import React, { useState, useEffect } from 'react';
import { Activity, Clock, Folders, CheckCircle2, Loader2 } from 'lucide-react';
import { progressWS, type ProgressMessage } from '../lib/websocket';
import { cn } from '../lib/utils';

interface QueueTask {
  id: string;
  name: string;
  progress: number;
  status: string;
}

export function Dashboard() {
  const [tasks, setTasks] = useState<QueueTask[]>([
    { id: '1', name: 'City_Driving_Dataset_004.mp4', progress: 85, status: '正在截取帧 (30fps)' },
    { id: '2', name: 'Pedestrian_Night_Vision_02.mkv', progress: 32, status: '正在截取帧 (60fps)' },
    { id: '3', name: 'Drone_Mapping_Sector_7.avi', progress: 0, status: '队列排队等待中' },
  ]);
  const [isConnected, setIsConnected] = useState(false);
  const [activityLog, setActivityLog] = useState<Array<{ time: string; message: string; project?: string }>>([
    { time: '10 分钟前', message: '语义归档完成 54 帧', project: 'Highway_Data' },
    { time: '25 分钟前', message: '项目解析开始', project: 'City_Driving_Dataset_004' },
    { time: '1 小时前', message: '模板库更新: Cityscapes_v2', project: '系统' },
    { time: '2 小时前', message: 'AI 推理完成 12 个实例', project: 'Nav_Cam_Left' },
  ]);

  useEffect(() => {
    let mounted = true;
    const timer = setTimeout(() => {
      if (mounted) progressWS.connect();
    }, 500);

    const unsubscribe = progressWS.onProgress((data: ProgressMessage) => {
      if (!mounted) return;
      setIsConnected(progressWS.isConnected());

      if (data.type === 'progress' && data.taskId && data.filename) {
        setTasks((prev) => {
          const exists = prev.find((t) => t.id === data.taskId);
          if (exists) {
            return prev.map((t) =>
              t.id === data.taskId
                ? { ...t, progress: data.progress ?? t.progress, status: data.status ?? t.status }
                : t
            );
          }
          return [
            ...prev,
            {
              id: data.taskId!,
              name: data.filename!,
              progress: data.progress ?? 0,
              status: data.status ?? '处理中',
            },
          ];
        });
      }

      if (data.type === 'complete' && data.taskId) {
        setTasks((prev) =>
          prev.map((t) =>
            t.id === data.taskId ? { ...t, progress: 100, status: '已完成' } : t
          )
        );
        setActivityLog((prev) => [
          { time: '刚刚', message: `解析完成: ${data.filename || data.taskId}`, project: '系统' },
          ...prev.slice(0, 9),
        ]);
      }

      if (data.type === 'error' && data.taskId) {
        setTasks((prev) =>
          prev.map((t) =>
            t.id === data.taskId ? { ...t, status: `错误: ${data.message || '未知错误'}` } : t
          )
        );
      }

      if (data.type === 'status') {
        setActivityLog((prev) => [
          { time: '刚刚', message: data.message || '状态更新', project: '系统' },
          ...prev.slice(0, 9),
        ]);
      }
    });

    const checkConnection = setInterval(() => {
      if (mounted) setIsConnected(progressWS.isConnected());
    }, 5000);

    return () => {
      mounted = false;
      unsubscribe();
      clearInterval(checkConnection);
      progressWS.disconnect();
    };
  }, []);

  const stats = [
    { label: '运行中项目', value: '14', icon: Folders, color: 'text-blue-400', bg: 'bg-blue-400/10' },
    { label: '排队处理任务', value: tasks.length.toString(), icon: Clock, color: 'text-orange-400', bg: 'bg-orange-400/10' },
    { label: '已归档批次', value: '128', icon: CheckCircle2, color: 'text-emerald-400', bg: 'bg-emerald-400/10' },
    { label: '系统负载', value: '78%', icon: Activity, color: 'text-cyan-400', bg: 'bg-cyan-400/10' },
  ];

  return (
    <div className="p-8 w-full h-full overflow-y-auto bg-[#0a0a0a]">
      <header className="mb-8">
        <div className="flex items-center gap-3">
          <h1 className="text-3xl font-medium tracking-tight text-white">系统整体概况</h1>
          <div className={cn(
            "flex items-center gap-1.5 text-[10px] uppercase font-mono px-2 py-1 rounded border",
            isConnected 
              ? "bg-emerald-500/10 text-emerald-400 border-emerald-500/20"
              : "bg-amber-500/10 text-amber-400 border-amber-500/20"
          )}>
            <div className={cn("w-1.5 h-1.5 rounded-full", isConnected ? "bg-emerald-500" : "bg-amber-500 animate-pulse")} />
            {isConnected ? 'WebSocket 已连接' : 'WebSocket 断开'}
          </div>
        </div>
        <p className="text-gray-400 text-sm mt-1">系统全局数据吞吐状态与所有接入项目进度实时洞察驾驶舱。</p>
      </header>

