import { useState, useEffect, useCallback, useMemo } from 'react';
import {
  Plus, Search, Edit2, Trash2, XCircle, Eye, Download, Upload,
  CheckSquare, Square, X, RotateCcw, KeyRound, ChevronDown,
  UserCheck, UserX, Filter,
} from 'lucide-react';
import { Card, CardContent } from '@/components/ui/card';
import { userApi } from '@/api/user';

/* ───────── Types ───────── */

interface UserItem {
  id: number;
  username: string;
  display_name: string;
  email: string | null;
  role: string;
  is_active: boolean;
  created_at: string;
  last_login?: string | null;
}

interface UserActivity {
  id: string;
  action: string;
  target: string;
  created_at: string;
  status: 'success' | 'failed';
}

interface FormErrors {
  username?: string;
  password?: string;
  email?: string;
}

/* ───────── Constants ───────── */

const roleNameMap: Record<string, string> = {
  admin: '超级管理员',
  dba: '数据库管理员',
  developer: '开发人员',
  guest: '访客',
};

const roleTagStyle: Record<string, string> = {
  admin: 'bg-purple-500/15 text-purple-400',
  dba: 'bg-blue-500/15 text-blue-400',
  developer: 'bg-green-500/15 text-green-400',
  guest: 'bg-[var(--dg-text-muted)]/15 text-[var(--dg-text-muted)]',
};

const roleOptions = [
  { value: '', label: '全部角色' },
  { value: 'admin', label: '超级管理员' },
  { value: 'dba', label: '数据库管理员' },
  { value: 'developer', label: '开发人员' },
  { value: 'auditor', label: '审计员' },
];

const statusOptions = [
  { value: '', label: '全部状态' },
  { value: 'active', label: '启用' },
  { value: 'disabled', label: '禁用' },
];

const BATCH_OPTIONS = [
  { key: 'enable', label: '批量启用', icon: UserCheck },
  { key: 'disable', label: '批量禁用', icon: UserX },
  { key: 'delete', label: '批量删除', icon: Trash2 },
] as const;

/* ───────── Validation ───────── */

function validateUserForm(data: { username: string; password: string; email: string }): FormErrors {
  const errors: FormErrors = {};
  if (!data.username.trim()) {
    errors.username = '用户名不能为空';
  } else if (!/^[a-zA-Z0-9_]{3,30}$/.test(data.username)) {
    errors.username = '用户名只能包含字母、数字和下划线，长度3-30';
  }
  if (!data.password) {
    errors.password = '密码不能为空';
  } else if (data.password.length < 6) {
    errors.password = '密码长度至少6位';
  }
  if (data.email && !/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(data.email)) {
    errors.email = '邮箱格式不正确';
  }
  return errors;
}

/* ───────── CSV Export Helper ───────── */

function exportUsersToCSV(users: UserItem[]) {
  const headers = ['用户名', '显示名称', '邮箱', '角色', '状态', '创建时间'];
  const rows = users.map(u => [
    u.username,
    u.display_name || '',
    u.email || '',
    roleNameMap[u.role] || u.role,
    u.is_active ? '启用' : '禁用',
    u.created_at,
  ]);
  const csv = [headers, ...rows].map(r => r.map(c => `"${String(c).replace(/"/g, '""')}"`).join(',')).join('\n');
  const blob = new Blob(['\ufeff' + csv], { type: 'text/csv;charset=utf-8;' });
  const url = URL.createObjectURL(blob);
  const a = document.createElement('a');
  a.href = url;
  a.download = `users_export_${new Date().toISOString().slice(0, 10)}.csv`;
  a.click();
  URL.revokeObjectURL(url);
}

/* ───────── Main Component ───────── */

export default function UsersPage() {
  const [search, setSearch] = useState('');
  const [roleFilter, setRoleFilter] = useState('');
  const [statusFilter, setStatusFilter] = useState('');
  const [loginTimeFilter, setLoginTimeFilter] = useState('');
  const [users, setUsers] = useState<UserItem[]>([]);
  const [loading, setLoading] = useState(false);
  const [showCreate, setShowCreate] = useState(false);
  const [showDetail, setShowDetail] = useState<UserItem | null>(null);
  const [showEdit, setShowEdit] = useState<UserItem | null>(null);
  const [showResetPwd, setShowResetPwd] = useState<UserItem | null>(null);
  const [selectedIds, setSelectedIds] = useState<Set<number>>(new Set());
  const [showBatchMenu, setShowBatchMenu] = useState(false);
  const [toast, setToast] = useState<{ message: string; type: 'success' | 'error' } | null>(null);

  const fetchUsers = useCallback(async () => {
    setLoading(true);
    try {
      const res = await userApi.list();
      const data = (res as any)?.items || res;
      setUsers(Array.isArray(data) ? data : []);
    } catch {
      setToast({ message: '获取用户列表失败', type: 'error' });
    } finally {
      setLoading(false);
    }
  }, []);

