'use client';

import { useState, useRef, useEffect, FormEvent, Suspense } from 'react';
import Link from 'next/link';
import { useSearchParams } from 'next/navigation';
import { useAuth } from '@/lib/auth-context';
import { getToken, apiFetch } from '@/lib/auth';
import { DEFAULT_MODEL } from '@/lib/models';
import { ModelSelector } from '@/components/ui/model-selector';
import { useT } from '@/i18n';
import { CodeBlock } from '@/components/ui/code-block';
import { API_BASE } from '@/lib/config';

interface Message {
  role: 'system' | 'user' | 'assistant';
  content: string;
}

interface SessionItem {
  id: number;
  conversationId: string;
  model: string;
  title: string;
  createdAt: string;
  tokens: number;
}

function extractCodeBlocks(content: string): string[] {
  const blocks: string[] = [];
  const regex = /```(?:\w+)?\n([\s\S]*?)```/g;
  let match;
  while ((match = regex.exec(content)) !== null) {
    const code = match[1].trim();
    if (code.length > 0) blocks.push(code);
  }
  return blocks;
}

export default function SandboxPageWrapper() {
  return (
    <Suspense fallback={
      <div className="max-w-6xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
        <div className="h-8 w-48 bg-muted rounded-lg animate-pulse mb-4" />
        <div className="h-[65vh] bg-muted rounded-2xl animate-pulse" />
      </div>
    }>
      <SandboxPage />
    </Suspense>
  );
}

function SandboxPage() {
  const searchParams = useSearchParams();
  const t = useT();
  const [messages, setMessages] = useState<Message[]>([
    { role: 'assistant', content: '你好！我是宇之然 AI 助手。你可以问我任何问题，我会尽力帮你解答。\n\n试试问我关于 AI、编程、写作、办公效率等方面的问题！' },
  ]);
  const [input, setInput] = useState('');
  const [model, setModel] = useState(DEFAULT_MODEL);
  const [scene, setScene] = useState('');
  const [SCENES, setSCENES] = useState<{ id: string; name: string; icon: string; systemPrompt: string; starters: string[] }[]>([]);
  const [skillsLoading, setSkillsLoading] = useState(true);
  const [sending, setSending] = useState(false);
  const [showParams, setShowParams] = useState(false);
  const [temperature, setTemperature] = useState(0.7);
  const [topP, setTopP] = useState(1);
  const [maxTokens, setMaxTokens] = useState(2000);
  const [quota, setQuota] = useState<{ used: number; remaining: number } | null>(null);
  const [sessions, setSessions] = useState<SessionItem[]>([]);
  const [sessionsOpen, setSessionsOpen] = useState(false);
  const [searchQuery, setSearchQuery] = useState('');
  const [conversationId, setConversationId] = useState(() => crypto.randomUUID());
  const [sessionFeedback, setSessionFeedback] = useState<Record<number, string | null>>({});
  const [currentSessionId, setCurrentSessionId] = useState<number | null>(null);
  const [renamingId, setRenamingId] = useState<number | null>(null);
  const [renameValue, setRenameValue] = useState('');
  const [uploadedImages, setUploadedImages] = useState<string[]>([]);
  const [uploading, setUploading] = useState(false);
  const fileInputRef = useRef<HTMLInputElement>(null);
  const messagesEndRef = useRef<HTMLDivElement>(null);
  const messagesContainerRef = useRef<HTMLDivElement>(null);
  const { isLoggedIn } = useAuth();

  useEffect(() => {
    const tk = getToken();
    if (tk) {
      fetch(`${API_BASE}/sandbox/quota`, {
        headers: { Authorization: `Bearer ${tk}` },
      }).then(r => r.json()).then(data => {
        if (data.remaining !== undefined) setQuota(data);
      }).catch(() => {});
      loadSessions(tk);
    }
  }, [isLoggedIn]);