      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-4 mb-8">
        {stats.map((stat, i) => {
          const Icon = stat.icon;
          return (
            <div key={i} className="bg-[#111] border border-white/5 p-5 rounded-xl block transition-all hover:border-white/20">
              <div className="flex items-center gap-4 mb-4">
                <div className={`w-10 h-10 rounded-lg flex items-center justify-center ${stat.bg} ${stat.color}`}>
                  <Icon size={20} />
                </div>
                <div className="text-xl font-mono text-gray-100">{stat.value}</div>
              </div>
              <div className="text-sm font-medium text-gray-500 uppercase tracking-widest">{stat.label}</div>
            </div>
          );
        })}
      </div>

      <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
        <div className="lg:col-span-2 bg-[#111] border border-white/5 rounded-xl p-6 min-h-[400px]">
           <h2 className="text-sm font-medium text-gray-400 uppercase tracking-widest mb-6">解析队列 (FFmpeg 挂起任务)</h2>
           <div className="space-y-4">
              {tasks.map((task) => (
                <div key={task.id} className="bg-[#0d0d0d] border border-white/5 p-4 rounded-lg">
                  <div className="flex justify-between items-center mb-2">
                    <span className="font-mono text-sm text-gray-200">{task.name}</span>
                    <span className="text-xs text-cyan-400 font-mono">{task.progress}%</span>
                  </div>
                  <div className="w-full h-1.5 bg-white/5 rounded-full overflow-hidden mb-2">
                    <div className="h-full bg-gradient-to-r from-cyan-600 to-cyan-400 rounded-full transition-all duration-500" style={{ width: `${task.progress}%` }} />
                  </div>
                  <div className="text-xs text-gray-500 flex items-center gap-2">
                    {task.status === '已完成' ? (
                      <CheckCircle2 size={12} className="text-emerald-400" />
                    ) : task.status.includes('错误') ? (
                      <span className="text-red-400">●</span>
                    ) : (
                      <Loader2 size={12} className="text-cyan-400 animate-spin" />
                    )}
                    {task.status}
                  </div>
                </div>
              ))}
              {tasks.length === 0 && (
                <div className="text-sm text-gray-500 text-center py-12">当前无处理任务</div>
              )}
           </div>
        </div>

        <div className="bg-[#111] border border-white/5 rounded-xl p-6 min-h-[400px]">
           <h2 className="text-sm font-medium text-gray-400 uppercase tracking-widest mb-6">近期实时流转记录</h2>
           <div className="space-y-6 relative before:absolute before:inset-0 before:ml-[11px] before:-translate-x-px md:before:mx-auto md:before:translate-x-0 before:h-full before:w-0.5 before:bg-gradient-to-b before:from-transparent before:via-white/10 before:to-transparent">
              {activityLog.map((log, i) => (
                <div key={i} className="relative flex items-center justify-between md:justify-normal md:odd:flex-row-reverse group is-active">
                  <div className="flex items-center justify-center w-6 h-6 rounded-full border border-white/10 bg-[#111] group-[.is-active]:bg-cyan-500 group-[.is-active]:border-cyan-400 text-slate-500 group-[.is-active]:text-black shadow shrink-0 md:order-1 md:group-odd:-translate-x-1/2 md:group-even:translate-x-1/2 z-10" />
                  <div className="w-[calc(100%-4rem)] md:w-[calc(50%-2.5rem)] bg-[#0d0d0d] p-3 rounded border border-white/5">
                    <div className="text-xs text-gray-400 mb-1">{log.time}</div>
                    <div className="text-sm font-medium text-gray-200">{log.message}</div>
                    <div className="text-xs text-gray-500">归属项目: {log.project}</div>
                  </div>
                </div>
              ))}
           </div>
        </div>
      </div>
    </div>
  );
}
