
import React, { useState, useEffect, useRef } from 'react';
import { Plus, Search, Play, Copy, Trash2, Edit2, Mic, MessageSquare, Save, Video, PhoneOff, Camera, ArrowLeftRight, Send, Phone, MoreHorizontal, Rocket, AlertTriangle } from 'lucide-react';
import { Button, Input, Card, Badge, Drawer, Dialog } from '../components/UI';
import { mockAssistants, mockKnowledgeBases } from '../services/mockData';
import { Assistant, TabValue } from '../types';
import { GoogleGenAI } from "@google/genai";

export const AssistantsPage: React.FC = () => {
  const [assistants, setAssistants] = useState<Assistant[]>(mockAssistants);
  const [searchTerm, setSearchTerm] = useState('');
  const [selectedId, setSelectedId] = useState<string | null>(null);
  const [activeTab, setActiveTab] = useState<TabValue>(TabValue.GLOBAL);
  const [debugOpen, setDebugOpen] = useState(false);
  const [hotwordInput, setHotwordInput] = useState('');
  
  // State for delete confirmation dialog
  const [deleteId, setDeleteId] = useState<string | null>(null);

  const selectedAssistant = assistants.find(a => a.id === selectedId) || null;

  const filteredAssistants = assistants.filter(a => 
    a.name.toLowerCase().includes(searchTerm.toLowerCase())
  );

  const handleCreate = () => {
    const newId = Date.now().toString();
    const newAssistant: Assistant = {
      id: newId,
      name: 'New Assistant',
      callCount: 0,
      opener: '',
      prompt: '',
      knowledgeBaseId: '',
      language: 'zh',
      voice: 'default',
      speed: 1,
      hotwords: []
    };
    setAssistants([...assistants, newAssistant]);
    setSelectedId(newId);
  };

  const handleCopy = (e: React.MouseEvent, assistant: Assistant) => {
    e.stopPropagation();
    const newAssistant = { ...assistant, id: Date.now().toString(), name: `${assistant.name} (Copy)` };
    setAssistants([...assistants, newAssistant]);
  };

  const handleDeleteClick = (e: React.MouseEvent, id: string) => {
    e.stopPropagation();
    setDeleteId(id);
  };

  const confirmDelete = () => {
    if (deleteId) {
        setAssistants(prev => prev.filter(a => a.id !== deleteId));
        if (selectedId === deleteId) setSelectedId(null);
        setDeleteId(null);
    }
  };

  const updateAssistant = (field: keyof Assistant, value: any) => {
    if (!selectedId) return;
    setAssistants(prev => prev.map(a => a.id === selectedId ? { ...a, [field]: value } : a));
  };

  const addHotword = () => {
    if (hotwordInput.trim() && selectedAssistant) {
      updateAssistant('hotwords', [...selectedAssistant.hotwords, hotwordInput.trim()]);
      setHotwordInput('');
    }
  };

  const removeHotword = (word: string) => {
    if (selectedAssistant) {
      updateAssistant('hotwords', selectedAssistant.hotwords.filter(w => w !== word));
    }
  };

  return (
    <div className="flex h-[calc(100vh-6rem)] gap-6 animate-in fade-in">
      {/* LEFT COLUMN: List */}
      <div className="w-80 flex flex-col gap-4 shrink-0">
        <div className="flex items-center justify-between px-1">
            <h2 className="text-xl font-bold tracking-tight">小助手列表</h2>
        </div>
        
        <div className="flex gap-2">
            <div className="relative flex-1">
                <Search className="absolute left-2.5 top-2.5 h-4 w-4 text-muted-foreground" />
                <Input 
                  placeholder="搜索..." 
                  className="pl-9 bg-card/50 border-white/5"
                  value={searchTerm}
                  onChange={(e) => setSearchTerm(e.target.value)}
                />
            </div>
            <Button size="icon" onClick={handleCreate} title="新建小助手">
                <Plus className="h-5 w-5" />
            </Button>
        </div>

