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 { Textarea } from '@/components/ui/textarea';
import {
  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
} from '@/components/ui/table';
import {
  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
} from '@/components/ui/select';
import {
  Dialog, DialogContent, DialogHeader, DialogTitle, DialogDescription, DialogFooter,
} from '@/components/ui/dialog';
import {
  Plus, Trash2, Edit3, Key, Globe, Shield, Eye, EyeOff, RefreshCw,
} from 'lucide-react';
import { credentialApi } from '@/services/api';
import { useConfirm } from '@/components/ui/confirm-dialog';
import { toast } from 'sonner';

type CredentialType = 'ssh_key' | 'api_token' | 'password' | 'access_key';

const TYPE_CONFIG: Record<CredentialType, { label: string; icon: typeof Key; color: string }> = {
  ssh_key: { label: 'SSH 密钥', icon: Key, color: 'text-amber-400' },
  api_token: { label: 'API Token', icon: Globe, color: 'text-blue-400' },
  password: { label: '密码', icon: Shield, color: 'text-emerald-400' },
  access_key: { label: 'AK密钥对', icon: Key, color: 'text-purple-400' },
};

interface CredentialItem {
  id: number;
  name: string;
  type: CredentialType;
  preview: string;
  description: string;
  created_at: string;
  updated_at: string;
}

const EMPTY_FORM = { name: '', type: 'password' as CredentialType, content: '', description: '' };

export function CredentialManager() {
  const confirm = useConfirm();
  const [credentials, setCredentials] = useState<CredentialItem[]>([]);
  const [loading, setLoading] = useState(true);

  // 表单状态
  const [formOpen, setFormOpen] = useState(false);
  const [editingId, setEditingId] = useState<number | null>(null);
  const [formData, setFormData] = useState(EMPTY_FORM);
  const [saving, setSaving] = useState(false);
  const [showContent, setShowContent] = useState(false);

  const fetchList = useCallback(async () => {
    try {
      setLoading(true);
      const res: any = await credentialApi.list();
      setCredentials(res?.list || []);
    } catch (e) {
      console.error('加载凭据列表失败:', e);
    } finally {
      setLoading(false);
    }
  }, []);

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

  const openCreate = () => {
    setEditingId(null);
    setFormData(EMPTY_FORM);
    setShowContent(false);
    setFormOpen(true);
  };

  const openEdit = (item: CredentialItem) => {
    setEditingId(item.id);
    setFormData({
      name: item.name,
      type: item.type,
      content: '',   // 编辑时空内容表示不更新
      description: item.description || '',
    });
    setShowContent(false);
    setFormOpen(true);
  };

  const handleSave = async () => {
    if (!formData.name || (!editingId && !formData.content)) return;
    try {
      setSaving(true);
      if (editingId) {
        await credentialApi.update(editingId, {
          name: formData.name,
          type: formData.type,
          ...(formData.content ? { content: formData.content } : {}),
          description: formData.description,
        });
        toast.success('凭据已更新');
      } else {
        await credentialApi.create(formData);
        toast.success('凭据已创建');
      }
      setFormOpen(false);
      fetchList();
    } catch (e: any) {
      toast.error(e?.message || '操作失败');
    } finally {
      setSaving(false);
    }
  };

  const handleDelete = async (id: number) => {
    const item = credentials.find(c => c.id === id);
    const ok = await confirm({
      title: '删除凭据',
      description: `确定删除「${item?.name || id}」吗？删除后无法恢复，关联的服务器将无法使用此凭据连接。`,
      confirmText: '删除',
      variant: 'destructive',
    });
    if (!ok) return;
    try {
      await credentialApi.delete(id);
      toast.success('凭据已删除');
      fetchList();
    } catch (e) {
      toast.error('删除失败');
    }
  };

  const typeIcon = (type: CredentialType) => {
    const cfg = TYPE_CONFIG[type];
    const Icon = cfg.icon;
    return <Icon className={`h-4 w-4 ${cfg.color}`} />;
  };

  const typeBadge = (type: CredentialType) => {
    const cfg = TYPE_CONFIG[type];
    const bgMap: Record<string, string> = {
      ssh_key: 'bg-amber-500/20 text-amber-400',
      api_token: 'bg-blue-500/20 text-blue-400',
      password: 'bg-emerald-500/20 text-emerald-400',
      access_key: 'bg-purple-500/20 text-purple-400',
    };
    return (
      <Badge className={`border-0 text-xs ${bgMap[type] || ''}`}>
        {cfg.label}
      </Badge>
    );
  };