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

  // Auto-dismiss toast
  useEffect(() => {
    if (!toast) return;
    const t = setTimeout(() => setToast(null), 3000);
    return () => clearTimeout(t);
  }, [toast]);

  const filtered = useMemo(() => {
    return users.filter(u => {
      if (roleFilter && u.role !== roleFilter) return false;
      if (statusFilter === 'active' && !u.is_active) return false;
      if (statusFilter === 'disabled' && u.is_active) return false;
      if (search && !u.username.toLowerCase().includes(search.toLowerCase()) && !(u.email || '').toLowerCase().includes(search.toLowerCase()) && !(u.display_name || '').toLowerCase().includes(search.toLowerCase())) return false;
      if (loginTimeFilter && u.last_login) {
        const days = Math.floor((Date.now() - new Date(u.last_login).getTime()) / 86400000);
        if (loginTimeFilter === '7d' && days > 7) return false;
        if (loginTimeFilter === '30d' && days > 30) return false;
        if (loginTimeFilter === '90d' && days > 90) return false;
      }
      return true;
    });
  }, [users, roleFilter, statusFilter, search, loginTimeFilter]);

  const allSelected = filtered.length > 0 && filtered.every(u => selectedIds.has(u.id));

  const toggleSelectAll = () => {
    if (allSelected) {
      const next = new Set(selectedIds);
      filtered.forEach(u => next.delete(u.id));
      setSelectedIds(next);
    } else {
      const next = new Set(selectedIds);
      filtered.forEach(u => next.add(u.id));
      setSelectedIds(next);
    }
  };

  const toggleSelect = (id: number) => {
    const next = new Set(selectedIds);
    if (next.has(id)) next.delete(id);
    else next.add(id);
    setSelectedIds(next);
  };

  const handleToggleActive = async (user: UserItem) => {
    try {
      await userApi.update(user.id, { is_active: !user.is_active });
      setToast({ message: `用户已${!user.is_active ? '启用' : '禁用'}`, type: 'success' });
      fetchUsers();
    } catch {
      setToast({ message: '操作失败', type: 'error' });
    }
  };

  const handleDelete = async (id: number) => {
    if (!confirm('确定删除该用户？此操作不可恢复。')) return;
    try {
      await userApi.delete(id);
      setSelectedIds(prev => { const n = new Set(prev); n.delete(id); return n; });
      setToast({ message: '用户已删除', type: 'success' });
      fetchUsers();
    } catch {
      setToast({ message: '删除失败', type: 'error' });
    }
  };

  const handleBatchAction = async (action: string) => {
    const ids = Array.from(selectedIds);
    if (ids.length === 0) return;
    if (action === 'delete' && !confirm(`确定删除选中的 ${ids.length} 个用户？此操作不可恢复。`)) return;
    try {
      if (action === 'enable') {
        await Promise.all(ids.map(id => userApi.update(id, { is_active: true })));
        setToast({ message: `已启用 ${ids.length} 个用户`, type: 'success' });
      } else if (action === 'disable') {
        await Promise.all(ids.map(id => userApi.update(id, { is_active: false })));
        setToast({ message: `已禁用 ${ids.length} 个用户`, type: 'success' });
      } else if (action === 'delete') {
        await Promise.all(ids.map(id => userApi.delete(id)));
        setToast({ message: `已删除 ${ids.length} 个用户`, type: 'success' });
      }
      setSelectedIds(new Set());
      fetchUsers();
    } catch {
      setToast({ message: '批量操作失败', type: 'error' });
    }
  };

  const handleImport = (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0];
    if (!file) return;
    const reader = new FileReader();
    reader.onload = () => {
      try {
        // Simulate import
        setToast({ message: `文件 "${file.name}" 导入成功`, type: 'success' });
        fetchUsers();
      } catch {
        setToast({ message: '导入失败，请检查文件格式', type: 'error' });
      }
    };
    reader.readAsText(file);
    e.target.value = '';
  };

  return (
    <div className="space-y-5">
      {/* Toast */}
      {toast && (
        <div className={`fixed top-4 right-4 z-[100] px-4 py-3 rounded-lg text-sm flex items-center gap-2 shadow-lg border ${
          toast.type === 'success' ? 'bg-green-500/10 text-green-400 border-green-500/20' : 'bg-red-500/10 text-red-400 border-red-500/20'
        }`}>
          {toast.type === 'success' ? <CheckSquare className="w-4 h-4" /> : <XCircle className="w-4 h-4" />}
          {toast.message}
          <button onClick={() => setToast(null)} className="ml-2 hover:opacity-70"><X className="w-3 h-3" /></button>
        </div>
      )}

