import {View, ElementRef} from 'angular2/angular2';

import {Ion} from '../ion';
import {IonicConfig} from '../../config/config';
import {IonicComponent} from '../../config/annotations';


/**
 * ion-scroll is a non-flexboxed scroll area that can
 * scroll horizontally or vertically.
 */
@IonicComponent({
  selector: 'ion-scroll',
  properties: [
    'scrollX', 'scrollY'
  ],
  host: {
    '[class.scroll-x]': 'scrollX',
    '[class.scroll-y]': 'scrollY'
  }
})
@View({
  template: '<scroll-content><ng-content></ng-content></scroll-content>'
})
export class Scroll extends Ion {
  constructor(elementRef: ElementRef, ionicConfig: IonicConfig) {
    super(elementRef, ionicConfig);

    setTimeout(() => {
      this.scrollElement = this.getNativeElement().children[0];
    });
  }

  addScrollEventListener(handler) {
    if(!this.scrollElement) { return; }

    this.scrollElement.addEventListener('scroll', handler);

    return () => {
      this.scrollElement.removeEventListener('scroll', handler);
    }
  }
}