components/ai/WorkAssistantPanel.tsx

import React, { useState, useRef, useEffect } from 'react';
import { AIChatMessage, User } from '../../types';
import { Bot, Send, Sparkles, Loader2, Image as ImageIcon, X, Trash2, Brain, ChevronDown, ChevronRight, Copy, Check, FileText, Plus, Paperclip, File, Globe, Square, Camera } from 'lucide-react';
import ReactMarkdown from 'react-markdown';
import remarkGfm from 'remark-gfm';
import { compressImage } from '../../utils/mediaHelpers';
import { parseDocument } from '../../utils/documentParser';
import { Toast, ToastState } from '../Toast';

interface WorkAssistantPanelProps {
    currentUser: User | null;
}

// Optimized Roles for Formal School Context
const ROLES = [
    { 
        id: 'editor', 
        name: '公众号图文精修', 
        icon: '📝', 
        description: '自动优化文稿并智能排版图片',
        prompt: `你是一位拥有10年经验的学校官方公众号主编。你的任务是根据用户提供的草稿（或活动描述）以及上传的图片，撰写一篇高质量的官方推文。

### 核心原则
1.  **文风要求**：端庄、大气、严谨，富有教育情怀。多用四字成语（如“精准赋能”、“蓄势扬帆”）。
2.  **严禁使用 Emoji**：保持学校官方文稿的严肃性，绝对不要出现任何表情包符号。
3.  **结构规范**：标题要对仗工整，正文要有层次感（如“校园寻迹”、“专题引领”等小标题）。
4.  **内容升华**：将具体活动上升到“立德树人”、“核心素养”、“高质量发展”等高度。

### 图片排版规则 (至关重要)
- **如果有图片**：用户上传了 {{IMAGE_COUNT}} 张图片。请务必将这 {{IMAGE_COUNT}} 张图片根据段落内容逻辑，以 **（图Start-图End）** 或 **（图N）** 的格式插入到文章最合适的位置。不要遗漏任何图片。
- **如果没有图片**：如果用户没有上传任何图片，**绝对不要**在文中插入任何 "(图x)" 占位符。直接输出纯文本文章即可。

### 输出风格示例
标题：精准赋能强基石 蓄势扬帆谋新篇
（正文段落，引用诗句或名言开篇...）
...校园每一处景观都被赋予了“微笑育人”的深刻内涵。（图1-图3）
...（小标题）...
...展现了跨学科融合的教学创新。（图4）`
    },
    { 
        id: 'host', 
        name: '活动主持/致辞', 
        icon: '🎤', 
        description: '生成正式的活动主持词',
        prompt: `你是一位经验丰富的学校活动策划和主持人。
协助老师撰写活动流程、主持稿或领导/嘉宾致辞。
1. **风格**：庄重、大气、热情但不失礼仪。**严禁使用 Emoji**。
2. **内容**：逻辑清晰，环节紧凑，串词自然过渡。
3. **格式**：标明【环节名称】、【具体话术】。` 
    },
    { 
        id: 'writer', 
        name: '公文/通知润色', 
        icon: '✍️', 
        description: '将草稿转化为正式公文',
        prompt: `你是一位资深的教育系统笔杆子。
请帮助老师将口语化或草稿文字转化为正式、规范的公文或通知。
1. **目标**：准确、简练、得体。**严禁使用 Emoji**。
2. **修正**：纠正错别字和语病，规范标点符号。
3. **格式**：符合公文通报的标准格式。` 
    },
    { 
        id: 'promoter', 
        name: '宣传/海报文案', 
        icon: '📢', 
        description: '生成精炼的宣传标语',
        prompt: `你是一位擅长教育传播的文案专家。
请为学校活动撰写短小精悍的宣传语，适用于海报、展板或家长群通知。
1. **长度**：200字以内。
2. **重点**：突出亮点，语言富有感染力，但保持端庄，不要使用过于浮夸的网络用语或 Emoji。
3. **排版**：分行排版，重点突出。` 
    },
    {
        id: 'lesson_planner',
        name: '智能教案生成',
        icon: '📚',
        description: '根据内容一键生成标准教案',
        prompt: `你是一位拥有20年教龄的特级教师和教研组长，熟悉新课标要求。
请根据用户提供的【教学内容】或【课文文章】，设计一份科学、严谨、符合教育教学规律的标准教案。

