common-ui/src/lib/listing/services/listing.service.ts
2021-12-02 01:51:53 +02:00

128 lines
4.6 KiB
TypeScript

import { Injectable } from '@angular/core';
import { BehaviorSubject, combineLatest, Observable } from 'rxjs';
import { map, tap } from 'rxjs/operators';
import { FilterService, getFilteredEntities } from '../../filtering';
import { SearchService } from '../../search';
import { IListable } from '../models';
import { EntitiesService } from './entities.service';
import { any, getLength, shareDistinctLast, shareLast } from '../../utils';
@Injectable()
export class ListingService<E extends IListable> {
readonly displayed$: Observable<E[]>;
readonly displayedLength$: Observable<number>;
readonly areAllSelected$: Observable<boolean>;
readonly areSomeSelected$: Observable<boolean>;
readonly notAllSelected$: Observable<boolean>;
readonly selected$: Observable<(string | number)[]>;
readonly selectedEntities$: Observable<E[]>;
readonly selectedLength$: Observable<number>;
private _displayed: E[] = [];
private readonly _selected$ = new BehaviorSubject<(string | number)[]>([]);
constructor(
private readonly _filterService: FilterService,
private readonly _searchService: SearchService<E>,
private readonly _entitiesService: EntitiesService<E>,
) {
this.displayed$ = this._getDisplayed$;
this.displayedLength$ = this.displayed$.pipe(getLength, shareDistinctLast());
this.selected$ = this._selected$.asObservable().pipe(shareDistinctLast());
this.selectedEntities$ = this._selected$.asObservable().pipe(
map(() => this.selected),
shareLast(),
);
this.selectedLength$ = this._selected$.pipe(getLength, shareDistinctLast());
this.areAllSelected$ = this._areAllSelected$;
this.areSomeSelected$ = this._areSomeSelected$;
this.notAllSelected$ = this._notAllSelected$;
}
get selected(): E[] {
const selectedIds = this.selectedIds;
return this._entitiesService.all.filter(a => selectedIds.includes(a.id));
}
get selectedIds(): (string | number)[] {
return this._selected$.getValue();
}
private get _getDisplayed$(): Observable<E[]> {
const { filterGroups$ } = this._filterService;
const { valueChanges$ } = this._searchService;
return combineLatest([this._entitiesService.all$, filterGroups$, valueChanges$]).pipe(
map(([entities, filterGroups]) => getFilteredEntities(entities, filterGroups)),
map(entities => this._searchService.searchIn(entities)),
tap(displayed => {
this._displayed = displayed;
this._updateSelection();
}),
shareLast(),
);
}
private get _areAllSelected$(): Observable<boolean> {
return combineLatest([this.displayedLength$, this.selectedLength$]).pipe(
map(([displayedLength, selectedLength]) => !!displayedLength && displayedLength === selectedLength),
shareDistinctLast(),
);
}
private get _areSomeSelected$(): Observable<boolean> {
return this.selectedLength$.pipe(
map(length => !!length),
shareDistinctLast(),
);
}
private get _notAllSelected$(): Observable<boolean> {
return combineLatest([this.areAllSelected$, this.areSomeSelected$]).pipe(
map(([allAreSelected, someAreSelected]) => !allAreSelected && someAreSelected),
shareDistinctLast(),
);
}
private get _allSelected() {
return this._displayed.length !== 0 && this._displayed.length === this.selected.length;
}
setSelected(newEntities: E[]): void {
const selectedIds = newEntities.map(e => e.id);
this._selected$.next(selectedIds);
}
isSelected(entity: E): boolean {
return this.selectedIds.indexOf(entity.id) !== -1;
}
isSelected$(entity: E): Observable<boolean> {
return this._selected$.pipe(
any(selectedId => selectedId === entity.id),
shareLast(),
);
}
selectAll(): void {
if (this._allSelected) {
return this.setSelected([]);
}
this.setSelected(this._displayed);
}
select(entity: E): void {
const currentEntityIdx = this.selected.indexOf(entity);
if (currentEntityIdx === -1) {
return this.setSelected([...this.selected, entity]);
}
this.setSelected(this.selected.filter((el, idx) => idx !== currentEntityIdx));
}
private _updateSelection(): void {
const items = this._displayed.filter(item => this.selected.includes(item));
this.setSelected(items);
}
}