import { useState, useEffect, useRef, useCallback } from 'react';
import type { ComponentType } from 'react';
import { toast } from 'sonner';
import { agentApi } from '@/api';
import { AgentWizard } from './AgentWizard';
import { HostDetailDialog } from './HostDetailDialog';
import { isOnline, timeAgo, asList } from './agentUtils';
import type { AgentHostRecord } from '@/types';
import { Card, CardContent } from '@/components/ui/card';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Textarea } from '@/components/ui/textarea';
import { Badge } from '@/components/ui/badge';
import { Progress } from '@/components/ui/progress';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from '@/components/ui/dialog';

import {
  Cpu,
  MemoryStick,
  HardDrive,
  Wifi,
  WifiOff,
  RefreshCw,
  Terminal,
  Rocket,
  Activity,
  Network,
  Loader2,
  Clock,
  Server,
} from 'lucide-react';

// ============ 组件 ============

export function AgentMonitor() {
  const [hosts, setHosts] = useState<AgentHostRecord[]>([]);
  const [loading, setLoading] = useState(true);
  const [refreshing, setRefreshing] = useState(false);
  const [selectedHost, setSelectedHost] = useState<AgentHostRecord | null>(null);
  const [wizardOpen, setWizardOpen] = useState(false);
  const timerRef = useRef<ReturnType<typeof setInterval> | null>(null);

  // 远程命令
  const [cmdOpen, setCmdOpen] = useState(false);
  const [cmdHost, setCmdHost] = useState('');
  const [cmdCommand, setCmdCommand] = useState('');
  const [cmdTimeout, setCmdTimeout] = useState(30);
  const [cmdSubmitting, setCmdSubmitting] = useState(false);
  const [cmdResult, setCmdResult] = useState<{ status: string; result?: string; output?: string; error?: string } | null>(null);

  const loadLatest = useCallback(async (silent = false) => {
    if (!silent) setRefreshing(true);
    try {
      const data = await agentApi.getLatest();
      const list = asList(data) as AgentHostRecord[];
      setHosts(list);
      // 同步选中主机的最新数据
      if (selectedHost) {
        const fresh = list.find((h) => h.hostname === selectedHost.hostname);
        if (fresh) setSelectedHost(fresh);
      }
    } catch (err) {
      if (!silent) toast.error('加载主机列表失败');
      console.error(err);
    } finally {
      setLoading(false);
      setRefreshing(false);
    }
  }, [selectedHost]);

  useEffect(() => {
    loadLatest();
    timerRef.current = setInterval(() => loadLatest(true), 30000);
    return () => {
      if (timerRef.current) clearInterval(timerRef.current);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  // 打开远程命令弹窗
  const openCommandDialog = (hostname: string) => {
    setCmdHost(hostname);
    setCmdCommand('');
    setCmdTimeout(30);
    setCmdResult(null);
    setCmdOpen(true);
  };

  // 提交远程命令（直连 SSH 即时返回）
  const submitCommand = async () => {
    if (!cmdCommand.trim()) {
      toast.error('请输入要执行的命令');
      return;
    }
    setCmdSubmitting(true);
    setCmdResult(null);
    try {
      const res = await agentApi.execCommand({
        hostname: cmdHost,
        command: cmdCommand.trim(),
        timeout: Number(cmdTimeout) || 30,
      }) as Record<string, unknown>;
      const resData = (res?.data ?? {}) as Record<string, unknown>;
      setCmdResult({
        status: res?.code === 200 ? 'completed' : 'failed',
        result: (resData.output as string) || (res?.message as string) || '无输出',
        error: resData.error as string | undefined,
      });
    } catch (err) {
      setCmdResult({ status: 'failed', result: err?.message || '执行失败' });
    } finally {
      setCmdSubmitting(false);
      loadLatest(true);
    }
  };

  const closeCommandDialog = () => {
    setCmdOpen(false);
  };

  const onlineCount = hosts.filter((h) => isOnline(h.last_report || h.last_reported_at || h.updated_at)).length;

  const stats = [
    { label: '主机总数', value: hosts.length, icon: Server, color: 'dg-text-blue' },
    { label: '在线', value: onlineCount, icon: Wifi, color: 'dg-text-green' },
    { label: '离线', value: hosts.length - onlineCount, icon: WifiOff, color: 'dg-text-red' },
  ];

  return (
    <div className="space-y-4">
      {/* 页头 */}
      <div className="flex items-center justify-between">
        <div>
          <h2 className="text-xl font-semibold text-[var(--dg-text-primary)]">Agent 监控</h2>
          <p className="text-sm dg-text-secondary mt-0.5">实时监控 Agent 上报的主机指标</p>
        </div>
        <div className="flex items-center gap-2">
          <Button
            variant="outline"
            size="sm"
            onClick={() => loadLatest()}
            disabled={refreshing}
            className="dg-input text-[var(--dg-text-secondary)] hover:bg-[var(--dg-bg-hover)] hover:text-[var(--dg-text-primary)]"
          >
            <RefreshCw className={`h-4 w-4 mr-1.5 ${refreshing ? 'animate-spin' : ''}`} />
            刷新
          </Button>
          <Button
            size="sm"
            onClick={() => setWizardOpen(true)}
            className="bg-blue-600 hover:bg-blue-700 text-white"
          >
            <Rocket className="h-4 w-4 mr-1.5" />
            部署Agent
          </Button>
        </div>
      </div>

