mastodon/app/javascript/mastodon/features/ui/components/tabs_bar.js

import React from 'react';
import PropTypes from 'prop-types';
import { NavLink, withRouter } from 'react-router-dom';
import { FormattedMessage, injectIntl } from 'react-intl';
import { debounce } from 'lodash';
import { isUserTouching } from '../../../is_mobile';
import Icon from 'mastodon/components/icon';
import NotificationsCounterIcon from './notifications_counter_icon';

export const links = [
  <NavLink
    className='tabs-bar__link'
    to='/timelines/home'
    data-preview-title-id='column.home'
    data-preview-icon='home'
  ><Icon
      id='home'
      fixedWidth
  /><FormattedMessage
      id='tabs_bar.home'
      defaultMessage='Home'
    /></NavLink >,
  <NavLink
    className='tabs-bar__link'
    to='/notifications'
    data-preview-title-id='column.notifications'
    data-preview-icon='bell'
  ><NotificationsCounterIcon /><FormattedMessage
      id='tabs_bar.notifications'
      defaultMessage='Notifications'
  /></NavLink >,
  <NavLink
    className='tabs-bar__link'
    to='/timelines/public/local'
    data-preview-title-id='column.community'
    data-preview-icon='users'
  ><Icon
      id='users'
      fixedWidth
  /><FormattedMessage
      id='tabs_bar.local_timeline'
      defaultMessage='Local'
    /></NavLink >,
  <NavLink
    className='tabs-bar__link'
    exact
    to='/timelines/public'
    data-preview-title-id='column.public'
    data-preview-icon='globe'
  ><Icon
      id='globe'
      fixedWidth
  /><FormattedMessage
      id='tabs_bar.federated_timeline'
      defaultMessage='Federated'
    /></NavLink >,
  <NavLink
    className='tabs-bar__link optional'
    to='/search'
    data-preview-title-id='tabs_bar.search'
    data-preview-icon='bell'
  ><Icon
      id='search'
      fixedWidth
  /><FormattedMessage
      id='tabs_bar.search'
      defaultMessage='Search'
    /></NavLink >,
  <NavLink
    className='tabs-bar__link'
    style={{ flexGrow: '0', flexBasis: '30px' }}
    to='/getting-started'
    data-preview-title-id='getting_started.heading'
    data-preview-icon='bars'
  ><Icon
      id='bars'
      fixedWidth
  /></NavLink >,
];

export function getIndex(path) {
  return links.findIndex(link => link.props.to === path);
}

export function getLink(index) {
  return links[index].props.to;
}

export default @injectIntl
@withRouter
class TabsBar extends React.PureComponent {

  static propTypes = {
    intl   : PropTypes.object.isRequired,
    history: PropTypes.object.isRequired,
  };

  setRef = ref => {
    this.node = ref;
  };

  handleClick = (e) => {
    // Only apply optimization for touch devices, which we assume are slower
    // We thus avoid the 250ms delay for non-touch devices and the lag for touch devices
    if (isUserTouching()) {
      e.preventDefault();
      e.persist();

      requestAnimationFrame(() => {
        const tabs = Array(...this.node.querySelectorAll('.tabs-bar__link'));
        const currentTab = tabs.find(tab => tab.classList.contains('active'));
        const nextTab = tabs.find(tab => tab.contains(e.target));
        const { props: { to } } = links[Array(...this.node.childNodes).indexOf(nextTab)];

        if (currentTab !== nextTab) {
          if (currentTab) {
            currentTab.classList.remove('active');
          }

          const listener = debounce(() => {
            nextTab.removeEventListener('transitionend', listener);
            this.props.history.push(to);
          }, 50);

          nextTab.addEventListener('transitionend', listener);
          nextTab.classList.add('active');
        }
      });
    }

  };

  render() {
    const { intl: { formatMessage } } = this.props;

    return (
      <div className='tabs-bar__wrapper'>

        <nav
          className='tabs-bar'
          ref={this.setRef}
        >
          {links.map(link => React.cloneElement(link, {
            key         : link.props.to,
            onClick     : this.handleClick,
            'aria-label': formatMessage({ id: link.props['data-preview-title-id'] }),
          }))}
        </nav >

        <div id='tabs-bar__portal' />

      </div >
    );
  }

}