import { ConfigService } from '@nestjs/config';
import { ES256 } from '@sd-jwt/crypto-nodejs';
import { ED25519 } from './ed25519';
import { CryptoImplementation } from './crypto-implementation';
import { Injectable } from '@nestjs/common';

export type CryptoType = 'ES256' | 'Ed25519';

@Injectable()
export class CryptoImplementationService {
    constructor(private configServie: ConfigService) {}

    /**
     * Return the algorithm that is used for the crypto operations like signing.
     * @returns
     */
    getAlg(): CryptoType {
        return this.configServie.get('CRYPTO_ALG') as CryptoType;
    }

    getCrypto(
        alg = this.configServie.get<string>('CRYPTO_ALG'),
    ): CryptoImplementation {
        switch (alg) {
            case 'Ed25519':
                return ED25519;
            case 'ES256':
                return ES256;
            default:
                throw new Error(`Unsupported algorithm ${alg}`);
        }
    }
}