import { Component, ViewChild, OnInit, AfterViewInit, ViewEncapsulation } from "@angular/core";
import { MatPaginator, MatSort, MatSnackBar } from "@angular/material";
import { Router } from "@angular/router";
import { TranslateService } from "@ngx-translate/core";
import { DataSource } from "@angular/cdk/table";
import { ProjectListingModel } from "../models/projects/ProjectListingModel";
import { ProjectService } from "../services/project/project.service";
import { ProjectCriteriaComponent } from "../shared/components/criteria/projects/projects-criteria.component";
import { ProjectCriteria } from "../models/criteria/project/ProjectCriteria";
import { Observable } from "rxjs/Observable";
import { DataTableRequest } from "../models/data-table/DataTableRequest";
import { SnackBarNotificationComponent } from "../shared/components/notificaiton/snack-bar-notification.component";

@Component({
  selector: 'app-project-listing-component',
  templateUrl: 'project-listing.component.html',
  styleUrls: ['./project-listing.component.scss'],
  providers: [ProjectService],
  encapsulation: ViewEncapsulation.None
})
export class ProjectListingComponent implements OnInit {

  @ViewChild(MatPaginator) _paginator: MatPaginator;
  @ViewChild(MatSort) sort: MatSort;
  @ViewChild(ProjectCriteriaComponent) criteria: ProjectCriteriaComponent;

  dataSource: ProjectDataSource | null;
  displayedColumns: String[] = ['name', 'abbreviation', 'start', 'end'];

  constructor(
    private projectService: ProjectService,
    private router: Router,
    private languageService: TranslateService,
    public snackBar: MatSnackBar,
  ) {

  }

  ngOnInit() {
    this.criteria.setCriteria(this.getDefaultCriteria());
    this.refresh();
    this.criteria.setRefreshCallback(() => this.refresh());
  }

  refresh() {
    this.dataSource = new ProjectDataSource(this.projectService, this._paginator, this.sort, this.languageService, this.snackBar, this.criteria);
  }

  rowClick(rowId: String) {
    this.router.navigate(['/project/' + rowId]);
  }

  getDefaultCriteria(): ProjectCriteria {
    const defaultCriteria = new ProjectCriteria();
    return defaultCriteria;
  }
}

export class ProjectDataSource extends DataSource<ProjectListingModel> {

  totalCount = 0;
  isLoadingResults = false;

  constructor(
    private _service: ProjectService,
    private _paginator: MatPaginator,
    private _sort: MatSort,
    private _languageService: TranslateService,
    private _snackBar: MatSnackBar,
    private _criteria: ProjectCriteriaComponent
  ) {
    super();

    //this._paginator.page.subscribe((pageEvent: PageEvent) => {
    //    this.store.dispatch(new LoadPhotosRequestAction(pageEvent.pageIndex, pageEvent.pageSize))
    //})
  }

  connect(): Observable<ProjectListingModel[]> {
    const displayDataChanges = [
      this._paginator.page
      //this._sort.matSortChange
    ];

    // If the user changes the sort order, reset back to the first page.
    //this._sort.matSortChange.subscribe(() => {
    //    this._paginator.pageIndex = 0;
    //})

    return Observable.merge(...displayDataChanges)
      .startWith(null)
      .switchMap(() => {
        setTimeout(() => {
          this.isLoadingResults = true;
        });
        const startIndex = this._paginator.pageIndex * this._paginator.pageSize;
        const request = new DataTableRequest<ProjectCriteria>(startIndex, this._paginator.pageSize);
        request.criteria = this._criteria.criteria;
        return this._service.getPaged(request);
      })
      .catch((error: any) => {
        this._snackBar.openFromComponent(SnackBarNotificationComponent, {
          data: { message: 'GENERAL.SNACK-BAR.FORMS-BAD-REQUEST', language: this._languageService },
          duration: 3000,
          extraClasses: ['snackbar-warning']
        });
        this._criteria.onCallbackError(error.error);
        return Observable.of(null);
      })
      .map(result => {
        setTimeout(() => {
          this.isLoadingResults = false;
        });
        return result;
      })
      .map(result => {
        if (!result) { return []; }
        if (this._paginator.pageIndex === 0) { this.totalCount = result.totalCount; }
        return result.data;
      });
  }

  disconnect() {
    // No-op
  }
}