (micAnalyser && micBuf) {
        micAnalyser.getFloatTimeDomainData(micBuf);
        for (let i = 0; i < micBuf.length; i++) level = Math.max(level, Math.abs(micBuf[i]));
    } else if (room && room.localParticipant) {
        level = room.localParticipant.audioLevel || 0;
    }
    // Smooth so the orb pulses rather than flickers
    micLevel = micLevel * 0.6 + level * 0.4;
    return micLevel;
}

function readAgentAudioLevel() {
    let level = 0;
    if (remoteAnalyser && remoteFreqBuf) {
        remoteAnalyser.getByteFrequencyData(remoteFreqBuf);
        for (let i = 0; i < remoteFreqBuf.length; i++) level = Math.max(level, remoteFreqBuf[i]);
        level /= 255;
    } else if (agentParticipant && agentParticipant.audioLevel !== undefined) {
        level = agentParticipant.audioLevel || 0;
    }
    agentAudioLevel = agentAudioLevel * 0.6 + level * 0.4;
    return agentAudioLevel;
}

// ── State machine ───────────────────────────────────────────────────────────
const STATE_LABELS = {
    voice: {
        idle: "Ready when you are",
        connecting: "Opening a secure room",
        listening: "Listening",
        thinking: "Thinking it through",
        speaking: "Hope is speaking",
    },
    text: {
        idle: "Ready to type",
        connecting: "Opening a secure room",
        listening: "Text chat ready",
        thinking: "Hope is writing",
        speaking: "Hope replied",
    },
};

function setState(next) {
    uiState = next;
    ledWallEl.dataset.state = next;
    stateLabelEl.textContent = STATE_LABELS[conversationMode][next] || next;

    // Thinking timer: show the "thinking..." chip if it lingers past 2s
    if (next === "thinking") {
        thinkingChipEl.hidden = true;
        setTimeout(() => {
            if (uiState === "thinking") thinkingChipEl.hidden = false;
        }, 2000);
    } else {
        thinkingChipEl.hidden = true;
    }

    // Barge-in hint only while the agent is speaking
    bargeHintEl.hidden = next !== "speaking";

    if (next === "idle") {
        micLevel = 0;
        agentAudioLevel = 0;
        userSpeaking = false;
    }
}

updateModeUI();

function inferState() {
    if (!room || !room.localParticipant) return "idle";
    if (!agentParticipant) return "connecting";
    readMicLevel();
    readAgentAudioLevel();
    userSpeaking = micLevel > 0.035;
    if (agentAudioLevel > 0.02) return "speaking";
    if (userSpeaking) return "listening";
    // Once agent audio ends, return to listening. The previous implementation
    // converted speaking → thinking forever, leaving the UI apparently frozen.
    if (uiState === "speaking") return "listening";
    if (uiState === "thinking") return "thinking";
    return "listening";
}

// ── Visual loop: drives orb + meter + state inference ───────────────────────
let visualTimer = null;
function startVisualLoop() {
    if (visualTimer) clearInterval(visualTimer);
    visualTimer = setInterval(() => {
        if (!room || !room.localParticipant) return;
        setState(inferState());

        // Mic meter (thin bar under the status line)
        micMeterFillEl.style.width = `${Math.min(100, Math.round(micLevel * 250))}%`;

        // LED wall: pulse on the agent's rendered audio when speaking, the mic
        // while listening, and hold a faint matrix when idle.
        if (uiState === "speaking") {
            renderLedWall(agentAudioLevel, "speaking");
        } else if (uiState === "listening" && userSpeaking) {
            renderLedWall(micLevel, "listening");
        } else {
            renderLedWall(0, "idle");
        }

        // Agent audio visualizer bars on the latest agent bubble
        const viz = messagesEl.querySelector(".message-row.agent:last-of-type .audio-viz");
        if (viz) {
            let level = 0;
            if (remoteAnalyser && remoteFreqBuf) {
                for (let i = 0; i < remoteFreqBuf.length; i++) level = Math.max(level, remoteFreqBuf[i]);
                level /= 255;
            }
            const bars = viz.children;
            for (let i = 0; i < bars.length; i++) {
                // Per-bar phase offset so the bars dance rather than move in lockstep
                const h = Math.max(0.15, level * (0.6 + 0.4 * Math.sin(Date.now() / 120 + i * 1.3)));
                bars[i].style.height = `${h * 100}%`;
            }
        }
    }, 80);
}

function stopVisualLoop() {
    if (visualTimer) clearInterval(visualTimer);
    visualTimer = null;
    micMeterFillEl.style.width = "0%";
    renderLedWall(0, "idle");
}