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-[var(--dg-text-primary)]">凭证配置</h1>
          <p className="text-sm text-[var(--dg-text-muted)] mt-1">
            SSH 密钥、API Token、密码、AK密钥对等敏感信息统一加密管理
          </p>
        </div>
        <div className="flex items-center gap-2">
          <Button
            variant="outline"
            className="border-[var(--dg-border)] text-[var(--dg-text-secondary)]"
            onClick={fetchList}
          >
            <RefreshCw className="h-4 w-4 mr-2" />
            刷新
          </Button>
          <Button className="bg-[var(--dg-blue)] hover:opacity-90 text-white" onClick={openCreate}>
            <Plus className="h-4 w-4 mr-2" />
            添加凭据
          </Button>
        </div>
      </div>

      {/* Table */}
      <Card className="bg-[var(--dg-bg-secondary)] border-[var(--dg-border)]">
        <CardContent className="p-0">
          <Table>
            <TableHeader>
              <TableRow className="border-[var(--dg-border)] hover:bg-transparent">
                <TableHead className="text-[var(--dg-text-secondary)]">名称</TableHead>
                <TableHead className="text-[var(--dg-text-secondary)]">类型</TableHead>
                <TableHead className="text-[var(--dg-text-secondary)]">内容预览</TableHead>
                <TableHead className="text-[var(--dg-text-secondary)]">描述</TableHead>
                <TableHead className="text-[var(--dg-text-secondary)]">更新时间</TableHead>
                <TableHead className="text-[var(--dg-text-secondary)] text-right">操作</TableHead>
              </TableRow>
            </TableHeader>
            <TableBody>
              {loading ? (
                <TableRow className="border-[var(--dg-border)]">
                  <TableCell colSpan={6} className="text-center text-[var(--dg-text-muted)] py-12">
                    <RefreshCw className="h-5 w-5 animate-spin mx-auto mb-2" />
                    加载中...
                  </TableCell>
                </TableRow>
              ) : credentials.length === 0 ? (
                <TableRow className="border-[var(--dg-border)]">
                  <TableCell colSpan={6} className="text-center text-[var(--dg-text-muted)] py-12">
                    暂无凭据，点击「添加凭据」创建
                  </TableCell>
                </TableRow>
              ) : (
                credentials.map((cred) => (
                  <TableRow key={cred.id} className="border-[var(--dg-border)] hover:bg-[var(--dg-bg-hover)]">
                    <TableCell className="font-medium text-[var(--dg-text-primary)]">
                      <div className="flex items-center gap-2">
                        {typeIcon(cred.type)}
                        {cred.name}
                      </div>
                    </TableCell>
                    <TableCell>{typeBadge(cred.type)}</TableCell>
                    <TableCell>
                      <code className="text-xs text-[var(--dg-text-muted)] bg-[var(--dg-bg-tertiary)] px-2 py-0.5 rounded">
                        {cred.preview || '****'}
                      </code>
                    </TableCell>
                    <TableCell className="text-sm text-[var(--dg-text-secondary)] max-w-[200px] truncate" title={cred.description}>
                      {cred.description || '-'}
                    </TableCell>
                    <TableCell className="text-sm text-[var(--dg-text-muted)]">
                      {cred.updated_at ? new Date(cred.updated_at).toLocaleDateString('zh-CN') : '-'}
                    </TableCell>
                    <TableCell className="text-right">
                      <div className="flex items-center justify-end gap-1">
                        <Button
                          variant="ghost"
                          size="icon"
                          className="h-8 w-8 text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)]"
                          onClick={() => openEdit(cred)}
                        >
                          <Edit3 className="h-4 w-4" />
                        </Button>
                        <Button
                          variant="ghost"
                          size="icon"
                          className="h-8 w-8 text-[var(--dg-text-muted)] hover:text-red-400"
                          onClick={() => handleDelete(cred.id)}
                        >
                          <Trash2 className="h-4 w-4" />
                        </Button>
                      </div>
                    </TableCell>
                  </TableRow>
                ))
              )}
            </TableBody>
          </Table>
        </CardContent>
      </Card>

      {/* Form Dialog */}
      <Dialog open={formOpen} onOpenChange={setFormOpen}>
        <DialogContent className="max-w-lg bg-[var(--dg-bg-primary)] border-[var(--dg-border)] text-[var(--dg-text-primary)]">
          <DialogHeader>
            <DialogTitle>{editingId ? '编辑凭据' : '添加凭据'}</DialogTitle>
            <DialogDescription className="sr-only">
              {editingId ? '编辑凭据信息，留空内容不更新' : '添加新的凭据'}
            </DialogDescription>
          </DialogHeader>

