Search.js

import cx from 'clsx'
import keyboardKey from 'keyboard-key'
import _ from 'lodash'
import PropTypes from 'prop-types'
import React from 'react'
import shallowEqual from 'shallowequal'

import {
  ModernAutoControlledComponent as Component,
  customPropTypes,
  eventStack,
  getElementType,
  getUnhandledProps,
  htmlInputAttrs,
  isBrowser,
  makeDebugger,
  objectDiff,
  partitionHTMLProps,
  SUI,
  useKeyOnly,
  useValueAndKey,
} from '../../lib'
import Input from '../../elements/Input'
import SearchCategory from './SearchCategory'
import SearchResult from './SearchResult'
import SearchResults from './SearchResults'

const debug = makeDebugger('search')

const overrideSearchInputProps = (predefinedProps) => {
  const { input } = predefinedProps

  if (_.isUndefined(input)) {
    return { ...predefinedProps, input: { className: 'prompt' } }
  }
  if (_.isPlainObject(input)) {
    return { ...predefinedProps, input: { ...input, className: cx(input.className, 'prompt') } }
  }

  return predefinedProps
}

/**
 * A search module allows a user to query for results from a selection of data
 */
export default class Search extends Component {
  static getAutoControlledStateFromProps(props, state) {
    debug('getAutoControlledStateFromProps()')

    // We need to store a `prevValue` to compare as in `getDerivedStateFromProps` we don't have
    // prevState
    if (typeof state.prevValue !== 'undefined' && shallowEqual(state.prevValue, state.value)) {
      return { prevValue: state.value }
    }

    const selectedIndex = props.selectFirstResult ? 0 : -1
    debug('value changed, setting selectedIndex', selectedIndex)

    return { prevValue: state.value, selectedIndex }
  }

  shouldComponentUpdate(nextProps, nextState) {
    return !shallowEqual(nextProps, this.props) || !shallowEqual(nextState, this.state)
  }

  componentDidUpdate(prevProps, prevState) {
    // eslint-disable-line complexity
    debug('componentDidUpdate()')
    debug('to state:', objectDiff(prevState, this.state))

    // focused / blurred
    if (!prevState.focus && this.state.focus) {
      debug('search focused')
      if (!this.isMouseDown) {
        debug('mouse is not down, opening')
        this.tryOpen()
      }
      if (this.state.open) {
        eventStack.sub('keydown', [this.moveSelectionOnKeyDown, this.selectItemOnEnter])
      }
    } else if (prevState.focus && !this.state.focus) {
      debug('search blurred')
      if (!this.isMouseDown) {
        debug('mouse is not down, closing')
        this.close()
      }
      eventStack.unsub('keydown', [this.moveSelectionOnKeyDown, this.selectItemOnEnter])
    }

    // opened / closed
    if (!prevState.open && this.state.open) {
      debug('search opened')
      this.open()
      eventStack.sub('click', this.closeOnDocumentClick)
      eventStack.sub('keydown', [
        this.closeOnEscape,
        this.moveSelectionOnKeyDown,
        this.selectItemOnEnter,
      ])
    } else if (prevState.open && !this.state.open) {
      debug('search closed')
      this.close()
      eventStack.unsub('click', this.closeOnDocumentClick)
      eventStack.unsub('keydown', [
        this.closeOnEscape,
        this.moveSelectionOnKeyDown,
        this.selectItemOnEnter,
      ])
    }
  }

  componentWillUnmount() {
    debug('componentWillUnmount()')

    eventStack.unsub('click', this.closeOnDocumentClick)
    eventStack.unsub('keydown', [
      this.closeOnEscape,
      this.moveSelectionOnKeyDown,
      this.selectItemOnEnter,
    ])
  }

  // ----------------------------------------
  // Document Event Handlers
  // ----------------------------------------

  handleResultSelect = (e, result) => {
    debug('handleResultSelect()')
    debug(result)