        <div className="flex-1 overflow-y-auto space-y-2 pr-1 custom-scrollbar">
            {filteredAssistants.map(assistant => (
                <div 
                    key={assistant.id}
                    onClick={() => setSelectedId(assistant.id)}
                    className={`group relative flex flex-col p-4 rounded-xl border transition-all cursor-pointer ${
                        selectedId === assistant.id 
                        ? 'bg-primary/10 border-primary/40 shadow-[0_0_15px_rgba(6,182,212,0.15)]' 
                        : 'bg-card/30 border-white/5 hover:bg-white/5 hover:border-white/10'
                    }`}
                >
                    <div className="flex justify-between items-start mb-2">
                        <span className={`font-semibold truncate pr-6 ${selectedId === assistant.id ? 'text-primary' : 'text-foreground'}`}>
                            {assistant.name}
                        </span>
                    </div>
                    
                    <div className="flex items-center text-xs text-muted-foreground">
                        <Phone className="h-3 w-3 mr-1.5 opacity-70" />
                        <span>{assistant.callCount} 次通话</span>
                    </div>

                    {/* Hover Actions */}
                    <div className="absolute right-2 top-2 flex space-x-1 opacity-0 group-hover:opacity-100 transition-opacity bg-background/50 backdrop-blur-sm rounded-lg p-0.5">
                        <Button variant="ghost" size="icon" className="h-7 w-7" onClick={(e) => handleCopy(e, assistant)} title="复制">
                            <Copy className="h-3.5 w-3.5" />
                        </Button>
                        <Button variant="ghost" size="icon" className="h-7 w-7 text-destructive hover:text-destructive" onClick={(e) => handleDeleteClick(e, assistant.id)} title="删除">
                            <Trash2 className="h-3.5 w-3.5" />
                        </Button>
                    </div>
                </div>
            ))}
            {filteredAssistants.length === 0 && (
                <div className="text-center py-10 text-muted-foreground text-sm">
                    未找到小助手
                </div>
            )}
        </div>
      </div>

      {/* RIGHT COLUMN: Config Panel */}
      <div className="flex-1 bg-card/20 backdrop-blur-sm border border-white/5 rounded-2xl overflow-hidden flex flex-col relative shadow-xl">
        {selectedAssistant ? (
            <>
                {/* Header Area */}
                <div className="p-6 border-b border-white/5 bg-white/[0.02] space-y-4">
                    {/* Row 1: Name and Actions - Aligned with items-end */}
                    <div className="flex items-end justify-between gap-4">
                        <div className="flex-1">
                            <label className="text-xs text-muted-foreground font-mono mb-2 block ml-1">ASSISTANT NAME</label>
                            <Input 
                                value={selectedAssistant.name}
                                onChange={(e) => updateAssistant('name', e.target.value)}
                                className="font-bold bg-white/5 border-white/10 focus:border-primary/50 text-base"
                            />
                        </div>
                        <div className="flex items-center space-x-2">
                             <Button 
                                variant="secondary" 
                                onClick={() => setDebugOpen(true)} 
                                className="border border-primary/20 hover:border-primary/50 text-primary hover:text-primary hover:bg-primary/10 shadow-[0_0_15px_rgba(6,182,212,0.1)]"
                             >
                                <Play className="mr-2 h-4 w-4" /> 调试
                            </Button>
                            <Button 
                                onClick={() => alert("发布成功！")} 
                                className="shadow-[0_0_20px_rgba(6,182,212,0.3)]"
                            >
                                <Rocket className="mr-2 h-4 w-4" /> 发布
                            </Button>
                        </div>
                    </div>

                    {/* Row 2: Tabs */}
                    <div className="flex bg-white/5 p-1 rounded-lg w-fit">
                        <button
                            onClick={() => setActiveTab(TabValue.GLOBAL)}
                            className={`px-6 py-1.5 text-sm font-medium rounded-md transition-all ${activeTab === TabValue.GLOBAL ? 'bg-primary text-primary-foreground shadow-sm' : 'text-muted-foreground hover:text-foreground hover:bg-white/5'}`}
                        >
                            全局配置
                        </button>
                        <button
                            onClick={() => setActiveTab(TabValue.VOICE)}
                            className={`px-6 py-1.5 text-sm font-medium rounded-md transition-all ${activeTab === TabValue.VOICE ? 'bg-primary text-primary-foreground shadow-sm' : 'text-muted-foreground hover:text-foreground hover:bg-white/5'}`}
                        >
                            语音配置
                        </button>
                    </div>
                </div>