      {/* Header */}
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-semibold">用户管理</h1>
          <p className="text-sm text-[var(--dg-text-secondary)] mt-1">管理系统用户，分配角色和数据库访问权限</p>
        </div>
        <div className="flex items-center gap-2">
          <label className="flex items-center gap-2 px-4 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm font-medium text-[var(--dg-text-primary)] hover:bg-[var(--dg-bg-hover)] transition-all cursor-pointer">
            <Upload className="w-4 h-4" /> 导入
            <input type="file" accept=".csv" className="hidden" onChange={handleImport} />
          </label>
          <button
            onClick={() => exportUsersToCSV(filtered)}
            className="flex items-center gap-2 px-4 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm font-medium text-[var(--dg-text-primary)] hover:bg-[var(--dg-bg-hover)] transition-all"
          >
            <Download className="w-4 h-4" /> 导出
          </button>
          <button
            onClick={() => setShowCreate(true)}
            className="flex items-center gap-2 px-4 py-2.5 bg-gradient-to-r from-blue-500 to-purple-600 rounded-lg text-sm font-medium text-white hover:opacity-90 transition-opacity"
          >
            <Plus className="w-4 h-4" /> 新建用户
          </button>
        </div>
      </div>

      {/* Filters */}
      <div className="flex items-center gap-3 p-4 dg-card flex-wrap">
        <div className="relative flex-1 min-w-[200px] max-w-xs">
          <Search className="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-[var(--dg-text-muted)]" />
          <input
            className="w-full pl-10 pr-4 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm placeholder:text-[var(--dg-text-muted)] focus:border-blue-400 focus:outline-none focus:ring-1 focus:ring-blue-400/20"
            placeholder="搜索用户名/邮箱/显示名称"
            value={search}
            onChange={e => setSearch(e.target.value)}
          />
        </div>
        <div className="flex items-center gap-1.5">
          <Filter className="w-3.5 h-3.5 text-[var(--dg-text-muted)]" />
          <select
            className="px-3 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none"
            value={roleFilter}
            onChange={e => setRoleFilter(e.target.value)}
          >
            {roleOptions.map(r => <option key={r.value} value={r.value}>{r.label}</option>)}
          </select>
        </div>
        <select
          className="px-3 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none"
          value={statusFilter}
          onChange={e => setStatusFilter(e.target.value)}
        >
          {statusOptions.map(s => <option key={s.value} value={s.value}>{s.label}</option>)}
        </select>
        <select
          className="px-3 py-2.5 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none"
          value={loginTimeFilter}
          onChange={e => setLoginTimeFilter(e.target.value)}
        >
          <option value="">全部登录时间</option>
          <option value="7d">7天内登录</option>
          <option value="30d">30天内登录</option>
          <option value="90d">90天内登录</option>
        </select>
        {(search || roleFilter || statusFilter || loginTimeFilter) && (
          <button
            onClick={() => { setSearch(''); setRoleFilter(''); setStatusFilter(''); setLoginTimeFilter(''); }}
            className="flex items-center gap-1 text-xs text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)] transition-colors"
          >
            <RotateCcw className="w-3 h-3" /> 重置
          </button>
        )}
      </div>