    _.invoke(this.props, 'onResultSelect', e, { ...this.props, result })
  }

  handleSelectionChange = (e) => {
    debug('handleSelectionChange()')

    const result = this.getSelectedResult()
    _.invoke(this.props, 'onSelectionChange', e, { ...this.props, result })
  }

  closeOnEscape = (e) => {
    if (keyboardKey.getCode(e) !== keyboardKey.Escape) return
    e.preventDefault()
    this.close()
  }

  moveSelectionOnKeyDown = (e) => {
    debug('moveSelectionOnKeyDown()')
    debug(keyboardKey.getKey(e))
    switch (keyboardKey.getCode(e)) {
      case keyboardKey.ArrowDown:
        e.preventDefault()
        this.moveSelectionBy(e, 1)
        break
      case keyboardKey.ArrowUp:
        e.preventDefault()
        this.moveSelectionBy(e, -1)
        break
      default:
        break
    }
  }

  selectItemOnEnter = (e) => {
    debug('selectItemOnEnter()')
    debug(keyboardKey.getKey(e))
    if (keyboardKey.getCode(e) !== keyboardKey.Enter) return

    const result = this.getSelectedResult()

    // prevent selecting null if there was no selected item value
    if (!result) return

    e.preventDefault()

    // notify the onResultSelect prop that the user is trying to change value
    this.setValue(result.title)
    this.handleResultSelect(e, result)
    this.close()
  }

  closeOnDocumentClick = (e) => {
    debug('closeOnDocumentClick()')
    debug(e)
    this.close()
  }

  // ----------------------------------------
  // Component Event Handlers
  // ----------------------------------------

  handleMouseDown = (e) => {
    debug('handleMouseDown()')

    this.isMouseDown = true
    _.invoke(this.props, 'onMouseDown', e, this.props)
    eventStack.sub('mouseup', this.handleDocumentMouseUp)
  }

  handleDocumentMouseUp = () => {
    debug('handleDocumentMouseUp()')

    this.isMouseDown = false
    eventStack.unsub('mouseup', this.handleDocumentMouseUp)
  }

  handleInputClick = (e) => {
    debug('handleInputClick()', e)

    // prevent closeOnDocumentClick()
    e.nativeEvent.stopImmediatePropagation()

    this.tryOpen()
  }

  handleItemClick = (e, { id }) => {
    debug('handleItemClick()')
    debug(id)
    const result = this.getSelectedResult(id)

    // prevent closeOnDocumentClick()
    e.nativeEvent.stopImmediatePropagation()

    // notify the onResultSelect prop that the user is trying to change value
    this.setValue(result.title)
    this.handleResultSelect(e, result)
    this.close()
  }

  handleItemMouseDown = (e) => {
    debug('handleItemMouseDown()')

    // Heads up! We should prevent default to prevent blur events.
    // https://github.com/Semantic-Org/Semantic-UI-React/issues/3298
    e.preventDefault()
  }

  handleFocus = (e) => {
    debug('handleFocus()')

    _.invoke(this.props, 'onFocus', e, this.props)
    this.setState({ focus: true })
  }

  handleBlur = (e) => {
    debug('handleBlur()')

    _.invoke(this.props, 'onBlur', e, this.props)
    this.setState({ focus: false })
  }

  handleSearchChange = (e) => {
    debug('handleSearchChange()')
    debug(e.target.value)
    // prevent propagating to this.props.onChange()
    e.stopPropagation()
    const { minCharacters } = this.props
    const { open } = this.state
    const newQuery = e.target.value

    _.invoke(this.props, 'onSearchChange', e, { ...this.props, value: newQuery })

    // open search dropdown on search query
    if (newQuery.length < minCharacters) {
      this.close()
    } else if (!open) {
      this.tryOpen(newQuery)
    }

    this.setValue(newQuery)
  }

  // ----------------------------------------
  // Getters
  // ----------------------------------------

  getFlattenedResults = () => {
    const { category, results } = this.props

    return !category
      ? results
      : _.reduce(results, (memo, categoryData) => memo.concat(categoryData.results), [])
  }

  getSelectedResult = (index = this.state.selectedIndex) => {
    const results = this.getFlattenedResults()
    return _.get(results, index)
  }

  // ----------------------------------------
  // Setters
  // ----------------------------------------

  setValue = (value) => {
    debug('setValue()')
    debug('value', value)

    const { selectFirstResult } = this.props

    this.setState({ value, selectedIndex: selectFirstResult ? 0 : -1 })
  }

  moveSelectionBy = (e, offset) => {
    debug('moveSelectionBy()')
    debug(`offset: ${offset}`)
    const { selectedIndex } = this.state

    const results = this.getFlattenedResults()
    const lastIndex = results.length - 1

