import { Buffer } from 'buffer';
import zlib from 'zlib';
import { STATUS_LIST } from '../config.js';
import { RevocationStatusList } from './revocationStatusList.js';
import InvalidCredentialIndexException from './exceptions/invalidCredentialIndexException.js';
import { BitSet } from 'bitset';

export class RevocationStatusListBitSet implements RevocationStatusList {
  private encodedList: BitSet;

  constructor() {
    this.encodedList = new BitSet();
  }

  encoded(): string {
    const input = Buffer.from(
      this.encodedList
        .toString()
        .padStart(STATUS_LIST.MAX_CREDENTIAL_ID + 1, '0'),
    );
    const compressedData = zlib.deflateSync(input);
    return Buffer.from(compressedData).toString('base64');
  }

  static fromEncoded(encodedList: string): RevocationStatusListBitSet {
    const decodedFromBase64 = Buffer.from(encodedList, 'base64');
    const uncompressedData = zlib.inflateSync(decodedFromBase64).toString();
    const revocationList = new RevocationStatusListBitSet();
    revocationList.encodedList = new BitSet(uncompressedData);
    return revocationList;
  }

  revokeCredential(credentialId: number): void {
    this.checkCredentialId(credentialId);
    this.encodedList.set(credentialId, 1);
  }

  checkCredentialId(credentialId: number): void {
    if (credentialId > STATUS_LIST.MAX_CREDENTIAL_ID || credentialId < 1)
      throw new InvalidCredentialIndexException(credentialId.toString());
  }

  isRevoked(credentialId: number): boolean {
    this.checkCredentialId(credentialId);
    return this.encodedList.get(credentialId) === 1;
  }
}