import { Observable, throwError } from 'rxjs';
import { catchError, map } from 'rxjs/operators';
import { Inject, Injectable } from '@angular/core';
import { HttpClient, HttpEvent, HttpHandler, HttpInterceptor, HttpRequest } from '@angular/common/http';

import { colorsEnum } from '../../../shared';
import { ToastService, toastPositionEnum } from '../../../elements';
import { Data } from '@angular/router';

@Injectable()
export class HttpClientRequestService implements HttpInterceptor {
    private isRefreshToken: boolean;

    constructor(
        private readonly http: HttpClient,
        private readonly toastService: ToastService,
        @Inject('OAuthModel') private readonly oAuthModel,
        @Inject('Environment') private readonly environment,
    ) {}

    public intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
        const { url } = request;

        return next.handle(request.clone({
            setHeaders: {
                Authorization: this.isRefreshToken ? '' : `Bearer ${ this.oAuthModel.data.token }`,
            },
            url: `${ this.environment.api }${ url }`,
        })).pipe(
            map((event: HttpEvent<any>) => event),
            catchError((event) => {
                this.checkError(event, request);

                return throwError(event.error);
            })
        );
    }

    private checkError(error, request) {
        if (error.status >= 500) {
            this.handleError500(error);
        } else if (error.status === 403) {
            this.isRefreshToken = true;
            this.handleRefreshToken(error, request);
        }
    }

    private handleError500({ error }): void {
        this.toastService.open({
            message: error.message,
            type: colorsEnum.error,
            duration: 30000000,
            dismissible: true,
            position: toastPositionEnum.topCenter
        });
    }

    private handleRefreshToken(event, request): void {
        this.http.post(this.environment.refreshPath, {
            token: this.oAuthModel.data.token,
            refreshToken: this.oAuthModel.data.refreshToken,
        }).toPromise()
            .then((data: Data) => {
                this.oAuthModel.data = data;
                this.isRefreshToken = false;
            }).catch(() => {
                this.oAuthModel.data = {};
                this.isRefreshToken = false;
            });
    }
}