import {inject, Injectable} 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;

    if (this.isStateValid(state)) {
      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.`, $localize`Close`, {duration: 5000});
        });
    } else {
      this.snackBar.open($localize`Please, fill the inputs before send.`, $localize`Close`, {duration: 5000});
    }
  }

  isStateValid(state: LoginState): boolean {
    return !!state.request.email?.trim().length && !!state.request.password?.length;
  }
}