  useEffect(() => {
    fetch(`${API_BASE}/skills`)
      .then(r => r.json())
      .then(data => {
        const scenes = (data.items || []).map((s: any) => ({ id: s.id, name: s.name, icon: s.icon, systemPrompt: s.systemPrompt, starters: s.starters }));
        setSCENES(scenes);
        const skillParam = searchParams.get('skill');
        const initialScene = scenes.find((s: any) => s.id === skillParam) ? skillParam : (scenes[0]?.id || '');
        setScene(initialScene);
      })
      .finally(() => setSkillsLoading(false));
  }, []);

  useEffect(() => {
    if (messages.some(m => m.role === 'user') && messagesContainerRef.current) {
      messagesContainerRef.current.scrollTop = messagesContainerRef.current.scrollHeight;
    }
  }, [messages]);

  function loadSessions(tk?: string) {
    const token = tk || getToken();
    if (!token) return;
    const params = searchQuery ? `?search=${encodeURIComponent(searchQuery)}` : '';
    fetch(`${API_BASE}/sandbox/sessions${params}`, {
      headers: { Authorization: `Bearer ${token}` },
    }).then(r => r.json()).then(data => {
      if (data.items) setSessions(data.items);
    }).catch(() => {});
  }

  function handleSceneChange(sceneId: string) {
    setScene(sceneId);
    const s = SCENES.find(x => x.id === sceneId);
    setMessages([
      { role: 'assistant', content: `欢迎来到 **${s?.name || sceneId}** 模式！试试下面的问题，或者直接输入你的问题吧。` },
    ]);
  }

  async function handleSend(e: FormEvent) {
    e.preventDefault();
    const text = input.trim();
    if (!text || sending) return;

    const userMsg: Message = { role: 'user', content: text };
    setMessages(prev => [...prev, userMsg]);
    setInput('');
    setSending(true);

    try {
      const tk = getToken();
      let reply = '';
      if (tk) {
        const curScene = SCENES.find(s => s.id === scene) || SCENES[0];
        const systemPrompt = curScene?.systemPrompt || '你是一个智能 AI 助手';
        const apiMessages = [
          { role: 'system', content: systemPrompt },
          ...messages,
          userMsg,
        ].map(m => ({ role: m.role, content: m.content }));

        const res = await fetch(`${API_BASE}/sandbox/chat`, {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
            Authorization: `Bearer ${tk}`,
          },
          body: JSON.stringify({ conversationId, model, messages: apiMessages, temperature, top_p: topP, max_tokens: maxTokens, ...(uploadedImages.length > 0 ? { images: uploadedImages } : {}) }),
        });
        const data = await res.json();
        if (!res.ok) throw new Error(data.message || '请求失败');
        reply = data.reply;
        if (data.conversationId) setConversationId(data.conversationId);
        if (data.sessionId) setCurrentSessionId(data.sessionId);
        if (quota) setQuota({ ...quota, used: quota.used + 1, remaining: quota.remaining - 1 });
        setUploadedImages([]);
        loadSessions(tk);
      } else {
        await new Promise(r => setTimeout(r, 300));
        reply = '📝 注册登录后可体验完整 AI 对话功能。\n\n点击右上角「登录」或「注册」即可开始使用。';
      }

      setMessages(prev => [...prev, { role: 'assistant', content: reply }]);
    } catch (e: any) {
      if (e.message.includes('今日沙箱使用次数已用完')) {
        setMessages(prev => [...prev, { role: 'assistant', content: '今日沙箱使用次数已用完。' + (isLoggedIn ? '' : ' 登录后可获得更多使用次数。') }]);
      } else if (e.message.includes('未登录') || e.message.includes('Unauthorized')) {
        setMessages(prev => [...prev, { role: 'assistant', content: '登录已过期，请重新登录后再试。' }]);
      } else {
        setMessages(prev => [...prev, { role: 'assistant', content: `出错啦：${e.message}` }]);
      }
    } finally {
      setSending(false);
    }
  }

