// ==UserScript==
// @name         12345 AI Native Element Copilot
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  Native-track bridge with fixed element selection: element-2:audio input, element-0:video vision.
// @author       You
// @match        *://yhy-yw.22sj.cn:*/*
// @grant        none
// @run-at       document-start
// ==/UserScript==

(function () {
    'use strict';

    const DEFAULT_SIGNALING_URL = 'ws://182.92.86.220:8000/ws/voice';
    const STATIC_AUDIO_ELEMENT_REASON = 'element-2:audio';
    const STATIC_VIDEO_ELEMENT_REASON = 'element-0:video';

    const originalAddEventListener = RTCPeerConnection.prototype.addEventListener;
    const originalAddTrack = RTCPeerConnection.prototype.addTrack;
    const originalAddTransceiver = RTCPeerConnection.prototype.addTransceiver;
    const originalSetRemoteDescription = RTCPeerConnection.prototype.setRemoteDescription;
    const mediaSrcObjectDescriptor = Object.getOwnPropertyDescriptor(HTMLMediaElement.prototype, 'srcObject');

    const remoteAudio = new Map();
    const remoteVideo = new Map();
    const businessSenders = new Map();
    const aiOutputTrackIds = new Set();
    const inboundMemory = new Map();
    const outboundMemory = new Map();
    const internalPcs = new WeakSet();
    const AUDIO_UPLINK_STORAGE_KEY = 'element-copilot-send-audio';
    const VIDEO_UPLINK_STORAGE_KEY = 'element-copilot-send-video';

    let selectedRemoteAudio = null;
    let selectedRemoteVideo = null;
    let selectedBusinessSender = null;
    let originalBusinessTrack = null;
    let aiAudioTrack = null;

    let aiPc = null;
    let aiWs = null;
    let aiDc = null;
    let aiAudioSender = null;
    let aiVideoSender = null;
    let isAiTakeover = false;
    let aiAttached = false;
    let inputVu = 0;
    let outputVu = 0;
    let inputHealthTimer = null;
    let outputHealthTimer = null;
    let assistantLine = null;
    let assistantBuffer = '';
    let inputRecorder = null;
    let inputRecordingChunks = [];
    let inputRecordingTrack = null;
    let inputRecordingStartedAt = 0;

    function log(message) {
        console.log(`[AI Native Element] ${message}`);
    }

    function readBoolSetting(key, fallback) {
        try {
            const value = localStorage.getItem(key);
            if (value === null) return fallback;
            return value === 'true';
        } catch {
            return fallback;
        }
    }

    function writeBoolSetting(key, value) {
        try {
            localStorage.setItem(key, value ? 'true' : 'false');
        } catch {
            // Ignore storage failures; the current checkbox state still applies.
        }
    }

    function shouldSendAudioToAi() {
        return readBoolSetting(AUDIO_UPLINK_STORAGE_KEY, true);
    }

    function shouldSendVideoToAi() {
        return readBoolSetting(VIDEO_UPLINK_STORAGE_KEY, true);
    }

    function appendChatLine(role, text, important = false) {
        const box = document.getElementById('element-copilot-log');
        if (!box) return;
        if (box.children.length === 1 && box.children[0].dataset.placeholder) box.innerHTML = '';
        const row = document.createElement('div');
        row.textContent = `[${new Date().toLocaleTimeString([], { hour12: false })}] ${role}: ${text}`;
        row.style.marginBottom = '4px';
        if (important) row.style.color = '#fcd34d';
        box.appendChild(row);
        while (box.children.length > 120) box.removeChild(box.firstChild);
        box.scrollTop = box.scrollHeight;
        return row;
    }

    function startAssistantLine() {
        assistantBuffer = '';
        assistantLine = null;
    }

    function appendAssistantDelta(delta) {
        if (!delta) return;
        const box = document.getElementById('element-copilot-log');
        if (!box) {
            console.log(`[AI Native Element] AI: ${delta}`);
            return;
        }
        if (box.children.length === 1 && box.children[0].dataset.placeholder) box.innerHTML = '';
        if (!assistantLine) assistantLine = appendChatLine('AI', '');
        assistantBuffer += delta;
        assistantLine.textContent = `[${new Date().toLocaleTimeString([], { hour12: false })}] AI: ${assistantBuffer}`;
        box.scrollTop = box.scrollHeight;
    }

    function finishAssistantLine() {
        assistantLine = null;
        assistantBuffer = '';
    }

    function logUserTranscript(text) {
        if (!text?.trim()) return;
        finishAssistantLine();
        appendChatLine('用户', text.trim(), true);
    }

    function recorderMimeType() {
        if (window.MediaRecorder?.isTypeSupported?.('audio/webm;codecs=opus')) return 'audio/webm;codecs=opus';
        if (window.MediaRecorder?.isTypeSupported?.('audio/webm')) return 'audio/webm';
        return '';
    }

    function recordingFileName(track) {
        const stamp = new Date().toISOString().replace(/[:.]/g, '-');
        const trackPart = track?.id ? track.id.slice(0, 8) : 'no-track';
        return `ai-input-${trackPart}-${stamp}.webm`;
    }