      {/* 统计卡片 */}
      <div className="grid grid-cols-3 gap-3">
        {stats.map((s) => (
          <Card key={s.label} className="dg-card py-4">
            <CardContent className="flex items-center gap-3">
              <div className="w-10 h-10 rounded-lg bg-[var(--dg-bg-tertiary)] flex items-center justify-center">
                <s.icon className={`h-5 w-5 ${s.color}`} />
              </div>
              <div>
                <div className="text-2xl font-bold text-[var(--dg-text-primary)]">{s.value}</div>
                <div className="text-xs dg-text-secondary">{s.label}</div>
              </div>
            </CardContent>
          </Card>
        ))}
      </div>

      {/* 主机列表 */}
      {loading ? (
        <Card className="dg-card">
          <CardContent className="flex items-center justify-center py-16">
            <Loader2 className="h-6 w-6 animate-spin dg-text-muted" />
            <span className="ml-2 dg-text-secondary">加载中...</span>
          </CardContent>
        </Card>
      ) : hosts.length === 0 ? (
        <Card className="dg-card">
          <CardContent className="flex flex-col items-center justify-center py-16">
            <Server className="h-10 w-10 dg-text-muted mb-3" />
            <p className="dg-text-secondary">暂无 Agent 上报数据</p>
            <Button
              size="sm"
              onClick={() => setWizardOpen(true)}
              className="mt-4 bg-blue-600 hover:bg-blue-700 text-white"
            >
              <Rocket className="h-4 w-4 mr-1.5" />
              立即部署
            </Button>
          </CardContent>
        </Card>
      ) : (
        <div className="grid grid-cols-1 md:grid-cols-2 xl:grid-cols-3 gap-3">
          {hosts.map((host) => {
            const online = isOnline(host.last_report || host.last_reported_at || host.updated_at);
            const cpu = Number(host.cpu_percent ?? host.cpu ?? 0);
            const mem = Number(host.mem_percent ?? host.mem ?? 0);
            const disk = Number(host.disk_percent ?? host.disk ?? 0);
            const ports: Record<string, unknown>[] = Array.isArray(host.ports) ? (host.ports as Record<string, unknown>[]) : [];
            return (
              <Card
                key={host.hostname}
                className="dg-card hover:border-[var(--dg-border)] transition-colors cursor-pointer py-4"
                onClick={() => setSelectedHost(host)}
              >
                <CardContent className="space-y-3">
                  <div className="flex items-center justify-between">
                    <div className="flex items-center gap-2 min-w-0">
                      <Server className="h-4 w-4 dg-text-muted shrink-0" />
                      <span className="font-medium text-[var(--dg-text-primary)] truncate">{host.hostname}</span>
                    </div>
                    {online ? (
                      <Badge className="bg-emerald-500/15 dg-text-green border border-emerald-500/30">
                        <Wifi className="h-3 w-3 mr-1" />
                        在线
                      </Badge>
                    ) : (
                      <Badge className="bg-red-500/15 dg-text-red border border-red-500/30">
                        <WifiOff className="h-3 w-3 mr-1" />
                        离线
                      </Badge>
                    )}
                  </div>

                  {/* 指标条 */}
                  <div className="space-y-2">
                    <MetricBar icon={Cpu} label="CPU" value={cpu} />
                    <MetricBar icon={MemoryStick} label="内存" value={mem} />
                    <MetricBar icon={HardDrive} label="磁盘" value={disk} />
                  </div>

                  {/* 端口 & 时间 */}
                  <div className="flex items-center justify-between text-xs dg-text-secondary">
                    <span className="inline-flex items-center gap-1">
                      <Network className="h-3.5 w-3.5" />
                      {ports.length} 个端口
                    </span>
                    <span className="inline-flex items-center gap-1">
                      <Clock className="h-3.5 w-3.5" />
                      {timeAgo(host.last_report || host.last_reported_at || host.updated_at)}
                    </span>
                  </div>

                  {/* 操作 */}
                  <div className="flex gap-2 pt-1" onClick={(e) => e.stopPropagation()}>
                    <Button
                      size="sm"
                      variant="outline"
                      className="flex-1 h-8 dg-input text-[var(--dg-text-secondary)] hover:bg-[var(--dg-bg-hover)]"
                      onClick={() => openCommandDialog(host.hostname)}
                    >
                      <Terminal className="h-3.5 w-3.5 mr-1" />
                      远程命令
                    </Button>
                    <Button
                      size="sm"
                      variant="outline"
                      className="flex-1 h-8 dg-input text-[var(--dg-text-secondary)] hover:bg-[var(--dg-bg-hover)]"
                      onClick={() => setSelectedHost(host)}
                    >
                      <Activity className="h-3.5 w-3.5 mr-1" />
                      详情
                    </Button>
                  </div>
                </CardContent>
              </Card>
            );
          })}
        </div>
      )}

