import { useEffect } from 'react';
import { useConnectionStore } from '../store/connectionStore';
import { useConfigStore } from '../store/configStore';
import { Clock, RefreshCw, Play, Pause, AlertCircle, CheckCircle2 } from 'lucide-react';

const STATUS_CONFIG: Record<string, { icon: typeof Play; color: string; label: string }> = {
  active: { icon: Play, color: 'text-green-500', label: '运行中' },
  paused: { icon: Pause, color: 'text-yellow-500', label: '已暂停' },
  completed: { icon: CheckCircle2, color: 'text-blue-500', label: '已完成' },
  error: { icon: AlertCircle, color: 'text-red-500', label: '错误' },
};

export function TaskList() {
  const scheduledTasks = useConfigStore((s) => s.scheduledTasks);
  const connectionState = useConnectionStore((s) => s.connectionState);
  const loadScheduledTasks = useConfigStore((s) => s.loadScheduledTasks);

  const connected = connectionState === 'connected';

  useEffect(() => {
    if (connected) {
      loadScheduledTasks();
    }
  }, [connected]);

  if (!connected) {
    return (
      <div className="flex flex-col items-center justify-center h-full text-gray-400 text-xs px-4 text-center">
        <Clock className="w-8 h-8 mb-2 opacity-30" />
        <p>定时任务</p>
        <p className="mt-1">连接 Gateway 后可用</p>
      </div>
    );
  }

  return (
    <div className="h-full flex flex-col">
      {/* Header */}
      <div className="flex items-center justify-between px-3 py-2 border-b border-gray-200">
        <span className="text-xs font-medium text-gray-500">Heartbeat 任务</span>
        <button
          onClick={loadScheduledTasks}
          className="p-1 text-gray-400 hover:text-orange-500 rounded"
          title="刷新"
        >
          <RefreshCw className="w-3.5 h-3.5" />
        </button>
      </div>

      <div className="flex-1 overflow-y-auto custom-scrollbar">
        {scheduledTasks.length > 0 ? (
          scheduledTasks.map((task) => {
            const cfg = STATUS_CONFIG[task.status] || STATUS_CONFIG.active;
            const StatusIcon = cfg.icon;

            return (
              <div
                key={task.id}
                className="px-3 py-3 border-b border-gray-50 hover:bg-gray-50"
              >
                <div className="flex items-center gap-2 mb-1">
                  <StatusIcon className={`w-3.5 h-3.5 flex-shrink-0 ${cfg.color}`} />
                  <span className="text-xs font-medium text-gray-900 truncate">{task.name}</span>
                </div>
                <div className="pl-5.5 space-y-0.5">
                  <div className="text-[11px] text-gray-500 font-mono">{task.schedule}</div>
                  {task.description && (
                    <div className="text-[11px] text-gray-400 truncate">{task.description}</div>
                  )}
                  <div className="flex gap-3 text-[10px] text-gray-400">
                    {task.lastRun && <span>上次: {formatTaskTime(task.lastRun)}</span>}
                    {task.nextRun && <span>下次: {formatTaskTime(task.nextRun)}</span>}
                  </div>
                </div>
              </div>
            );
          })
        ) : (
          <div className="flex flex-col items-center justify-center h-full text-gray-400 text-xs px-4 text-center">
            <Clock className="w-8 h-8 mb-2 opacity-30" />
            <p>暂无定时任务</p>
            <p className="mt-1">Heartbeat 引擎管理的定时任务</p>
            <p className="mt-0.5 text-[11px]">默认心跳周期: 1h</p>
          </div>
        )}
      </div>
    </div>
  );
}

function formatTaskTime(timeStr: string): string {
  try {
    const d = new Date(timeStr);
    const now = new Date();
    const diffMs = now.getTime() - d.getTime();
    const future = diffMs < 0;
    const absDiff = Math.abs(diffMs);
    const mins = Math.floor(absDiff / 60000);

    if (mins < 1) return future ? '即将' : '刚刚';
    if (mins < 60) return future ? `${mins}分钟后` : `${mins}分钟前`;

    const hrs = Math.floor(mins / 60);
    if (hrs < 24) return future ? `${hrs}小时后` : `${hrs}小时前`;

    return `${d.getMonth() + 1}/${d.getDate()} ${d.getHours().toString().padStart(2, '0')}:${d.getMinutes().toString().padStart(2, '0')}`;
  } catch {
    return timeStr;
  }
}