### 核心原则
1. **严禁使用 Emoji**：保持教案的专业性和严谨性。
2. **结构完整**：必须包含以下标准环节。
3. **以生为本**：体现学生的主体地位和核心素养的培养。

### 输出格式
**一、教学目标**
1. 知识与技能：...
2. 过程与方法：...
3. 情感态度与价值观：...

**二、教学重难点**
1. 重点：...
2. 难点：...

**三、教学方法**
（如：讲授法、讨论法、情境教学法等）

**四、教学过程**
1. **环节一：导入新课** (设计意图：...)
   - ...
2. **环节二：新课讲授** (设计意图：...)
   - ...
3. **环节三：巩固练习** (设计意图：...)
   - ...
4. **环节四：课堂小结**
   - ...
5. **环节五：作业布置** (分层作业)
   - ...

**五、板书设计**
（简洁明了的板书结构）`
    },
    {
        id: 'speech_maker',
        name: '演讲/说书稿',
        icon: '🎙️',
        description: '将资料转化为生动的讲稿',
        prompt: `你是一位金牌演讲撰稿人和故事讲述专家。
请根据用户提供的文本资料，将其改写为一份极具感染力、适合口头表达的【演讲稿】或【说书稿】。

### 核心原则
1. **严禁使用 Emoji**：保持文稿的文学性和正式感。
2. **口语化表达**：将书面语转化为听觉语言，多用短句，避免生僻词和冗长句式。
3. **情感共鸣**：注重情感的递进和渲染，使听众产生共鸣。

### 输出结构要求
1. **【开场白】**：用一个引人入胜的提问、故事或金句开场，迅速抓住听众注意力。
2. **【正文】**：
   - 逻辑清晰，层层递进。
   - 多用具体的细节描写和生动的例子，画面感强。
   - 适当加入“（停顿）”、“（重音）”、“（环视观众）”等演讲提示词，辅助老师表达。
3. **【结语】**：升华主题，发出号召或留下回味，给听众留下深刻印象。

### 风格要求
- 语言生动形象，抑扬顿挫。
- 根据内容定调：如果是说书，要有评书的韵味；如果是演讲，要有气势和感染力。`
    }
];

export const WorkAssistantPanel: React.FC<WorkAssistantPanelProps> = ({ currentUser }) => {
    const [selectedRole, setSelectedRole] = useState(ROLES[0]);
    const [enableThinking, setEnableThinking] = useState(false);
    const [enableSearch, setEnableSearch] = useState(false);
    const [isMobile, setIsMobile] = useState(false);
    
    const [messages, setMessages] = useState<AIChatMessage[]>([]);
    const [textInput, setTextInput] = useState('');
    const [selectedImages, setSelectedImages] = useState<File[]>([]);
    
    const [docFile, setDocFile] = useState<File | null>(null);
    const [docContent, setDocContent] = useState<string>('');
    const [docLoading, setDocLoading] = useState(false);

    const [isProcessing, setIsProcessing] = useState(false);
    
    const [toast, setToast] = useState<ToastState>({ show: false, message: '', type: 'success' });
    const [isThinkingExpanded, setIsThinkingExpanded] = useState<Record<string, boolean>>({});
    
    const messagesEndRef = useRef<HTMLDivElement>(null);
    const scrollContainerRef = useRef<HTMLDivElement>(null); 
    const fileInputRef = useRef<HTMLInputElement>(null);
    const cameraInputRef = useRef<HTMLInputElement>(null);
    const docInputRef = useRef<HTMLInputElement>(null);
    const abortControllerRef = useRef<AbortController | null>(null);