// ── Conversation history (localStorage) ─────────────────────────────────────
function loadHistory() {
    try {
        const raw = localStorage.getItem(HISTORY_KEY);
        if (!raw) return [];
        const arr = JSON.parse(raw);
        return Array.isArray(arr) ? arr.slice(-HISTORY_MAX) : [];
    } catch (e) { return []; }
}

function persistHistory() {
    try {
        localStorage.setItem(HISTORY_KEY, JSON.stringify(history.slice(-HISTORY_MAX)));
    } catch (e) { /* storage full or unavailable */ }
}

let history = loadHistory();

const DELIVERY_MARKERS = /\[(?:appreciative|calm|concerned|curious|encouraging|excited|happy|joking|quiet|reassuring|reflective|sad|serious|surprised|sympathetic|urgent|whispering|laughter|sighing|breathing|neutral)\]\s*/gi;

function cleanSpokenText(text) {
    return String(text || "").replace(DELIVERY_MARKERS, "").trim();
}

function formatTimestamp(ts) {
    if (!ts) return "";
    return new Date(ts).toLocaleTimeString([], { hour: "numeric", minute: "2-digit" });
}

function renderMessage(msg) {
    const wrap = document.createElement("div");
    wrap.className = `message-row ${msg.role}`;
    wrap.dataset.ts = formatTimestamp(msg.ts);

    if (msg.role === "agent") {
        const dot = document.createElement("span");
        dot.className = "avatar-dot";
        wrap.appendChild(dot);
    }

    const bubble = document.createElement("div");
    bubble.className = "bubble";
    bubble.textContent = cleanSpokenText(msg.text);
    if (msg.role === "agent") {
        const viz = document.createElement("span");
        viz.className = "audio-viz";
        for (let i = 0; i < 5; i++) viz.appendChild(document.createElement("i"));
        bubble.appendChild(viz);
    }
    wrap.appendChild(bubble);
    messagesEl.appendChild(wrap);
    messagesEl.scrollTop = messagesEl.scrollHeight;
}

function addMessage(role, text) {
    clearPartials();
    const msg = { role, text, ts: Date.now() };
    history.push(msg);
    persistHistory();
    renderMessage(msg);
    return msg;
}

// Partial transcripts render greyed and update in place until a final arrives.
function addPartial(role, text) {
    const rows = messagesEl.querySelectorAll(".message-row.partial");
    let last = null;
    for (const r of rows) last = r;
    if (last && last.dataset.role === role) {
        last.querySelector(".bubble").textContent = cleanSpokenText(text);
        messagesEl.scrollTop = messagesEl.scrollHeight;
        return;
    }
    const wrap = document.createElement("div");
    wrap.className = `message-row ${role} partial`;
    wrap.dataset.role = role;
    if (role === "agent") {
        const dot = document.createElement("span");
        dot.className = "avatar-dot";
        wrap.appendChild(dot);
    }
    const bubble = document.createElement("div");
    bubble.className = "bubble partial";
    bubble.textContent = cleanSpokenText(text);
    wrap.appendChild(bubble);
    messagesEl.appendChild(wrap);
    messagesEl.scrollTop = messagesEl.scrollHeight;
}

function clearPartials() {
    messagesEl.querySelectorAll(".message-row.partial").forEach((el) => el.remove());
}

function renderHistory() {
    messagesEl.innerHTML = "";
    for (const msg of history) renderMessage(msg);
    messagesEl.scrollTop = messagesEl.scrollHeight;
}

clearBtn.addEventListener("click", () => {
    history = [];
    persistHistory();
    clearPartials();
    renderHistory();
});

renderHistory();

// ── Transcripts ─────────────────────────────────────────────────────────────
// Primary: livekit-agents built-in text stream (word-by-word when available).
function registerTranscriptionStream(rm) {
    try {
        rm.registerTextStreamHandler("lk.transcription", async (reader, participantInfo) => {
            const text = await reader.readAll();
            if (!text || !text.trim()) return;
            const attrs = (reader.info && reader.info.attributes) || {};
            const trackId = attrs["lk.transcribed_track_id"] || "";
            // Distinguish user vs agent by the transcribed track's owner.
            let role = "agent";
            if (participantInfo && participantInfo.identity === AGENT_NAME) {
                role = "agent";
            } else if (trackId) {
                for (const p of rm.remoteParticipants.values()) {
                    const pub = p.getTrackPublication(trackId);
                    if (pub) { role = isAgent(p) ? "agent" : "user"; break; }
                }
            }
            // Use partial rendering: updates the same row in place until final.
            addPartial(role, text.trim());
        });
    } catch (e) {
        // Older SDKs may not support registerTextStreamHandler — the data
        // channel handler below still covers transcripts.
        console.warn("text stream registration failed:", e);
    }
}

