import * as plugins from './dnsly.plugins.js';

export type TDnsProvider = 'google' | 'cloudflare';

export const makeNodeProcessUseDnsProvider = (providerArg: TDnsProvider) => {
  switch (providerArg) {
    case 'cloudflare':
      plugins.dns.setServers([
        '1.1.1.1',
        '1.0.0.1',
        '[2606:4700:4700::1111]',
        '[2606:4700:4700::1001]',
      ]);
      break;
    case 'google':
      plugins.dns.setServers([
        '8.8.8.8',
        '8.8.4.4',
        '[2001:4860:4860::8888]',
        '[2606:4700:4700::1001]',
      ]);
  }
};

export interface ISmartDnsConstructorOptions {}

export interface IDnsJsonResponse {
  Status: number;
  TC: boolean;
  RD: boolean;
  RA: boolean;
  AD: boolean;
  CD: boolean;
  Question: Array<{ name: string; type: number }>;
  Answer: Array<{ name: string; type: number; TTL: number; data: string }>;
  Additional: [];
  Comment: string;
}

/**
 * class dnsly offers methods for working with dns from a dns provider like Google DNS
 */
export class Smartdns {
  public dnsServerIp: string;
  public dnsServerPort: number;

  public dnsTypeMap: { [key: string]: number } = {
    A: 1,
    AAAA: 28,
    CNAME: 5,
    MX: 15,
    TXT: 16,
  };

  /**
   * constructor for class dnsly
   */
  constructor(optionsArg: ISmartDnsConstructorOptions) {}

  /**
   * check a dns record until it has propagated to Google DNS
   * should be considerably fast
   * @param recordNameArg
   * @param recordTypeArg
   * @param expectedValue
   */
  public async checkUntilAvailable(
    recordNameArg: string,
    recordTypeArg: plugins.tsclass.network.TDnsRecordType,
    expectedValue: string,
    cyclesArg: number = 50,
    intervalArg: number = 500
  ) {
    let runCycles = 0;
    const doCheck = async () => {
      if (runCycles < cyclesArg) {
        runCycles++;
        try {
          let myRecordArray: plugins.tsclass.network.IDnsRecord[];
          if (runCycles % 2 === 0 || !plugins.dns) {
            myRecordArray = await this.getRecords(recordNameArg, recordTypeArg, 0);
          } else {
            myRecordArray = await this.getRecordWithNodeDNS(recordNameArg, recordTypeArg);
          }
          const myRecord = myRecordArray[0].value;
          if (myRecord === expectedValue) {
            console.log(
              `smartdns: .checkUntilAvailable() verified that wanted >>>${recordTypeArg}<<< record exists for >>>${recordNameArg}<<< with value >>>${expectedValue}<<<`
            );
            return true;
          } else {
            await plugins.smartdelay.delayFor(intervalArg);
            return await doCheck();
          }
        } catch (err) {
          // console.log(err);
          await plugins.smartdelay.delayFor(intervalArg);
          return await doCheck();
        }
      } else {
        console.log(
          `smartdns: .checkUntilAvailable() failed permanently for ${recordNameArg} with value ${recordTypeArg} - ${expectedValue}...`
        );
        return false;
      }
    };
    return await doCheck();
  }

  /**
   * get A Dns Record
   */
  public async getRecordsA(recordNameArg: string): Promise<plugins.tsclass.network.IDnsRecord[]> {
    return await this.getRecords(recordNameArg, 'A');
  }

  /**
   * get AAAA Record
   */
  public async getRecordsAAAA(recordNameArg: string) {
    return await this.getRecords(recordNameArg, 'AAAA');
  }

  /**
   * gets a txt record
   */
  public async getRecordsTxt(recordNameArg: string): Promise<plugins.tsclass.network.IDnsRecord[]> {
    return await this.getRecords(recordNameArg, 'TXT');
  }

  public async getRecords(
    recordNameArg: string,
    recordTypeArg: plugins.tsclass.network.TDnsRecordType,
    retriesCounterArg = 20
  ): Promise<plugins.tsclass.network.IDnsRecord[]> {
    const requestUrl = `https://cloudflare-dns.com/dns-query?name=${recordNameArg}&type=${recordTypeArg}&do=1`;
    const returnArray: plugins.tsclass.network.IDnsRecord[] = [];
    const getResponseBody = async (counterArg = 0): Promise<IDnsJsonResponse> => {
      const response = await plugins.smartrequest.request(requestUrl, {
        method: 'GET',
        headers: {
          accept: 'application/dns-json',
        },
      });
      const responseBody: IDnsJsonResponse = response.body;
      if (responseBody?.Status !== 0 && counterArg < retriesCounterArg) {
        await plugins.smartdelay.delayFor(500);
        return getResponseBody(counterArg++);
      } else {
        return responseBody;
      }
    };
    const responseBody = await getResponseBody();
    if (!responseBody.Answer || !typeof responseBody.Answer[Symbol.iterator]) {
      return returnArray;
    }
    for (const dnsEntry of responseBody.Answer) {
      if (dnsEntry.data.startsWith('"') && dnsEntry.data.endsWith('"')) {
        dnsEntry.data = dnsEntry.data.replace(/^"(.*)"$/, '$1');
      }
      if (dnsEntry.name.endsWith('.')) {
        dnsEntry.name = dnsEntry.name.substring(0, dnsEntry.name.length - 1);
      }
      returnArray.push({
        name: dnsEntry.name,
        type: this.convertDnsTypeNumberToTypeName(dnsEntry.type),
        dnsSecEnabled: responseBody.AD,
        value: dnsEntry.data,
      });
    }
    // console.log(responseBody);
    return returnArray;
  }

  /**
   * gets a record using nodejs dns resolver
   */
  public async getRecordWithNodeDNS(
    recordNameArg: string,
    recordTypeArg: plugins.tsclass.network.TDnsRecordType
  ): Promise<plugins.tsclass.network.IDnsRecord[]> {
    const done = plugins.smartpromise.defer<plugins.tsclass.network.IDnsRecord[]>();
    plugins.dns.resolve(recordNameArg, recordTypeArg, (err, recordsArg) => {
      if (err) {
        done.reject(err);
        return;
      }
      const returnArray: plugins.tsclass.network.IDnsRecord[] = [];
      for (const recordKey in recordsArg) {
        returnArray.push({
          name: recordNameArg,
          value: recordsArg[recordKey][0],
          type: recordTypeArg,
          dnsSecEnabled: false,
        });
      }
      done.resolve(returnArray);
    });
    return done.promise;
  }

  public async getNameServers(domainNameArg: string): Promise<string[]> {
    const done = plugins.smartpromise.defer<string[]>();
    plugins.dns.resolveNs(domainNameArg, (err, result) => {
      if (!err) {
        done.resolve(result);
      } else {
        console.log(err);
        done.reject(err);
      }
    });
    return await done.promise;
  }

  public convertDnsTypeNameToTypeNumber(dnsTypeNameArg: string): number {
    return this.dnsTypeMap[dnsTypeNameArg];
  }

  public convertDnsTypeNumberToTypeName(
    dnsTypeNumberArg: number
  ): plugins.tsclass.network.TDnsRecordType {
    for (const key in this.dnsTypeMap) {
      if (this.dnsTypeMap[key] === dnsTypeNumberArg) {
        return key as plugins.tsclass.network.TDnsRecordType;
      }
    }
    return null;
  }
}