    // Smart Scroll & Check Mobile
    useEffect(() => {
        const checkMobile = () => {
            const userAgent = navigator.userAgent || navigator.vendor || (window as any).opera;
            const mobile = /android|webos|iphone|ipad|ipod|blackberry|iemobile|opera mini/i.test(userAgent.toLowerCase());
            setIsMobile(mobile);
        };
        checkMobile();

        if (!scrollContainerRef.current || !messagesEndRef.current) return;
        const container = scrollContainerRef.current;
        const { scrollTop, scrollHeight, clientHeight } = container;
        const isNearBottom = scrollHeight - scrollTop - clientHeight < 150;
        const lastMsg = messages[messages.length - 1];
        const isUserMsg = lastMsg?.role === 'user';

        if (isNearBottom || (isUserMsg && !isProcessing)) {
            messagesEndRef.current.scrollIntoView({ behavior: 'smooth', block: 'end' });
        }
    }, [messages, isProcessing, isThinkingExpanded]);

    const handleImageSelect = (e: React.ChangeEvent<HTMLInputElement>) => {
        if (e.target.files) {
            setSelectedImages(prev => [...prev, ...Array.from(e.target.files!)]);
        }
    };

    const handleDocSelect = async (e: React.ChangeEvent<HTMLInputElement>) => {
        if (e.target.files && e.target.files.length > 0) {
            const file = e.target.files[0];
            setDocFile(file);
            setDocLoading(true);
            try {
                const text = await parseDocument(file);
                setDocContent(text);
                setToast({ show: true, message: '文档解析成功，将作为参考内容发送', type: 'success' });
            } catch (err: any) {
                setToast({ show: true, message: '文档解析失败: ' + err.message, type: 'error' });
                setDocFile(null);
                setDocContent('');
            } finally {
                setDocLoading(false);
            }
        }
    };

    const clearDoc = () => {
        setDocFile(null);
        setDocContent('');
        if (docInputRef.current) docInputRef.current.value = '';
    };

    const handleCopy = (text: string) => {
        navigator.clipboard.writeText(text);
        setToast({ show: true, message: '内容已复制', type: 'success' });
    };

    const handleStopGeneration = () => {
        if (abortControllerRef.current) {
            abortControllerRef.current.abort();
            abortControllerRef.current = null;
            setIsProcessing(false);
            setToast({ show: true, message: '已停止生成', type: 'error' });
        }
    };

    const handleSubmit = async () => {
        if ((!textInput.trim() && selectedImages.length === 0 && !docContent) || isProcessing) return;
        
        setIsProcessing(true);
        const currentText = textInput;
        const currentImages = [...selectedImages];
        const currentDocText = docContent;
        const currentDocName = docFile?.name;
        
        setTextInput('');
        setSelectedImages([]);
        clearDoc();
        
        abortControllerRef.current = new AbortController();

        const userMsgId = crypto.randomUUID();
        const aiMsgId = crypto.randomUUID();

        try {
            const base64Images = await Promise.all(currentImages.map(f => compressImage(f)));

            const newUserMsg: AIChatMessage = { 
                id: userMsgId, 
                role: 'user', 
                text: currentText + (currentDocName ? `\n\n[附带文档]: ${currentDocName}` : ''), 
                images: base64Images, 
                timestamp: Date.now() 
            };
            
            const newAiMsg: AIChatMessage = { 
                id: aiMsgId, 
                role: 'model', 
                text: '', 
                thought: '', 
                timestamp: Date.now(),
                images: base64Images,
                isSearching: enableSearch 
            };

            setMessages(prev => [...prev, newUserMsg, newAiMsg]);
            
            setTimeout(() => {
                messagesEndRef.current?.scrollIntoView({ behavior: 'smooth', block: 'end' });
            }, 100);
            
            if (enableThinking) {
                setIsThinkingExpanded(prev => ({ ...prev, [aiMsgId]: true }));
            }

            const dynamicSystemPrompt = selectedRole.prompt.replace(/{{IMAGE_COUNT}}/g, String(base64Images.length));

            let finalPrompt = currentText;
            
