import { Injectable, Injector, ComponentFactoryResolver, ComponentRef } from '@angular/core';
import { ModalComponent } from './modal.component';
import { ModalOptions } from './modal-options.model';
import { RebirthNGConfig } from '../rebirth-ng.config';
import { tap, catchError } from 'rxjs/operators';
import { throwError, Observable } from 'rxjs';

@Injectable({ providedIn: 'root' })
export class ModalService {

  private instances = [];

  constructor(private rebirthNGConfig: RebirthNGConfig, private componentFactoryResolver: ComponentFactoryResolver,
              private injector: Injector) {
  }


  open<T>(options: ModalOptions): Observable<T> {
    const rootContainer = options.rootContainer || this.rebirthNGConfig.rootContainer;
    if (!rootContainer) {
      throw new Error('Should setup ViewContainerRef on modal options or rebirth config service!');
    }
    if (options.animation === undefined || options.animation === null) {
      options.animation = this.rebirthNGConfig.modal.animation;
    }
    const componentFactory = this.componentFactoryResolver.resolveComponentFactory(ModalComponent);
    const injector = options.injector || this.injector;
    const modalRef = <ComponentRef<ModalComponent>>rootContainer
      .createComponent(componentFactory, rootContainer.length, injector);
    this.instances.push(modalRef);
    const instance: ModalComponent = modalRef.instance;
    const dismissResult = instance.addContent(options, this.instances.length)
      .pipe(
        tap(() => this.close(modalRef)),
        catchError(error => {
          this.close(modalRef);
          return throwError(error);
        })
      );
    instance.open();
    return dismissResult as any;
  }

  closeAll(): void {
    this.instances.forEach(modalRef => this.close(modalRef));
  }

  private close(modalRef: ComponentRef<ModalComponent>): void {
    this.instances.splice(this.instances.indexOf(modalRef), 1);
    const subscriber = modalRef.instance.close()
      .subscribe(_ => {
        subscriber.unsubscribe();
        if (!this.instances.length) {
          modalRef.instance.cleanup();
        }
        modalRef.destroy();
      });
  }
}