                {/* Content Scroll Area */}
                <div className="flex-1 overflow-y-auto p-8 custom-scrollbar">
                    <div className="max-w-4xl mx-auto space-y-8 animate-in slide-in-from-bottom-2 duration-300">
                        {activeTab === TabValue.GLOBAL ? (
                            <div className="space-y-6">
                                <div className="space-y-2">
                                    <label className="text-sm font-medium text-foreground flex items-center">
                                        <MessageSquare className="w-4 h-4 mr-2 text-primary"/> 开场白 (Opener)
                                    </label>
                                    <Input 
                                        value={selectedAssistant.opener}
                                        onChange={(e) => updateAssistant('opener', e.target.value)}
                                        placeholder="例如：您好，我是您的专属AI助手..."
                                        className="bg-white/5 border-white/10 focus:border-primary/50"
                                    />
                                    <p className="text-xs text-muted-foreground">接通通话后的第一句话。</p>
                                </div>

                                <div className="space-y-2">
                                    <label className="text-sm font-medium text-foreground flex items-center">
                                        <BotIcon className="w-4 h-4 mr-2 text-primary"/> 提示词 (Prompt)
                                    </label>
                                    <textarea 
                                        className="flex min-h-[200px] w-full rounded-xl border border-white/10 bg-white/5 px-4 py-3 text-sm shadow-sm placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary/50 resize-y"
                                        value={selectedAssistant.prompt}
                                        onChange={(e) => updateAssistant('prompt', e.target.value)}
                                        placeholder="设定小助手的人设、语气、行为规范以及业务逻辑..."
                                    />
                                </div>

                                <div className="space-y-2">
                                    <label className="text-sm font-medium text-foreground">知识库绑定</label>
                                    <select 
                                        className="flex h-10 w-full rounded-md border border-white/10 bg-white/5 px-3 py-1 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary/50 [&>option]:bg-card text-foreground"
                                        value={selectedAssistant.knowledgeBaseId}
                                        onChange={(e) => updateAssistant('knowledgeBaseId', e.target.value)}
                                    >
                                        <option value="">如果不选择，则使用通用大模型知识</option>
                                        {mockKnowledgeBases.map(kb => (
                                            <option key={kb.id} value={kb.id}>{kb.name}</option>
                                        ))}
                                    </select>
                                </div>
                            </div>
                        ) : (
                            <div className="space-y-8">
                                <div className="grid grid-cols-2 gap-6">
                                    <div className="space-y-2">
                                        <label className="text-sm font-medium text-foreground">语言 (Language)</label>
                                        <select 
                                            className="flex h-10 w-full rounded-md border border-white/10 bg-white/5 px-3 py-1 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary/50 [&>option]:bg-card text-foreground"
                                            value={selectedAssistant.language}
                                            onChange={(e) => updateAssistant('language', e.target.value)}
                                        >
                                            <option value="zh">中文 (Chinese)</option>
                                            <option value="en">英文 (English)</option>
                                        </select>
                                    </div>
                                    <div className="space-y-2">
                                        <label className="text-sm font-medium text-foreground">音色 (Voice)</label>
                                        <select 
                                            className="flex h-10 w-full rounded-md border border-white/10 bg-white/5 px-3 py-1 text-sm shadow-sm transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-primary/50 [&>option]:bg-card text-foreground"
                                            value={selectedAssistant.voice}
                                            onChange={(e) => updateAssistant('voice', e.target.value)}
                                        >
                                            <option value="default">默认 (Default)</option>
                                            <option value="alloy">Alloy</option>
                                            <option value="echo">Echo</option>
                                            <option value="fable">Fable</option>
                                            <option value="onyx">Onyx</option>
                                            <option value="nova">Nova</option>
                                            <option value="shimmer">Shimmer</option>
                                        </select>
                                    </div>
                                </div>

                                <div className="space-y-4 p-4 rounded-xl border border-white/5 bg-white/[0.02]">
                                    <div className="flex justify-between items-center">
                                        <label className="text-sm font-medium text-foreground">语速 (Speed)</label>
                                        <span className="text-sm font-mono text-primary bg-primary/10 px-2 py-0.5 rounded">{selectedAssistant.speed}x</span>
                                    </div>
                                    <input 
                                        type="range" 
                                        min="0.5" 
                                        max="2.0" 
                                        step="0.1" 
                                        value={selectedAssistant.speed}
                                        onChange={(e) => updateAssistant('speed', parseFloat(e.target.value))}
                                        className="w-full h-2 bg-secondary rounded-lg appearance-none cursor-pointer accent-primary"
                                    />
                                    <div className="flex justify-between text-xs text-muted-foreground">
                                        <span>0.5x (Slow)</span>
                                        <span>1.0x (Normal)</span>
                                        <span>2.0x (Fast)</span>
                                    </div>
                                </div>