            if (currentDocText) {
                finalPrompt += `\n\n【参考文档内容 (${currentDocName})】:\n${currentDocText}\n\n请根据上述文档内容和我的要求进行创作。`;
            }

            if (base64Images.length > 0) {
                finalPrompt += `\n\n[系统提示] 用户上传了 ${base64Images.length} 张图片。请务必在文章中合理位置插入 （图1-图X） 格式的占位符。`;
            } else {
                finalPrompt += `\n\n[系统提示] 用户未上传图片。请忽略所有图片排版指令，严禁在文中插入任何 (图x) 占位符，仅输出纯文字。`;
            }

            const response = await fetch('/api/ai/chat', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json',
                    'x-user-username': currentUser?.username || '',
                    'x-user-role': currentUser?.role || '',
                    'x-school-id': currentUser?.schoolId || ''
                },
                body: JSON.stringify({ 
                    text: finalPrompt, 
                    images: base64Images, 
                    history: [], 
                    enableThinking,
                    enableSearch,
                    overrideSystemPrompt: dynamicSystemPrompt, 
                    disableAudio: true 
                }),
                signal: abortControllerRef.current.signal
            });

            if (!response.ok) throw new Error(response.statusText);
            if (!response.body) throw new Error('No response body');

            const reader = response.body.getReader();
            const decoder = new TextDecoder();
            let aiTextAccumulated = '';
            let aiThoughtAccumulated = '';
            let buffer = '';

            while (true) {
                const { done, value } = await reader.read();
                if (done) break;
                
                buffer += decoder.decode(value, { stream: true });
                const parts = buffer.split('\n\n');
                buffer = parts.pop() || ''; 
                
                for (const line of parts) {
                    if (line.startsWith('data: ')) {
                        const jsonStr = line.replace('data: ', '').trim();
                        if (jsonStr === '[DONE]') break;
                        
                        try {
                            const data = JSON.parse(jsonStr);
                            
                            if (data.type === 'thinking') {
                                aiThoughtAccumulated += data.content;
                                setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, thought: aiThoughtAccumulated } : m));
                            } else if (data.type === 'text') {
                                if (aiTextAccumulated === '' && aiThoughtAccumulated !== '') {
                                    setIsThinkingExpanded(prev => ({ ...prev, [aiMsgId]: false }));
                                }
                                aiTextAccumulated += data.content;
                                setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, text: aiTextAccumulated, isSearching: false } : m));
                            } else if (data.type === 'search') {
                                setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, isSearching: true } : m));
                            } else if (data.type === 'error') {
                                setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, text: `⚠️ 错误: ${data.message}`, isSearching: false } : m));
                            }
                        } catch (e) {}
                    }
                }
            }

        } catch (error: any) {
            if (error.name !== 'AbortError') {
                setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, text: `抱歉，处理失败: ${error.message}`, isSearching: false } : m));
            }
        } finally {
            setMessages(prev => prev.map(m => m.id === aiMsgId ? { ...m, isSearching: false } : m));
            setIsProcessing(false);
            abortControllerRef.current = null;
        }
    };

    const renderContent = (text: string, sourceImages: string[] | undefined) => {
        if (!sourceImages || sourceImages.length === 0) {
            return <ReactMarkdown remarkPlugins={[remarkGfm]}>{text}</ReactMarkdown>;
        }

        const splitRegex = /(（?图\d+(?:-图\d+)?）?)/g;
        const parts = text.split(splitRegex);

        return (
            <div>
                {parts.map((part, idx) => {
                    const rangeMatch = part.match(/图(\d+)-图(\d+)/); 
                    const singleMatch = part.match(/图(\d+)/); 

                    if (rangeMatch) {
                        const start = parseInt(rangeMatch[1]);
                        const end = parseInt(rangeMatch[2]);
                        const imagesToShow: string[] = [];
                        
                        for (let i = start; i <= end; i++) {
                            if (sourceImages[i-1]) imagesToShow.push(sourceImages[i-1]);
                        }

