import { User, Utf8, JSONWebToken, Credential, BioSample } from '@digitalpersona/core';
import { IAuthService } from '@digitalpersona/services';
import { Finger, Fingers } from './data';
import { Authenticator } from '../../private';

/**
 * Fingerprint authentication API.
 * Fingerprints support both authentication and identification.
 */
export class FingerprintsAuth extends Authenticator
{
    /** Constructs a new fingerprint authentication API object.
     * @param authService - an {@link AuthService|authentication service client} connected to the server.
     */
    constructor(authService: IAuthService) {
        super(authService);
    }

    /** Reads a list of fingers currently enrolled by the user.
     * @param user - a user name
     * @returns a promise to return a list of enrolled fingers.
     * If no fingers are enrolled, an emty list will be returned.
     * May reject if the user is unknown or in case of an error.
     */
    public getEnrolledFingers(user: User): Promise<Fingers>
    {
        return this.authService
            .GetEnrollmentData(user, Credential.Fingerprints)
            .then(data =>
                (JSON.parse(Utf8.fromBase64Url(data)) as object[])
                .map(item => Finger.fromJson(item)),
            );
    }

    /** Authenticates the user using their fingerprint samples.
     * @param identity - a {@link User |username} or a JSON Web Token.
     * @param samples - a collection of biometric samples with fingerprint scans.
     * @returns a promise to return a JSON Web Token containing a claim (`crd`) showing the fact
     * a fingerprint was used.
     * Will reject if authentication fails.
     * @remarks
     * If the `identity` parameter is a user name, a new token will be created.
     * If the `identity` parameter is a JSON Web Token, an updated token will be returned.
     */
    public authenticate(identity: User|JSONWebToken, samples: BioSample[]): Promise<JSONWebToken> {
        return super._authenticate(identity, new Credential(Credential.Fingerprints, samples));
    }

    /** Identifies the user with their fingerprints.
     * @param samples - a collection of biometric samples with fingerprint scans.
     * @returns a promise to return a JSON Web Token containing a claim (`crd`) showing the fact
     * a fingerprint was used.
     * Will reject if identification fails.
     * @remarks
     * If the `identity` parameter is a user name, a new token will be created.
     * If the `identity` parameter is a JSON Web Token, an updated token will be returned.
     */
    public identify(samples: BioSample[]): Promise<JSONWebToken> {
        return super._identify(new Credential(Credential.Fingerprints, samples));
    }
}