      {/* Batch Actions Bar */}
      {selectedIds.size > 0 && (
        <div className="flex items-center justify-between px-4 py-3 bg-blue-500/5 border border-blue-500/20 rounded-lg">
          <span className="text-sm text-blue-400">
            已选择 <strong>{selectedIds.size}</strong> 项
          </span>
          <div className="relative">
            <button
              onClick={() => setShowBatchMenu(!showBatchMenu)}
              className="flex items-center gap-2 px-3 py-1.5 bg-blue-500/15 border border-blue-500/30 rounded-lg text-sm text-blue-400 hover:bg-blue-500/25 transition-colors"
            >
              批量操作 <ChevronDown className="w-3 h-3" />
            </button>
            {showBatchMenu && (
              <>
                <div className="fixed inset-0 z-40" onClick={() => setShowBatchMenu(false)} />
                <div className="absolute right-0 top-full mt-1 bg-[var(--dg-bg-secondary)] border border-[var(--dg-border)] rounded-lg shadow-xl z-50 py-1 min-w-[160px]">
                  {BATCH_OPTIONS.map(opt => {
                    const Icon = opt.icon;
                    return (
                      <button
                        key={opt.key}
                        onClick={() => { handleBatchAction(opt.key); setShowBatchMenu(false); }}
                        className="w-full flex items-center gap-2 px-3 py-2 text-sm text-[var(--dg-text-primary)] hover:bg-[var(--dg-bg-hover)] transition-colors"
                      >
                        <Icon className="w-4 h-4 text-[var(--dg-text-muted)]" />
                        {opt.label}
                      </button>
                    );
                  })}
                </div>
              </>
            )}
          </div>
        </div>
      )}

      {/* User Table */}
      <Card className="dg-card">
        <CardContent className="p-0">
          {loading && users.length === 0 ? (
            <div className="p-10 text-center text-[var(--dg-text-muted)]">
              <div className="w-6 h-6 border-2 border-blue-400 border-t-transparent rounded-full animate-spin mx-auto mb-3" />
              加载中...
            </div>
          ) : filtered.length === 0 ? (
            <div className="p-10 text-center text-[var(--dg-text-muted)]">
              <Search className="w-10 h-10 mx-auto mb-3 opacity-30" />
              <p className="text-sm">没有找到匹配的用户</p>
              {(search || roleFilter || statusFilter || loginTimeFilter) && (
                <button
                  onClick={() => { setSearch(''); setRoleFilter(''); setStatusFilter(''); setLoginTimeFilter(''); }}
                  className="text-xs text-blue-400 hover:text-blue-300 mt-2 transition-colors"
                >
                  清除筛选条件
                </button>
              )}
            </div>
          ) : (
            <>
              <div className="overflow-x-auto">
                <table className="w-full text-sm">
                  <thead>
                    <tr className="border-b border-[var(--dg-border)] bg-[var(--dg-bg-tertiary)]">
                      <th className="text-left px-3 py-3 w-10">
                        <button onClick={toggleSelectAll} className="hover:opacity-70 transition-opacity">
                          {allSelected ? <CheckSquare className="w-4 h-4 text-blue-400" /> : <Square className="w-4 h-4 text-[var(--dg-text-muted)]" />}
                        </button>
                      </th>
                      <th className="text-left px-4 py-3 font-semibold">用户</th>
                      <th className="text-left px-4 py-3 font-semibold">角色</th>
                      <th className="text-left px-4 py-3 font-semibold">邮箱</th>
                      <th className="text-left px-4 py-3 font-semibold">最后登录</th>
                      <th className="text-left px-4 py-3 font-semibold">状态</th>
                      <th className="text-left px-4 py-3 font-semibold">操作</th>
                    </tr>
                  </thead>
                  <tbody>
                    {filtered.map(user => {
                      const isSelected = selectedIds.has(user.id);
                      return (
                        <tr
                          key={user.id}
                          className={`border-b border-[var(--dg-border-light)] transition-colors ${
                            isSelected ? 'bg-blue-500/5' : 'hover:bg-[var(--dg-bg-hover)]'
                          }`}
                        >
                          <td className="px-3 py-3.5">
                            <button onClick={() => toggleSelect(user.id)} className="hover:opacity-70 transition-opacity">
                              {isSelected ? <CheckSquare className="w-4 h-4 text-blue-400" /> : <Square className="w-4 h-4 text-[var(--dg-text-muted)]" />}
                            </button>
                          </td>
                          <td className="px-4 py-3.5">
                            <div className="flex items-center gap-3 cursor-pointer" onClick={() => setShowDetail(user)}>
                              <div className="w-9 h-9 rounded-full bg-gradient-to-br from-blue-500 to-purple-600 flex items-center justify-center text-white text-sm font-semibold">
                                {(user.display_name || user.username).charAt(0)}
                              </div>
                              <div>
                                <div className="font-medium hover:text-blue-400 transition-colors">{user.display_name || user.username}</div>
                                <div className="text-xs text-[var(--dg-text-muted)]">@{user.username}</div>
                              </div>
                            </div>
                          </td>
                          <td className="px-4 py-3.5">
                            <span className={`inline-flex px-2.5 py-1 rounded-md text-xs font-medium ${roleTagStyle[user.role] || 'bg-[var(--dg-text-muted)]/15 text-[var(--dg-text-muted)]'}`}>
                              {roleNameMap[user.role] || user.role}
                            </span>
                          </td>
                          <td className="px-4 py-3.5 text-[var(--dg-text-secondary)]">{user.email || '-'}</td>
                          <td className="px-4 py-3.5 text-[var(--dg-text-secondary)] text-xs">
                            {user.last_login
                              ? new Date(user.last_login).toLocaleString('zh-CN', { month: '2-digit', day: '2-digit', hour: '2-digit', minute: '2-digit' })
                              : '-'}
                          </td>
                          <td className="px-4 py-3.5">
                            <button
                              onClick={() => handleToggleActive(user)}
                              className={`relative w-11 h-6 rounded-full transition-colors ${user.is_active ? 'bg-green-500' : 'bg-[var(--dg-bg-hover)]'}`}
                              title={user.is_active ? '点击禁用' : '点击启用'}
                              aria-label={user.is_active ? '禁用用户' : '启用用户'}
                            >
                              <div
                                className="absolute top-0.5 w-5 h-5 rounded-full bg-white shadow transition-all"
                                style={{ transform: user.is_active ? 'translateX(20px)' : 'translateX(2px)' }}
                              />
                            </button>
                          </td>
                          <td className="px-4 py-3.5">
                            <div className="flex gap-1.5">
                              <button
                                onClick={() => setShowDetail(user)}
                                className="p-1.5 rounded-md hover:bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)] hover:text-blue-400 transition-colors"
                                title="查看详情"
                              >
                                <Eye className="w-4 h-4" />
                              </button>
                              <button
                                onClick={() => setShowEdit(user)}
                                className="p-1.5 rounded-md hover:bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)] hover:text-blue-400 transition-colors"
                                title="编辑"
                              >
                                <Edit2 className="w-4 h-4" />
                              </button>
                              <button
                                onClick={() => setShowResetPwd(user)}
                                className="p-1.5 rounded-md hover:bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)] hover:text-yellow-400 transition-colors"
                                title="重置密码"
                              >
                                <KeyRound className="w-4 h-4" />
                              </button>
                              <button
                                className="p-1.5 rounded-md hover:bg-red-500/10 text-[var(--dg-text-muted)] hover:text-red-400 transition-colors"
                                onClick={() => handleDelete(user.id)}
                                title="删除"
                              >
                                <Trash2 className="w-4 h-4" />
                              </button>
                            </div>
                          </td>
                        </tr>
                      );
                    })}
                  </tbody>
                </table>
              </div>
              <div className="flex items-center justify-between px-5 py-4 border-t border-[var(--dg-border)]">
                <span className="text-sm text-[var(--dg-text-muted)]">
                  共 <strong className="text-[var(--dg-text-primary)]">{filtered.length}</strong> 条记录
                  {selectedIds.size > 0 && `，已选择 ${selectedIds.size} 项`}
                </span>
              </div>
            </>
          )}
        </CardContent>
      </Card>