    async function startInputRecording() {
        if (inputRecorder?.state === 'recording') return;
        selectRemoteAudio('record');
        if (!isLive(selectedRemoteAudio)) {
            appendChatLine('录音', `没有可录制的 ${STATIC_AUDIO_ELEMENT_REASON} 音轨`, true);
            return;
        }
        if (!window.MediaRecorder) {
            appendChatLine('录音', '当前浏览器不支持 MediaRecorder', true);
            return;
        }

        inputRecordingChunks = [];
        inputRecordingTrack = selectedRemoteAudio;
        inputRecordingStartedAt = Date.now();
        const stream = new MediaStream([selectedRemoteAudio]);
        const mimeType = recorderMimeType();
        inputRecorder = new MediaRecorder(stream, mimeType ? { mimeType } : undefined);
        inputRecorder.ondataavailable = (event) => {
            if (event.data?.size > 0) inputRecordingChunks.push(event.data);
        };
        inputRecorder.onstop = () => {
            const blob = new Blob(inputRecordingChunks, { type: inputRecorder?.mimeType || 'audio/webm' });
            const url = URL.createObjectURL(blob);
            const link = document.createElement('a');
            link.href = url;
            link.download = recordingFileName(inputRecordingTrack);
            document.body.appendChild(link);
            link.click();
            link.remove();
            setTimeout(() => URL.revokeObjectURL(url), 30000);

            const seconds = ((Date.now() - inputRecordingStartedAt) / 1000).toFixed(1);
            appendChatLine('录音', `已保存 ${link.download}（${seconds}s，${(blob.size / 1024).toFixed(1)} KB）`, true);
            inputRecorder = null;
            inputRecordingChunks = [];
            inputRecordingTrack = null;
            updateRecordButton();
        };
        inputRecorder.start(250);
        appendChatLine('录音', `开始录制 AI 输入：${trackLabel(inputRecordingTrack)}`, true);
        updateRecordButton();
    }

    function stopInputRecording() {
        if (inputRecorder?.state === 'recording') inputRecorder.stop();
    }

    function toggleInputRecording() {
        if (inputRecorder?.state === 'recording') stopInputRecording();
        else startInputRecording();
    }

    function updateRecordButton() {
        const button = document.getElementById('element-copilot-record');
        if (!button) return;
        const recording = inputRecorder?.state === 'recording';
        button.textContent = recording ? '停止录制 AI 输入' : '录制 AI 输入';
        button.style.background = recording ? '#dc2626' : '#2563eb';
    }

    function pcId() {
        const bytes = new Uint8Array(16);
        crypto.getRandomValues(bytes);
        return 'PC-' + Array.from(bytes).map((b) => b.toString(16).padStart(2, '0')).join('');
    }

    function isInternalPc(pc) {
        return Boolean(pc && (pc.__aiNativeElementInternal || internalPcs.has(pc) || pc === aiPc));
    }

    function isLive(track) {
        return track && track.readyState === 'live';
    }

    function trackLabel(track) {
        if (!track) return 'none';
        return `${track.id}${track.muted ? ' muted' : ''}`;
    }

    function markInternalPc(pc) {
        if (!pc) return;
        pc.__aiNativeElementInternal = true;
        internalPcs.add(pc);
    }

    function elementReasonFor(element) {
        if (!element) return null;
        const tag = element.tagName?.toLowerCase();
        if (tag !== 'audio' && tag !== 'video') return null;
        const elements = Array.from(document.querySelectorAll(tag));
        const index = elements.indexOf(element);
        if (index < 0) return `${tag}-srcObject`;
        return `element-${index}:${tag}`;
    }

    function hasElementReason(item, reason) {
        return Boolean(item?.reasons?.has(reason));
    }

    function rememberRemoteReceiver(receiver, reason) {
        const track = receiver?.track;
        if (!isLive(track) || isInternalPc(receiver?.transport)) return;

        if (track.kind === 'audio' && !aiOutputTrackIds.has(track.id)) {
            let item = remoteAudio.get(track.id);
            if (!item) {
                item = { track, receiver, reasons: new Set(), bytesDelta: 0, packetsDelta: 0 };
                remoteAudio.set(track.id, item);
                log(`audio candidate ${trackLabel(track)} (${reason})`, true);
            }
            item.track = track;
            item.receiver = receiver || item.receiver;
            item.reasons.add(reason);
            selectRemoteAudio(reason);
        }

        if (track.kind === 'video') {
            let item = remoteVideo.get(track.id);
            if (!item) {
                item = { track, receiver, reasons: new Set() };
                remoteVideo.set(track.id, item);
                log(`video candidate ${trackLabel(track)} (${reason})`, true);
            }
            item.track = track;
            item.receiver = receiver || item.receiver;
            item.reasons.add(reason);
            selectRemoteVideo(reason);
        }
    }

    function rememberRemoteStream(stream, reason) {
        if (!stream || !(stream instanceof MediaStream)) return;
        for (const track of stream.getAudioTracks()) {
            if (aiOutputTrackIds.has(track.id)) continue;
            let item = remoteAudio.get(track.id);
            if (!item) {
                item = { track, receiver: null, reasons: new Set(), bytesDelta: 0, packetsDelta: 0 };
                remoteAudio.set(track.id, item);
                log(`audio stream candidate ${trackLabel(track)} (${reason})`, true);
            }
            item.track = track;
            item.reasons.add(reason);
        }
        for (const track of stream.getVideoTracks()) {
            let item = remoteVideo.get(track.id);
            if (!item) {
                item = { track, receiver: null, reasons: new Set() };
                remoteVideo.set(track.id, item);
                log(`video stream candidate ${trackLabel(track)} (${reason})`, true);
            }
            item.track = track;
            item.reasons.add(reason);
        }
        selectRemoteAudio(reason);
        selectRemoteVideo(reason);
    }

