source: node_modules/recharts/es6/state/selectors/combiners/combineTooltipPayloadConfigurations.js

export var combineTooltipPayloadConfigurations = (tooltipState, tooltipEventType, trigger, defaultIndex) => {
  // if tooltip reacts to axis interaction, then we display all items at the same time.
  if (tooltipEventType === 'axis') {
    return tooltipState.tooltipItemPayloads;
  }
  /*
   * By now we already know that tooltipEventType is 'item', so we can only search in itemInteractions.
   * item means that only the hovered or clicked item will be present in the tooltip.
   */
  if (tooltipState.tooltipItemPayloads.length === 0) {
    // No point filtering if the payload is empty
    return [];
  }
  var filterByGraphicalItemId;
  if (trigger === 'hover') {
    filterByGraphicalItemId = tooltipState.itemInteraction.hover.graphicalItemId;
  } else {
    filterByGraphicalItemId = tooltipState.itemInteraction.click.graphicalItemId;
  }
  if (filterByGraphicalItemId == null && defaultIndex != null) {
    /*
     * So when we use `defaultIndex` - we don't have a dataKey to filter by because user did not hover over anything yet.
     * In that case let's display the first item in the tooltip; after all, this is `item` interaction case,
     * so we should display only one item at a time instead of all.
     */
    var firstItemPayload = tooltipState.tooltipItemPayloads[0];
    if (firstItemPayload != null) {
      return [firstItemPayload];
    }
    return [];
  }
  return tooltipState.tooltipItemPayloads.filter(tpc => {
    var _tpc$settings;
    return ((_tpc$settings = tpc.settings) === null || _tpc$settings === void 0 ? void 0 : _tpc$settings.graphicalItemId) === filterByGraphicalItemId;
  });
};