import { execSync, spawnSync } from 'node:child_process';
import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';

import { CA_CERT, CERTS_DIR, HOST, SERVER_CERT, SERVER_KEY } from './config.mjs';

const SQL_CA_DIR = '/var/opt/mssql/security/ca-certificates';

export function certHosts(host) {
  const hosts = new Set([host, '127.0.0.1', 'localhost', 's3backup.local']);
  for (const iface of Object.values(os.networkInterfaces())) {
    for (const addr of iface || []) {
      if (addr.family === 'IPv4' && !addr.internal && !addr.address.startsWith('169.254.')) {
        hosts.add(addr.address);
      }
    }
  }
  return [...hosts].sort();
}

export function ensureCerts(host = HOST) {
  fs.mkdirSync(CERTS_DIR, { recursive: true });
  const hosts = certHosts(host);
  const marker = path.join(CERTS_DIR, 'hosts.txt');
  const hostList = hosts.join('\n');
  if (
    fs.existsSync(SERVER_CERT) &&
    fs.existsSync(SERVER_KEY) &&
    fs.existsSync(CA_CERT) &&
    fs.existsSync(marker) &&
    fs.readFileSync(marker, 'utf8') === hostList
  ) {
    return;
  }

  const cnf = `${CERTS_DIR}/openssl.cnf`;
  const altNames = hosts
    .map((h, i) => (/^\d+\./.test(h) ? `IP.${i + 1} = ${h}` : `DNS.${i + 1} = ${h}`))
    .join('\n');

  fs.writeFileSync(
    cnf,
    `[req]
distinguished_name = req_distinguished_name
x509_extensions = v3_req
prompt = no

[req_distinguished_name]
CN = ${host}

[v3_req]
subjectAltName = @alt_names
basicConstraints = CA:FALSE
keyUsage = digitalSignature, keyEncipherment
extendedKeyUsage = serverAuth

[alt_names]
${altNames}
`
  );

  execSync(
    `openssl req -x509 -newkey rsa:2048 -nodes -days 3650 \
      -keyout "${CERTS_DIR}/ca-key.pem" -out "${CA_CERT}" \
      -subj "/CN=JTL S3 Backup CA/O=JTL/C=DE"`,
    { stdio: 'pipe' }
  );

  execSync(
    `openssl req -newkey rsa:2048 -nodes \
      -keyout "${SERVER_KEY}" -out "${CERTS_DIR}/server.csr" \
      -config "${cnf}"`,
    { stdio: 'pipe' }
  );

  execSync(
    `openssl x509 -req -in "${CERTS_DIR}/server.csr" \
      -CA "${CA_CERT}" -CAkey "${CERTS_DIR}/ca-key.pem" -CAcreateserial \
      -out "${SERVER_CERT}" -days 3650 -extensions v3_req -extfile "${cnf}"`,
    { stdio: 'pipe' }
  );
  fs.writeFileSync(marker, hostList);
}

export function caTrustStatus(container = process.env.MSSQL_DOCKER_CONTAINER || 'mssql') {
  if (!fs.existsSync(CA_CERT)) {
    return { ok: false, inSync: false, restarted: false };
  }
  const localFp = execSync(`openssl x509 -in "${CA_CERT}" -noout -fingerprint -sha256`, {
    encoding: 'utf8',
  }).trim();
  const remoteFp = spawnSync(
    'docker',
    [
      'exec',
      container,
      'bash',
      '-lc',
      `test -f ${SQL_CA_DIR}/jtlsrv-s3-ca.pem && openssl x509 -in ${SQL_CA_DIR}/jtlsrv-s3-ca.pem -noout -fingerprint -sha256`,
    ],
    { encoding: 'utf8' }
  );
  const inSync = remoteFp.status === 0 && remoteFp.stdout.trim() === localFp;
  return { ok: remoteFp.status === 0, inSync, restarted: false };
}

export function installCaTrust(container = process.env.MSSQL_DOCKER_CONTAINER || 'mssql') {
  if (!fs.existsSync(CA_CERT)) {
    ensureCerts();
  }

  const localFp = execSync(`openssl x509 -in "${CA_CERT}" -noout -fingerprint -sha256`, {
    encoding: 'utf8',
  }).trim();
  const remoteFp = spawnSync(
    'docker',
    [
      'exec',
      container,
      'bash',
      '-lc',
      `test -f ${SQL_CA_DIR}/jtlsrv-s3-ca.pem && openssl x509 -in ${SQL_CA_DIR}/jtlsrv-s3-ca.pem -noout -fingerprint -sha256`,
    ],
    { encoding: 'utf8' }
  );
  if (remoteFp.status === 0 && remoteFp.stdout.trim() === localFp) {
    spawnSync('docker', [
      'exec',
      '-u',
      'root',
      container,
      'bash',
      '-lc',
      'grep -q s3backup.local /etc/hosts || echo "172.17.0.1 s3backup.local" >> /etc/hosts',
    ]);
    return { ok: true, restarted: false };
  }

  spawnSync('docker', ['exec', '-u', 'root', container, 'mkdir', '-p', SQL_CA_DIR], {
    stdio: 'pipe',
  });
  spawnSync('docker', [
    'exec',
    '-u',
    'root',
    container,
    'bash',
    '-lc',
    `rm -f ${SQL_CA_DIR}/*.pem ${SQL_CA_DIR}/*.crt`,
  ]);
  spawnSync('docker', [
    'exec',
    '-u',
    'root',
    container,
    'bash',
    '-lc',
    'grep -q s3backup.local /etc/hosts || echo "172.17.0.1 s3backup.local" >> /etc/hosts',
  ]);
  try {
    execSync('grep -q s3backup.local /etc/hosts || echo "172.17.0.1 s3backup.local" >> /etc/hosts', {
      stdio: 'pipe',
    });
  } catch {
    // optional on host
  }

  const copied = spawnSync(
    'docker',
    ['cp', CA_CERT, `${container}:${SQL_CA_DIR}/jtlsrv-s3-ca.pem`],
    { stdio: 'pipe' }
  );
  if (copied.status !== 0) {
    return { ok: false, restarted: false };
  }

  const perms = spawnSync(
    'docker',
    [
      'exec',
      '-u',
      'root',
      container,
      'bash',
      '-lc',
      `chown mssql:mssql ${SQL_CA_DIR}/jtlsrv-s3-ca.pem && chmod 644 ${SQL_CA_DIR}/jtlsrv-s3-ca.pem`,
    ],
    { stdio: 'pipe' }
  );
  if (perms.status !== 0) {
    return { ok: false, restarted: false };
  }

  const restarted = spawnSync('docker', ['restart', container], { stdio: 'pipe' });
  return { ok: true, restarted: restarted.status === 0 };
}