import {
	Directive,
	EventEmitter,
	ElementRef,
	Input,
	HostListener,
	Output,
} from '@angular/core';

import { FileUploader } from './file-uploader.class';

@Directive({ selector: '[ngxFileSelect]' })
export class FileSelectDirective {
	@Input() public uploader: FileUploader;
	@Output() public onFileSelected: EventEmitter<File[]> = new EventEmitter<File[]>();

	protected element: ElementRef;

	public constructor(element: ElementRef) {
		this.element = element;
	}

	public getOptions(): any {
		return this.uploader.options;
	}

	public getFilters(): any {
		return {};
	}

	public isEmptyAfterSelection(): boolean {
		return !!this.element.nativeElement.attributes.multiple;
	}

	@HostListener('change')
	public onChange(): any {
		const files = this.element.nativeElement.files;
		const options = this.getOptions();
		const filters = this.getFilters();

		this.uploader.addToQueue(files, options, filters);
		this.onFileSelected.emit(files);

		if (this.isEmptyAfterSelection()) {
			this.element.nativeElement.value = '';
		}
	}
}