                        if (imagesToShow.length > 0) {
                            return (
                                <div key={idx} className="my-4 bg-gray-50 p-2 rounded-lg border border-gray-100">
                                    <div className="grid grid-cols-2 md:grid-cols-3 gap-2">
                                        {imagesToShow.map((img, i) => (
                                            <div key={i} className="relative aspect-[4/3] group">
                                                <img src={`data:image/jpeg;base64,${img}`} className="w-full h-full object-cover rounded-md cursor-pointer hover:opacity-90 transition-opacity" title={`图 ${start+i}`}/>
                                                <div className="absolute bottom-1 right-1 bg-black/60 text-white text-[10px] px-1.5 rounded">图 {start+i}</div>
                                            </div>
                                        ))}
                                    </div>
                                    <div className="text-center text-xs text-gray-400 mt-2 font-mono">{part}</div>
                                </div>
                            );
                        }
                    } else if (singleMatch && !part.includes('-')) {
                        const imgIndex = parseInt(singleMatch[1]) - 1;
                        if (sourceImages[imgIndex]) {
                            return (
                                <div key={idx} className="my-4 flex flex-col items-center">
                                    <img 
                                        src={`data:image/jpeg;base64,${sourceImages[imgIndex]}`} 
                                        className="max-w-full md:max-w-sm rounded-lg shadow-sm border border-gray-200" 
                                        alt={`Image ${imgIndex + 1}`} 
                                    />
                                    <div className="text-center text-xs text-gray-400 mt-1 font-mono">{part}</div>
                                </div>
                            );
                        }
                    }
                    return <ReactMarkdown key={idx} remarkPlugins={[remarkGfm]} components={{p: ({node, ...props}) => <p className="mb-2 last:mb-0 inline" {...props}/>}}>{part}</ReactMarkdown>;
                })}
            </div>
        );
    };

    return (
        <div className="flex flex-col h-full bg-slate-50 relative">
            {toast.show && <Toast message={toast.message} type={toast.type} onClose={()=>setToast({...toast, show: false})}/>}
            
            <div className="bg-white px-6 py-3 border-b border-gray-200 flex flex-wrap gap-4 items-center justify-between shadow-sm shrink-0 z-20">
                <div className="flex items-center gap-2">
                    <span className="text-sm font-bold text-gray-700">工作模式:</span>
                    <div className="relative group">
                        <button className="flex items-center gap-2 px-3 py-1.5 bg-indigo-50 text-indigo-700 rounded-lg text-sm font-bold border border-indigo-100 hover:bg-indigo-100 transition-colors">
                            <span>{selectedRole.icon} {selectedRole.name}</span>
                            <ChevronDown size={14}/>
                        </button>
                        <div className="absolute top-full left-0 mt-1 w-64 bg-white border border-gray-200 rounded-xl shadow-xl overflow-hidden hidden group-hover:block z-50">
                            {ROLES.map(role => (
                                <button 
                                    key={role.id}
                                    onClick={() => setSelectedRole(role)}
                                    className={`w-full text-left px-4 py-3 hover:bg-indigo-50 flex items-start gap-3 border-b border-gray-50 last:border-0 ${selectedRole.id === role.id ? 'bg-indigo-50' : ''}`}
                                >
                                    <div className="text-xl mt-0.5">{role.icon}</div>
                                    <div>
                                        <div className={`text-sm font-bold ${selectedRole.id === role.id ? 'text-indigo-700' : 'text-gray-800'}`}>{role.name}</div>
                                        <div className="text-xs text-gray-500 mt-0.5">{role.description}</div>
                                    </div>
                                </button>
                            ))}
                        </div>
                    </div>
                </div>