// Secondary: agent publishes {type:"transcript"} on topic "transcript".
function handleDataPacket(payload, participant, topic) {
    try {
        const msg = JSON.parse(new TextDecoder().decode(payload));
        if (msg.type === "agent_ready") {
            agentReady = true;
        } else if (msg.type === "transcript") {
            addMessage(msg.role || "agent", msg.text);
            if ((msg.role || "agent") === "agent") {
                if (conversationMode === "text") {
                    setState("listening");
                    chatInput.focus();
                } else if (uiState === "thinking") {
                    // Text arrives even when headless playback or an analyser is
                    // unavailable; use it to release the thinking state.
                    setState("speaking");
                }
            }
        } else if (msg.type === "task_event") {
            handleTaskEvent(msg);
        } else if (msg.type === "models") {
            availableModels = Array.isArray(msg.models) ? msg.models : [];
            // Don't clobber a saved preference — the agent acks the applied
            // model separately via model_changed.
            if (!selectedModel && msg.selected) selectedModel = msg.selected;
            renderModelList();
        } else if (msg.type === "model_changed") {
            if (msg.model) {
                selectedModel = msg.model;
                localStorage.setItem(MODEL_KEY, selectedModel);
                renderModelList();
            }
        }
        // set_voice/set_model messages flow the other way; nothing else to do client-side.
    } catch (e) {
        console.warn("bad data packet", e);
    }
}

// ── Voice settings sheet ────────────────────────────────────────────────────
function currentVoiceId() {
    const saved = localStorage.getItem("preferred_voice");
    return VOICES.some((v) => v.id === saved) ? saved : VOICES[0].id;
}

function renderVoiceList() {
    voiceListEl.innerHTML = "";
    const active = currentVoiceId();
    for (const v of VOICES) {
        const card = document.createElement("div");
        card.className = "voice-card" + (v.id === active ? " active" : "");
        card.dataset.voice = v.id;

        const name = document.createElement("span");
        name.className = "voice-name";
        name.textContent = v.name + (v.tag ? ` (${v.tag})` : "");

        const selected = v.id === active;
        card.setAttribute("role", "radio");
        card.setAttribute("aria-checked", String(selected));
        card.tabIndex = 0;
        card.appendChild(name);
        card.addEventListener("click", () => selectVoice(v.id));
        card.addEventListener("keydown", (event) => {
            if (event.key === "Enter" || event.key === " ") {
                event.preventDefault();
                selectVoice(v.id);
            }
        });
        voiceListEl.appendChild(card);
    }
}

function selectVoice(voiceId) {
    localStorage.setItem("preferred_voice", voiceId);
    renderVoiceList();
    if (room && agentParticipant) {
        sendVoiceMessage(voiceId);
        const v = VOICES.find((x) => x.id === voiceId);
        addMessage("system", `Voice changed to ${v ? v.name : voiceId}`);
    }
}

// ── Model (brain) settings ──────────────────────────────────────────────────
function currentModelId() {
    if (availableModels.length === 0) return selectedModel;
    if (selectedModel && availableModels.includes(selectedModel)) return selectedModel;
    return availableModels[0];
}

function renderModelList() {
    modelListEl.innerHTML = "";
    if (!availableModels.length) {
        modelNoteEl.hidden = false;
        modelNoteEl.textContent = room
            ? "Loading available models…"
            : "Start a conversation to load the model list.";
        return;
    }
    modelNoteEl.hidden = true;
    const active = currentModelId();
    for (const id of availableModels) {
        const card = document.createElement("div");
        card.className = "voice-card" + (id === active ? " active" : "");
        card.dataset.model = id;
        card.setAttribute("role", "radio");
        card.setAttribute("aria-checked", String(id === active));
        card.tabIndex = 0;

        const name = document.createElement("span");
        name.className = "voice-name";
        name.textContent = id;

        card.appendChild(name);
        card.addEventListener("click", () => selectModel(id));
        card.addEventListener("keydown", (event) => {
            if (event.key === "Enter" || event.key === " ") {
                event.preventDefault();
                selectModel(id);
            }
        });
        modelListEl.appendChild(card);
    }
}

