import { useState, useEffect, useCallback } from 'react';
import { Card, CardContent } from '@/components/ui/card';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Badge } from '@/components/ui/badge';
import {
  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
} from '@/components/ui/select';
import {
  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
} from '@/components/ui/table';
import { RefreshCw, Search, Server, Loader2 } from 'lucide-react';
import { kubernetesApi } from '@/api';
import type { JsonData } from '@/types/common';

export function KubernetesNodes() {
  const [clusters, setClusters] = useState<JsonData[]>([]);
  const [selectedCluster, setSelectedCluster] = useState('');
  const [nodes, setNodes] = useState<JsonData[]>([]);
  const [loading, setLoading] = useState(false);
  const [search, setSearch] = useState('');
  const [roleFilter, setRoleFilter] = useState('all');

  const loadClusters = useCallback(async () => {
    try {
      const res: JsonData = await kubernetesApi.getClusters();
      const list = res?.list || [];
      setClusters(list);
      if (list.length > 0 && !selectedCluster) setSelectedCluster(String(list[0].id));
    } catch { setClusters([]); }
  }, []);

  useEffect(() => { loadClusters(); }, [loadClusters]);

  const loadNodes = useCallback(async () => {
    if (!selectedCluster) return;
    setLoading(true);
    try {
      const res: JsonData = await kubernetesApi.getNodes(selectedCluster);
      setNodes(Array.isArray(res) ? res : (res?.list || []));
    } catch { setNodes([]); } finally { setLoading(false); }
  }, [selectedCluster]);

  useEffect(() => { loadNodes(); }, [loadNodes]);

  const filtered = nodes.filter((n) =>
    (n.name || '').toLowerCase().includes(search.toLowerCase()) &&
    (roleFilter === 'all' || n.role === roleFilter),
  );

  const getRoleBadge = (role: string) =>
    role === 'master'
      ? <Badge className="bg-blue-500/20 text-blue-400 border-blue-500/30">Master</Badge>
      : <Badge className="bg-emerald-500/20 text-emerald-400 border-emerald-500/30">Worker</Badge>;

  const getStatusBadge = (status: string) =>
    status === 'Ready'
      ? <Badge className="bg-emerald-500/20 text-emerald-400 border-emerald-500/30">{status}</Badge>
      : <Badge variant="destructive">{status || 'Unknown'}</Badge>;

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-slate-100">节点管理</h1>
          <p className="text-sm text-slate-500 mt-1">Kubernetes 集群工作节点状态与资源</p>
        </div>
        <div className="flex items-center gap-2">
          <Select value={selectedCluster} onValueChange={setSelectedCluster}>
            <SelectTrigger className="w-48 h-9 bg-slate-800/50 border-slate-700 text-slate-200">
              <SelectValue placeholder="选择集群" />
            </SelectTrigger>
            <SelectContent className="bg-slate-800 border-slate-700">
              {clusters.map((c) => (
                <SelectItem key={c.id} value={String(c.id)}>{c.name}</SelectItem>
              ))}
            </SelectContent>
          </Select>
          <Button variant="outline" size="icon" className="h-9 w-9 border-slate-700 text-slate-400" onClick={loadNodes} disabled={loading}>
            {loading ? <Loader2 className="h-4 w-4 animate-spin" /> : <RefreshCw className="h-4 w-4" />}
          </Button>
        </div>
      </div>

      <div className="flex items-center gap-3">
        <div className="relative w-56">
          <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-slate-500" />
          <Input placeholder="搜索节点..." value={search} onChange={(e) => setSearch(e.target.value)} className="pl-9 h-9 bg-slate-800/50 border-slate-700 text-slate-200" />
        </div>
        <Select value={roleFilter} onValueChange={setRoleFilter}>
          <SelectTrigger className="w-32 h-9 bg-slate-800/50 border-slate-700 text-slate-200">
            <SelectValue />
          </SelectTrigger>
          <SelectContent className="bg-slate-800 border-slate-700">
            <SelectItem value="all">全部角色</SelectItem>
            <SelectItem value="master">Master</SelectItem>
            <SelectItem value="worker">Worker</SelectItem>
          </SelectContent>
        </Select>
      </div>

