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 { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
import {
  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
} from '@/components/ui/select';
import {
  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
} from '@/components/ui/table';
import {
  RefreshCw, Search, Boxes, Loader2, Container,
  Plus, Minus, RotateCw, Upload, FileText, Eye,
} from 'lucide-react';
import { kubernetesApi } from '@/services/api';
import { useToast } from '@/hooks/use-toast';
import { DeploymentDetail } from './DeploymentDetail';

export function KubernetesWorkloads() {
  const { toast } = useToast();
  const [clusters, setClusters] = useState<any[]>([]);
  const [selectedCluster, setSelectedCluster] = useState('');
  const [namespaces, setNamespaces] = useState<string[]>([]);
  const [selectedNamespace, setSelectedNamespace] = useState('all');
  const [deployments, setDeployments] = useState<any[]>([]);
  const [pods, setPods] = useState<any[]>([]);
  const [loading, setLoading] = useState(false);
  const [search, setSearch] = useState('');
  const [activeTab, setActiveTab] = useState('deployments');
  const [actionLoading, setActionLoading] = useState<Record<string, string>>({});

  // Detail view
  const [selectedDeployment, setSelectedDeployment] = useState<{ name: string; namespace: string } | null>(null);

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

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

  // Load namespaces when cluster changes
  const loadNamespaces = useCallback(async () => {
    if (!selectedCluster) return;
    try {
      const res: any = await kubernetesApi.getNamespaces(selectedCluster);
      const nsList: string[] = Array.isArray(res) ? res : (res?.list || res?.data || []);
      setNamespaces(nsList);
    } catch { setNamespaces([]); }
  }, [selectedCluster]);

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

  const loadData = useCallback(async () => {
    if (!selectedCluster) return;
    setLoading(true);
    const clusterCode = selectedCluster;
    try {
      if (selectedNamespace !== 'all') {
        const [depRes, podRes] = await Promise.all([
          kubernetesApi.getNamespaceDeployments(clusterCode, selectedNamespace).catch(() => []),
          kubernetesApi.getNamespacePods(clusterCode, selectedNamespace).catch(() => []),
        ]);
        const toArray = (v: any) => (Array.isArray(v) ? v : (v?.list || []));
        setDeployments(toArray(depRes));
        setPods(toArray(podRes));
      } else {
        const [depRes, podRes] = await Promise.all([
          kubernetesApi.getAllDeployments(clusterCode).catch(() => []),
          kubernetesApi.getAllPods(clusterCode).catch(() => []),
        ]);
        const toArray = (v: any) => (Array.isArray(v) ? v : (v?.list || []));
        setDeployments(toArray(depRes));
        setPods(toArray(podRes));
      }
    } catch { setDeployments([]); setPods([]); } finally { setLoading(false); }
  }, [selectedCluster, selectedNamespace]);

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

  const filteredDeps = deployments.filter((d) =>
    (d.name || '').toLowerCase().includes(search.toLowerCase()) &&
    (selectedNamespace === 'all' || d.namespace === selectedNamespace),
  );
  const filteredPods = pods.filter((p) =>
    (p.name || '').toLowerCase().includes(search.toLowerCase()) &&
    (selectedNamespace === 'all' || p.namespace === selectedNamespace),
  );

  const getPodStatusBadge = (status: string) => {
    const map: Record<string, string> = {
      Running: 'bg-emerald-500/20 text-emerald-400 border-emerald-500/30',
      Pending: 'bg-yellow-500/20 text-yellow-400 border-yellow-500/30',
      Failed: 'bg-red-500/20 text-red-400 border-red-500/30',
      Succeeded: 'bg-blue-500/20 text-blue-400 border-blue-500/30',
    };
    return <Badge className={map[status] || 'bg-slate-500/20 text-slate-400 border-slate-500/30'}>{status || 'Unknown'}</Badge>;
  };

  const handleQuickScale = async (dep: any, delta: number) => {
    const key = `scale-${dep.name}`;
    setActionLoading((prev) => ({ ...prev, [key]: 'loading' }));
    try {
      const newReplicas = (dep.replicas || 0) + delta;
      if (newReplicas < 0) return;
      await kubernetesApi.scaleDeployment(selectedCluster, dep.namespace, dep.name, newReplicas);
      toast({ title: '扩缩容成功', description: `${dep.name} → ${newReplicas} 副本` });
      loadData();
    } catch (e: any) {
      toast({ title: '操作失败', description: e?.message || String(e), variant: 'destructive' });
    } finally {
      setActionLoading((prev) => { const n = { ...prev }; delete n[key]; return n; });
    }
  };

