import { Component } from '@angular/core';
import 'chance';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css'],
})
export class AppComponent {
  /** Store the current loading state */
  isLoading: boolean = false;

  /** Store the list of employees */
  employees: ReadonlyArray<Employee> = [];

  /** Store the current page */
  private _page: number = 0;

  constructor() {
    // load the first page
    this.load();
  }

  load(page: number = 0): void {
    // update the loading state
    this.isLoading = true;

    // create some new employees
    const employees: Employee[] = [];

    for (let idx = 1; idx <= 5000; idx++) {
      employees.push({
        id: idx + 5000 * page,
        name: chance.name(),
        email: chance.email(),
        department: chance.pickone([
          'Finance',
          'Operations',
          'Investor Relations',
          'Technical',
          'Auditing',
          'Labs',
        ]),
      });
    }

    // add delay to simulate server loading
    setTimeout(() => {
      this.employees = [...this.employees, ...employees];
      this.isLoading = false;
    }, 1000);
  }

  loadNextPage(): void {
    this.load(++this._page);
  }
}

export interface Employee {
  id: number;
  name: string;
  email: string;
  department: string;
}