import { Alert, Card, Space, Table, Tag, Typography } from 'antd'
import type { ColumnsType } from 'antd/es/table'
import { useQuery } from '@tanstack/react-query'
import { useTranslation } from 'react-i18next'

import apiClient, { isEnvelope } from '../../api/client'

interface AutoRule {
  Proto: string
  Port: number
  DstIP?: string
  Comment: string
}

async function listAutoRules(): Promise<AutoRule[]> {
  try {
    const r = await apiClient.get('/firewall/auto-rules')
    if (!isEnvelope(r.data)) return []
    return (r.data.data as { rules?: AutoRule[] }).rules ?? []
  } catch { return [] }
}

// SystemRulesCard documents the baseline nftables ruleset that
// EdgeGuard installs unconditionally — anti-lockout, stateful
// session handling, public ingress, cluster mTLS. These rules sit
// in the kernel ruleset BEFORE any operator-defined rule and can
// not be overruled from the UI (they live in the renderer's nft
// template). Showing them here closes the "wait, where does the
// implicit drop come from?"-gap.

interface SystemRule {
  key: string
  chain: string
  match: string
  action: string
  note?: string
}

const ROWS: SystemRule[] = [
  { key: 'a1', chain: 'input', match: 'tcp dport 22 (rate-limit 10/min)',           action: 'accept', note: 'anti-lockout: SSH' },
  { key: 'a2', chain: 'input', match: 'tcp dport 443',                               action: 'accept', note: 'anti-lockout: HAProxy public HTTPS' },
  { key: 'a2u',chain: 'input', match: 'udp dport 443',                               action: 'accept', note: 'anti-lockout: HAProxy HTTP/3 (QUIC)' },
  { key: 'a3', chain: 'input', match: 'tcp dport 3443',                              action: 'accept', note: 'anti-lockout: Management-UI (admin HTTPS)' },
  { key: 'b1', chain: 'input', match: 'ct state established,related',                action: 'accept', note: 'stateful baseline' },
  { key: 'b2', chain: 'input', match: 'ct state invalid',                            action: 'drop',   note: 'stateful baseline' },
  { key: 'b3', chain: 'input', match: 'iif lo',                                      action: 'accept', note: 'loopback' },
  { key: 'c1', chain: 'input', match: 'icmp/icmpv6 (echo, dest-unreach, time-exc.)', action: 'accept', note: 'PMTUD + diag' },
  { key: 'd1', chain: 'input', match: 'tcp dport 80',                                action: 'accept', note: 'HAProxy ACME + redirect' },
  { key: 'e1', chain: 'input', match: 'tcp dport 8443 ip saddr @peer_ipv4/v6',       action: 'accept', note: 'cluster mTLS (peers only)' },
]

const ACTION_COLORS: Record<string, string> = {
  accept: 'green', drop: 'red', reject: 'orange',
}

export default function SystemRulesCard() {
  const { t } = useTranslation()
  const { data: autoRules } = useQuery({ queryKey: ['fw', 'auto-rules'], queryFn: listAutoRules, refetchInterval: 30_000 })

  // Static system rules + dynamic auto-rules zu einer Liste mergen.
  const dynamic: SystemRule[] = (autoRules ?? []).map((r, i) => ({
    key: `auto-${i}`,
    chain: 'input',
    match: `${r.DstIP ? `ip daddr ${r.DstIP} ` : ''}${r.Proto} dport ${r.Port}`,
    action: 'accept',
    note: `auto: ${r.Comment}`,
  }))
  const allRows = [...ROWS, ...dynamic]

  const cols: ColumnsType<SystemRule> = [
    { title: t('fw.sys.chain'),  dataIndex: 'chain',  key: 'chain',  width: 80,  render: (s: string) => <Tag>{s}</Tag> },
    { title: t('fw.sys.match'),  dataIndex: 'match',  key: 'match',  render: (s: string) => <code>{s}</code> },
    {
      title: t('fw.sys.action'), dataIndex: 'action', key: 'action', width: 90,
      render: (a: string) => <Tag color={ACTION_COLORS[a] ?? 'default'}>{a.toUpperCase()}</Tag>,
    },
    { title: t('fw.sys.note'),   dataIndex: 'note',   key: 'note',   render: (v?: string) => v ? <Typography.Text type="secondary">{v}</Typography.Text> : '—' },
  ]
  return (
    <Card size="small" title={t('fw.sys.title')} className="mb-12">
      <Alert
        type="info"
        showIcon
        className="mb-12"
        message={
          <Space direction="vertical" size={2}>
            <span><b>{t('fw.sys.policy')}:</b> {t('fw.sys.policyValue')}</span>
            <span><b>{t('fw.sys.order')}:</b> {t('fw.sys.orderValue')}</span>
            <span><b>{t('fw.sys.lockout')}:</b> {t('fw.sys.lockoutValue')}</span>
          </Space>
        }
      />
      <Table
        size="small"
        rowKey="key"
        columns={cols}
        dataSource={allRows}
        pagination={false}
      />
    </Card>
  )
}