  // Show detail view if a deployment is selected
  if (selectedDeployment) {
    return (
      <DeploymentDetail
        clusterCode={selectedCluster}
        namespace={selectedDeployment.namespace}
        deploymentName={selectedDeployment.name}
        onBack={() => { setSelectedDeployment(null); loadData(); }}
      />
    );
  }

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-slate-100">工作负载</h1>
          <p className="text-sm text-slate-500 mt-1">Deployment 与 Pod 运行状态</p>
        </div>
        <div className="flex items-center gap-2">
          <Select value={selectedCluster} onValueChange={(v) => { setSelectedCluster(v); setSelectedNamespace('all'); }}>
            <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={c.code || String(c.id)}>{c.name}</SelectItem>
              ))}
            </SelectContent>
          </Select>
          <Select value={selectedNamespace} onValueChange={setSelectedNamespace}>
            <SelectTrigger className="w-40 h-9 bg-slate-800/50 border-slate-700 text-slate-200">
              <SelectValue placeholder="命名空间" />
            </SelectTrigger>
            <SelectContent className="bg-slate-800 border-slate-700 max-h-[300px]">
              <SelectItem value="all">全部命名空间</SelectItem>
              {namespaces.map((ns) => (
                <SelectItem key={ns} value={ns}>{ns}</SelectItem>
              ))}
            </SelectContent>
          </Select>
          <Button variant="outline" size="icon" className="h-9 w-9 border-slate-700 text-slate-400" onClick={loadData} disabled={loading}>
            {loading ? <Loader2 className="h-4 w-4 animate-spin" /> : <RefreshCw className="h-4 w-4" />}
          </Button>
        </div>
      </div>

      <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
        {[
          { label: 'Deployment', value: deployments.length, icon: <Boxes className="h-5 w-5" />, color: 'text-rose-400' },
          { label: 'Pod 总数', value: pods.length, icon: <Container className="h-5 w-5" />, color: 'text-blue-400' },
          { label: 'Running', value: pods.filter((p) => p.status === 'Running').length, icon: <Container className="h-5 w-5" />, color: 'text-emerald-400' },
          { label: '异常', value: pods.filter((p) => ['Failed', 'Pending'].includes(p.status)).length, icon: <Container className="h-5 w-5" />, color: 'text-red-400' },
        ].map((s) => (
          <Card key={s.label} className="bg-slate-900 border-slate-800">
            <CardContent className="p-4">
              <div className="flex items-center justify-between">
                <div>
                  <p className="text-sm text-slate-500">{s.label}</p>
                  <p className={`text-2xl font-bold ${s.color}`}>{s.value}</p>
                </div>
                <div className="opacity-60">{s.icon}</div>
              </div>
            </CardContent>
          </Card>
        ))}
      </div>

      <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..." value={search} onChange={(e) => setSearch(e.target.value)} className="pl-9 h-9 bg-slate-800/50 border-slate-700 text-slate-200" />
      </div>

      <Tabs value={activeTab} onValueChange={setActiveTab}>
        <TabsList className="bg-slate-800 border border-slate-700">
          <TabsTrigger value="deployments" className="data-[state=active]:bg-slate-700">Deployment ({filteredDeps.length})</TabsTrigger>
          <TabsTrigger value="pods" className="data-[state=active]:bg-slate-700">Pod ({filteredPods.length})</TabsTrigger>
        </TabsList>