    function selectRemoteAudio(reason) {
        const current = selectedRemoteAudio && remoteAudio.get(selectedRemoteAudio.id);
        if (isLive(selectedRemoteAudio) && !selectedRemoteAudio.muted && hasElementReason(current, STATIC_AUDIO_ELEMENT_REASON)) {
            return selectedRemoteAudio;
        }

        const item = Array.from(remoteAudio.values()).find((candidate) => (
            isLive(candidate.track)
            && !candidate.track.muted
            && hasElementReason(candidate, STATIC_AUDIO_ELEMENT_REASON)
        ));
        if (!item) return null;

        if (selectedRemoteAudio !== item.track) {
            selectedRemoteAudio = item.track;
            log(`selected input audio (${reason}) from ${STATIC_AUDIO_ELEMENT_REASON}: ${trackLabel(selectedRemoteAudio)}`, true);
            attachAudioToAi();
        }
        return selectedRemoteAudio;
    }

    function selectRemoteVideo(reason) {
        const current = selectedRemoteVideo && remoteVideo.get(selectedRemoteVideo.id);
        if (isLive(selectedRemoteVideo) && !selectedRemoteVideo.muted && hasElementReason(current, STATIC_VIDEO_ELEMENT_REASON)) {
            return selectedRemoteVideo;
        }

        const item = Array.from(remoteVideo.values()).find((candidate) => (
            isLive(candidate.track)
            && !candidate.track.muted
            && hasElementReason(candidate, STATIC_VIDEO_ELEMENT_REASON)
        ));
        if (!item) return null;

        if (selectedRemoteVideo !== item.track) {
            selectedRemoteVideo = item.track;
            log(`selected input video (${reason}) from ${STATIC_VIDEO_ELEMENT_REASON}: ${trackLabel(selectedRemoteVideo)}`, true);
            attachVideoToAi();
        }
        return selectedRemoteVideo;
    }

    function rememberBusinessSender(sender, track, reason) {
        if (!sender) return;
        const senderTrack = track || sender.track;
        if (senderTrack && senderTrack.kind !== 'audio') return;

        const id = sender.__aiNativeElementSenderId || `sender-${businessSenders.size + 1}`;
        sender.__aiNativeElementSenderId = id;

        let item = businessSenders.get(id);
        if (!item) {
            item = { id, sender, track: senderTrack || null, originalTrack: senderTrack || null, sources: new Set(), bytesDelta: 0, packetsDelta: 0 };
            businessSenders.set(id, item);
            log(`business sender candidate ${id} (${reason}): ${trackLabel(senderTrack)}`, true);
        }
        item.sender = sender;
        item.track = sender.track || senderTrack || item.track;
        if (!isAiTakeover && senderTrack && senderTrack !== aiAudioTrack) item.originalTrack = senderTrack;
        item.sources.add(reason);
        wrapBusinessSender(sender);
        selectBusinessSender(reason);
    }

    function wrapBusinessSender(sender) {
        if (!sender || sender.__aiNativeElementWrapped) return;
        const originalReplaceTrack = sender.replaceTrack?.bind(sender);
        if (!originalReplaceTrack) return;

        sender.replaceTrack = async function (track) {
            const result = await originalReplaceTrack(track);
            rememberBusinessSender(sender, track, 'replaceTrack');
            return result;
        };
        sender.__aiNativeElementWrapped = true;
    }

    function isRemoteInputTrack(track) {
        return Boolean(track && remoteAudio.has(track.id) && !aiOutputTrackIds.has(track.id));
    }

    function selectBusinessSender(reason) {
        if (selectedBusinessSender && !isRemoteInputTrack(selectedBusinessSender.track)) return selectedBusinessSender;

        const item = Array.from(businessSenders.values()).find((candidate) => {
            const track = candidate.sender.track || candidate.track || candidate.originalTrack;
            return candidate.sources.has('pc-addTrack') && !isRemoteInputTrack(track);
        });
        if (!item) return null;

        selectedBusinessSender = item.sender;
        originalBusinessTrack = item.originalTrack || item.sender.track || originalBusinessTrack;
        log(`selected output sender (${reason}): ${item.id}, track=${trackLabel(item.sender.track)}`, true);
        attachAiOutputToBusiness();
        return selectedBusinessSender;
    }

    function setVu(id, level) {
        const el = document.getElementById(id);
        if (el) el.style.width = `${Math.min(100, level * 2500)}%`;
    }

    function renderVu() {
        inputVu *= 0.88;
        outputVu *= 0.88;
        setVu('element-copilot-input-vu', inputVu);
        setVu('element-copilot-output-vu', outputVu);
        requestAnimationFrame(renderVu);
    }

    async function refreshStats() {
        await refreshInputStats();
        await refreshOutputStats();
    }

