cothema / ionic-universal-firebase-login

import { AngularFireAuth } from "@angular/fire/auth";

import {

    AngularFirestore,

    AngularFirestoreDocument,

} from "@angular/fire/firestore";

import * as firebase from "firebase";

import { Observable, of } from "rxjs";

import { switchMap } from "rxjs/operators";

import { UniFirebaseLoginConfig } from "../config/uni-firebase-login-config";

import { StorageUserModel } from "../model/storage-user-model";

import { UserModel } from "../model/user-model";

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

@Injectable({

    providedIn: "root",

})

export class FirestoreStorage<User extends UserModel = UserModel>

    implements IStorageProvider<User> {

    public constructor(

        protected angularFireAuth: AngularFireAuth,

        protected angularFirestore: AngularFirestore,

        protected config: UniFirebaseLoginConfig,

    ) {}

    public async updateStoredDataByUser(user: User): Promise<void> {

        if (user.uid) {

            const userRef = this.getUserRef(user.uid);

            const data = this.config.storageUserFactoryFunc(

                this.config.mapUserToStorageFunc(user),

            );

            await userRef.set(JSON.parse(JSON.stringify(data)), {

                merge: true,

            });

        } else {

            throw new Error("Firebase user has no UID.");

        }

    }

    public getUserRef(

        userUid: string,

    ): AngularFirestoreDocument<StorageUserModel> {

        if (this.config.storageUserTable === null) {

            throw new Error("userTable is not specified!");

        }

        return this.angularFirestore

            .collection(this.config.storageUserTable)

            .doc(userUid);

    }

    }

    public async fetchUser(): Promise<User | null> {

        return this.subscribeUser().toPromise();

    }

    public subscribeUser(): Observable<User | null> {

        // Get the auth state, then fetch the Firestore user document or return null

        return this.angularFireAuth.authState.pipe(

            switchMap((user: any) => {

                if (user) {

                    // User is logged in

                    return this.angularFirestore

                        .doc<StorageUserModel>(

                            `${this.config.storageUserTable}/${user.uid}`,

                        )

                        .valueChanges()

                        .pipe(

                            switchMap((userFirebase: any) => {

                                return new Observable(subscriber => {

                                    subscriber.next(

                                        Object.assign<User, any>(

                                            this.getNewUser(),

                                            userFirebase,

                                        ),

                                    );

                                    subscriber.complete();

                                });

                            }),

                        );

                }

                // Logged out

                return of(null);

            }),

        ) as Observable<User | null>;

    }

    /**

     * Override this method if you want to use custom model class

     */

    protected getNewUser(): User {

        return this.config.userFactoryFunc() as User;

    }

}