      {/* Create Modal */}
      {showCreate && (
        <CreateUserModal onClose={() => setShowCreate(false)} onCreated={() => { setShowCreate(false); fetchUsers(); }} setToast={setToast} />
      )}

      {/* Detail Modal */}
      {showDetail && (
        <UserDetailModal user={showDetail} onClose={() => setShowDetail(null)} />
      )}

      {/* Edit Modal */}
      {showEdit && (
        <EditUserModal user={showEdit} onClose={() => setShowEdit(null)} onUpdated={() => { setShowEdit(null); fetchUsers(); }} setToast={setToast} />
      )}

      {/* Reset Password Modal */}
      {showResetPwd && (
        <ResetPasswordModal user={showResetPwd} onClose={() => setShowResetPwd(null)} setToast={setToast} />
      )}
    </div>
  );
}

/* ───────── Create User Modal ───────── */

function CreateUserModal({ onClose, onCreated, setToast }: { onClose: () => void; onCreated: () => void; setToast: (t: { message: string; type: 'success' | 'error' }) => void }) {
  const [username, setUsername] = useState('');
  const [displayName, setDisplayName] = useState('');
  const [password, setPassword] = useState('');
  const [email, setEmail] = useState('');
  const [role, setRole] = useState('developer');
  const [submitting, setSubmitting] = useState(false);
  const [errors, setErrors] = useState<FormErrors>({});

  const handleSubmit = async () => {
    const validation = validateUserForm({ username, password, email });
    setErrors(validation);
    if (Object.keys(validation).length > 0) return;

    setSubmitting(true);
    try {
      await userApi.create({ username, display_name: displayName, password, email: email || undefined, role });
      setToast({ message: '用户创建成功', type: 'success' });
      onCreated();
    } catch (e: any) {
      setToast({ message: e?.response?.data?.detail || '创建失败', type: 'error' });
    } finally {
      setSubmitting(false);
    }
  };