    async function refreshInputStats() {
        for (const item of remoteAudio.values()) {
            if (!item.receiver?.getStats) continue;
            const report = await item.receiver.getStats();
            report.forEach((stat) => {
                const kind = stat.kind || stat.mediaType;
                if (stat.type !== 'inbound-rtp' || kind !== 'audio') return;
                const prev = inboundMemory.get(stat.id);
                const bytes = stat.bytesReceived || 0;
                const packets = stat.packetsReceived || 0;
                item.bytesReceived = bytes;
                item.packetsReceived = packets;
                item.bytesDelta = prev ? Math.max(0, bytes - prev.bytes) : 0;
                item.packetsDelta = prev ? Math.max(0, packets - prev.packets) : 0;
                inboundMemory.set(stat.id, { bytes, packets });
                if (item.track === selectedRemoteAudio) {
                    inputVu = Math.max(inputVu, Math.min(0.12, item.bytesDelta / 12000), Math.min(0.04, item.packetsDelta / 500));
                }
            });
        }
    }

    async function refreshOutputStats() {
        for (const item of businessSenders.values()) {
            if (!item.sender?.getStats) continue;
            item.track = item.sender.track || item.track;
            const report = await item.sender.getStats();
            report.forEach((stat) => {
                const kind = stat.kind || stat.mediaType;
                if (stat.type !== 'outbound-rtp' || kind !== 'audio') return;
                const key = `${item.id}:${stat.id}`;
                const prev = outboundMemory.get(key);
                const bytes = stat.bytesSent || 0;
                const packets = stat.packetsSent || 0;
                item.bytesSent = bytes;
                item.packetsSent = packets;
                item.bytesDelta = prev ? Math.max(0, bytes - prev.bytes) : 0;
                item.packetsDelta = prev ? Math.max(0, packets - prev.packets) : 0;
                outboundMemory.set(key, { bytes, packets });
                if (item.sender === selectedBusinessSender) {
                    outputVu = Math.max(outputVu, Math.min(0.12, item.bytesDelta / 12000), Math.min(0.04, item.packetsDelta / 500));
                }
            });
        }
    }

    async function outboundBytes(sender) {
        if (!sender?.getStats) return null;
        let total = 0;
        const report = await sender.getStats();
        report.forEach((stat) => {
            const kind = stat.kind || stat.mediaType;
            if (stat.type === 'outbound-rtp' && kind === 'audio') total += stat.bytesSent || 0;
        });
        return total;
    }

    function aiState() {
        if (!aiPc) return 'pc=null';
        return `conn=${aiPc.connectionState},ice=${aiPc.iceConnectionState},signaling=${aiPc.signalingState},remote=${aiPc.remoteDescription?.type || 'none'}`;
    }

    function aiReady() {
        return Boolean(aiPc?.remoteDescription && (
            aiPc.connectionState === 'connected'
            || aiPc.iceConnectionState === 'connected'
            || aiPc.iceConnectionState === 'completed'
        ));
    }

    function waitForAiReady(timeoutMs = 10000) {
        if (aiReady()) return Promise.resolve(true);
        return new Promise((resolve) => {
            const startedAt = Date.now();
            const timer = setInterval(() => {
                if (aiReady()) {
                    clearInterval(timer);
                    resolve(true);
                } else if (Date.now() - startedAt >= timeoutMs) {
                    clearInterval(timer);
                    resolve(false);
                }
            }, 250);
        });
    }

    function checkAiInput(track) {
        if (inputHealthTimer) clearTimeout(inputHealthTimer);
        inputHealthTimer = setTimeout(async () => {
            if (!aiAudioSender || aiAudioSender.track !== track) return;
            await waitForAiReady();
            const before = await outboundBytes(aiAudioSender);
            await new Promise((resolve) => setTimeout(resolve, 2500));
            const after = await outboundBytes(aiAudioSender);
            log(`AI input packet check: before=${before}, after=${after}, ${aiState()}`, true);
        }, 500);
    }

    function checkAiOutput(track) {
        if (outputHealthTimer) clearTimeout(outputHealthTimer);
        outputHealthTimer = setTimeout(async () => {
            if (!selectedBusinessSender || selectedBusinessSender.track !== track) return;
            const before = await outboundBytes(selectedBusinessSender);
            await new Promise((resolve) => setTimeout(resolve, 2500));
            const after = await outboundBytes(selectedBusinessSender);
            log(`AI output packet check: before=${before}, after=${after}, sender=${trackLabel(selectedBusinessSender.track)}`, true);
        }, 800);
    }

    async function attachAudioToAi() {
        if (!shouldSendAudioToAi()) return false;
        if (!aiAudioSender || !isLive(selectedRemoteAudio)) return false;
        if (aiAudioSender.track === selectedRemoteAudio) return true;
        await aiAudioSender.replaceTrack(selectedRemoteAudio);
        log(`AI input uses ${trackLabel(selectedRemoteAudio)} from ${STATIC_AUDIO_ELEMENT_REASON}`, true);
        checkAiInput(selectedRemoteAudio);
        return true;
    }

    async function attachVideoToAi() {
        if (!shouldSendVideoToAi()) return false;
        if (!aiVideoSender || !isLive(selectedRemoteVideo)) return false;
        if (aiVideoSender.track === selectedRemoteVideo) return true;
        await aiVideoSender.replaceTrack(selectedRemoteVideo);
        log(`AI video uses ${trackLabel(selectedRemoteVideo)} from ${STATIC_VIDEO_ELEMENT_REASON}`, true);
        return true;
    }