      {/* 详情抽屉 */}
      <HostDetailDialog
        host={selectedHost}
        onClose={() => setSelectedHost(null)}
        onCommand={(hn) => openCommandDialog(hn)}
      />

      {/* 远程命令弹窗 */}
      <Dialog open={cmdOpen} onOpenChange={(v) => { if (!v) closeCommandDialog(); }}>
        <DialogContent className="max-w-2xl dg-card text-[var(--dg-text-primary)]">
          <DialogHeader>
            <DialogTitle className="text-[var(--dg-text-primary)] flex items-center gap-2">
              <Terminal className="h-5 w-5 dg-text-blue" />
              远程命令
            </DialogTitle>
            <DialogDescription className="dg-text-secondary">
              在 {cmdHost} 上执行命令
            </DialogDescription>
          </DialogHeader>

          <div className="space-y-3">
            <div className="grid grid-cols-2 gap-3">
              <div className="space-y-1.5">
                <Label className="text-[var(--dg-text-secondary)] text-xs">目标主机</Label>
                <Input
                  value={cmdHost}
                  onChange={(e) => setCmdHost(e.target.value)}
                  readOnly
                  className="h-9 dg-input"
                />
              </div>
            </div>

            <div className="space-y-1.5">
              <Label className="text-[var(--dg-text-secondary)] text-xs">命令</Label>
              <Textarea
                value={cmdCommand}
                onChange={(e) => setCmdCommand(e.target.value)}
                placeholder="例如：free -m && df -h"
                rows={3}
                className="bg-[var(--dg-bg-primary)] border-[var(--dg-border)] text-[var(--dg-text-primary)] font-mono text-sm resize-none"
              />
            </div>

            <div className="w-40 space-y-1.5">
              <Label className="text-[var(--dg-text-secondary)] text-xs">超时(秒)</Label>
              <Input
                type="number"
                value={cmdTimeout}
                onChange={(e) => setCmdTimeout(Number(e.target.value) || 30)}
                className="h-9 dg-input"
              />
            </div>

            {/* 结果展示 */}
            {cmdResult && (
              <div className="space-y-1.5">
                <div className="flex items-center gap-2">
                  <Label className="text-[var(--dg-text-secondary)] text-xs">执行结果</Label>
                  <Badge
                    className={
                      cmdResult.status === 'success' || cmdResult.status === 'done' || cmdResult.status === 'completed'
                        ? 'bg-emerald-500/15 dg-text-green border border-emerald-500/30'
                        : cmdResult.status === 'timeout'
                        ? 'bg-amber-500/15 dg-text-yellow border border-amber-500/30'
                        : 'bg-red-500/15 dg-text-red border border-red-500/30'
                    }
                  >
                    {cmdResult.status}
                  </Badge>
                </div>
                <pre className="text-xs text-[var(--dg-text-secondary)] font-mono whitespace-pre-wrap break-all bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded-lg p-3 max-h-48 overflow-auto">
                  {cmdResult.result || cmdResult.output || cmdResult.error || '无输出'}
                </pre>
              </div>
            )}
          </div>

          <DialogFooter className="gap-2">
            <Button variant="outline" onClick={closeCommandDialog} className="border-[var(--dg-border)] text-[var(--dg-text-secondary)]">
              关闭
            </Button>
            <Button
              onClick={submitCommand}
              disabled={cmdSubmitting || !cmdCommand.trim()}
              className="bg-blue-600 hover:bg-blue-700 text-white"
            >
              {cmdSubmitting ? (
                <><Loader2 className="h-4 w-4 mr-1.5 animate-spin" />执行中</>
              ) : (
                <><Terminal className="h-4 w-4 mr-1.5" />执行</>
              )}
            </Button>
          </DialogFooter>
        </DialogContent>
      </Dialog>

      {/* 部署向导 */}
      <AgentWizard open={wizardOpen} onOpenChange={setWizardOpen} />
    </div>
  );
}

// ============ 指标条子组件 ============
function MetricBar({ icon: Icon, label, value }: { icon: ComponentType<{ className?: string }>; label: string; value: number }) {
  return (
    <div className="flex items-center gap-2">
      <Icon className="h-3.5 w-3.5 dg-text-muted shrink-0" />
      <span className="text-xs dg-text-secondary w-8 shrink-0">{label}</span>
      <div className="flex-1">
        <Progress value={value} className={`h-1.5 ${value >= 90 ? '[&>[data-slot=progress-indicator]]:bg-red-500' : value >= 75 ? '[&>[data-slot=progress-indicator]]:bg-amber-500' : '[&>[data-slot=progress-indicator]]:bg-emerald-500'}`} />
      </div>
      <span className={`text-xs font-medium w-10 text-right ${value >= 90 ? 'dg-text-red' : value >= 75 ? 'dg-text-yellow' : 'text-[var(--dg-text-secondary)]'}`}>
        {value.toFixed(1)}%
      </span>
    </div>
  );
}

export default AgentMonitor;