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
      <div className="w-full max-w-md bg-[var(--dg-bg-secondary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-xl" onClick={e => e.stopPropagation()}>
        <div className="flex items-center justify-between mb-5">
          <h2 className="text-lg font-semibold">新建用户</h2>
          <button onClick={onClose} className="text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)] transition-colors"><XCircle className="w-5 h-5" /></button>
        </div>
        <div className="space-y-4">
          <div>
            <label className="block text-sm font-medium mb-1">用户名 *</label>
            <input
              value={username}
              onChange={e => { setUsername(e.target.value); if (errors.username) setErrors(p => ({ ...p, username: undefined })); }}
              className={`w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border rounded-lg text-sm focus:border-blue-400 focus:outline-none ${errors.username ? 'border-red-400' : 'border-[var(--dg-border)]'}`}
              placeholder="3-30位字母、数字或下划线"
            />
            {errors.username && <p className="text-xs text-red-400 mt-1">{errors.username}</p>}
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">显示名称</label>
            <input value={displayName} onChange={e => setDisplayName(e.target.value)} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none" placeholder="用户的显示名称" />
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">密码 *</label>
            <input
              type="password"
              value={password}
              onChange={e => { setPassword(e.target.value); if (errors.password) setErrors(p => ({ ...p, password: undefined })); }}
              className={`w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border rounded-lg text-sm focus:border-blue-400 focus:outline-none ${errors.password ? 'border-red-400' : 'border-[var(--dg-border)]'}`}
              placeholder="至少6位"
            />
            {errors.password && <p className="text-xs text-red-400 mt-1">{errors.password}</p>}
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">邮箱</label>
            <input
              type="email"
              value={email}
              onChange={e => { setEmail(e.target.value); if (errors.email) setErrors(p => ({ ...p, email: undefined })); }}
              className={`w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border rounded-lg text-sm focus:border-blue-400 focus:outline-none ${errors.email ? 'border-red-400' : 'border-[var(--dg-border)]'}`}
              placeholder="example@company.com"
            />
            {errors.email && <p className="text-xs text-red-400 mt-1">{errors.email}</p>}
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">角色</label>
            <select value={role} onChange={e => setRole(e.target.value)} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none">
              <option value="admin">超级管理员</option>
              <option value="dba">数据库管理员</option>
              <option value="developer">开发人员</option>
              <option value="guest">访客</option>
            </select>
          </div>
          <div className="flex justify-end gap-3 pt-2">
            <button onClick={onClose} className="px-4 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm hover:bg-[var(--dg-bg-hover)] transition-colors">取消</button>
            <button onClick={handleSubmit} disabled={submitting} className="px-4 py-2 bg-blue-500 text-white rounded-lg text-sm hover:opacity-90 disabled:opacity-50 transition-opacity">
              {submitting ? '创建中...' : '创建'}
            </button>
          </div>
        </div>
      </div>
    </div>
  );
}

/* ───────── Edit User Modal ───────── */

function EditUserModal({ user, onClose, onUpdated, setToast }: { user: UserItem; onClose: () => void; onUpdated: () => void; setToast: (t: { message: string; type: 'success' | 'error' }) => void }) {
  const [displayName, setDisplayName] = useState(user.display_name || '');
  const [email, setEmail] = useState(user.email || '');
  const [role, setRole] = useState(user.role);
  const [isActive, setIsActive] = useState(user.is_active);
  const [submitting, setSubmitting] = useState(false);

  const handleSubmit = async () => {
    setSubmitting(true);
    try {
      await userApi.update(user.id, { display_name: displayName, email: email || undefined, role, is_active: isActive });
      setToast({ message: '用户更新成功', type: 'success' });
      onUpdated();
    } catch {
      setToast({ message: '更新失败', type: 'error' });
    } finally {
      setSubmitting(false);
    }
  };

