import {ListWrapper, List} from 'angular2/src/facade/collection';
import {ResolvedBinding} from 'angular2/di';
import {isPresent, isBlank} from 'angular2/src/facade/lang';

import * as avmModule from './view_manager';
import * as viewModule from './view';

import {ElementRef} from './element_ref';
import {ViewRef, ProtoViewRef, internalView} from './view_ref';

export class ViewContainerRef {
  constructor(public viewManager: avmModule.AppViewManager, public element: ElementRef) {}

  private _getViews(): List<viewModule.AppView> {
    var vc = internalView(this.element.parentView).viewContainers[this.element.boundElementIndex];
    return isPresent(vc) ? vc.views : [];
  }

  clear(): void {
    for (var i = this.length - 1; i >= 0; i--) {
      this.remove(i);
    }
  }

  get(index: number): ViewRef { return this._getViews()[index].ref; }

  get length(): number { return this._getViews().length; }

  // TODO(rado): profile and decide whether bounds checks should be added
  // to the methods below.
  create(protoViewRef: ProtoViewRef = null, atIndex: number = -1, context: ElementRef = null,
         bindings: ResolvedBinding[] = null): ViewRef {
    if (atIndex == -1) atIndex = this.length;
    return this.viewManager.createViewInContainer(this.element, atIndex, protoViewRef, context,
                                                  bindings);
  }

  insert(viewRef: ViewRef, atIndex: number = -1): ViewRef {
    if (atIndex == -1) atIndex = this.length;
    return this.viewManager.attachViewInContainer(this.element, atIndex, viewRef);
  }

  indexOf(viewRef: ViewRef): number {
    return ListWrapper.indexOf(this._getViews(), internalView(viewRef));
  }

  remove(atIndex: number = -1): void {
    if (atIndex == -1) atIndex = this.length - 1;
    this.viewManager.destroyViewInContainer(this.element, atIndex);
    // view is intentionally not returned to the client.
  }

  /**
   * The method can be used together with insert to implement a view move, i.e.
   * moving the dom nodes while the directives in the view stay intact.
   */
  detach(atIndex: number = -1): ViewRef {
    if (atIndex == -1) atIndex = this.length - 1;
    return this.viewManager.detachViewInContainer(this.element, atIndex);
  }
}