    // next is after last, wrap to beginning
    // next is before first, wrap to end
    let nextIndex = selectedIndex + offset
    if (nextIndex > lastIndex) nextIndex = 0
    else if (nextIndex < 0) nextIndex = lastIndex

    this.setState({ selectedIndex: nextIndex })
    this.scrollSelectedItemIntoView()
    this.handleSelectionChange(e)
  }

  // ----------------------------------------
  // Behavior
  // ----------------------------------------

  scrollSelectedItemIntoView = () => {
    debug('scrollSelectedItemIntoView()')
    // Do not access document when server side rendering
    if (!isBrowser()) return
    const menu = document.querySelector('.ui.search.active.visible .results.visible')
    if (!menu) return
    debug(`menu (results): ${menu}`)
    const item = menu.querySelector('.result.active')
    if (!item) return
    debug(`menu (results): ${menu}`)
    debug(`item (result): ${item}`)
    const isOutOfUpperView = item.offsetTop < menu.scrollTop
    const isOutOfLowerView = item.offsetTop + item.clientHeight > menu.scrollTop + menu.clientHeight

    if (isOutOfUpperView) {
      menu.scrollTop = item.offsetTop
    } else if (isOutOfLowerView) {
      menu.scrollTop = item.offsetTop + item.clientHeight - menu.clientHeight
    }
  }

  // Open if the current value is greater than the minCharacters prop
  tryOpen = (currentValue = this.state.value) => {
    debug('open()')

    const { minCharacters } = this.props
    if (currentValue.length < minCharacters) return

    this.open()
  }

  open = () => {
    debug('open()')
    this.setState({ open: true })
  }

  close = () => {
    debug('close()')
    this.setState({ open: false })
  }

  // ----------------------------------------
  // Render
  // ----------------------------------------

  renderSearchInput = (rest) => {
    const { icon, input } = this.props
    const { value } = this.state

    return Input.create(input, {
      autoGenerateKey: false,
      defaultProps: {
        ...rest,
        autoComplete: 'off',
        icon,
        onChange: this.handleSearchChange,
        onClick: this.handleInputClick,
        tabIndex: '0',
        value,
      },
      // Nested shorthand props need special treatment to survive the shallow merge
      overrideProps: overrideSearchInputProps,
    })
  }

  renderNoResults = () => {
    const { noResultsDescription, noResultsMessage } = this.props

    return (
      <div className='message empty'>
        <div className='header'>{noResultsMessage}</div>
        {noResultsDescription && <div className='description'>{noResultsDescription}</div>}
      </div>
    )
  }

  /**
   * Offset is needed for determining the active item for results within a
   * category. Since the index is reset to 0 for each new category, an offset
   * must be passed in.
   */
  renderResult = ({ childKey, ...result }, index, _array, offset = 0) => {
    const { resultRenderer } = this.props
    const { selectedIndex } = this.state
    const offsetIndex = index + offset

    return (
      <SearchResult
        key={childKey || result.id || result.title}
        active={selectedIndex === offsetIndex}
        onClick={this.handleItemClick}
        onMouseDown={this.handleItemMouseDown}
        renderer={resultRenderer}
        {...result}
        id={offsetIndex} // Used to lookup the result on item click
      />
    )
  }

  renderResults = () => {
    const { results } = this.props

    return _.map(results, this.renderResult)
  }

  renderCategories = () => {
    const { categoryLayoutRenderer, categoryRenderer, results: categories } = this.props
    const { selectedIndex } = this.state

    let count = 0

    return _.map(categories, ({ childKey, ...category }) => {
      const categoryProps = {
        key: childKey || category.name,
        active: _.inRange(selectedIndex, count, count + category.results.length),
        layoutRenderer: categoryLayoutRenderer,
        renderer: categoryRenderer,
        ...category,
      }
      const renderFn = _.partialRight(this.renderResult, count)

      count += category.results.length

      return <SearchCategory {...categoryProps}>{category.results.map(renderFn)}</SearchCategory>
    })
  }

  renderMenuContent = () => {
    const { category, showNoResults, results } = this.props