function selectModel(modelId) {
    selectedModel = modelId;
    localStorage.setItem(MODEL_KEY, modelId);
    renderModelList();
    if (room && agentParticipant) {
        sendModelMessage(modelId);
        addMessage("system", `Brain changed to ${modelId}`);
    }
}

function openSheet() {
    renderVoiceList();
    renderModelList();
    sheetBackdrop.hidden = false;
    settingsSheet.classList.add("open");
    settingsBtn.setAttribute("aria-expanded", "true");
    settingsSheet.querySelector(".voice-card")?.focus();
}

function closeSheet() {
    settingsSheet.classList.remove("open");
    settingsBtn.setAttribute("aria-expanded", "false");
    window.setTimeout(() => { sheetBackdrop.hidden = true; }, 240);
    settingsBtn.focus();
}

settingsBtn.setAttribute("aria-expanded", "false");
settingsBtn.addEventListener("click", openSheet);
closeSheetBtn.addEventListener("click", closeSheet);
sheetBackdrop.addEventListener("click", closeSheet);
document.addEventListener("keydown", (event) => {
    if (event.key !== "Escape") return;
    if (settingsSheet.classList.contains("open")) closeSheet();
    if (tasksPanel.classList.contains("open")) setTasksOpen(false);
});
// ── Wake lock ───────────────────────────────────────────────────────────────
async function acquireWakeLock() {
    try {
        if ("wakeLock" in navigator) {
            wakeLock = await navigator.wakeLock.request("screen");
        }
    } catch (e) { /* not critical */ }
}

function releaseWakeLock() {
    if (wakeLock) {
        wakeLock.release().catch(() => {});
        wakeLock = null;
    }
}

// ── Agent detection ─────────────────────────────────────────────────────────
// The agent may already be in the room before we join (it persists between
// page loads), so scan remoteParticipants after connect AND watch for new
// joins — ParticipantConnected does not fire for pre-existing participants.
function isAgent(participant) {
    // kind is the numeric proto enum; ParticipantKind.AGENT === 4.
    // Prefer the SDK's own getter where available.
    if (participant.isAgent !== undefined && participant.isAgent !== null) {
        return participant.isAgent;
    }
    return participant.identity === AGENT_NAME
        || participant.kind === LivekitClient.ParticipantKind.AGENT;
}

function findAgent(rm) {
    if (!rm) return null;
    for (const p of rm.remoteParticipants.values()) {
        if (isAgent(p)) return p;
    }
    return null;
}

function markAgentFound(rm, participant) {
    agentParticipant = participant;
    statusEl.textContent = conversationMode === "text"
        ? "Hope joined · Text chat ready"
        : "Hope joined · Preparing microphone…";
    // Synchronize voice, brain and interaction mode when the agent joins.
    sendVoiceMessage(currentVoiceId(), rm);
    if (selectedModel) sendModelMessage(selectedModel, rm);
    sendModeMessage(conversationMode, rm);
}

function createRoom(token) {
    const newRoom = new Room({
        adaptiveStream: true,
        dynacast: true,
    });

    // Listen for the agent joining after us
    newRoom.on(RoomEvent.ParticipantConnected, (participant) => {
        if (isAgent(participant)) markAgentFound(newRoom, participant);
    });

    // Attach and play incoming audio tracks (agent TTS)
    newRoom.on(RoomEvent.TrackSubscribed, (track, publication, participant) => {
        if (track.kind === LivekitClient.Track.Kind.Audio) {
            const el = track.attach();
            el.id = `audio-${participant.identity}`;
            document.body.appendChild(el);
            // Remote audio analyser drives the orb + visualizer while speaking
            setupRemoteAudioAnalyser(el);
        }
    });

    newRoom.on(RoomEvent.TrackUnsubscribed, (track) => {
        track.detach().forEach((el) => el.remove());
    });

    // Browsers block audio playback until a user gesture; show an unlock
    // button if the page loads without one.
    newRoom.on(RoomEvent.AudioPlaybackStatusChanged, () => {
        if (!newRoom.canPlaybackAudio) {
            const existing = document.getElementById("audioUnlockBtn");
            if (!existing) {
                const btn = document.createElement("button");
                btn.id = "audioUnlockBtn";
                btn.className = "btn btn-primary";
                btn.textContent = "Tap to enable audio";
                btn.style.cssText = "position:fixed;bottom:2rem;left:50%;transform:translateX(-50%);z-index:999;padding:1rem 2rem;font-size:1.1rem;border-radius:999px;box-shadow:0 4px 24px rgba(0,0,0,.5)";
                btn.onclick = () => { newRoom.startAudio(); btn.remove(); };
                document.body.appendChild(btn);
            }
        } else {
            const existing = document.getElementById("audioUnlockBtn");
            if (existing) existing.remove();
        }
    });

