import {
  AuditOutlined,
  DashboardOutlined,
  FileSearchOutlined,
  LogoutOutlined,
  MenuFoldOutlined,
  MenuUnfoldOutlined,
  OrderedListOutlined,
  SettingOutlined,
  ShopOutlined,
  TeamOutlined,
  UnorderedListOutlined,
  UserOutlined,
} from '@ant-design/icons'
import { App, Button, Dropdown, Layout, Menu, Space, Typography } from 'antd'
import type { MenuProps } from 'antd'
import { useMemo, useState } from 'react'
import { Outlet, useLocation, useNavigate } from 'react-router'

import { logoutAdmin } from '@/services/admin'
import {
  clearAdminSession,
  getAdminRole,
  getAdminTokenExpiresAt,
  getAdminUsername,
} from '@/utils/admin-auth'
import { formatAdminDateTime } from '@/utils/admin-time'

const SIDEBAR_COLLAPSED_KEY = 'react-admin-sidebar-collapsed'

export default function AdminLayout() {
  const navigate = useNavigate()
  const location = useLocation()
  const { message } = App.useApp()
  const [collapsed, setCollapsed] = useState(
    () => window.localStorage.getItem(SIDEBAR_COLLAPSED_KEY) === '1',
  )
  const role = getAdminRole()
  const username = getAdminUsername() || 'admin'
  const expiresAt = getAdminTokenExpiresAt()

  const menuItems = useMemo<MenuProps['items']>(() => {
    const operationItems: MenuProps['items'] = [
      { key: '/admin/dashboard', icon: <DashboardOutlined />, label: '概览' },
      { key: '/admin/orders', icon: <OrderedListOutlined />, label: '订单' },
      { key: '/admin/tasks', icon: <UnorderedListOutlined />, label: '任务' },
      { key: '/admin/cloudtentacles-records', icon: <FileSearchOutlined />, label: '发货记录' },
    ]

    const items: MenuProps['items'] = [
      {
        key: 'group-operation',
        type: 'group',
        label: '运营',
        children: operationItems,
      },
    ]

    if (role === 'admin') {
      items.push(
        {
          key: 'group-config',
          type: 'group',
          label: '配置',
          children: [
            { key: '/admin/users', icon: <TeamOutlined />, label: '后台用户' },
            { key: '/admin/platform-shops', icon: <SettingOutlined />, label: '平台配置' },
            { key: '/admin/platform-fulfillment', icon: <ShopOutlined />, label: '履约配置' },
          ],
        },
        {
          key: 'group-system',
          type: 'group',
          label: '系统',
          children: [{ key: '/admin/audit-logs', icon: <AuditOutlined />, label: '审计日志' }],
        },
      )
    }

    return items
  }, [role])

  async function submitLogout() {
    try {
      await logoutAdmin()
    } catch {
      // 后端退出是无状态的，本地清理优先。
    } finally {
      clearAdminSession()
      message.success('已退出后台')
      navigate('/admin/login', { replace: true })
    }
  }

  function toggleCollapsed() {
    const next = !collapsed
    setCollapsed(next)
    window.localStorage.setItem(SIDEBAR_COLLAPSED_KEY, next ? '1' : '0')
  }

  const selectedKey = resolveSelectedKey(location.pathname)

  return (
    <Layout className="admin-shell">
      <Layout.Sider
        width={232}
        collapsedWidth={72}
        collapsed={collapsed}
        className="admin-sider"
        trigger={null}
      >
        <div className="admin-sider-inner">
          <div className="admin-brand">
            <div className="admin-brand-copy">
              <strong>{collapsed ? 'OS' : '运营后台'}</strong>
              {!collapsed ? <span>订单与交付管理</span> : null}
            </div>
            <Button
              className="admin-collapse-button"
              aria-label={collapsed ? '展开导航' : '折叠导航'}
              icon={collapsed ? <MenuUnfoldOutlined /> : <MenuFoldOutlined />}
              onClick={toggleCollapsed}
            />
          </div>

          {!collapsed ? (
            <div className="admin-sidebar-profile">
              <Typography.Text strong>{username}</Typography.Text>
              <Typography.Text type="secondary">{roleLabel(role)}</Typography.Text>
              {expiresAt ? (
                <Typography.Text type="secondary">
                  {formatAdminDateTime(expiresAt)} 到期
                </Typography.Text>
              ) : null}
            </div>
          ) : null}

          <Menu
            mode="inline"
            inlineIndent={16}
            selectedKeys={[selectedKey]}
            items={menuItems}
            className="admin-menu"
            onClick={({ key }) => navigate(String(key))}
          />

          <div className="admin-sider-footer">
            <Button
              block={!collapsed}
              icon={<LogoutOutlined />}
              onClick={submitLogout}
              aria-label="退出登录"
            >
              {collapsed ? null : '退出登录'}
            </Button>
          </div>
        </div>
      </Layout.Sider>
      <Layout className="admin-main-shell">
        <Layout.Header className="admin-topbar">
          <Space className="admin-user" size={12}>
            <Dropdown
              menu={{
                items: [{ key: 'logout', label: '退出登录' }],
                onClick: submitLogout,
              }}
              placement="bottomRight"
            >
              <Button icon={<UserOutlined />}>账号</Button>
            </Dropdown>
          </Space>
        </Layout.Header>
        <Layout.Content className="admin-content">
          <Outlet />
        </Layout.Content>
      </Layout>
    </Layout>
  )
}

function resolveSelectedKey(pathname: string) {
  if (pathname.startsWith('/admin/orders')) return '/admin/orders'
  if (pathname.startsWith('/admin/tasks')) return '/admin/tasks'
  if (pathname === '/admin/platform-shops') return '/admin/platform-shops'
  return pathname
}

function roleLabel(role: string) {
  if (role === 'admin') return '管理员'
  if (role === 'operator') return '普通运营'
  return '客服'
}