    if (_.isEmpty(results)) {
      return showNoResults ? this.renderNoResults() : null
    }

    return category ? this.renderCategories() : this.renderResults()
  }

  renderResultsMenu = () => {
    const { open } = this.state
    const resultsClasses = open ? 'visible' : ''
    const menuContent = this.renderMenuContent()

    if (!menuContent) return

    return <SearchResults className={resultsClasses}>{menuContent}</SearchResults>
  }

  render() {
    debug('render()')
    debug('props', this.props)
    debug('state', this.state)
    const { searchClasses, focus, open } = this.state

    const { aligned, category, className, fluid, loading, size } = this.props

    // Classes
    const classes = cx(
      'ui',
      open && 'active visible',
      size,
      searchClasses,
      useKeyOnly(category, 'category'),
      useKeyOnly(focus, 'focus'),
      useKeyOnly(fluid, 'fluid'),
      useKeyOnly(loading, 'loading'),
      useValueAndKey(aligned, 'aligned'),
      'search',
      className,
    )
    const unhandled = getUnhandledProps(Search, this.props)
    const ElementType = getElementType(Search, this.props)
    const [htmlInputProps, rest] = partitionHTMLProps(unhandled, {
      htmlProps: htmlInputAttrs,
    })

    return (
      <ElementType
        {...rest}
        className={classes}
        onBlur={this.handleBlur}
        onFocus={this.handleFocus}
        onMouseDown={this.handleMouseDown}
      >
        {this.renderSearchInput(htmlInputProps)}
        {this.renderResultsMenu()}
      </ElementType>
    )
  }
}

Search.propTypes = {
  /** An element type to render as (string or function). */
  as: PropTypes.elementType,

  // ------------------------------------
  // Behavior
  // ------------------------------------

  /** Initial value of open. */
  defaultOpen: PropTypes.bool,

  /** Initial value. */
  defaultValue: PropTypes.string,

  /** Shorthand for Icon. */
  icon: PropTypes.oneOfType([PropTypes.node, PropTypes.object]),

  /** Minimum characters to query for results */
  minCharacters: PropTypes.number,

  /** Additional text for "No Results" message with less emphasis. */
  noResultsDescription: PropTypes.node,

  /** Message to display when there are no results. */
  noResultsMessage: PropTypes.node,

  /** Controls whether or not the results menu is displayed. */
  open: PropTypes.bool,

  /**
   * One of:
   * - array of Search.Result props e.g. `{ title: '', description: '' }` or
   * - object of categories e.g. `{ name: '', results: [{ title: '', description: '' }]`
   */
  results: PropTypes.oneOfType([
    PropTypes.arrayOf(PropTypes.shape(SearchResult.propTypes)),
    PropTypes.shape(SearchCategory.propTypes),
  ]),

  /** Whether the search should automatically select the first result after searching. */
  selectFirstResult: PropTypes.bool,

  /** Whether a "no results" message should be shown if no results are found. */
  showNoResults: PropTypes.bool,

  /** Current value of the search input. Creates a controlled component. */
  value: PropTypes.string,

  // ------------------------------------
  // Rendering
  // ------------------------------------

  /**
   * Renders the SearchCategory layout.
   *
   * @param {object} categoryContent - The Renderable SearchCategory contents.
   * @param {object} resultsContent - The Renderable SearchResult contents.
   * @returns {*} - Renderable SearchCategory layout.
   */
  categoryLayoutRenderer: PropTypes.func,

  /**
   * Renders the SearchCategory contents.
   *
   * @param {object} props - The SearchCategory props object.
   * @returns {*} - Renderable SearchCategory contents.
   */
  categoryRenderer: PropTypes.func,

  /**
   * Renders the SearchResult contents.
   *
   * @param {object} props - The SearchResult props object.
   * @returns {*} - Renderable SearchResult contents.
   */
  resultRenderer: PropTypes.func,

  // ------------------------------------
  // Callbacks
  // ------------------------------------

  /**
   * Called on blur.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props.
   */
  onBlur: PropTypes.func,

  /**
   * Called on focus.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props.
   */
  onFocus: PropTypes.func,

  /**
   * Called on mousedown.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props.
   */
  onMouseDown: PropTypes.func,

  /**
   * