ant-design/components/_util/hooks/useZIndex.ts

import React from 'react';

import useToken from '../../theme/useToken';
import { devUseWarning } from '../warning';
import zIndexContext from '../zindexContext';

export type ZIndexContainer =
  | 'Modal'
  | 'Drawer'
  | 'Popover'
  | 'Popconfirm'
  | 'Tooltip'
  | 'Tour'
  | 'FloatButton';

export type ZIndexConsumer = 'SelectLike' | 'Dropdown' | 'DatePicker' | 'Menu' | 'ImagePreview';

// Z-Index control range
// Container: 1000 + offset 100 (max base + 10 * offset = 2000)
// Popover: offset 50
// Notification: Container Max zIndex + componentOffset

const CONTAINER_OFFSET = 100;
const CONTAINER_OFFSET_MAX_COUNT = 10;

export const CONTAINER_MAX_OFFSET = CONTAINER_OFFSET * CONTAINER_OFFSET_MAX_COUNT;

/**
 * Static function will default be the `CONTAINER_MAX_OFFSET`.
 * But it still may have children component like Select, Dropdown.
 * So the warning zIndex should exceed the `CONTAINER_MAX_OFFSET`.
 */
const CONTAINER_MAX_OFFSET_WITH_CHILDREN = CONTAINER_MAX_OFFSET + CONTAINER_OFFSET;

export const containerBaseZIndexOffset: Record<ZIndexContainer, number> = {
  Modal: CONTAINER_OFFSET,
  Drawer: CONTAINER_OFFSET,
  Popover: CONTAINER_OFFSET,
  Popconfirm: CONTAINER_OFFSET,
  Tooltip: CONTAINER_OFFSET,
  Tour: CONTAINER_OFFSET,
  FloatButton: CONTAINER_OFFSET,
};

export const consumerBaseZIndexOffset: Record<ZIndexConsumer, number> = {
  SelectLike: 50,
  Dropdown: 50,
  DatePicker: 50,
  Menu: 50,
  ImagePreview: 1,
};

function isContainerType(type: ZIndexContainer | ZIndexConsumer): type is ZIndexContainer {
  return type in containerBaseZIndexOffset;
}

type ReturnResult = [zIndex: number | undefined, contextZIndex: number];

export const useZIndex = (
  componentType: ZIndexContainer | ZIndexConsumer,
  customZIndex?: number,
): ReturnResult => {
  const [, token] = useToken();
  const parentZIndex = React.useContext(zIndexContext);
  const isContainer = isContainerType(componentType);

  let result: ReturnResult;

  if (customZIndex !== undefined) {
    result = [customZIndex, customZIndex];
  } else {
    let zIndex = parentZIndex ?? 0;

    if (isContainer) {
      zIndex +=
        // Use preset token zIndex by default but not stack when has parent container
        (parentZIndex ? 0 : token.zIndexPopupBase) +
        // Container offset
        containerBaseZIndexOffset[componentType];
    } else {
      zIndex += consumerBaseZIndexOffset[componentType];
    }
    result = [parentZIndex === undefined ? customZIndex : zIndex, zIndex];
  }

  if (process.env.NODE_ENV !== 'production') {
    const warning = devUseWarning(componentType);

    const maxZIndex = token.zIndexPopupBase + CONTAINER_MAX_OFFSET_WITH_CHILDREN;
    const currentZIndex = result[0] || 0;

    warning(
      customZIndex !== undefined || currentZIndex <= maxZIndex,
      'usage',
      '`zIndex` is over design token `zIndexPopupBase` too much. It may cause unexpected override.',
    );
  }

  return result;
};