import { soapRequest, type DigestAuthOptions } from "./digestAuth.js";

const SERVICE_TYPE = "urn:dslforum-org:service:Hosts:1";

function actionEnvelope(action: string, params: Record<string, string | number> = {}): string {
  const args = Object.entries(params)
    .map(([key, value]) => `<${key}>${value}</${key}>`)
    .join("");

  return (
    `<?xml version="1.0" encoding="utf-8"?>` +
    `<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" ` +
    `s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">` +
    `<s:Body><u:${action} xmlns:u="${SERVICE_TYPE}">${args}</u:${action}></s:Body>` +
    `</s:Envelope>`
  );
}

function extractTag(xml: string, tag: string): string | null {
  const match = xml.match(new RegExp(`<${tag}>([^<]*)</${tag}>`, "i"));
  return match ? match[1] : null;
}

export interface FritzBoxHost {
  ip: string;
  mac: string | null;
  hostname: string;
  online: boolean;
}

/**
 * Liest die vollständige Geräteliste der FritzBox über die TR-064-Aktionen
 * GetHostNumberOfEntries + GetGenericHostEntry (urn:dslforum-org:service:Hosts:1).
 */
export async function fetchFritzBoxHosts(options: DigestAuthOptions): Promise<FritzBoxHost[]> {
  const countXml = await soapRequest(
    options,
    `${SERVICE_TYPE}#GetHostNumberOfEntries`,
    actionEnvelope("GetHostNumberOfEntries")
  );
  const countStr = extractTag(countXml, "NewHostNumberOfEntries");
  const count = countStr ? parseInt(countStr, 10) : 0;

  const hosts: FritzBoxHost[] = [];

  for (let index = 0; index < count; index++) {
    const entryXml = await soapRequest(
      options,
      `${SERVICE_TYPE}#GetGenericHostEntry`,
      actionEnvelope("GetGenericHostEntry", { NewIndex: index })
    );

    const ip = extractTag(entryXml, "NewIPAddress");
    const hostname = extractTag(entryXml, "NewHostName");
    if (!ip || !hostname) continue; // inaktive/unvollständige Einträge überspringen

    hosts.push({
      ip,
      mac: extractTag(entryXml, "NewMACAddress"),
      hostname,
      online: extractTag(entryXml, "NewActive") === "1",
    });
  }

  return hosts;
}