  async function loadSession(sessionId: number) {
    const tk = getToken();
    if (!tk) return;
    try {
      const res = await fetch(`${API_BASE}/sandbox/sessions/${sessionId}`, {
        headers: { Authorization: `Bearer ${tk}` },
      });
      const data = await res.json();
      if (data.messages) {
        setMessages(data.messages.filter((m: any) => m.role !== 'system'));
        setModel(data.model);
        setConversationId(data.conversationId);
        setCurrentSessionId(data.id);
        setSessionFeedback(prev => ({ ...prev, [data.id]: data.feedback || null }));
      }
    } catch {}
  }

  async function deleteSession(sessionId: number) {
    const tk = getToken();
    if (!tk) return;
    try {
      await fetch(`${API_BASE}/sandbox/sessions/${sessionId}`, {
        method: 'DELETE',
        headers: { Authorization: `Bearer ${tk}` },
      });
      setSessions(prev => prev.filter(s => s.id !== sessionId));
    } catch {}
  }

  async function renameSession(sessionId: number, title: string) {
    const tk = getToken();
    if (!tk || !title.trim()) return;
    try {
      await fetch(`${API_BASE}/sandbox/sessions/${sessionId}/rename`, {
        method: 'PATCH',
        headers: { 'Content-Type': 'application/json', Authorization: `Bearer ${tk}` },
        body: JSON.stringify({ title: title.trim() }),
      });
      setSessions(prev => prev.map(s => s.id === sessionId ? { ...s, title: title.trim() } : s));
      setRenamingId(null);
    } catch {}
  }

  function newChat() {
    setConversationId(crypto.randomUUID());
    setCurrentSessionId(null);
    const s = SCENES.find(x => x.id === scene);
    setMessages([
      { role: 'assistant', content: `欢迎来到 **${s?.name || scene}** 模式！试试下面的问题，或者直接输入你的问题吧。` },
    ]);
  }

  async function handleFeedback(sessionId: number, value: 'LIKE' | 'DISLIKE') {
    const tk = getToken();
    if (!tk) return;
    const newVal = sessionFeedback[sessionId] === value ? null : value;
    setSessionFeedback(prev => ({ ...prev, [sessionId]: newVal }));
    try {
      await fetch(`${API_BASE}/sandbox/sessions/${sessionId}/feedback`, {
        method: 'PATCH',
        headers: { 'Content-Type': 'application/json', Authorization: `Bearer ${tk}` },
        body: JSON.stringify({ feedback: newVal }),
      });
    } catch {}
  }

  function formatTime(dateStr: string) {
    const d = new Date(dateStr);
    const now = new Date();
    const diff = now.getTime() - d.getTime();
    if (diff < 60000) return t.sandbox.justNow;
    if (diff < 3600000) return t.sandbox.minutesAgo.replace('{n}', String(Math.floor(diff / 60000)));
    if (diff < 86400000) return t.sandbox.hoursAgo.replace('{n}', String(Math.floor(diff / 3600000)));
    return `${d.getMonth() + 1}/${d.getDate()} ${d.getHours().toString().padStart(2, '0')}:${d.getMinutes().toString().padStart(2, '0')}`;
  }

  async function shareSessionLink() {
    if (!getToken() || !currentSessionId) { alert('请先登录'); return; }
    try {
      const tk = getToken();
      const res = await fetch(`${API_BASE}/sandbox/sessions/${currentSessionId}/share`, {
        method: 'POST', headers: { Authorization: `Bearer ${tk}` },
      });
      const data = await res.json();
      if (data.shareUrl) {
        await navigator.clipboard.writeText(data.shareUrl);
        alert('链接已复制');
      }
    } catch { alert('生成分享链接失败'); }
  }

  function shareToCommunity(content: string, title?: string) {
    if (!getToken()) { alert('请先登录'); return; }
    apiFetch('/community/posts', {
      method: 'POST',
      body: JSON.stringify({
        title: title || `AI对话分享 - ${new Date().toLocaleDateString()}`,
        content: `【AI沙箱对话分享】\n\n${content}\n\n---\n来自宇之然AI沙箱`,
        tags: '沙箱分享,AI对话',
      }),
    }).then(() => alert('分享成功！')).catch(() => alert('分享失败'));
  }