        <TabsContent value="deployments">
          <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">名称</TableHead>
                    <TableHead className="text-slate-400">命名空间</TableHead>
                    <TableHead className="text-slate-400">副本</TableHead>
                    <TableHead className="text-slate-400">镜像</TableHead>
                    <TableHead className="text-slate-400 w-[140px]">操作</TableHead>
                  </TableRow>
                </TableHeader>
                <TableBody>
                  {loading ? (
                    <TableRow><TableCell colSpan={5} 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>
                  ) : filteredDeps.length === 0 ? (
                    <TableRow><TableCell colSpan={5} className="text-center text-slate-500 py-12"><Boxes className="h-8 w-8 mx-auto mb-2 opacity-50" />暂无 Deployment</TableCell></TableRow>
                  ) : (
                    filteredDeps.map((d) => (
                      <TableRow key={d.id || d.name} className="border-slate-800 hover:bg-slate-800/30 cursor-pointer"
                        onClick={() => setSelectedDeployment({ name: d.name, namespace: d.namespace })}>
                        <TableCell className="font-medium text-slate-200">{d.name}</TableCell>
                        <TableCell><Badge variant="outline" className="border-slate-700 text-slate-400">{d.namespace}</Badge></TableCell>
                        <TableCell>
                          {(() => {
                            const ready = d.ready_replicas || 0;
                            const total = d.replicas || 0;
                            const pct = total > 0 ? (ready / total) * 100 : 0;
                            const done = ready === total;
                            return (
                              <div className="flex items-center gap-2 min-w-[100px]">
                                <div className="flex-1 h-1.5 rounded-full bg-slate-700/50 overflow-hidden">
                                  <div className={`h-full rounded-full ${done ? 'bg-emerald-500' : 'bg-yellow-500'}`} style={{ width: `${pct}%` }} />
                                </div>
                                <span className={`text-xs ${done ? 'text-emerald-400' : 'text-yellow-400'}`}>{ready}/{total}</span>
                              </div>
                            );
                          })()}
                        </TableCell>
                        <TableCell className="text-xs text-slate-500 max-w-[200px] truncate">{d.image || '-'}</TableCell>
                        <TableCell onClick={(e) => e.stopPropagation()}>
                          <div className="flex items-center gap-0.5">
                            <Button variant="ghost" size="icon" className="h-7 w-7 text-slate-400 hover:text-slate-200"
                              title="减少副本" disabled={(d.replicas || 0) <= 0}
                              onClick={() => handleQuickScale(d, -1)}>
                              <Minus className="h-3.5 w-3.5" />
                            </Button>
                            <Button variant="ghost" size="icon" className="h-7 w-7 text-slate-400 hover:text-slate-200"
                              title="增加副本" onClick={() => handleQuickScale(d, 1)}>
                              <Plus className="h-3.5 w-3.5" />
                            </Button>
                            <Button variant="ghost" size="icon" className="h-7 w-7 text-slate-400 hover:text-blue-400"
                              title="查看详情" onClick={() => setSelectedDeployment({ name: d.name, namespace: d.namespace })}>
                              <Eye className="h-3.5 w-3.5" />
                            </Button>
                          </div>
                        </TableCell>
                      </TableRow>
                    ))
                  )}
                </TableBody>
              </Table>
            </CardContent>
          </Card>
        </TabsContent>

        <TabsContent value="pods">
          <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">名称</TableHead>
                    <TableHead className="text-slate-400">命名空间</TableHead>
                    <TableHead className="text-slate-400">状态</TableHead>
                    <TableHead className="text-slate-400">节点</TableHead>
                    <TableHead className="text-slate-400">CPU</TableHead>
                    <TableHead className="text-slate-400">内存</TableHead>
                    <TableHead className="text-slate-400">重启</TableHead>
                    <TableHead className="text-slate-400">镜像</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>
                  ) : filteredPods.length === 0 ? (
                    <TableRow><TableCell colSpan={8} className="text-center text-slate-500 py-12"><Container className="h-8 w-8 mx-auto mb-2 opacity-50" />暂无 Pod</TableCell></TableRow>
                  ) : (
                    filteredPods.map((p) => (
                      <TableRow key={p.id} className="border-slate-800 hover:bg-slate-800/30">
                        <TableCell className="font-medium text-slate-200">{p.name}</TableCell>
                        <TableCell><Badge variant="outline" className="border-slate-700 text-slate-400">{p.namespace}</Badge></TableCell>
                        <TableCell>{getPodStatusBadge(p.status)}</TableCell>
                        <TableCell className="text-sm text-slate-400">{p.node_name || '-'}</TableCell>
                        <TableCell className="text-sm text-cyan-400">{p.cpu_usage_m || '-'}</TableCell>
                        <TableCell className="text-sm text-amber-400">{p.mem_usage_mi || '-'}</TableCell>
                        <TableCell className={p.restart_count > 0 ? 'text-yellow-400' : 'text-slate-500'}>{p.restart_count || 0}</TableCell>
                        <TableCell className="text-xs text-slate-500 max-w-[200px] truncate">{p.image || '-'}</TableCell>
                      </TableRow>
                    ))
                  )}
                </TableBody>
              </Table>
            </CardContent>
          </Card>
        </TabsContent>
      </Tabs>
    </div>
  );
}