ghostfolio/apps/api/src/services/cryptocurrency/cryptocurrency.service.ts

import { DEFAULT_CURRENCY } from '@ghostfolio/common/config';

import { Injectable } from '@nestjs/common';

const cryptocurrencies = require('../../assets/cryptocurrencies/cryptocurrencies.json');
const customCryptocurrencies = require('../../assets/cryptocurrencies/custom.json');

@Injectable()
export class CryptocurrencyService {
  private combinedCryptocurrencies: string[];

  public isCryptocurrency(aSymbol = '') {
    const cryptocurrencySymbol = aSymbol.substring(0, aSymbol.length - 3);

    return (
      aSymbol.endsWith(DEFAULT_CURRENCY) &&
      this.getCryptocurrencies().includes(cryptocurrencySymbol)
    );
  }

  private getCryptocurrencies() {
    if (!this.combinedCryptocurrencies) {
      this.combinedCryptocurrencies = [
        ...Object.keys(cryptocurrencies),
        ...Object.keys(customCryptocurrencies)
      ];
    }

    return this.combinedCryptocurrencies;
  }
}