  const currentScene = SCENES.find(s => s.id === scene) || SCENES[0] || null;

  if (skillsLoading) return (
    <div className="max-w-6xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
      <div className="animate-pulse space-y-4">
        <div className="h-8 w-48 bg-muted rounded-lg" />
        <div className="h-[65vh] bg-muted rounded-2xl" />
      </div>
    </div>
  );
  const isNewChat = messages.length <= 1 && messages[0]?.role === 'assistant';

  return (
    <div className="max-w-6xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
      <div className="flex items-center justify-between mb-4">
        <div className="flex items-center gap-3">
          <button onClick={() => setSessionsOpen(!sessionsOpen)}
            className="lg:hidden p-2 text-muted-foreground hover:text-foreground rounded-lg hover:bg-accent">
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 6h16M4 12h16M4 18h16" />
            </svg>
          </button>
          <div>
            <h1 className="text-2xl font-bold text-foreground">{t.sandbox.title}</h1>
            <p className="text-sm text-muted-foreground mt-0.5">{t.sandbox.subtitle}</p>
          </div>
        </div>
        <div className="flex flex-wrap items-center gap-2 sm:gap-3">
          <ModelSelector value={model} onChange={setModel} className="w-40 sm:w-48" />
          {!isLoggedIn && (
            <Link href="/auth"
              className="px-4 py-1.5 text-sm font-medium text-brand-600 border border-brand-200 rounded-lg hover:bg-brand-50">
              {t.sandbox.loginForMore}
            </Link>
          )}
        </div>
      </div>

      <div className="flex gap-4">
        {isLoggedIn && (
          <>
            <div className={`${sessionsOpen ? 'fixed inset-0 z-40 bg-black/50 lg:static lg:bg-transparent' : 'hidden'} lg:block lg:w-72 shrink-0`}>
              <div className={`${sessionsOpen ? 'fixed left-0 top-0 bottom-0 w-80 z-50' : ''} lg:static lg:w-72 bg-card border border-border rounded-2xl overflow-hidden flex flex-col`} style={{ maxHeight: '75vh' }}>
                <div className="p-3 border-b border-border flex items-center justify-between">
                  <span className="text-sm font-medium text-foreground">{t.sandbox.history}</span>
                  <button onClick={newChat}
                    className="text-xs px-3 py-1 bg-brand-600 text-white rounded-lg hover:bg-brand-700">
                    {t.sandbox.newChat}
                  </button>
                </div>
                <div className="p-2 border-b border-border">
                  <input type="text" value={searchQuery} onChange={e => setSearchQuery(e.target.value)}
                    placeholder={t.sandbox.searchHistory} onKeyDown={e => { if (e.key === 'Enter') loadSessions(); }}
                    className="w-full px-3 py-1.5 bg-background border border-border rounded-lg text-xs focus:outline-none focus:border-brand-400" />
                </div>
                <div className="flex-1 overflow-y-auto">
                  {sessions.length === 0 ? (
                    <div className="p-4 text-center text-xs text-muted-foreground">{t.sandbox.noHistory}</div>
                  ) : sessions.map(s => (
                      <div key={s.id} onClick={() => { if (renamingId !== s.id) { loadSession(s.id); setSessionsOpen(false); } }}
                        className="group px-3 py-2.5 hover:bg-accent cursor-pointer border-b border-border/50"
                        onDoubleClick={() => { setRenamingId(s.id); setRenameValue(s.title); }}>
                        {renamingId === s.id ? (
                          <input type="text" value={renameValue} onChange={e => setRenameValue(e.target.value)}
                            autoFocus onClick={e => e.stopPropagation()}
                            onBlur={() => renameSession(s.id, renameValue)}
                            onKeyDown={e => { if (e.key === 'Enter') { e.stopPropagation(); renameSession(s.id, renameValue); } if (e.key === 'Escape') setRenamingId(null); }}
                            className="w-full px-1 py-0.5 text-xs font-medium bg-background border border-border rounded focus:outline-none" />
                        ) : (
                          <div className="text-xs font-medium text-foreground truncate">{s.title}</div>
                        )}
                      <div className="flex items-center justify-between mt-1">
                        <span className="text-[10px] text-muted-foreground">{formatTime(s.createdAt)} · {s.model}</span>
                        <button onClick={e => { e.stopPropagation(); deleteSession(s.id); }}
                          className="opacity-0 group-hover:opacity-100 text-[10px] text-red-500 hover:text-red-700">
                          {t.common.delete}
                        </button>
                      </div>
                    </div>
                  ))}
                </div>
              </div>
              {sessionsOpen && (
                <div className="fixed inset-0 z-40 lg:hidden" onClick={() => setSessionsOpen(false)} />
              )}
            </div>
          </>
        )}