                                <div className="space-y-3">
                                    <label className="text-sm font-medium text-foreground flex items-center">
                                        <Mic className="w-4 h-4 mr-2 text-primary"/> ASR 热词优化 (Hotwords)
                                    </label>
                                    <div className="flex space-x-2">
                                        <Input 
                                            value={hotwordInput}
                                            onChange={(e) => setHotwordInput(e.target.value)}
                                            placeholder="输入专有名词或高频词汇..."
                                            onKeyDown={(e) => e.key === 'Enter' && addHotword()}
                                            className="bg-white/5 border-white/10"
                                        />
                                        <Button variant="secondary" onClick={addHotword}>添加</Button>
                                    </div>
                                    <div className="flex flex-wrap gap-2 min-h-[40px] p-2 rounded-lg border border-dashed border-white/10">
                                        {selectedAssistant.hotwords.length === 0 && (
                                            <span className="text-xs text-muted-foreground py-1">暂无热词</span>
                                        )}
                                        {selectedAssistant.hotwords.map((word, idx) => (
                                            <Badge key={idx} variant="outline">
                                                {word}
                                                <button onClick={() => removeHotword(word)} className="ml-2 hover:text-destructive transition-colors">×</button>
                                            </Badge>
                                        ))}
                                    </div>
                                    <p className="text-xs text-muted-foreground">添加热词可以提高语音识别特定词汇的准确率。</p>
                                </div>
                            </div>
                        )}
                    </div>
                </div>
            </>
        ) : (
            <div className="flex-1 flex flex-col items-center justify-center text-muted-foreground">
                <div className="w-16 h-16 rounded-2xl bg-white/5 flex items-center justify-center mb-4">
                    <BotIcon className="h-8 w-8 opacity-50" />
                </div>
                <p className="text-lg font-medium">请选择一个小助手</p>
                <p className="text-sm opacity-60">从左侧列表选择或创建一个新的小助手以开始配置</p>
            </div>
        )}
      </div>

      {selectedAssistant && (
         <DebugDrawer 
           isOpen={debugOpen} 
           onClose={() => setDebugOpen(false)} 
           assistant={selectedAssistant} 
         />
      )}

      {/* Delete Confirmation Dialog */}
      <Dialog 
        isOpen={!!deleteId} 
        onClose={() => setDeleteId(null)} 
        title="确认删除"
        footer={
            <>
                <Button variant="ghost" onClick={() => setDeleteId(null)}>取消</Button>
                <Button variant="destructive" onClick={confirmDelete}>确认删除</Button>
            </>
        }
      >
        <div className="flex items-center space-x-4">
            <div className="p-3 bg-destructive/10 rounded-full">
                <AlertTriangle className="h-6 w-6 text-destructive" />
            </div>
            <div>
                <p className="text-sm text-foreground">
                    您确定要删除此小助手吗？此操作无法撤销。
                </p>
                {deleteId && (
                    <p className="text-xs text-muted-foreground mt-1">
                        将要删除: {assistants.find(a => a.id === deleteId)?.name}
                    </p>
                )}
            </div>
        </div>
      </Dialog>
    </div>
  );
};

// Icon helper
const BotIcon = ({className}: {className?: string}) => (
    <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" className={className}>
        <path d="M12 8V4H8" />
        <rect width="16" height="12" x="4" y="8" rx="2" />
        <path d="M2 14h2" />
        <path d="M20 14h2" />
        <path d="M15 13v2" />
        <path d="M9 13v2" />
    </svg>
);

// --- Debug Drawer Component ---

const DebugDrawer: React.FC<{ isOpen: boolean; onClose: () => void; assistant: Assistant }> = ({ isOpen, onClose, assistant }) => {
  const [mode, setMode] = useState<'text' | 'voice' | 'video'>('text');
  const [messages, setMessages] = useState<{role: 'user' | 'model', text: string}[]>([]);
  const [inputText, setInputText] = useState('');
  const [isLoading, setIsLoading] = useState(false);
  
  // Media State
  const videoRef = useRef<HTMLVideoElement>(null);
  const streamRef = useRef<MediaStream | null>(null);
  const scrollRef = useRef<HTMLDivElement>(null);

  const [devices, setDevices] = useState<MediaDeviceInfo[]>([]);
  const [selectedCamera, setSelectedCamera] = useState<string>('');
  const [selectedMic, setSelectedMic] = useState<string>('');
  const [isSwapped, setIsSwapped] = useState(false); // False: AI is Big, Local is Small. True: Local is Big, AI is Small.

