@enact/ui/internal/selection/selection.js

A collection of simplified unstyled cross-platform UI components for Enact

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.select = exports.isSelected = void 0;
var _curry = _interopRequireDefault(require("ramda/src/curry"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { "default": e }; }
/**
 * Determines if `item` is selected
 *
 * @param	{*}			item		Usually a number but could be anything within the `selected` list
 * @param	{*|Array}	selected	One or many selected items
 *
 * @returns	{Boolean}				`true` if item is equal to or contained in `selected`
 * @private
 */
var isSelected = exports.isSelected = (0, _curry["default"])(function (item, selected) {
  return item === selected || Array.isArray(selected) && selected.indexOf(item) >= 0;
});

/**
 * Selects or deselects an `item` based on the `mode` and returns a copy of `selected` with the new
 * selected state.
 *
 * `single` - Toggles the selection state of `item`. Always returns either `item` or null.
 * `radio` - Always selects `item`
 * `multiple` - Toggles the selection state `item` like `single` but doesn't replace other selected
 * items.
 *
 * @param	{String}	mode		Selection mode (`single`, `radio`, or `multiple`)
 * @param	{*}			item		The selected item
 * @param	{*|Array}	selected	The current selection
 *
 * @returns {*|Array}				The updated selection
 * @private
 */
var select = exports.select = (0, _curry["default"])(function (mode, item, selected) {
  if (mode === 'radio') {
    // When selection is disabled, when selecting only 1, or when selecting the
    // first of multiple, we can forward the source event as is.
    return item;
  } else if (mode === 'single') {
    // When selecting 0 or 1, we have to unselect it if selected
    return isSelected(item, selected) ? null : item;
  } else if (selected == null) {
    // When selection 0 or n but no prior selection, wrap item in an array
    return [item];
  } else {
    // Otherwise we're selecting multiple so we have to either deselect it if
    // already selected or select it if not.
    var updated = Array.isArray(selected) ? selected.slice() : [selected];
    var index = updated.indexOf(item);
    if (index >= 0) {
      if (updated.length === 1) {
        // item should be deselected and is the only item in the array so return null
        updated = null;
      } else {
        // otherwise there are multiple selected so remove item
        updated.splice(index, 1);
      }
    } else {
      // insert and sort
      updated.push(item);
      updated = updated.sort(function (a, b) {
        return a - b;
      });
    }
    return updated;
  }
});