        <div className="flex-1 min-w-0">
          <div className="flex gap-2 mb-4 overflow-x-auto pb-1">
            {SCENES.map(s => (
              <button key={s.id} onClick={() => handleSceneChange(s.id)}
                className={`flex items-center gap-1.5 px-3 py-1.5 rounded-xl text-xs font-medium whitespace-nowrap border transition-colors shrink-0 ${
                  scene === s.id
                    ? 'bg-brand-600 text-white border-brand-600'
                    : 'bg-card text-muted-foreground border-border hover:border-brand-400 hover:text-foreground'
                }`}>
                <span>{s.icon}</span>
                <span>{s.name}</span>
              </button>
            ))}
          </div>

          <div className="flex items-center justify-between mb-2">
            <div />
            <button onClick={() => setShowParams(!showParams)}
              className={`flex items-center gap-1.5 px-3 py-1 text-xs font-medium rounded-lg border transition-colors ${
                showParams ? 'bg-accent text-foreground border-border' : 'text-muted-foreground border-border hover:text-foreground hover:bg-accent'
              }`}>
              <svg className={`w-3.5 h-3.5 transition-transform ${showParams ? 'rotate-180' : ''}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 6V4m0 2a2 2 0 100 4m0-4a2 2 0 110 4m-6 8a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4m6 6v10m6-2a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4" />
              </svg>
              {t.sandbox.advancedParams}
            </button>
          </div>

          {showParams && (
            <div className="bg-card border border-border rounded-xl p-4 mb-3 space-y-3">
              {[
                { label: t.sandbox.temperature, min: 0, max: 2, step: 0.1, val: temperature, set: setTemperature, fmt: (v: number) => v.toFixed(1) },
                { label: t.sandbox.topP, min: 0, max: 1, step: 0.05, val: topP, set: setTopP, fmt: (v: number) => v.toFixed(2) },
                { label: t.sandbox.maxTokens, min: 100, max: 8192, step: 100, val: maxTokens, set: setMaxTokens, fmt: (v: number) => String(v) },
              ].map(p => (
                <div key={p.label}>
                  <div className="flex items-center justify-between mb-1">
                    <label className="text-xs font-medium text-foreground">{p.label}</label>
                    <span className="text-xs text-muted-foreground tabular-nums">{p.fmt(p.val)}</span>
                  </div>
                  <input type="range" min={p.min} max={p.max} step={p.step} value={p.val}
                    onChange={e => p.set(parseFloat(e.target.value))}
                    className="w-full h-1.5 bg-muted rounded-full appearance-none cursor-pointer accent-brand-600" />
                </div>
              ))}
            </div>
          )}

