import { Injectable, inject } from '@angular/core';
import { BehaviorSubject, Observable } from 'rxjs';
import { copy } from '../../core/utils/ObjectUtils';
import { FormError } from '../../core/model/FormError';
import { UserRestService } from '../../core/rest-services/user/user.rest-service';
import { LoginRequest } from '../../core/rest-services/user/model/login.model';
import { AuthenticationService } from '../../core/service/authentication.service';
import { MatSnackBar } from '@angular/material/snack-bar';
import { Router } from '@angular/router';

export interface LoginState {
  request: LoginRequest;
  errors: FormError[];
}

const DEFAULT_STATE: LoginState = {
  request: {
    email: undefined,
    password: undefined,
  },
  errors: [],
};

@Injectable()
export class LoginService {
  private stateSubject = new BehaviorSubject<LoginState>(copy(DEFAULT_STATE));
  private userRestService = inject(UserRestService);
  private authenticationService = inject(AuthenticationService);
  private snackBar = inject(MatSnackBar);
  private router = inject(Router);

  get state$(): Observable<LoginState> {
    return this.stateSubject.asObservable();
  }

  private get state(): LoginState {
    return this.stateSubject.value;
  }

  private save(newState: LoginState): void {
    this.stateSubject.next(newState);
  }

  editEmail(newEmail: string): void {
    const state = this.state;

    state.request.email = newEmail;

    this.save(state);
  }

  editPassword(newPassword: string): void {
    const state = this.state;

    state.request.password = newPassword;

    this.save(state);
  }

  performLogin(): void {
    const state = this.state;

    // Check state is valid

    this.userRestService
      .login(state.request)
      .then((response) => {
        this.authenticationService.authenticate(response.accessToken, response.refreshToken);
        this.snackBar.open($localize`Authentication succeeded!`, $localize`Close`, { duration: 5000 });
        this.router.navigate(['/home']);
      })
      .catch((error) => {
        console.error(error);
        this.snackBar.open($localize`Authentication failed.`, $localize`Close`, { duration: 5000 });
      });
  }
}