import { User, DatabaseInterface, AuthenticationService } from '@accounts/types';
import { AccountsServer, ServerHooks } from '@accounts/server';
import { OAuthOptions } from './types/oauth-options';
import { OAuthUser } from './types/oauth-user';

const getRegistrationPayloadDefault = async (oauthUser: OAuthUser) => {
  return {
    email: oauthUser.email,
  };
};

export class AccountsOauth implements AuthenticationService {
  public server!: AccountsServer;
  public serviceName = 'oauth';
  private db!: DatabaseInterface;
  private options: OAuthOptions;

  constructor(options: OAuthOptions) {
    this.options = options;
  }

  public setStore(store: DatabaseInterface) {
    this.db = store;
  }

  public async authenticate(params: any): Promise<User | null> {
    if (!params.provider || !this.options[params.provider]) {
      throw new Error('Invalid provider');
    }

    const userProvider = this.options[params.provider];

    if (typeof userProvider.authenticate !== 'function') {
      throw new Error('Invalid provider');
    }

    const oauthUser = await userProvider.authenticate(params);
    let user = await this.db.findUserByServiceId(params.provider, oauthUser.id);

    if (!user && oauthUser.email) {
      user = await this.db.findUserByEmail(oauthUser.email);
    }

    if (!user) {
      try {
        const userData = await (
          userProvider.getRegistrationPayload || getRegistrationPayloadDefault
        )(oauthUser);

        const userId = await this.db.createUser(userData);

        user = (await this.db.findUserById(userId)) as User;

        if (this.server) {
          await this.server.getHooks().emit(ServerHooks.CreateUserSuccess, user);
        }
      } catch (e) {
        if (this.server) {
          await this.server.getHooks().emit(ServerHooks.CreateUserError, user);
        }

        throw e;
      }
    }

    await this.db.setService(user.id, params.provider, oauthUser);

    return user;
  }

  public async unlink(userId: string, provider: string) {
    if (!provider || !this.options[provider]) {
      throw new Error('Invalid provider');
    }

    await this.db.setService(userId, provider, null as any);
  }
}