    // Live text stream (word-by-word transcripts)
    registerTranscriptionStream(newRoom);

    // Data channel: transcripts (secondary source) + voice control
    newRoom.on(RoomEvent.DataReceived, (payload, participant, kind, topic) => {
        handleDataPacket(payload, participant, topic);
    });

    // Guard with `=== room` so a stale (retry-discarded) connection cannot
    // clobber UI state of the active one.
    newRoom.on(RoomEvent.ConnectionQualityChanged, (participant, quality) => {
        if (participant === newRoom.localParticipant && newRoom === room) {
            statusEl.textContent = `Secure room · ${quality} connection`;
        }
    });

    newRoom.on(RoomEvent.Disconnected, () => {
        if (newRoom !== room) return;
        teardownAudio();
        stopVisualLoop();
        releaseWakeLock();
        statusEl.textContent = "Conversation ended";
        setState("idle");
        startBtn.disabled = false;
        stopBtn.disabled = true;
        agentParticipant = null;
        agentReady = false;
    });

    return newRoom.connect(LIVEKIT_URL, token, {
        autoSubscribe: true,
    }).then(() => {
        // Pick up an agent that was already in the room before we joined
        const existing = findAgent(newRoom);
        if (existing) markAgentFound(newRoom, existing);
        return newRoom;
    });
}

function waitForAgentReady(timeoutMs) {
    return new Promise((resolve) => {
        if (agentReady) return resolve(true);
        const deadline = Date.now() + timeoutMs;
        const timer = setInterval(() => {
            if (agentReady) {
                clearInterval(timer);
                resolve(true);
            } else if (Date.now() > deadline) {
                clearInterval(timer);
                resolve(false);
            }
        }, 100);
    });
}

function waitForAgent(timeoutMs) {
    return new Promise((resolve) => {
        if (findAgent(room)) return resolve(true);
        const deadline = Date.now() + timeoutMs;
        const timer = setInterval(() => {
            const found = findAgent(room);
            if (found) {
                if (!agentParticipant) markAgentFound(room, found);
                clearInterval(timer);
                resolve(true);
            } else if (Date.now() > deadline) {
                clearInterval(timer);
                resolve(false);
            }
        }, 250);
    });
}

async function connectConversation() {
    if (room && agentParticipant) return room;
    if (connectionPromise) return connectionPromise;

    connectionPromise = (async () => {
        try {
            setState("connecting");
            statusEl.textContent = "Opening your secure room…";
            await acquireWakeLock();

            // Get a signed access token from the token endpoint.
            const tokenData = await fetchToken(ROOM_NAME);
            room = await createRoom(tokenData.token);

            // The agent is dispatched when we join. If it misses the dispatch
            // (for example during a server restart), reconnect once.
            statusEl.textContent = "Inviting Hope into the room…";
            if (!(await waitForAgent(10000))) {
                statusEl.textContent = "Hope is taking a moment · Retrying…";
                const stale = room;
                room = null;
                agentParticipant = null;
                agentReady = false;
                await stale.disconnect();
                const freshTokenData = await fetchToken(ROOM_NAME);
                room = await createRoom(freshTokenData.token);
                if (!(await waitForAgent(15000))) {
                    throw new Error("Assistant did not join — reload the page and try again");
                }
            }
            statusEl.textContent = "Hope joined · Finishing setup…";
            if (!(await waitForAgentReady(10000))) {
                throw new Error("Assistant joined but was not ready — try again");
            }

            sendModeMessage(conversationMode);
            if (conversationMode === "voice") {
                await room.startAudio();
                statusEl.textContent = "Waiting for microphone permission…";
                await room.localParticipant.setMicrophoneEnabled(true);
                micMuted = false;
                setupMicAnalyser();
                startVisualLoop();
                statusEl.textContent = "Secure room · Microphone on";
            } else {
                await room.localParticipant.setMicrophoneEnabled(false);
                micMuted = true;
                stopVisualLoop();
                statusEl.textContent = "Secure room · Text mode";
            }

            startBtn.disabled = true;
            stopBtn.disabled = false;
            muteBtn.disabled = conversationMode !== "voice";
            updateMuteIcon();
            setState("listening");
            return room;
        } catch (err) {
            console.error("Connection failed:", err);
            statusEl.textContent = `Error: ${err.message}`;
            setState("idle");
            releaseWakeLock();
            throw err;
        } finally {
            connectionPromise = null;
        }
    })();

    return connectionPromise;
}

startBtn.addEventListener("click", () => {
    connectConversation().catch(() => {});
});

