///
/// Copyright © 2016-2019 The Thingsboard Authors
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///

import { Component, OnDestroy, OnInit } from '@angular/core';
import { BehaviorSubject, Subject } from 'rxjs';
import { BreadCrumb } from './breadcrumb';
import { ActivatedRoute, ActivatedRouteSnapshot, NavigationEnd, Router } from '@angular/router';
import { distinctUntilChanged, filter, map } from 'rxjs/operators';

@Component({
  selector: '[tb-breadcrumb]',
  templateUrl: './breadcrumb.component.html',
  styleUrls: ['./breadcrumb.component.scss']
})
export class BreadcrumbComponent implements OnInit, OnDestroy {

  breadcrumbs$: Subject<Array<BreadCrumb>> = new BehaviorSubject<Array<BreadCrumb>>(this.buildBreadCrumbs(this.activatedRoute.snapshot));

  routerEventsSubscription = this.router.events.pipe(
    filter((event) => event instanceof NavigationEnd ),
    distinctUntilChanged(),
    map( () => this.buildBreadCrumbs(this.activatedRoute.snapshot) )
  ).subscribe(breadcrumns => this.breadcrumbs$.next(breadcrumns) );

  lastBreadcrumb$ = this.breadcrumbs$.pipe(
    map( breadcrumbs => breadcrumbs[breadcrumbs.length - 1])
  );

  constructor(private router: Router,
              private activatedRoute: ActivatedRoute) {
  }

  ngOnInit(): void {
  }

  ngOnDestroy(): void {
    if (this.routerEventsSubscription) {
      this.routerEventsSubscription.unsubscribe();
    }
  }


  buildBreadCrumbs(route: ActivatedRouteSnapshot, breadcrumbs: Array<BreadCrumb> = []): Array<BreadCrumb> {
    let newBreadcrumbs = breadcrumbs;
    if (route.routeConfig && route.routeConfig.data) {
      const breadcrumbData = route.routeConfig.data.breadcrumb;
      if (breadcrumbData && !breadcrumbData.skip) {
        const label = breadcrumbData.label || 'home.home';
        const icon = breadcrumbData.icon || 'home';
        const isMdiIcon = icon.startsWith('mdi:');
        const link = [ '/' + route.url.join('') ];
        const queryParams = route.queryParams;
        const breadcrumb = {
          label,
          icon,
          isMdiIcon,
          link,
          queryParams
        };
        newBreadcrumbs = [...breadcrumbs, breadcrumb];
      }
    }
    if (route.firstChild) {
      return this.buildBreadCrumbs(route.firstChild, newBreadcrumbs);
    }
    return newBreadcrumbs;
  }

}