  // Initialize with opener
  useEffect(() => {
    if (isOpen) {
      setMessages([{ role: 'model', text: assistant.opener || "Hello!" }]);
    } else {
        // Reset and stop media when closed
        setMode('text');
        stopMedia();
        setIsSwapped(false);
    }
  }, [isOpen, assistant]);

  // Auto-scroll logic
  useEffect(() => {
      if (scrollRef.current) {
          scrollRef.current.scrollTop = scrollRef.current.scrollHeight;
      }
  }, [messages, mode]);

  // Fetch Devices
  useEffect(() => {
    if (isOpen && mode === 'video') {
        const getDevices = async () => {
            try {
                await navigator.mediaDevices.getUserMedia({ audio: true, video: true });
                const dev = await navigator.mediaDevices.enumerateDevices();
                setDevices(dev);
                
                const cams = dev.filter(d => d.kind === 'videoinput');
                const mics = dev.filter(d => d.kind === 'audioinput');
                
                if (cams.length > 0 && !selectedCamera) setSelectedCamera(cams[0].deviceId);
                if (mics.length > 0 && !selectedMic) setSelectedMic(mics[0].deviceId);

            } catch (e) {
                console.error("Error enumerating devices", e);
            }
        };
        getDevices();
    }
  }, [isOpen, mode]);

  // Handle Video/Media stream
  const stopMedia = () => {
      if (streamRef.current) {
        streamRef.current.getTracks().forEach(track => track.stop());
        streamRef.current = null;
      }
  };

  useEffect(() => {
    const handleStream = async () => {
      if (isOpen && mode === 'video') {
        try {
          stopMedia();
          const constraints = {
              video: selectedCamera ? { deviceId: { exact: selectedCamera } } : true,
              audio: selectedMic ? { deviceId: { exact: selectedMic } } : true
          };
          const stream = await navigator.mediaDevices.getUserMedia(constraints);
          streamRef.current = stream;
          if (videoRef.current) {
            videoRef.current.srcObject = stream;
          }
        } catch (err) {
          console.error("Failed to access camera/mic:", err);
        }
      } else {
        stopMedia();
      }
    };

    handleStream();
    return () => stopMedia();
  }, [mode, isOpen, selectedCamera, selectedMic]);

  const handleSend = async () => {
    if (!inputText.trim()) return;
    const userMsg = inputText;
    setMessages(prev => [...prev, { role: 'user', text: userMsg }]);
    setInputText('');
    setIsLoading(true);

    try {
      if (process.env.API_KEY) {
        const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
        const chat = ai.chats.create({
            model: "gemini-3-flash-preview",
            config: { systemInstruction: assistant.prompt },
            history: messages.map(m => ({ role: m.role, parts: [{ text: m.text }] }))
        });
        const result = await chat.sendMessage({ message: userMsg });
        setMessages(prev => [...prev, { role: 'model', text: result.text || '' }]);
      } else {
        setTimeout(() => {
            setMessages(prev => [...prev, { role: 'model', text: `[Mock Response]: Received "${userMsg}"` }]);
            setIsLoading(false);
        }, 1000);
      }
    } catch (e) {
      console.error(e);
      setMessages(prev => [...prev, { role: 'model', text: "Error: Failed to connect to AI service." }]);
    } finally {
      setIsLoading(false);
    }
  };

  const handleClose = () => {
      stopMedia();
      onClose();
  };