    async function attachAiOutputToBusiness() {
        selectBusinessSender('before-output');
        if (!isAiTakeover || !selectedBusinessSender || !isLive(aiAudioTrack)) {
            log(`AI output waiting: takeover=${isAiTakeover}, sender=${Boolean(selectedBusinessSender)}, aiTrack=${trackLabel(aiAudioTrack)}`);
            return false;
        }
        if (selectedBusinessSender.track === aiAudioTrack) return true;
        await selectedBusinessSender.replaceTrack(aiAudioTrack);
        aiAttached = true;
        log(`business sender uses AI audio ${trackLabel(aiAudioTrack)}`, true);
        checkAiOutput(aiAudioTrack);
        return true;
    }

    async function restoreBusinessAudio() {
        if (!selectedBusinessSender || !aiAttached) return;
        await selectedBusinessSender.replaceTrack(originalBusinessTrack || null);
        aiAttached = false;
        log(`business sender restored ${trackLabel(originalBusinessTrack)}`, true);
    }

    function wrapTrackListener(listener) {
        if (!listener || listener.__aiNativeElementWrapped) return listener;
        const wrapped = function (event) {
            const ownerPc = this instanceof RTCPeerConnection ? this : event?.currentTarget;
            if (!isInternalPc(ownerPc) && event?.track) {
                rememberRemoteReceiver(event.receiver, 'pc-track');
                for (const stream of event.streams || []) rememberRemoteStream(stream, 'pc-track-stream');
            }
            if (typeof listener === 'function') return listener.apply(this, arguments);
            if (listener?.handleEvent) return listener.handleEvent(event);
            return undefined;
        };
        wrapped.__aiNativeElementWrapped = true;
        return wrapped;
    }

    RTCPeerConnection.prototype.addEventListener = function (type, listener, options) {
        if (type === 'track') return originalAddEventListener.call(this, type, wrapTrackListener(listener), options);
        return originalAddEventListener.call(this, type, listener, options);
    };

    try {
        const descriptor = Object.getOwnPropertyDescriptor(RTCPeerConnection.prototype, 'ontrack');
        Object.defineProperty(RTCPeerConnection.prototype, 'ontrack', {
            configurable: true,
            enumerable: true,
            get() {
                return descriptor?.get ? descriptor.get.call(this) : this.__aiNativeElementOnTrack || null;
            },
            set(listener) {
                const wrapped = wrapTrackListener(listener);
                this.__aiNativeElementOnTrack = wrapped;
                if (descriptor?.set) descriptor.set.call(this, wrapped);
                else this.addEventListener('track', wrapped);
            },
        });
    } catch (error) {
        console.warn('[AI Native Element] failed to wrap ontrack', error);
    }

    RTCPeerConnection.prototype.addTrack = function (track, ...streams) {
        const sender = originalAddTrack.call(this, track, ...streams);
        if (!isInternalPc(this) && track?.kind === 'audio') rememberBusinessSender(sender, track, 'pc-addTrack');
        return sender;
    };

    if (originalAddTransceiver) {
        RTCPeerConnection.prototype.addTransceiver = function (trackOrKind, init) {
            const transceiver = originalAddTransceiver.call(this, trackOrKind, init);
            if (!isInternalPc(this)) {
                const kind = trackOrKind instanceof MediaStreamTrack ? trackOrKind.kind : trackOrKind;
                if (kind === 'audio') {
                    const track = trackOrKind instanceof MediaStreamTrack ? trackOrKind : transceiver.sender?.track;
                    rememberBusinessSender(transceiver.sender, track, 'pc-addTransceiver');
                }
            }
            return transceiver;
        };
    }

    RTCPeerConnection.prototype.setRemoteDescription = function () {
        const result = originalSetRemoteDescription.apply(this, arguments);
        if (!isInternalPc(this)) {
            Promise.resolve(result).then(() => {
                for (const receiver of this.getReceivers?.() || []) rememberRemoteReceiver(receiver, 'receiver-after-srd');
                for (const sender of this.getSenders?.() || []) rememberBusinessSender(sender, sender.track, 'sender-after-srd');
            }).catch(() => {});
        }
        return result;
    };

    if (mediaSrcObjectDescriptor?.set) {
        Object.defineProperty(HTMLMediaElement.prototype, 'srcObject', {
            configurable: true,
            enumerable: mediaSrcObjectDescriptor.enumerable,
            get() {
                return mediaSrcObjectDescriptor.get.call(this);
            },
            set(stream) {
                if (!this.__aiNativeElementCopilotElement) {
                    const reason = elementReasonFor(this) || `${this.tagName.toLowerCase()}-srcObject`;
                    rememberRemoteStream(stream, reason);
                }
                return mediaSrcObjectDescriptor.set.call(this, stream);
            },
        });
    }

    function scanMediaElements() {
        document.querySelectorAll('audio').forEach((element, index) => {
            if (element.__aiNativeElementCopilotElement) return;
            rememberRemoteStream(element.srcObject, `element-${index}:audio`);
        });
        document.querySelectorAll('video').forEach((element, index) => {
            if (element.__aiNativeElementCopilotElement) return;
            rememberRemoteStream(element.srcObject, `element-${index}:video`);
        });
        selectRemoteAudio('media-scan');
        selectRemoteVideo('media-scan');
    }

