import { Injectable } from '@angular/core';
import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import { Observable, of, Subject } from 'rxjs';
import { catchError } from 'rxjs/operators';
import { MeTubeSocket } from './metube-socket';

export interface Status {
  status: string;
  msg?: string;
}

export interface Download {
  id: string;
  title: string;
  url: string;
  quality: string;
  format: string;
  folder: string;
  custom_name_prefix: string;
  playlist_strict_mode: boolean;
  playlist_item_limit: number;
  status: string;
  msg: string;
  percent: number;
  speed: number;
  eta: number;
  filename: string;
  checked?: boolean;
  deleting?: boolean;
}

@Injectable({
  providedIn: 'root'
})
export class DownloadsService {
  loading = true;
  queue = new Map<string, Download>();
  done = new Map<string, Download>();
  queueChanged = new Subject();
  doneChanged = new Subject();
  customDirsChanged = new Subject();
  ytdlOptionsChanged = new Subject();
  configurationChanged = new Subject();
  updated = new Subject();

  configuration = {};
  customDirs = {};

  constructor(private http: HttpClient, private socket: MeTubeSocket) {
    socket.fromEvent('all').subscribe((strdata: string) => {
      this.loading = false;
      let data: [[[string, Download]], [[string, Download]]] = JSON.parse(strdata);
      this.queue.clear();
      data[0].forEach(entry => this.queue.set(...entry));
      this.done.clear();
      data[1].forEach(entry => this.done.set(...entry));
      this.queueChanged.next(null);
      this.doneChanged.next(null);
    });
    socket.fromEvent('added').subscribe((strdata: string) => {
      let data: Download = JSON.parse(strdata);
      this.queue.set(data.url, data);
      this.queueChanged.next(null);
    });
    socket.fromEvent('updated').subscribe((strdata: string) => {
      let data: Download = JSON.parse(strdata);
      let dl: Download = this.queue.get(data.url);
      data.checked = dl.checked;
      data.deleting = dl.deleting;
      this.queue.set(data.url, data);
      this.updated.next(null);
    });
    socket.fromEvent('completed').subscribe((strdata: string) => {
      let data: Download = JSON.parse(strdata);
      this.queue.delete(data.url);
      this.done.set(data.url, data);
      this.queueChanged.next(null);
      this.doneChanged.next(null);
    });
    socket.fromEvent('canceled').subscribe((strdata: string) => {
      let data: string = JSON.parse(strdata);
      this.queue.delete(data);
      this.queueChanged.next(null);
    });
    socket.fromEvent('cleared').subscribe((strdata: string) => {
      let data: string = JSON.parse(strdata);
      this.done.delete(data);
      this.doneChanged.next(null);
    });
    socket.fromEvent('configuration').subscribe((strdata: string) => {
      let data = JSON.parse(strdata);
      console.debug("got configuration:", data);
      this.configuration = data;
      this.configurationChanged.next(data);
    });
    socket.fromEvent('custom_dirs').subscribe((strdata: string) => {
      let data = JSON.parse(strdata);
      console.debug("got custom_dirs:", data);
      this.customDirs = data;
      this.customDirsChanged.next(data);
    });
    socket.fromEvent('ytdl_options_changed').subscribe((strdata: string) => {
      let data = JSON.parse(strdata);
      this.ytdlOptionsChanged.next(data);
    });
  }

  handleHTTPError(error: HttpErrorResponse) {
    var msg = error.error instanceof ErrorEvent ? error.error.message : error.error;
    return of({status: 'error', msg: msg})
  }

  public add(url: string, quality: string, format: string, folder: string, customNamePrefix: string, playlistStrictMode: boolean, playlistItemLimit: number, autoStart: boolean) {
    return this.http.post<Status>('add', {url: url, quality: quality, format: format, folder: folder, custom_name_prefix: customNamePrefix, playlist_strict_mode: playlistStrictMode, playlist_item_limit: playlistItemLimit, auto_start: autoStart}).pipe(
      catchError(this.handleHTTPError)
    );
  }

  public startById(ids: string[]) {
    return this.http.post('start', {ids: ids});
  }

  public delById(where: string, ids: string[]) {
    ids.forEach(id => this[where].get(id).deleting = true);
    return this.http.post('delete', {where: where, ids: ids});
  }

  public startByFilter(where: string, filter: (dl: Download) => boolean) {
    let ids: string[] = [];
    this[where].forEach((dl: Download) => { if (filter(dl)) ids.push(dl.url) });
    return this.startById(ids);
  }

  public delByFilter(where: string, filter: (dl: Download) => boolean) {
    let ids: string[] = [];
    this[where].forEach((dl: Download) => { if (filter(dl)) ids.push(dl.url) });
    return this.delById(where, ids);
  }
  public addDownloadByUrl(url: string): Promise<any> {
    const defaultQuality = 'best';
    const defaultFormat = 'mp4';
    const defaultFolder = ''; 
    const defaultCustomNamePrefix = '';
    const defaultPlaylistStrictMode = false;
    const defaultPlaylistItemLimit = 0;
    const defaultAutoStart = true;
    
    return new Promise((resolve, reject) => {
      this.add(url, defaultQuality, defaultFormat, defaultFolder, defaultCustomNamePrefix, defaultPlaylistStrictMode, defaultPlaylistItemLimit, defaultAutoStart)
        .subscribe(
          response => resolve(response),
          error => reject(error)
        );
    });
  }
  public exportQueueUrls(): string[] {
    return Array.from(this.queue.values()).map(download => download.url);
  }
  
  
}