import type Accessor from "../core/Accessor.js";
import type { ScreenPoint } from "../core/types.js";

export interface MagnifierProperties extends Partial<Pick<Magnifier, "factor" | "maskEnabled" | "maskUrl" | "offset" | "overlayEnabled" | "overlayUrl" | "position" | "size" | "visible">> {}

/**
 * The Magnifier allows end users to show a portion of the view
 * as a magnified image. An instance of this class can be accessed through
 * either [MapView.magnifier](https://developers.arcgis.com/javascript/latest/references/core/views/MapView/#magnifier) or [SceneView.magnifier](https://developers.arcgis.com/javascript/latest/references/core/views/SceneView/#magnifier).
 *
 * ![magnifier-overlay](https://developers.arcgis.com/javascript/latest/assets/references/core/views/magnifier/magnifier-overlay.png)
 *
 * As you can see in the screenshot above, the Magnifier utilizes a default overlay image of a magnifier
 * glass. The overlay image is set using the [overlayUrl](https://developers.arcgis.com/javascript/latest/references/core/views/Magnifier/#overlayUrl) property. You can disable the overlay image by setting the [overlayEnabled](https://developers.arcgis.com/javascript/latest/references/core/views/Magnifier/#overlayEnabled) to `false`. The following
 * demonstrates using a Magnifier without an overlay image.
 *
 * ![magnifier-no-overlay](https://developers.arcgis.com/javascript/latest/assets/references/core/views/magnifier/magnifier-no-overlay.png)
 *
 * The Magnifier contains a default mask image, which is set using the [maskUrl](https://developers.arcgis.com/javascript/latest/references/core/views/Magnifier/#maskUrl), and determines the visible area of the magnified image. Be default, the magnified area
 * is in the shape of a circle. The following demonstrates an example of a mask image set in the shape of a square. Note that the `overlayEnabled` was set
 * to `false` in this example as well to hide the overlay image, and only display the magnified area.
 *
 * ![magnifier-maskUrl](https://developers.arcgis.com/javascript/latest/assets/references/core/views/magnifier/magnifier-maskUrl.png)
 *
 * @since 4.19
 * @see [MapView.magnifier](https://developers.arcgis.com/javascript/latest/references/core/views/MapView/#magnifier)
 * @see [SceneView.magnifier](https://developers.arcgis.com/javascript/latest/references/core/views/SceneView/#magnifier)
 * @example
 * view.when(() => {
 *   view.magnifier.visible = true;
 *
 *   const offset = view.magnifier.size / 2;
 *   view.magnifier.offset = { x: offset, y: offset };
 *
 *   //The magnifier will be displayed whenever the cursor hovers over the map.
 *   view.on("pointer-move", function (event) {
 *     view.magnifier.position = { x: event.x, y: event.y };
 *   });
 * });
 */
export default class Magnifier extends Accessor {
  constructor(properties?: MagnifierProperties);
  /**
   * Controls the amount of magnification to display. The larger the value, the more augmented the magnified image appears.
   *
   * @default 1.5
   */
  accessor factor: number;
  /**
   * Indicates whether the mask image is enabled.
   *
   * @default true
   */
  accessor maskEnabled: boolean;
  /**
   * The mask url points to an image that determines the visible area of the magnified image [(alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha).
   * A default built-in circle mask with a diameter equal to the size of the magnifier is used when the
   * maskUrl is null.
   */
  accessor maskUrl: string | null | undefined;
  /**
   * The offset of the magnifier in pixels. The offset allows to adjust where the magnifier is
   * drawn relative to its [position](https://developers.arcgis.com/javascript/latest/references/core/views/Magnifier/#position).
   *
   * @example
   * const offset = view.magnifier.size / 2;
   * view.magnifier.offset = { x: offset, y: offset };
   */
  accessor offset: ScreenPoint;
  /**
   * Indicates whether the overlay image is enabled.
   *
   * @default true
   */
  accessor overlayEnabled: boolean;
  /**
   * The overlay url points to an image that is displayed on top of the magnified image. Note
   * that the overlay image is not affected by the [maskUrl](https://developers.arcgis.com/javascript/latest/references/core/views/Magnifier/#maskUrl). A default
   * built-in image of a magnifier glass is used when the overlayUrl is null.
   */
  accessor overlayUrl: string | null | undefined;
  /** The position of the magnifier in pixels. The magnifier will not be displayed if the position is null. */
  accessor position: ScreenPoint | null | undefined;
  /**
   * The size of the magnifier in pixels.
   *
   * @default 120
   */
  accessor size: number;
  /**
   * Indicates whether the magnifier is visible.
   *
   * @default true
   */
  accessor visible: boolean;
}