import { Injectable } from '@angular/core';

import { App } from '../app/app';
import { Config } from '../../config/config';
import { Popover } from './popover';
import { PopoverOptions } from './popover-options';
import { DeepLinker } from '../../navigation/deep-linker';

/**
 * @name PopoverController
 * @description
 * A Popover is a dialog that appears on top of the current page.
 * It can be used for anything, but generally it is used for overflow
 * actions that don't fit in the navigation bar.
 *
 * ### Creating
 * A popover can be created by calling the `create` method. The view
 * to display in the popover should be passed as the first argument.
 * Any data to pass to the popover view can optionally be passed in
 * the second argument. Options for the popover can optionally be
 * passed in the third argument. See the [create](#create) method
 * below for all available options.
 *
 * ### Presenting
 * To present a popover, call the `present` method on a PopoverController instance.
 * In order to position the popover relative to the element clicked, a click event
 * needs to be passed into the options of the the `present method. If the event
 * is not passed, the popover will be positioned in the center of the current
 * view. See the [usage](#usage) section for an example of passing this event.
 *
 * ### Dismissing
 * To dismiss the popover after creation, call the `dismiss()` method on the
 * `Popover` instance. The popover can also be dismissed from within the popover's
 * view by calling the `dismiss()` method on the [ViewController](../../navigation/ViewController).
 * The `dismiss()` call accepts an optional parameter that will be passed to the callback described
 * as follows. The `onDidDismiss(<func>)` function can be called to set up a callback action that will
 * be performed after the popover is dismissed, receiving the parameter passed to `dismiss()`.
 * The popover will dismiss when the backdrop is clicked by implicitly performing `dismiss(null)`,
 * but this can be disabled by setting `enableBackdropDismiss` to `false` in the popover options.
 *
 * > Note that after the component is dismissed, it will not be usable anymore and
 * another one must be created. This can be avoided by wrapping the creation and
 * presentation of the component in a reusable function as shown in the [usage](#usage)
 * section below.
 *
 * @usage
 *
 * To open a popover on the click of a button, pass `$event` to the method
 * which creates and presents the popover:
 *
 * ```html
 * <button ion-button icon-only (click)="presentPopover($event)">
 *   <ion-icon name="more"></ion-icon>
 * </button>
 * ```
 *
 * ```ts
 * import { PopoverController } from 'ionic-angular';
 *
 * @Component({})
 * class MyPage {
 *   constructor(public popoverCtrl: PopoverController) {}
 *
 *   presentPopover(myEvent) {
 *     let popover = this.popoverCtrl.create(PopoverPage);
 *     popover.present({
 *       ev: myEvent
 *     });
 *   }
 * }
 * ```
 *
 * The `PopoverPage` will display inside of the popover, and
 * can be anything. Below is an example of a page with items
 * that close the popover on click.
 *
 * ```ts
 * @Component({
 *   template: `
 *     <ion-list>
 *       <ion-list-header>Ionic</ion-list-header>
 *       <button ion-item (click)="close()">Learn Ionic</button>
 *       <button ion-item (click)="close()">Documentation</button>
 *       <button ion-item (click)="close()">Showcase</button>
 *       <button ion-item (click)="close()">GitHub Repo</button>
 *     </ion-list>
 *   `
 * })
 * class PopoverPage {
 *   constructor(public viewCtrl: ViewController) {}
 *
 *   close() {
 *     this.viewCtrl.dismiss();
 *   }
 * }
 * ```
 * @advanced
 * Popover Options
 *
 * | Option                | Type       | Description                                                                                                      |
 * |-----------------------|------------|------------------------------------------------------------------------------------------------------------------|
 * | cssClass              |`string`    | Additional classes for custom styles, separated by spaces.                                                       |
 * | showBackdrop          |`boolean`   | Whether to show the backdrop. Default true.                                                                      |
 * | enableBackdropDismiss |`boolean`   | Whether the popover should be dismissed by tapping the backdrop. Default true.                                   |
 *
 *
 *
 * @demo /docs/demos/src/popover/
 */
@Injectable()
export class PopoverController {

  constructor(private _app: App, public config: Config, private _deepLinker: DeepLinker) { }

  /**
   * Present a popover. See below for options
   * @param {object} component The Popover
   * @param {object} data Any data to pass to the Popover view
   * @param {PopoverOptions} opts Popover options
   */
  create(component: any, data = {}, opts: PopoverOptions = {}): Popover {
    return new Popover(this._app, component, data, opts, this.config, this._deepLinker);
  }

}
