/**
 * A helper that fires canvas localized drag events and realizes
 * the general "drag-and-drop" look and feel.
 *
 * Calling {@link Dragging#activate} activates dragging on a canvas.
 *
 * It provides the following:
 *
 *   * emits life cycle events, namespaced with a prefix assigned
 *     during dragging activation
 *   * sets and restores the cursor
 *   * sets and restores the selection if elements still exist
 *   * ensures there can be only one drag operation active at a time
 *
 * Dragging may be canceled manually by calling {@link Dragging#cancel}
 * or by pressing ESC.
 *
 *
 * ## Life-cycle events
 *
 * Dragging can be in three different states, off, initialized
 * and active.
 *
 * (1) off: no dragging operation is in progress
 * (2) initialized: a new drag operation got initialized but not yet
 *                  started (i.e. because of no initial move)
 * (3) started: dragging is in progress
 *
 * Eventually dragging will be off again after a drag operation has
 * been ended or canceled via user click or ESC key press.
 *
 * To indicate transitions between these states dragging emits generic
 * life-cycle events with the `drag.` prefix _and_ events namespaced
 * to a prefix choosen by a user during drag initialization.
 *
 * The following events are emitted (appropriately prefixed) via
 * the {@link EventBus}.
 *
 * * `init`
 * * `start`
 * * `move`
 * * `end`
 * * `ended` (dragging already in off state)
 * * `cancel` (only if previously started)
 * * `canceled` (dragging already in off state, only if previously started)
 * * `cleanup`
 *
 *
 * @example
 *
 * ```javascript
 * function MyDragComponent(eventBus, dragging) {
 *
 *   eventBus.on('mydrag.start', function(event) {
 *     console.log('yes, we start dragging');
 *   });
 *
 *   eventBus.on('mydrag.move', function(event) {
 *     console.log('canvas local coordinates', event.x, event.y, event.dx, event.dy);
 *
 *     // local drag data is passed with the event
 *     event.context.foo; // "BAR"
 *
 *     // the original mouse event, too
 *     event.originalEvent; // MouseEvent(...)
 *   });
 *
 *   eventBus.on('element.click', function(event) {
 *     dragging.init(event, 'mydrag', {
 *       cursor: 'grabbing',
 *       data: {
 *         context: {
 *           foo: "BAR"
 *         }
 *       }
 *     });
 *   });
 * }
 * ```
 *
 */
export default class Dragging {
  static $inject: string[];

  /**
   * @param eventBus
   * @param canvas
   * @param selection
   * @param elementRegistry
   */
  constructor(eventBus: EventBus, canvas: Canvas, selection: Selection, elementRegistry: ElementRegistry);

  init(prefix: string, options?: any): void;
  init(relativeTo: Point, prefix: string, options?: any): void;
  init(event: MouseEvent | TouchEvent, prefix: string, options?: any): void;

  init(
    event: MouseEvent | TouchEvent,
    relativeTo: Point,
    prefix: string,
    options?: any
  ): void;

  move: (event: any, activate: any) => void;
  hover: (event: any) => void;
  out: (event: any) => void;
  end: (event: any) => void;
  cancel: (restore: any) => void;
  context: () => any;
  setOptions: (options: any) => void;
}

type Point = import("../../util/Types").Point;
type Canvas = import("../../core/Canvas").default;
type ElementRegistry = import("../../core/ElementRegistry").default;
type EventBus = import("../../core/EventBus").default;
type Selection = import("../selection/Selection").default;