/*
 * Copyright (C) 2018 StApps
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation, version 3.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program. If not, see <https://www.gnu.org/licenses/>.
 */
import {Component} from '@angular/core';
import {AlertController, LoadingController} from '@ionic/angular';
import {Client} from '@openstapps/api/lib/client';
import {SCThing} from '@openstapps/core';
import {Subject} from 'rxjs';
import {debounceTime, distinctUntilChanged} from 'rxjs/operators';
import {StAppsWebHttpClient} from '../stapps-web-http-client.provider';

@Component({
  selector: 'stapps-data-list',
  templateUrl: 'data-list.html',
})
export class DataListComponent {
  selectedItem: any;
  items: SCThing[] = [];

  client: Client;

  size: number = 30;
  from: number = 0;

  query: string;
  queryChanged: Subject<string> = new Subject<string>();

  loading: HTMLIonLoadingElement;

  constructor(private loadingController: LoadingController,
    private alertController: AlertController,
    swHttpClient: StAppsWebHttpClient) {
    this.client = new Client(swHttpClient, 'https://stappsbe01.innocampus.tu-berlin.de', '1.0.6');

    this.queryChanged
      .pipe(
        debounceTime(1000),
        distinctUntilChanged())
      .subscribe((model) => {
        this.from = 0;
        this.query = model;
        this.items = [];
        this.fetchItems();
      });

    this.fetchItems();
  }

  search(query: string) {
    this.queryChanged.next(query);
  }

  async loadMore(event: any): Promise<any> {
    this.from += this.size;
    await this.fetchItems();
    event.target.complete();
    return;
  }

  private async fetchItems(): Promise<any> {
    if (this.from === 0) {
      this.loading = await this.loadingController.create();
      await this.loading.present();
    }

    return this.client.search({
      from: this.from,
      query: this.query,
      size: this.size
    } as any).then((result) => {
      result.data.forEach((item) => {
        this.items.push(item);
      });

      if (this.from === 0) {
        this.loading.dismiss();
      }
    }, async (err) => {
      const alert: HTMLIonAlertElement = await this.alertController.create({
        buttons: ['Dismiss'],
        header: 'Error',
        subHeader: err.message,
      });

      await alert.present();

      await this.loading.dismiss();
    });
  }
}