item-selection/es/immutable.js

Manage item multi-selections.

function range(start, end) {
  if (start > end) {
    var _ref = [end, start];
    start = _ref[0];
    end = _ref[1];
  }

  var list = [];

  for (var i = start; i <= end; i++) {
    list.push(i);
  }

  return list;
}

var includes = function includes(arr, item) {
  return arr.indexOf(item) !== -1;
};

var cmp = function cmp(a, b) {
  if (a > b) return 1;
  if (a < b) return -1;
  return 0;
};

var ItemSelection =
/*#__PURE__*/
function () {
  function ItemSelection(items, selection, lastIndex) {
    if (selection === void 0) {
      selection = [];
    }

    if (lastIndex === void 0) {
      lastIndex = null;
    }

    if (!Array.isArray(items)) {
      throw new TypeError('Expected an array');
    }

    this.items = items;
    this.selection = selection;
    this.lastIndex = lastIndex;
  }

  var _proto = ItemSelection.prototype;

  _proto.getIndices = function getIndices() {
    return this.selection.slice().sort(cmp);
  };

  _proto.get = function get() {
    var _this = this;

    return this.getIndices().map(function (index) {
      return _this.items[index];
    });
  };

  _proto.set = function set(selection, lastIndex) {
    return new ItemSelection(this.items, selection, lastIndex);
  };

  _proto.isSelectedIndex = function isSelectedIndex(index) {
    return includes(this.selection, index);
  };

  _proto.isSelected = function isSelected(item) {
    return includes(this.get(), item);
  };

  _proto.clear = function clear() {
    return this.set([], null);
  };

  _proto.add = function add(index) {
    return this.set([].concat(this.selection, [index]), this.lastIndex);
  };

  _proto.remove = function remove(index) {
    return this.set(this.selection.filter(function (idx) {
      return idx !== index;
    }), null);
  };

  _proto.select = function select(index) {
    return this.set([index], index);
  };

  _proto.deselect = function deselect(index) {
    return this.remove(index);
  };

  _proto.selectRange = function selectRange(index, end) {
    if (end === void 0) {
      end = null;
    }

    if (end !== null) {
      return this.set(range(index, end), null);
    }

    if (typeof this.lastIndex !== 'number') {
      return this.select(index);
    }

    return this.set(range(this.lastIndex, index), this.lastIndex);
  };

  _proto.selectToggle = function selectToggle(index) {
    if (this.isSelectedIndex(index)) {
      return this.remove(index);
    }

    return this.set([].concat(this.selection, [index]), index);
  };

  _proto.selectAll = function selectAll() {
    return this.set(this.items.map(function (item, index) {
      return index;
    }), null);
  };

  return ItemSelection;
}();

export default function itemSelection(items, selection, lastIndex) {
  return new ItemSelection(items, selection, lastIndex);
}
export { ItemSelection };