          <div className="bg-card rounded-2xl border border-border shadow-sm overflow-hidden flex flex-col" style={{ maxHeight: '65vh' }}>
            <div ref={messagesContainerRef} className="flex-1 overflow-y-auto p-4 space-y-4">
              {isNewChat && (
                <div className="flex flex-wrap gap-2 mb-4">
                  {currentScene?.starters?.map((q, i) => (
                    <button key={i} onClick={() => setInput(q)}
                      className="px-3 py-1.5 text-xs bg-muted text-muted-foreground rounded-full border border-border hover:bg-accent hover:text-foreground transition-colors">
                      {q}
                    </button>
                  ))}
                </div>
              )}
              {messages.map((msg, i) => {
                if (msg.role === 'system') return null;
                const isLastAssistant = msg.role === 'assistant' && i === messages.length - 1;
                return (
                  <div key={i}>
                    <div className={`flex items-start gap-3 ${msg.role === 'user' ? 'justify-end' : ''}`}>
                      {msg.role === 'assistant' && (
                        <div className="w-8 h-8 bg-brand-600 rounded-xl flex items-center justify-center text-white text-sm font-bold shrink-0">Y</div>
                      )}
                      <div className={`max-w-[75%] rounded-2xl px-4 py-2.5 text-sm leading-relaxed whitespace-pre-wrap ${msg.role === 'user' ? 'bg-brand-600 text-white rounded-tr-none' : 'bg-muted text-foreground rounded-tl-none'}`}>
                        {(() => {
                          const parts = msg.content.split(/(```(?:\w+)?\n[\s\S]*?```)/g)
                          return parts.map((part, pi) => {
                            const match = part.match(/^```(\w*)\n([\s\S]*)```$/)
                            if (match) {
                              const [, lang, code] = match
                              return <CodeBlock key={pi} code={code.trim()} language={lang || undefined} />
                            }
                            if (pi > 0 && parts[pi-1].startsWith('```')) return null
                            return <span key={pi} className="whitespace-pre-wrap">{part}</span>
                          })
                        })()}
                      </div>
                      {msg.role === 'user' && (
                        <div className="w-8 h-8 bg-muted-foreground/20 rounded-xl flex items-center justify-center text-xs font-bold shrink-0">我</div>
                      )}
                    </div>
                    {msg.role === 'assistant' && currentSessionId && isLastAssistant && (
                      <div className="flex items-center gap-2 mt-1 ml-11">
                        <button onClick={() => handleFeedback(currentSessionId, 'LIKE')}
                          className={`text-xs px-2 py-1 rounded-full border transition-colors ${sessionFeedback[currentSessionId] === 'LIKE' ? 'bg-green-500/10 text-green-600 border-green-300' : 'text-muted-foreground border-border hover:border-green-300 hover:text-green-600'}`}>
                          {t.sandbox.helpful}
                        </button>
                        <button onClick={() => handleFeedback(currentSessionId, 'DISLIKE')}
                          className={`text-xs px-2 py-1 rounded-full border transition-colors ${sessionFeedback[currentSessionId] === 'DISLIKE' ? 'bg-red-500/10 text-red-600 border-red-300' : 'text-muted-foreground border-border hover:border-red-300 hover:text-red-600'}`}>
                          {t.sandbox.notHelpful}
                        </button>
                      </div>
                    )}
                    {msg.role === 'assistant' && extractCodeBlocks(msg.content).length > 0 && (
                      <div className="flex flex-wrap gap-2 mt-2 ml-11">
                        {extractCodeBlocks(msg.content).map((code, ci) => (
                          <button key={ci} onClick={() => window.open(`/sandbox/code?code=${btoa(code)}`, '_blank')}
                            className="text-xs px-2.5 py-1 rounded-full border border-border text-brand-600 hover:bg-accent transition-colors">
                            {t.sandbox.runInCodeSandbox}
                          </button>
                        ))}
                      </div>
                    )}
                  </div>
                );
              })}
              {sending && (
                <div className="flex items-start gap-3">
                  <div className="w-8 h-8 bg-brand-600 rounded-xl flex items-center justify-center text-white text-sm font-bold shrink-0">Y</div>
                  <div className="bg-muted rounded-2xl rounded-tl-none px-4 py-2.5">
                    <span className="inline-flex gap-1">
                      <span className="w-2 h-2 bg-muted-foreground/40 rounded-full animate-bounce" />
                      <span className="w-2 h-2 bg-muted-foreground/40 rounded-full animate-bounce" style={{ animationDelay: '150ms' }} />
                      <span className="w-2 h-2 bg-muted-foreground/40 rounded-full animate-bounce" style={{ animationDelay: '300ms' }} />
                    </span>
                  </div>
                </div>
              )}
              {!sending && messages.length > 2 && (
                <div className="flex justify-end gap-2">
                  <button onClick={shareSessionLink}
                    className="text-xs text-brand-600 hover:underline">
                    {t.sandbox.copyShareLink}
                  </button>
                  <button onClick={() => {
                    const lastAssistantMsg = [...messages].reverse().find(m => m.role === 'assistant');
                    if (lastAssistantMsg) shareToCommunity(lastAssistantMsg.content);
                  }} className="text-xs text-brand-600 hover:underline">
                    {t.sandbox.shareToCommunity}
                  </button>
                </div>
              )}
              <div ref={messagesEndRef} />
            </div>