    setInterval(scanMediaElements, 1000);

    async function connectAi(signalingUrl, assistantId) {
        disconnectAi();

        const id = pcId();
        aiPc = new RTCPeerConnection({ iceServers: [{ urls: 'stun:stun.l.google.com:19302' }] });
        markInternalPc(aiPc);
        aiPc.onconnectionstatechange = () => log(`AI PC connectionState=${aiPc.connectionState}`);
        aiPc.oniceconnectionstatechange = () => log(`AI PC iceConnectionState=${aiPc.iceConnectionState}`);

        aiDc = aiPc.createDataChannel('chat');
        aiDc.onopen = () => {
            setStatus('connected');
            log('AI data channel open', true);
            aiDc.send(JSON.stringify({ type: 'client-ready' }));
        };
        aiDc.onclose = () => setStatus('disconnected');
        aiDc.onmessage = (event) => {
            try {
                const msg = JSON.parse(event.data);
                const content = msg.delta || msg.content;
                if (msg.type === 'transcript') {
                    logUserTranscript(content);
                } else if (msg.type === 'assistant-text-start') {
                    startAssistantLine();
                } else if (msg.type === 'assistant-text-delta') {
                    appendAssistantDelta(content);
                } else if (msg.type === 'assistant-text-end') {
                    finishAssistantLine();
                } else {
                    log(`data channel message: ${msg.type}`);
                }
            } catch {
                appendChatLine('DATA', event.data);
            }
        };

        scanMediaElements();
        selectRemoteAudio('connect');
        selectRemoteVideo('connect');
        selectBusinessSender('connect');

        const sendAudio = shouldSendAudioToAi();
        const audioTransceiver = sendAudio && isLive(selectedRemoteAudio)
            ? aiPc.addTransceiver(selectedRemoteAudio, { direction: 'sendrecv' })
            : aiPc.addTransceiver('audio', { direction: sendAudio ? 'sendrecv' : 'recvonly' });
        aiAudioSender = audioTransceiver.sender;
        log(!sendAudio
            ? 'AI audio uplink disabled by panel setting'
            : isLive(selectedRemoteAudio)
            ? `AI input starts with ${trackLabel(selectedRemoteAudio)} (${STATIC_AUDIO_ELEMENT_REASON})`
            : `AI input waiting for ${STATIC_AUDIO_ELEMENT_REASON}`, true);

        const sendVideo = shouldSendVideoToAi();
        const shouldSendVideo = sendVideo && isLive(selectedRemoteVideo) && !selectedRemoteVideo.muted;
        if (shouldSendVideo) {
            const videoTransceiver = aiPc.addTransceiver(selectedRemoteVideo, { direction: 'sendonly' });
            aiVideoSender = videoTransceiver.sender;
            log(`AI video starts with ${trackLabel(selectedRemoteVideo)} (${STATIC_VIDEO_ELEMENT_REASON})`);
        } else {
            aiVideoSender = null;
            log(sendVideo
                ? `AI video disabled: waiting for live track at ${STATIC_VIDEO_ELEMENT_REASON}`
                : 'AI video uplink disabled by panel setting');
        }

        aiPc.ontrack = (event) => {
            if (event.track.kind !== 'audio') return;
            aiOutputTrackIds.add(event.track.id);
            remoteAudio.delete(event.track.id);
            aiAudioTrack = event.track;
            log(`received AI audio ${trackLabel(aiAudioTrack)}`, true);
            aiAudioTrack.onunmute = () => {
                log(`AI audio unmuted ${trackLabel(aiAudioTrack)}`);
                attachAiOutputToBusiness();
            };
            attachAiOutputToBusiness();
        };

        aiPc.onicecandidate = (event) => {
            if (aiWs?.readyState !== WebSocket.OPEN) return;
            aiWs.send(JSON.stringify({
                type: 'ice-candidate',
                payload: {
                    pc_id: id,
                    candidate: event.candidate ? {
                        candidate: event.candidate.candidate,
                        sdpMid: event.candidate.sdpMid,
                        sdpMLineIndex: event.candidate.sdpMLineIndex,
                    } : null,
                },
            }));
        };

        setStatus('connecting');
        aiWs = new WebSocket(signalingUrl);
        aiWs.onopen = async () => {
            const offer = await aiPc.createOffer();
            await aiPc.setLocalDescription(offer);
            aiWs.send(JSON.stringify({
                type: 'offer',
                payload: {
                    pc_id: id,
                    sdp: aiPc.localDescription.sdp,
                    type: aiPc.localDescription.type,
                    assistant_id: assistantId,
                    vision_enabled: shouldSendVideo,
                },
            }));
            log('sent AI WebRTC offer', true);
        };
        aiWs.onmessage = async (event) => {
            try {
                const msg = JSON.parse(event.data);
                if (msg.type === 'answer') {
                    await aiPc.setRemoteDescription({ type: 'answer', sdp: msg.payload.sdp });
                    log(`AI WebRTC answer applied; ${aiState()}`, true);
                } else if (msg.type === 'ice-candidate' && msg.payload?.candidate) {
                    await aiPc.addIceCandidate(msg.payload.candidate).catch(() => {});
                } else if (msg.type === 'error') {
                    throw new Error(msg.payload?.message || 'server error');
                }
            } catch (error) {
                log(`signaling error: ${error.message || error}`);
            }
        };
        aiWs.onerror = () => {
            setStatus('failed');
            log('AI signaling websocket error');
        };
        aiWs.onclose = () => setStatus('disconnected');