                <div className="flex items-center gap-3">
                    <div className="flex items-center gap-1" title="开启后AI会进行更深入的逻辑推演">
                        <label className="relative inline-flex items-center cursor-pointer">
                            <input type="checkbox" checked={enableThinking} onChange={e => setEnableThinking(e.target.checked)} className="sr-only peer"/>
                            <div className="w-9 h-5 bg-gray-200 peer-focus:outline-none rounded-full peer peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-gray-300 after:border after:rounded-full after:h-4 after:w-4 after:transition-all peer-checked:bg-purple-600"></div>
                        </label>
                        <span className="text-xs text-gray-600 font-bold">深度思考</span>
                    </div>
                    <div className="flex items-center gap-1" title="开启联网搜索">
                        <label className="relative inline-flex items-center cursor-pointer">
                            <input type="checkbox" checked={enableSearch} onChange={e => setEnableSearch(e.target.checked)} className="sr-only peer"/>
                            <div className="w-9 h-5 bg-gray-200 peer-focus:outline-none rounded-full peer peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-gray-300 after:border after:rounded-full after:h-4 after:w-4 after:transition-all peer-checked:bg-blue-600"></div>
                        </label>
                        <span className="text-xs text-gray-600 font-bold">联网搜索</span>
                    </div>
                    <div className="w-px h-6 bg-gray-200 mx-1"></div>
                    <button onClick={() => setMessages([])} className="text-gray-400 hover:text-red-500 p-2 rounded-full hover:bg-red-50 transition-colors" title="清空对话">
                        <Trash2 size={18}/>
                    </button>
                </div>
            </div>

            <div ref={scrollContainerRef} className="flex-1 overflow-y-auto p-6 space-y-6 custom-scrollbar">
                {messages.length === 0 && (
                    <div className="flex flex-col items-center justify-center h-full text-gray-400 opacity-60">
                        <FileText size={48} className="mb-4 text-indigo-300"/>
                        <p className="text-lg font-bold text-gray-600">我是你的{selectedRole.name}助理</p>
                        <p className="text-sm mt-2 max-w-md text-center">
                            请上传活动照片（支持批量）或文档（Word/PDF/Txt）<br/>
                            输入简单的活动描述，我会为你生成端庄大气的官方文稿。
                        </p>
                    </div>
                )}
                
                {messages.map((msg, index) => {
                    let sourceImages: string[] = msg.images || [];
                    
                    if (msg.role === 'model' && (!sourceImages || sourceImages.length === 0)) {
                        const prevMsg = messages[index - 1];
                        if (prevMsg && prevMsg.role === 'user' && prevMsg.images) {
                            sourceImages = prevMsg.images;
                        }
                    }

                    return (
                        <div key={msg.id} className={`flex gap-4 ${msg.role === 'user' ? 'flex-row-reverse' : ''} max-w-5xl mx-auto w-full`}>
                            <div className={`w-10 h-10 rounded-full flex items-center justify-center shrink-0 shadow-sm ${msg.role === 'model' ? 'bg-white border border-indigo-100 text-indigo-600' : 'bg-blue-600 text-white'}`}>
                                {msg.role === 'model' ? <Sparkles size={20}/> : <span className="font-bold text-xs">ME</span>}
                            </div>
                            
                            <div className={`flex flex-col gap-2 max-w-[90%] ${msg.role === 'user' ? 'items-end' : 'items-start'}`}>
                                {msg.role === 'model' && msg.thought && (
                                    <div className="w-full bg-purple-50 rounded-xl border border-purple-100 overflow-hidden mb-2">
                                        <button 
                                            onClick={() => setIsThinkingExpanded(prev => ({ ...prev, [msg.id]: !prev[msg.id] }))}
                                            className="w-full px-4 py-2 flex items-center justify-between text-xs font-bold text-purple-700 bg-purple-100/50 hover:bg-purple-100 transition-colors"
                                        >
                                            <span className="flex items-center gap-2"><Brain size={14}/> 深度思考过程</span>
                                            {isThinkingExpanded[msg.id] ? <ChevronDown size={14}/> : <ChevronRight size={14}/>}
                                        </button>
                                        {isThinkingExpanded[msg.id] && (
                                            <div className="p-4 text-xs text-purple-800 whitespace-pre-wrap leading-relaxed border-t border-purple-100 font-mono bg-white/50">
                                                {msg.thought}
                                            </div>
                                        )}
                                    </div>
                                )}

