import { Injectable } from '@angular/core';
import { GenericService } from './generic.service';
import { Media } from '../data.types';
import { environment } from '../../environments/environment';
import { Observable, Subscriber, catchError, map, of } from 'rxjs';
import { HttpHeaders } from '@angular/common/http';

@Injectable()
export class FileService extends GenericService {

  upload(file: File): Observable<string> {
    const formData = new FormData();
    formData.append('file', file);

    return this.http
      .post(`${environment.apiBase}/file`, formData, {headers: new HttpHeaders({'x-token': GenericService.userData.token || ''})})
      .pipe(
        map((result: any) => result.fid),
        catchError(error => {
          this.handleError(error);
          return of('false');
        }));
  }

  readFrom(blob: Blob): Observable<string> {
    return Observable.create((observer: Subscriber<string>): void => {
      let reader = new FileReader();
      reader.onloadend = event => {
        let arrayBuffer: any = reader.result;
        let binary = String.fromCharCode.apply(null, Array.prototype.slice.apply(new Uint8Array(arrayBuffer)));
        observer.next(binary);
        observer.complete();
      };
      reader.readAsArrayBuffer(blob);
    });
  }

  async remove(media: Media): Promise<boolean> {
    try {
      await this.http
        .delete(`${environment.apiBase}/file/${media.uuid}`, this.headers)
        .toPromise();
      return true;
    }catch(error: any) {
      this.handleError(error);
      return false;
    }
  }
}