            <div className="border-t border-border p-4">
              {quota && (
                <div className="text-xs text-muted-foreground mb-2">
                  {t.sandbox.dailyQuota.replace('{used}', String(quota.used)).replace('{remaining}', String(quota.remaining))}
                </div>
              )}
              {uploadedImages.length > 0 && (
                <div className="flex gap-2 mb-2 flex-wrap">
                  {uploadedImages.map((img, i) => (
                    <div key={i} className="relative group">
                      <img src={img} alt="" className="w-16 h-16 object-cover rounded-lg border border-border" />
                      <button onClick={() => setUploadedImages(prev => prev.filter((_, j) => j !== i))}
                        className="absolute -top-1.5 -right-1.5 w-5 h-5 bg-red-500 text-white rounded-full text-xs flex items-center justify-center opacity-0 group-hover:opacity-100 transition-opacity">×</button>
                    </div>
                  ))}
                </div>
              )}
              <form onSubmit={handleSend} className="flex gap-2">
                <input ref={fileInputRef} type="file" accept="image/*" className="hidden"
                  onChange={async e => {
                    const file = e.target.files?.[0]
                    if (!file) return
                    setUploading(true)
                    const formData = new FormData()
                    formData.append('file', file)
                    try {
                      const tk = getToken()
                      const res = await fetch(`${API_BASE}/upload`, {
                        method: 'POST',
                        headers: tk ? { Authorization: `Bearer ${tk}` } : {},
                        body: formData,
                      })
                      const data = await res.json()
                      if (data.url) setUploadedImages(prev => [...prev, data.url])
                    } catch {}
                    setUploading(false)
                  }} />
                <button type="button" onClick={() => fileInputRef.current?.click()} disabled={uploading || !isLoggedIn}
                  className="px-2.5 py-2.5 text-muted-foreground hover:text-foreground border border-input rounded-xl hover:bg-accent disabled:opacity-50">
                  <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
                  </svg>
                </button>
                <input type="text" value={input} onChange={e => setInput(e.target.value)}
                  placeholder={t.sandbox.placeholder} disabled={sending}
                  className="flex-1 px-4 py-2.5 bg-background border border-input rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-ring disabled:opacity-50" />
                <button type="submit" disabled={sending || (!input.trim() && uploadedImages.length === 0)}
                  className="px-5 py-2.5 bg-brand-600 text-white text-sm font-medium rounded-xl hover:bg-brand-700 disabled:opacity-50">
                  {sending ? t.sandbox.sending : t.sandbox.send}
                </button>
              </form>
            </div>
          </div>

          <div className="mt-4 text-center text-xs text-muted-foreground">
            {t.sandbox.aiReplyDisclaimer}{!isLoggedIn && ` ${t.sandbox.loginForMoreQuota}`}
          </div>
        </div>
      </div>
    </div>
  );
}