          <div className="space-y-4">
            {/* 名称 */}
            <div>
              <label className="block text-sm font-medium text-[var(--dg-text-secondary)] mb-1">
                名称 <span className="text-red-400">*</span>
              </label>
              <Input
                placeholder="如: 生产环境SSH密钥"
                value={formData.name}
                onChange={(e) => setFormData({ ...formData, name: e.target.value })}
                className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]"
              />
            </div>

            {/* 类型 */}
            <div>
              <label className="block text-sm font-medium text-[var(--dg-text-secondary)] mb-1">类型</label>
              <Select
                value={formData.type}
                onValueChange={(v) => setFormData({ ...formData, type: v as CredentialType })}
              >
                <SelectTrigger className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]">
                  <SelectValue />
                </SelectTrigger>
                <SelectContent className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]">
                  <SelectItem value="ssh_key">
                    <span className="flex items-center gap-2">
                      <Key className="h-4 w-4 text-amber-400" /> SSH 密钥
                    </span>
                  </SelectItem>
                  <SelectItem value="api_token">
                    <span className="flex items-center gap-2">
                      <Globe className="h-4 w-4 text-blue-400" /> API Token
                    </span>
                  </SelectItem>
                  <SelectItem value="password">
                    <span className="flex items-center gap-2">
                      <Shield className="h-4 w-4 text-emerald-400" /> 密码
                    </span>
                  </SelectItem>
                  <SelectItem value="access_key">
                    <span className="flex items-center gap-2">
                      <Key className="h-4 w-4 text-purple-400" /> AK密钥对
                    </span>
                  </SelectItem>
                </SelectContent>
              </Select>
            </div>

            {/* 内容 */}
            <div>
              <label className="block text-sm font-medium text-[var(--dg-text-secondary)] mb-1">
                {formData.type === 'ssh_key' ? 'SSH 私钥' : formData.type === 'api_token' ? 'Token' : formData.type === 'access_key' ? 'AK/SK (每行一对，用空格或逗号分隔)' : '密码'}
                {!editingId && <span className="text-red-400"> *</span>}
                {editingId && <span className="text-xs text-[var(--dg-text-muted)] ml-1">（留空不更新）</span>}
              </label>
              <div className="relative">
                <Textarea
                  placeholder={
                    formData.type === 'ssh_key'
                      ? '-----BEGIN OPENSSH PRIVATE KEY-----\n...'
                      : formData.type === 'api_token'
                        ? '***'
                        : formData.type === 'access_key'
                          ? 'AKID*** SK***\nAKID*** SK***'
                          : '输入密码'
                  }
                  value={formData.content}
                  onChange={(e) => setFormData({ ...formData, content: e.target.value })}
                  className={`bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)] min-h-[100px] ${formData.type === 'ssh_key' ? 'font-mono text-xs' : showContent ? '' : 'text-security-disc'}`}
                />
                <Button
                  variant="ghost"
                  size="icon"
                  className="absolute top-2 right-2 h-7 w-7 text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)]"
                  onClick={() => setShowContent(!showContent)}
                  title={showContent ? '隐藏' : '显示'}
                >
                  {showContent ? <EyeOff className="h-4 w-4" /> : <Eye className="h-4 w-4" />}
                </Button>
              </div>
            </div>

            {/* 描述 */}
            <div>
              <label className="block text-sm font-medium text-[var(--dg-text-secondary)] mb-1">描述</label>
              <Input
                placeholder="可选备注"
                value={formData.description}
                onChange={(e) => setFormData({ ...formData, description: e.target.value })}
                className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]"
              />
            </div>

            {/* 安全提示 */}
            <div className="p-3 rounded-lg bg-amber-500/10 border border-amber-500/20">
              <p className="text-xs text-amber-400 flex items-center gap-2">
                <Shield className="h-3.5 w-3.5" />
                凭据内容使用 AES-256-GCM 加密存储，仅在服务器端解密使用
              </p>
            </div>
          </div>

          <DialogFooter>
            <Button variant="outline" className="border-[var(--dg-border)]" onClick={() => setFormOpen(false)}>
              取消
            </Button>
            <Button
              className="bg-[var(--dg-blue)] hover:opacity-90 text-white"
              onClick={handleSave}
              disabled={saving || !formData.name}
            >
              {saving ? '保存中...' : editingId ? '保存' : '创建'}
            </Button>
          </DialogFooter>
        </DialogContent>
      </Dialog>
    </div>
  );
}