                                {msg.role === 'model' && msg.isSearching && (
                                    <div className="flex items-center gap-2 bg-blue-50 text-blue-600 px-3 py-2 rounded-xl mb-2 text-xs border border-blue-100 animate-pulse w-fit">
                                        <Globe size={14} className="animate-spin"/>
                                        <span>正在联网搜索相关信息...</span>
                                    </div>
                                )}

                                <div className={`p-5 rounded-2xl shadow-sm text-sm overflow-hidden relative group w-full ${msg.role === 'user' ? 'bg-blue-600 text-white rounded-tr-none' : 'bg-white text-gray-800 border border-gray-100 rounded-tl-none'}`}>
                                    {msg.role === 'user' && sourceImages.length > 0 && (
                                        <div className="grid grid-cols-4 gap-2 mb-3">
                                            {sourceImages.map((img, i) => (
                                                <div key={i} className="relative aspect-square">
                                                    <img src={`data:image/jpeg;base64,${img}`} className="w-full h-full object-cover rounded-lg border border-white/20" />
                                                    <div className="absolute bottom-0 right-0 bg-black/50 text-white text-[10px] px-1.5 rounded-tl-lg">图{i+1}</div>
                                                </div>
                                            ))}
                                        </div>
                                    )}

                                    <div className={`markdown-body ${msg.role === 'user' ? 'text-white' : ''}`}>
                                        {msg.role === 'model' ? renderContent(msg.text || '', sourceImages) : <p className="whitespace-pre-wrap">{msg.text}</p>}
                                    </div>

                                    {msg.role === 'model' && !isProcessing && (
                                        <button 
                                            onClick={() => handleCopy(msg.text || '')} 
                                            className="absolute top-2 right-2 p-1.5 text-gray-400 hover:text-blue-600 bg-white/80 backdrop-blur rounded-lg opacity-0 group-hover:opacity-100 transition-all shadow-sm border border-gray-100"
                                            title="复制纯文本"
                                        >
                                            <Copy size={14}/>
                                        </button>
                                    )}
                                </div>
                            </div>
                        </div>
                    );
                })}
                {isProcessing && (
                    <div className="flex justify-center py-4">
                        <div className="bg-white px-4 py-2 rounded-full shadow-sm border border-indigo-100 flex items-center gap-2 text-indigo-600 text-sm animate-pulse">
                            <Bot size={16}/>
                            <span>正在阅读资料并撰写文案...</span>
                        </div>
                    </div>
                )}
                <div ref={messagesEndRef} />
            </div>

            <div className="bg-white border-t border-gray-200 p-4 z-20">
                <div className="max-w-4xl mx-auto flex flex-col gap-3">
                    {(selectedImages.length > 0 || docFile) && (
                        <div className="flex gap-2 overflow-x-auto pb-2 px-1 custom-scrollbar">
                            {selectedImages.map((file, idx) => (
                                <div key={idx} className="relative w-16 h-16 shrink-0 group rounded-lg overflow-hidden border border-gray-200 shadow-sm">
                                    <img src={URL.createObjectURL(file)} className="w-full h-full object-cover" />
                                    <div className="absolute inset-0 bg-black/40 opacity-0 group-hover:opacity-100 transition-opacity flex items-center justify-center cursor-pointer" onClick={() => setSelectedImages(prev => prev.filter((_, i) => i !== idx))}>
                                        <X size={16} className="text-white"/>
                                    </div>
                                    <div className="absolute bottom-0 right-0 bg-blue-600 text-white text-[9px] px-1 rounded-tl">图{idx+1}</div>
                                </div>
                            ))}
                            {docFile && (
                                <div className="relative h-16 px-3 bg-indigo-50 border border-indigo-200 rounded-lg flex items-center justify-center shrink-0 min-w-[120px] max-w-[200px]">
                                    <div className="flex flex-col items-start overflow-hidden">
                                        <div className="flex items-center text-indigo-700 font-bold text-xs mb-1">
                                            <File size={12} className="mr-1"/> 
                                            {docLoading ? '解析中...' : '已解析'}
                                        </div>
                                        <span className="text-[10px] text-indigo-500 truncate w-full" title={docFile.name}>{docFile.name}</span>
                                    </div>
                                    <button onClick={clearDoc} className="absolute top-0.5 right-0.5 text-indigo-300 hover:text-red-500 p-0.5"><X size={12}/></button>
                                </div>
                            )}
                        </div>
                    )}