        attachAudioToAi();
        attachVideoToAi();
    }

    function disconnectAi() {
        try { aiDc?.close(); } catch {}
        try { aiPc?.close(); } catch {}
        try { aiWs?.close(); } catch {}
        aiDc = null;
        aiPc = null;
        aiWs = null;
        aiAudioSender = null;
        aiVideoSender = null;
        aiAudioTrack = null;
        if (inputRecorder?.state === 'recording') stopInputRecording();
        setStatus('disconnected');
    }

    function setStatus(status) {
        const el = document.getElementById('element-copilot-status');
        if (!el) return;
        el.textContent = {
            disconnected: '未连接',
            connecting: '连接中',
            connected: '已连接',
            failed: '连接失败',
        }[status] || status;
    }

    function updateModeButton() {
        const button = document.getElementById('element-copilot-toggle');
        if (!button) return;
        if (isAiTakeover) {
            button.textContent = '当前：AI 接管｜点击切回人工';
            button.style.background = '#8b5cf6';
        } else {
            button.textContent = '当前：人工接管｜点击切换 AI';
            button.style.background = '#10b981';
        }
    }

    window.__aiNativeElementDump = function () {
        return {
            staticAudioElement: STATIC_AUDIO_ELEMENT_REASON,
            staticVideoElement: STATIC_VIDEO_ELEMENT_REASON,
            selectedInput: trackLabel(selectedRemoteAudio),
            selectedVideo: trackLabel(selectedRemoteVideo),
            aiVideoSenderTrack: trackLabel(aiVideoSender?.track),
            selectedOutput: trackLabel(selectedBusinessSender?.track),
            originalOutput: trackLabel(originalBusinessTrack),
            aiAudio: trackLabel(aiAudioTrack),
            aiAttached,
            aiState: aiState(),
            recording: inputRecorder?.state === 'recording' ? {
                track: trackLabel(inputRecordingTrack),
                seconds: ((Date.now() - inputRecordingStartedAt) / 1000).toFixed(1),
                chunks: inputRecordingChunks.length,
            } : null,
            inputs: Array.from(remoteAudio.values()).map((item) => ({
                selected: item.track === selectedRemoteAudio,
                id: item.track.id,
                muted: item.track.muted,
                live: item.track.readyState,
                hasReceiver: Boolean(item.receiver),
                matchesStaticElement: hasElementReason(item, STATIC_AUDIO_ELEMENT_REASON),
                bytesReceived: item.bytesReceived || 0,
                packetsReceived: item.packetsReceived || 0,
                bytesDelta: item.bytesDelta,
                packetsDelta: item.packetsDelta,
                reasons: Array.from(item.reasons),
            })),
            videos: Array.from(remoteVideo.values()).map((item) => ({
                selected: item.track === selectedRemoteVideo,
                id: item.track.id,
                muted: item.track.muted,
                live: item.track.readyState,
                hasReceiver: Boolean(item.receiver),
                matchesStaticElement: hasElementReason(item, STATIC_VIDEO_ELEMENT_REASON),
                reasons: Array.from(item.reasons),
            })),
            outputs: Array.from(businessSenders.values()).map((item) => ({
                selected: item.sender === selectedBusinessSender,
                id: item.id,
                track: trackLabel(item.sender.track || item.track),
                originalTrack: trackLabel(item.originalTrack),
                pcAddTrack: item.sources.has('pc-addTrack'),
                isRemoteInput: isRemoteInputTrack(item.sender.track || item.track),
                bytesSent: item.bytesSent,
                packetsSent: item.packetsSent,
                bytesDelta: item.bytesDelta,
                packetsDelta: item.packetsDelta,
                sources: Array.from(item.sources),
            })),
        };
    };

