Asymmetrik/ngx-starter

import { Directive, input } from '@angular/core';

import { SortChange } from '../../sorting.model';
import { AsyTableDataSource } from '../asy-table-data-source';

/** Interface for a directive that holds sorting state consumed by `AsySortHeader`. */
export interface AsySortable {
    /** The id of the column being sorted. */
    id: string;
}

@Directive({
    selector: '[asySort]',
    exportAs: 'asySort',
    host: { class: 'asy-sort' },
    standalone: true
})
export class AsySortDirective<T> {
    readonly dataSource = input.required<AsyTableDataSource<T>>();

    /** Collection of all registered sortables that this directive manages. */
    sortables = new Map<string, AsySortable>();

    /**
     * Register function to be used by the contained AsySortables. Adds the AsySortable to the
     * collection of AsySortables.
     */
    register(sortable: AsySortable): void {
        if (!sortable.id) {
            throw Error(`AsySortHeaderComponent must be provided with a unique id.`);
        }

        if (this.sortables.has(sortable.id)) {
            throw Error(`Cannot have two AsySortables with the same id (${sortable.id}).`);
        }

        this.sortables.set(sortable.id, sortable);
    }

    /**
     * Unregister function to be used by the contained AsySortables. Removes the AsySortable from the
     * collection of contained AsySortables.
     */
    deregister(sortable: AsySortable): void {
        this.sortables.delete(sortable.id);
    }

    sort(sortChange: SortChange): void {
        this.dataSource().sort(sortChange);
    }
}