                    <div className="flex gap-2 items-end bg-gray-50 p-2 rounded-2xl border border-gray-200 focus-within:ring-2 focus-within:ring-indigo-100 focus-within:border-indigo-300 transition-all shadow-inner">
                        <div className="flex items-center">
                            <button onClick={() => fileInputRef.current?.click()} className="p-2 text-gray-500 hover:bg-white hover:text-blue-600 rounded-full transition-colors shrink-0" title="相册/文件">
                                <ImageIcon size={22}/>
                            </button>
                            {isMobile && (
                                <button onClick={() => cameraInputRef.current?.click()} className="p-2 text-gray-500 hover:bg-white hover:text-blue-600 rounded-full transition-colors shrink-0" title="拍照">
                                    <Camera size={22}/>
                                </button>
                            )}
                        </div>
                        
                        <input type="file" multiple accept="image/*" ref={fileInputRef} className="hidden" onChange={handleImageSelect} onClick={(e) => (e.currentTarget.value = '')} />
                        
                        {isMobile && (
                            <input type="file" accept="image/*" capture="environment" ref={cameraInputRef} className="hidden" onChange={handleImageSelect} onClick={(e) => (e.currentTarget.value = '')} />
                        )}

                        <button onClick={() => docInputRef.current?.click()} className={`p-2 rounded-full transition-colors shrink-0 ${docFile ? 'text-indigo-600 bg-indigo-50' : 'text-gray-500 hover:bg-white hover:text-indigo-600'}`} title="上传文档 (Docx, PDF, Txt)">
                            <Paperclip size={22}/>
                        </button>
                        <input type="file" accept=".docx, .pdf, .txt" ref={docInputRef} className="hidden" onChange={handleDocSelect} onClick={(e) => (e.currentTarget.value = '')} />

                        <textarea 
                            className="flex-1 bg-transparent border-none outline-none text-sm resize-none max-h-32 py-3 px-2"
                            placeholder={selectedRole.id === 'editor' ? "请输入活动描述，或直接上传活动方案文档..." : `给${selectedRole.name}下达指令...`}
                            rows={1}
                            value={textInput}
                            onChange={e => setTextInput(e.target.value)}
                            onKeyDown={e => { if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); handleSubmit(); } }}
                        />

                        {isProcessing ? (
                            <button 
                                onClick={handleStopGeneration} 
                                className="p-3 bg-red-500 text-white rounded-xl shadow-sm hover:bg-red-600 transition-all shrink-0 animate-pulse"
                                title="停止生成"
                            >
                                <Square size={20} fill="currentColor"/>
                            </button>
                        ) : (
                            <button 
                                onClick={handleSubmit}
                                onMouseDown={(e) => e.preventDefault()}
                                onTouchEnd={(e) => { e.preventDefault(); handleSubmit(); }}
                                type="button"
                                disabled={(!textInput.trim() && selectedImages.length === 0 && !docFile) || isProcessing || docLoading}
                                className={`p-3 rounded-xl transition-all shrink-0 shadow-sm ${(!textInput.trim() && selectedImages.length === 0 && !docFile) || isProcessing || docLoading ? 'bg-gray-200 text-gray-400 cursor-not-allowed' : 'bg-indigo-600 text-white hover:bg-indigo-700 hover:scale-105'}`}
                            >
                                {isProcessing || docLoading ? <Loader2 className="animate-spin" size={20}/> : <Send size={20}/>}
                            </button>
                        )}
                    </div>
                    <div className="flex justify-between text-xs text-gray-400 px-1">
                        <span>* 支持上传 Word/PDF/Txt 解析内容</span>
                        <span>AI 生成内容仅供参考</span>
                    </div>
                </div>
            </div>
        </div>
    );
};