    function renderPanel() {
        if (!document.body || document.getElementById('element-copilot-panel')) return;
        const panel = document.createElement('div');
        panel.id = 'element-copilot-panel';
        panel.style.cssText = [
            'position:fixed',
            'top:20px',
            'left:20px',
            'width:360px',
            'z-index:999999',
            'box-sizing:border-box',
            'padding:16px',
            'border-radius:10px',
            'background:rgba(17,24,39,.96)',
            'color:white',
            'font-family:system-ui,-apple-system,BlinkMacSystemFont,sans-serif',
            'box-shadow:0 12px 32px rgba(0,0,0,.35)',
        ].join(';');
        panel.innerHTML = `
            <div style="display:flex;justify-content:space-between;gap:12px;align-items:center;margin-bottom:12px;">
                <strong style="font-size:15px;color:#f9a8d4;">AI 元素选轨</strong>
                <span id="element-copilot-status" style="font-size:12px;color:#d1d5db;">未连接</span>
            </div>
            <div style="font-size:11px;color:#9ca3af;margin-bottom:10px;line-height:1.5;">
                音频输入：${STATIC_AUDIO_ELEMENT_REASON}<br>
                视频输入：${STATIC_VIDEO_ELEMENT_REASON}
            </div>
            <label style="display:block;font-size:12px;color:#9ca3af;margin-bottom:4px;">信令地址</label>
            <input id="element-copilot-url" value="${DEFAULT_SIGNALING_URL}" style="width:100%;box-sizing:border-box;margin-bottom:10px;padding:8px;border:1px solid #4b5563;border-radius:6px;background:#111827;color:white;">
            <label style="display:block;font-size:12px;color:#9ca3af;margin-bottom:4px;">助手 ID</label>
            <input id="element-copilot-assistant" placeholder="请输入助手 ID" style="width:100%;box-sizing:border-box;margin-bottom:12px;padding:8px;border:1px solid #4b5563;border-radius:6px;background:#111827;color:white;">
            <div style="display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-bottom:12px;">
                <label style="display:flex;align-items:center;gap:6px;padding:8px;border:1px solid #374151;border-radius:6px;background:#111827;font-size:12px;color:#e5e7eb;cursor:pointer;">
                    <input id="element-copilot-send-audio" type="checkbox" style="margin:0;">
                    <span>传音频给 AI</span>
                </label>
                <label style="display:flex;align-items:center;gap:6px;padding:8px;border:1px solid #374151;border-radius:6px;background:#111827;font-size:12px;color:#e5e7eb;cursor:pointer;">
                    <input id="element-copilot-send-video" type="checkbox" style="margin:0;">
                    <span>传视频给 AI</span>
                </label>
            </div>
            <div style="margin-bottom:10px;">
                <div style="display:flex;justify-content:space-between;font-size:12px;color:#d1fae5;margin-bottom:4px;"><span>${STATIC_AUDIO_ELEMENT_REASON}</span><span>原生音轨</span></div>
                <div style="height:8px;border-radius:999px;overflow:hidden;background:#374151;"><div id="element-copilot-input-vu" style="height:100%;width:0%;background:linear-gradient(90deg,#10b981,#fcd34d);transition:width .06s linear;"></div></div>
            </div>
            <div style="margin-bottom:12px;">
                <div style="display:flex;justify-content:space-between;font-size:12px;color:#bfdbfe;margin-bottom:4px;"><span>AI 输出</span><span>业务上行</span></div>
                <div style="height:8px;border-radius:999px;overflow:hidden;background:#374151;"><div id="element-copilot-output-vu" style="height:100%;width:0%;background:linear-gradient(90deg,#60a5fa,#c084fc);transition:width .06s linear;"></div></div>
            </div>
            <button id="element-copilot-toggle" style="width:100%;padding:12px;border:0;border-radius:6px;background:#10b981;color:white;font-weight:700;cursor:pointer;">当前：人工接管｜点击切换 AI</button>
            <button id="element-copilot-record" style="width:100%;margin-top:8px;padding:10px;border:0;border-radius:6px;background:#2563eb;color:white;font-weight:700;cursor:pointer;">录制 AI 输入</button>
            <div id="element-copilot-log" style="height:170px;margin-top:12px;padding:8px;overflow:auto;border:1px solid #374151;border-radius:6px;background:#030712;color:#a7f3d0;font:11px ui-monospace,Menlo,monospace;">
                <span data-placeholder="1" style="color:#6b7280;">等待交互...</span>
            </div>
        `;
        document.body.appendChild(panel);

        const toggle = document.getElementById('element-copilot-toggle');
        const recordButton = document.getElementById('element-copilot-record');
        const urlInput = document.getElementById('element-copilot-url');
        const assistantInput = document.getElementById('element-copilot-assistant');
        const sendAudioInput = document.getElementById('element-copilot-send-audio');
        const sendVideoInput = document.getElementById('element-copilot-send-video');
        sendAudioInput.checked = shouldSendAudioToAi();
        sendVideoInput.checked = shouldSendVideoToAi();
        sendAudioInput.addEventListener('change', () => {
            writeBoolSetting(AUDIO_UPLINK_STORAGE_KEY, sendAudioInput.checked);
            log(`AI audio uplink setting: ${sendAudioInput.checked ? 'on' : 'off'}`);
        });
        sendVideoInput.addEventListener('change', () => {
            writeBoolSetting(VIDEO_UPLINK_STORAGE_KEY, sendVideoInput.checked);
            log(`AI video uplink setting: ${sendVideoInput.checked ? 'on' : 'off'}`);
        });
        recordButton.addEventListener('click', toggleInputRecording);
        toggle.addEventListener('click', async () => {
            if (!isAiTakeover && !assistantInput.value.trim()) {
                alert('请先填写助手 ID。');
                return;
            }
            isAiTakeover = !isAiTakeover;
            updateModeButton();
            if (isAiTakeover) {
                await connectAi(urlInput.value.trim(), assistantInput.value.trim());
                await attachAiOutputToBusiness();
            } else {
                await restoreBusinessAudio();
                disconnectAi();
            }
        });
        updateModeButton();
        updateRecordButton();
    }

    function renderPanelSoon() {
        try { renderPanel(); } catch (error) { console.warn('[AI Native Element] panel error', error); }
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', renderPanelSoon, { once: true });
    } else {
        renderPanelSoon();
    }
    requestAnimationFrame(renderVu);
    setInterval(refreshStats, 250);
    setTimeout(renderPanelSoon, 1500);
    setTimeout(renderPanelSoon, 3000);
    window.addEventListener('beforeunload', () => {
        if (inputRecorder?.state === 'recording') stopInputRecording();
    });
})();