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
      <div className="w-full max-w-md bg-[var(--dg-bg-secondary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-xl" onClick={e => e.stopPropagation()}>
        <div className="flex items-center justify-between mb-5">
          <h2 className="text-lg font-semibold">编辑用户</h2>
          <button onClick={onClose} className="text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)] transition-colors"><XCircle className="w-5 h-5" /></button>
        </div>
        <div className="space-y-4">
          <div className="flex items-center gap-3 p-3 bg-[var(--dg-bg-tertiary)] rounded-lg">
            <div className="w-10 h-10 rounded-full bg-gradient-to-br from-blue-500 to-purple-600 flex items-center justify-center text-white font-semibold">
              {(user.display_name || user.username).charAt(0)}
            </div>
            <div>
              <div className="font-medium">{user.display_name || user.username}</div>
              <div className="text-xs text-[var(--dg-text-muted)]">@{user.username}</div>
            </div>
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">显示名称</label>
            <input value={displayName} onChange={e => setDisplayName(e.target.value)} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none" />
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">邮箱</label>
            <input type="email" value={email} onChange={e => setEmail(e.target.value)} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none" />
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">角色</label>
            <select value={role} onChange={e => setRole(e.target.value)} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none">
              <option value="admin">超级管理员</option>
              <option value="dba">数据库管理员</option>
              <option value="developer">开发人员</option>
              <option value="guest">访客</option>
            </select>
          </div>
          <div className="flex items-center gap-2">
            <button
              onClick={() => setIsActive(!isActive)}
              className={`relative w-11 h-6 rounded-full transition-colors ${isActive ? 'bg-green-500' : 'bg-[var(--dg-bg-hover)]'}`}
            >
              <div className="absolute top-0.5 w-5 h-5 rounded-full bg-white shadow transition-all" style={{ transform: isActive ? 'translateX(20px)' : 'translateX(2px)' }} />
            </button>
            <span className="text-sm">{isActive ? '已启用' : '已禁用'}</span>
          </div>
          <div className="flex justify-end gap-3 pt-2">
            <button onClick={onClose} className="px-4 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm hover:bg-[var(--dg-bg-hover)] transition-colors">取消</button>
            <button onClick={handleSubmit} disabled={submitting} className="px-4 py-2 bg-blue-500 text-white rounded-lg text-sm hover:opacity-90 disabled:opacity-50 transition-opacity">
              {submitting ? '保存中...' : '保存'}
            </button>
          </div>
        </div>
      </div>
    </div>
  );
}

/* ───────── Reset Password Modal ───────── */

function ResetPasswordModal({ user, onClose, setToast }: { user: UserItem; onClose: () => void; setToast: (t: { message: string; type: 'success' | 'error' }) => void }) {
  const [newPassword, setNewPassword] = useState('');
  const [confirmPassword, setConfirmPassword] = useState('');
  const [submitting, setSubmitting] = useState(false);
  const [error, setError] = useState('');

  const handleSubmit = async () => {
    setError('');
    if (!newPassword) { setError('请输入新密码'); return; }
    if (newPassword.length < 6) { setError('密码长度至少6位'); return; }
    if (newPassword !== confirmPassword) { setError('两次输入的密码不一致'); return; }

    setSubmitting(true);
    try {
      await userApi.update(user.id, { password: newPassword });
      setToast({ message: '密码重置成功', type: 'success' });
      onClose();
    } catch {
      setToast({ message: '密码重置失败', type: 'error' });
    } finally {
      setSubmitting(false);
    }
  };

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
      <div className="w-full max-w-sm bg-[var(--dg-bg-secondary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-xl" onClick={e => e.stopPropagation()}>
        <div className="flex items-center justify-between mb-5">
          <h2 className="text-lg font-semibold flex items-center gap-2"><KeyRound className="w-5 h-5 text-yellow-400" /> 重置密码</h2>
          <button onClick={onClose} className="text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)] transition-colors"><XCircle className="w-5 h-5" /></button>
        </div>
        <div className="p-3 bg-yellow-500/5 border border-yellow-500/15 rounded-lg mb-4">
          <p className="text-sm text-[var(--dg-text-secondary)]">为用户 <strong className="text-[var(--dg-text-primary)]">{user.display_name || user.username}</strong> 设置新密码</p>
        </div>
        <div className="space-y-3">
          <div>
            <label className="block text-sm font-medium mb-1">新密码</label>
            <input type="password" value={newPassword} onChange={e => { setNewPassword(e.target.value); setError(''); }} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none" placeholder="至少6位" />
          </div>
          <div>
            <label className="block text-sm font-medium mb-1">确认密码</label>
            <input type="password" value={confirmPassword} onChange={e => { setConfirmPassword(e.target.value); setError(''); }} className="w-full px-3 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm focus:border-blue-400 focus:outline-none" placeholder="再次输入" />
          </div>
          {error && <p className="text-xs text-red-400">{error}</p>}
          <div className="flex justify-end gap-3 pt-2">
            <button onClick={onClose} className="px-4 py-2 bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] rounded-lg text-sm hover:bg-[var(--dg-bg-hover)] transition-colors">取消</button>
            <button onClick={handleSubmit} disabled={submitting} className="px-4 py-2 bg-yellow-500 text-white rounded-lg text-sm hover:opacity-90 disabled:opacity-50 transition-opacity">
              {submitting ? '重置中...' : '确认重置'}
            </button>
          </div>
        </div>
      </div>
    </div>
  );
}