      <Card className="bg-slate-900 border-slate-800">
        <CardContent className="p-0">
          <Table>
            <TableHeader>
              <TableRow className="border-slate-800 hover:bg-transparent">
                <TableHead className="text-slate-400">节点名称</TableHead>
                <TableHead className="text-slate-400">IP</TableHead>
                <TableHead className="text-slate-400">角色</TableHead>
                <TableHead className="text-slate-400">状态</TableHead>
                <TableHead className="text-slate-400">配置</TableHead>
                <TableHead className="text-slate-400">使用率</TableHead>
                <TableHead className="text-slate-400">Pods</TableHead>
                <TableHead className="text-slate-400">Kubelet</TableHead>
              </TableRow>
            </TableHeader>
            <TableBody>
              {loading ? (
                <TableRow><TableCell colSpan={8} className="text-center text-slate-500 py-12"><Loader2 className="h-5 w-5 animate-spin mx-auto mb-2" />加载中...</TableCell></TableRow>
              ) : filtered.length === 0 ? (
                <TableRow><TableCell colSpan={8} className="text-center text-slate-500 py-12"><Server className="h-8 w-8 mx-auto mb-2 opacity-50" />{selectedCluster ? '暂无节点数据' : '请选择集群'}</TableCell></TableRow>
              ) : (
                filtered.map((n) => (
                  <TableRow key={n.id} className="border-slate-800 hover:bg-slate-800/30">
                    <TableCell className="font-medium text-slate-200">{n.name}</TableCell>
                    <TableCell><code className="text-sm text-slate-300 bg-slate-800 px-1.5 py-0.5 rounded">{n.ip || '-'}</code></TableCell>
                    <TableCell>{getRoleBadge(n.role)}</TableCell>
                    <TableCell>{getStatusBadge(n.status)}</TableCell>
                    <TableCell className="text-sm text-slate-400">
                      {n.cpu ? `${n.cpu}核` : '-'} / {n.memory ? `${Math.round(n.memory / 1024)}GB` : '-'}
                    </TableCell>
                    <TableCell>
                      {(() => {
                        const cpu = n.cpu_usage || 0;
                        const mem = n.memory_usage || 0;
                        const bar = (val: number) => val >= 85 ? 'bg-red-500' : val >= 60 ? 'bg-yellow-500' : 'bg-emerald-500';
                        const txt = (val: number) => val >= 85 ? 'text-red-400' : val >= 60 ? 'text-yellow-400' : 'text-emerald-400';
                        return (
                          <div className="flex flex-col gap-1 min-w-[120px]">
                            <div className="flex items-center gap-2">
                              <span className="text-xs text-slate-500 w-7">CPU</span>
                              <div className="flex-1 h-1.5 rounded-full bg-slate-700/50 overflow-hidden">
                                <div className={`h-full rounded-full ${bar(cpu)}`} style={{ width: `${Math.min(cpu, 100)}%` }} />
                              </div>
                              <span className={`text-xs w-9 text-right ${txt(cpu)}`}>{cpu.toFixed(0)}%</span>
                            </div>
                            <div className="flex items-center gap-2">
                              <span className="text-xs text-slate-500 w-7">Mem</span>
                              <div className="flex-1 h-1.5 rounded-full bg-slate-700/50 overflow-hidden">
                                <div className={`h-full rounded-full ${bar(mem)}`} style={{ width: `${Math.min(mem, 100)}%` }} />
                              </div>
                              <span className={`text-xs w-9 text-right ${txt(mem)}`}>{mem.toFixed(0)}%</span>
                            </div>
                          </div>
                        );
                      })()}
                    </TableCell>
                    <TableCell className="text-sm text-slate-400">{n.pod_count || 0} / {n.max_pods || '-'}</TableCell>
                    <TableCell className="text-xs text-slate-500">{n.kubelet_version || '-'}</TableCell>
                  </TableRow>
                ))
              )}
            </TableBody>
          </Table>
        </CardContent>
      </Card>
    </div>
  );
}