cothema / ionic-universal-firebase-login

import { Injectable } from "@angular/core";

import { Cacheable } from "ngx-cacheable";

import { from, Observable } from "rxjs";

import { UserModel } from "..";

import { UserFactory } from "../factories/user-factory";

import { FirebaseStorage } from "./firebase-storage";

import { IStorageProvider } from "./i-storage-provider";

import { IStorageProviderOptions } from "./i-storage-provider-options";

import { InMemoryStorage } from "./in-memory-storage.service";

@Injectable({

    providedIn: "root",

})

export class AuthStorageProvider<User extends UserModel = UserModel> {

    public options: IStorageProviderOptions = {

        storage: false,

        userTable: "users",

    };

    public constructor(

        public userFactory: UserFactory,

        private firebaseStorage: FirebaseStorage<User>,

        private inMemoryStorage: InMemoryStorage,

    ) {}

    /**

     * Get user from cache if possible or from a storage

     */

    @Cacheable()

    public getUser(): Observable<User | unknown | null> {

        const storageProvider = this.getProvider();

        if (storageProvider !== null) {

            return from(storageProvider.fetchUser());

        }

        throw new Error("No storage provider found.");

    }

    public getProvider() {

        return this.getProviderById(this.options.storage);

    }

    protected getProviderById(

        providerId: false | "firestore",

    ): IStorageProvider<User> {

        let provider;

        switch (providerId) {

            case "firestore":

                provider = this.firebaseStorage;

                provider.options.userTable = this.options.userTable;

                break;

            case false:

                provider = this.inMemoryStorage;

                break;

        }

        if (provider !== undefined) {

            return provider;

        }

        throw new Error(`Provider ${providerId} not supported.`);

    }

}