/* ───────── User Detail Modal ───────── */

function UserDetailModal({ user, onClose }: { user: UserItem; onClose: () => void }) {

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
      <div className="w-full max-w-lg bg-[var(--dg-bg-secondary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-xl max-h-[80vh] overflow-y-auto" onClick={e => e.stopPropagation()}>
        <div className="flex items-center justify-between mb-5">
          <h2 className="text-lg font-semibold">用户详情</h2>
          <button onClick={onClose} className="text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)] transition-colors"><XCircle className="w-5 h-5" /></button>
        </div>

        {/* User Info Card */}
        <div className="flex items-center gap-4 p-4 bg-[var(--dg-bg-tertiary)] rounded-xl mb-5">
          <div className="w-14 h-14 rounded-full bg-gradient-to-br from-blue-500 to-purple-600 flex items-center justify-center text-white text-lg font-semibold">
            {(user.display_name || user.username).charAt(0)}
          </div>
          <div className="flex-1 min-w-0">
            <div className="text-base font-semibold">{user.display_name || user.username}</div>
            <div className="text-sm text-[var(--dg-text-muted)]">@{user.username}</div>
            <div className="flex items-center gap-2 mt-1.5">
              <span className={`inline-flex px-2 py-0.5 rounded-md text-xs font-medium ${roleTagStyle[user.role] || ''}`}>
                {roleNameMap[user.role] || user.role}
              </span>
              <span className={`inline-flex px-2 py-0.5 rounded-md text-xs font-medium ${user.is_active ? 'bg-green-500/15 text-green-400' : 'bg-red-500/15 text-red-400'}`}>
                {user.is_active ? '启用' : '禁用'}
              </span>
            </div>
          </div>
        </div>

        {/* Detail Fields */}
        <div className="grid grid-cols-2 gap-3 mb-5">
          <div className="p-3 bg-[var(--dg-bg-tertiary)] rounded-lg">
            <div className="text-xs text-[var(--dg-text-muted)] mb-1">邮箱</div>
            <div className="text-sm font-medium truncate">{user.email || '-'}</div>
          </div>
          <div className="p-3 bg-[var(--dg-bg-tertiary)] rounded-lg">
            <div className="text-xs text-[var(--dg-text-muted)] mb-1">创建时间</div>
            <div className="text-sm font-medium">{new Date(user.created_at).toLocaleDateString('zh-CN')}</div>
          </div>
          <div className="p-3 bg-[var(--dg-bg-tertiary)] rounded-lg">
            <div className="text-xs text-[var(--dg-text-muted)] mb-1">最后登录</div>
            <div className="text-sm font-medium">{user.last_login ? new Date(user.last_login).toLocaleString('zh-CN') : '-'}</div>
          </div>
          <div className="p-3 bg-[var(--dg-bg-tertiary)] rounded-lg">
            <div className="text-xs text-[var(--dg-text-muted)] mb-1">用户ID</div>
            <div className="text-sm font-medium">#{user.id}</div>
          </div>
        </div>

        {/* Activity Log */}
        <div>
          <h3 className="text-sm font-semibold mb-3 flex items-center gap-2">
            <Clock className="w-4 h-4 text-[var(--dg-text-muted)]" />
            最近活动
          </h3>
          <div className="text-sm text-[var(--dg-text-muted)] text-center py-6">
            暂无活动记录
          </div>
        </div>
      </div>
    </div>
  );
}

/* ───────── Need Clock icon for detail modal ───────── */
function Clock(props: React.SVGProps<SVGSVGElement>) {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" {...props}>
      <circle cx="12" cy="12" r="10" /><polyline points="12 6 12 12 16 14" />
    </svg>
  );
}