  // Reusable Messages List Component
  const TranscriptionLog = () => (
    <div ref={scrollRef} className="flex-1 overflow-y-auto space-y-4 p-2 border border-white/5 rounded-md bg-black/20 min-h-0">
        {messages.length === 0 && <div className="text-center text-muted-foreground text-xs py-4">暂无转写记录</div>}
        {messages.map((m, i) => (
        <div key={i} className={`flex ${m.role === 'user' ? 'justify-end' : 'justify-start'}`}>
            <div className={`max-w-[85%] rounded-lg px-3 py-2 text-sm ${m.role === 'user' ? 'bg-primary text-primary-foreground' : 'bg-card border border-white/10 shadow-sm text-foreground'}`}>
            <span className="text-[10px] opacity-70 block mb-0.5 uppercase tracking-wider">{m.role === 'user' ? 'Me' : 'AI'}</span>
            {m.text}
            </div>
        </div>
        ))}
        {isLoading && <div className="text-xs text-muted-foreground ml-2 animate-pulse">Thinking...</div>}
    </div>
  );

  // Helper to render the Local Video Element
  const renderLocalVideo = (isSmall: boolean) => (
      <div className={`relative w-full h-full bg-black overflow-hidden ${isSmall ? 'rounded-lg border border-white/20 shadow-lg' : ''}`}>
          <video 
            ref={videoRef} 
            autoPlay 
            muted 
            playsInline 
            className="w-full h-full object-cover transform scale-x-[-1]" 
          />
          <div className="absolute top-2 left-2 bg-black/50 px-2 py-0.5 rounded text-[10px] text-white/80">
              Me
          </div>
      </div>
  );

  // Helper to render the "Remote" AI Video Element (Simulated)
  const renderRemoteVideo = (isSmall: boolean) => (
      <div className={`relative w-full h-full bg-slate-900 overflow-hidden flex flex-col items-center justify-center ${isSmall ? 'rounded-lg border border-white/20 shadow-lg' : ''}`}>
           <div className="relative flex items-center justify-center">
               <div className={`rounded-full bg-primary/20 animate-pulse ${isSmall ? 'w-16 h-16' : 'w-32 h-32'}`}></div>
               <div className={`absolute rounded-full bg-primary/40 animate-ping ${isSmall ? 'w-12 h-12' : 'w-24 h-24'}`}></div>
               <div className={`absolute rounded-full bg-primary flex items-center justify-center shadow-[0_0_30px_hsl(var(--primary))] ${isSmall ? 'w-12 h-12' : 'w-24 h-24'}`}>
                   <Video className={`${isSmall ? 'w-6 h-6' : 'w-10 h-10'} text-primary-foreground`} />
               </div>
           </div>
           {!isSmall && (
             <div className="mt-4 font-mono text-primary animate-pulse text-sm">
                 {assistant.name}
             </div>
           )}
      </div>
  );

  return (
    <Drawer isOpen={isOpen} onClose={handleClose} title={`调试: ${assistant.name}`}>
      <div className="flex flex-col h-full">
        {/* Mode Toggle */}
        <div className="flex justify-center mb-4 bg-white/5 p-1 rounded-lg shrink-0">
          <button 
            className={`flex-1 py-1 text-sm rounded-md transition-all ${mode === 'text' ? 'bg-primary text-primary-foreground shadow' : 'text-muted-foreground hover:bg-white/5'}`}
            onClick={() => setMode('text')}
          >
            <MessageSquare className="inline w-4 h-4 mr-1"/> 文本
          </button>
          <button 
             className={`flex-1 py-1 text-sm rounded-md transition-all ${mode === 'voice' ? 'bg-primary text-primary-foreground shadow' : 'text-muted-foreground hover:bg-white/5'}`}
             onClick={() => setMode('voice')}
          >
            <Mic className="inline w-4 h-4 mr-1"/> 语音
          </button>
          <button 
             className={`flex-1 py-1 text-sm rounded-md transition-all ${mode === 'video' ? 'bg-primary text-primary-foreground shadow' : 'text-muted-foreground hover:bg-white/5'}`}
             onClick={() => setMode('video')}
          >
            <Video className="inline w-4 h-4 mr-1"/> 视频
          </button>
        </div>

        {/* Content Area */}
        <div className="flex-1 overflow-hidden flex flex-col min-h-0 mb-4 gap-2">
          {mode === 'text' && <TranscriptionLog />}

