@prefect9/ui/components/DragDropFilesObserver.js

UI React components

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
require("core-js/modules/es.array.includes.js");
require("core-js/modules/es.string.includes.js");
require("core-js/modules/web.dom-collections.iterator.js");
var _isType = require("@prefect9/is-type");
function DragDropFilesObserver() {
  if (!this) throw new Error('Make DragDropFilesObserver as new object');
  if (this.constructor !== DragDropFilesObserver) throw new Error('Invalid DragDropFilesObserver this variable');
  const result = this;
  let destructed = false;
  const dragHandlers = [];
  let dragged = false;
  let nowDragged = false;
  const setDrag = newDrag => {
    nowDragged = newDrag;
    if (dragged === nowDragged) return;
    dragged = nowDragged;
    if (dragHandlers.length) for (let dragHandler of dragHandlers) dragHandler(nowDragged);
  };
  const dragStartHandler = e => {
    e.preventDefault();
    if (destructed) return;
    const types = e.dataTransfer.types;
    if (!types.includes('Files')) return;
    setDrag(true);
  };
  window.addEventListener('dragenter', dragStartHandler);
  window.addEventListener('dragover', dragStartHandler);
  const dragEndHandler = e => {
    e.preventDefault();
    if (destructed) return;
    const seed = "".concat(Math.random());
    nowDragged = seed;
    setTimeout(() => {
      if (destructed) return;
      if (nowDragged !== seed) return;
      setDrag(false);
    }, 100);
  };
  window.addEventListener('dragleave', dragEndHandler);
  result.onDrag = handler => {
    if (destructed) throw new Error('Observer already destructed');
    if (!(0, _isType.isFunc)(handler)) throw new Error('Handler must be function');
    handler(dragged);
    dragHandlers.push(handler);
  };
  const dropHandlers = [];
  const dropHandler = e => {
    e.preventDefault();
    if (destructed) return;
    setDrag(false);
    const files = e.dataTransfer.files;
    if (!files.length) return;
    if (dropHandlers.length) for (let dropHandler of dropHandlers) dropHandler(files);
  };
  window.addEventListener('drop', dropHandler);
  result.onDrop = handler => {
    if (destructed) throw new Error('Observer already destructed');
    if (!(0, _isType.isFunc)(handler)) throw new Error('Handler must be function');
    dropHandlers.push(handler);
  };
  result.destruct = () => {
    window.removeEventListener('dragenter', dragStartHandler);
    window.removeEventListener('dragover', dragStartHandler);
    window.removeEventListener('dragleave', dragEndHandler);
    window.removeEventListener('drop', dropHandler);
    setDrag(false);
    destructed = true;
  };
}
var _default = exports.default = DragDropFilesObserver;