// ── Text chat ──────────────────────────────────────────────────────────────
function resizeChatInput() {
    chatInput.style.height = "auto";
    chatInput.style.height = `${Math.min(chatInput.scrollHeight, 144)}px`;
}

chatInput.addEventListener("input", () => {
    resizeChatInput();
    sendChatBtn.disabled = !chatInput.value.trim();
});

chatInput.addEventListener("keydown", (event) => {
    if (event.key === "Enter" && !event.shiftKey) {
        event.preventDefault();
        chatComposer.requestSubmit();
    }
});

chatComposer.addEventListener("submit", async (event) => {
    event.preventDefault();
    const text = chatInput.value.trim();
    if (!text) return;

    sendChatBtn.disabled = true;
    chatInput.disabled = true;
    try {
        if (conversationMode !== "text") await setConversationMode("text");
        await connectConversation();
        setState("thinking");
        await room.localParticipant.sendText(text, { topic: "lk.chat" });
        chatInput.value = "";
        resizeChatInput();
    } catch (err) {
        console.error("Text message failed:", err);
        statusEl.textContent = `Message not sent: ${err.message}`;
        setState("listening");
    } finally {
        chatInput.disabled = false;
        sendChatBtn.disabled = !chatInput.value.trim();
        chatInput.focus();
    }
});

// ── Stop ────────────────────────────────────────────────────────────────────
stopBtn.addEventListener("click", () => {
    if (room) {
        room.disconnect();
        room = null;
        agentParticipant = null;
        agentReady = false;
    }
    teardownAudio();
    stopVisualLoop();
    releaseWakeLock();
    document.querySelectorAll('[id^="audio-"]').forEach(el => el.remove());
    statusEl.textContent = "Conversation ended";
    setState("idle");
    startBtn.disabled = false;
    stopBtn.disabled = true;
    muteBtn.disabled = true;
    micMuted = false;
    updateMuteIcon();
});

// ── Mic mute toggle ─────────────────────────────────────────────────────────
muteBtn.addEventListener("click", async () => {
    if (!room || !room.localParticipant) return;
    const nextMuted = !micMuted;
    try {
        await room.localParticipant.setMicrophoneEnabled(!nextMuted);
        micMuted = nextMuted;
        updateMuteIcon();
    } catch (err) {
        console.warn("Microphone toggle failed:", err);
        statusEl.textContent = "Microphone unavailable in this browser";
    }
});

function updateMuteIcon() {
    const muted = muteBtn.classList.toggle("muted", micMuted);
    muteBtn.setAttribute("aria-label", muted ? "Unmute microphone" : "Mute microphone");
    muteBtn.title = muted ? "Unmute microphone" : "Mute microphone";
}

// ── Helper: fetch a signed access token from the token endpoint ────────────
async function fetchToken(roomName) {
    const resp = await fetch("/token", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ room: roomName }),
    });
    if (!resp.ok) throw new Error(`Token endpoint returned ${resp.status}`);
    const data = await resp.json();
    return { token: data.token, room: data.room || null };
}

// ── Helper: send voice selection to the agent via data channel ─────────────
function sendVoiceMessage(voice, targetRoom) {
    const r = targetRoom || room;
    if (!r || !r.localParticipant) return;
    const payload = new TextEncoder().encode(JSON.stringify({ type: "set_voice", voice }));
    r.localParticipant.publishData(payload, {
        topic: "voice-control",
        reliable: true,
    });
}

function sendModeMessage(mode, targetRoom) {
    const r = targetRoom || room;
    if (!r || !r.localParticipant) return;
    const payload = new TextEncoder().encode(JSON.stringify({ type: "set_mode", mode }));
    r.localParticipant.publishData(payload, {
        topic: "conversation-control",
        reliable: true,
    });
}

// ── Helper: send model selection to the agent via data channel ─────────────
function sendModelMessage(model, targetRoom) {
    const r = targetRoom || room;
    if (!r || !r.localParticipant || !model) return;
    const payload = new TextEncoder().encode(JSON.stringify({ type: "set_model", model }));
    r.localParticipant.publishData(payload, {
        topic: "voice-control",
        reliable: true,
    });
}

buildLedWall();