          {mode === 'voice' && (
            <div className="flex flex-col h-full">
                {/* Visualizer Area */}
                <div className="h-1/3 min-h-[150px] shrink-0 border border-white/5 rounded-md bg-black/20 flex flex-col items-center justify-center text-muted-foreground space-y-4 mb-2 relative overflow-hidden">
                    <div className="absolute inset-0 bg-gradient-to-b from-transparent to-black/20 pointer-events-none"></div>
                    <div className="h-24 w-24 rounded-full bg-primary/10 flex items-center justify-center animate-pulse relative z-10">
                        <Mic className="h-10 w-10 text-primary" />
                    </div>
                    <p className="text-sm relative z-10">通话中...</p>
                </div>
                {/* Transcript */}
                <h4 className="text-xs font-medium text-muted-foreground px-1">实时转写 / Live Transcription</h4>
                <TranscriptionLog />
            </div>
          )}

          {mode === 'video' && (
            <div className="flex flex-col h-full space-y-2">
                {/* Video Area (Top) */}
                <div className="h-3/5 shrink-0 flex flex-col gap-2">
                    {/* Device Settings Bar */}
                    <div className="flex gap-2 shrink-0">
                        <div className="flex-1">
                            <select 
                                className="w-full text-xs bg-white/5 border border-white/10 rounded px-2 py-1.5 focus:outline-none focus:border-primary/50 text-foreground"
                                value={selectedCamera}
                                onChange={(e) => setSelectedCamera(e.target.value)}
                            >
                                {devices.filter(d => d.kind === 'videoinput').map(d => (
                                    <option key={d.deviceId} value={d.deviceId}>{d.label || `Camera...`}</option>
                                ))}
                            </select>
                        </div>
                        <div className="flex-1">
                             <select 
                                className="w-full text-xs bg-white/5 border border-white/10 rounded px-2 py-1.5 focus:outline-none focus:border-primary/50 text-foreground"
                                value={selectedMic}
                                onChange={(e) => setSelectedMic(e.target.value)}
                             >
                                {devices.filter(d => d.kind === 'audioinput').map(d => (
                                    <option key={d.deviceId} value={d.deviceId}>{d.label || `Mic...`}</option>
                                ))}
                            </select>
                        </div>
                    </div>

                    {/* Video Container (PiP) */}
                    <div className="flex-1 relative rounded-lg overflow-hidden border border-white/10 bg-black min-h-0">
                         {/* Main Window */}
                         <div className="absolute inset-0">
                             {isSwapped ? renderLocalVideo(false) : renderRemoteVideo(false)}
                         </div>
                         {/* Small Window */}
                         <div className="absolute bottom-2 right-2 w-24 h-36 z-10 transition-all duration-300">
                             {isSwapped ? renderRemoteVideo(true) : renderLocalVideo(true)}
                         </div>
                         {/* Swap Button */}
                         <div className="absolute top-2 right-2 z-20">
                             <Button 
                                variant="secondary" 
                                size="icon" 
                                className="rounded-full h-7 w-7 bg-black/50 hover:bg-primary/80 backdrop-blur text-white border border-white/20"
                                onClick={() => setIsSwapped(!isSwapped)}
                                title="切换窗口"
                             >
                                 <ArrowLeftRight className="h-3 w-3" />
                             </Button>
                         </div>
                    </div>
                </div>

                {/* Transcript Area (Bottom) */}
                <div className="flex-1 flex flex-col min-h-0">
                     <h4 className="text-xs font-medium text-muted-foreground px-1 mb-1">实时转写 / Live Transcription</h4>
                     <TranscriptionLog />
                </div>
            </div>
          )}
        </div>

        {/* Footer Actions - Unified Input */}
        <div className="shrink-0 space-y-2">
            {(mode === 'voice' || mode === 'video') && (
                <div className="flex justify-end">
                    <Button variant="destructive" size="sm" className="w-full shadow-red-500/20 shadow-lg" onClick={handleClose}>
                        <PhoneOff className="mr-2 h-3 w-3" /> 挂断通话
                    </Button>
                </div>
            )}
            
            <div className="flex space-x-2">
                <Input 
                    value={inputText}
                    onChange={(e) => setInputText(e.target.value)}
                    placeholder={mode === 'text' ? "输入消息..." : "输入文字模拟语音/Input to simulate speech..."}
                    onKeyDown={(e) => e.key === 'Enter' && handleSend()}
                    disabled={isLoading}
                    className="flex-1"
                />
                <Button size="icon" onClick={handleSend} disabled={isLoading}>
                    <Send className="h-4 w-4" />
                </Button>
            </div>
        </div>
      </div>
    </Drawer>
  );
};
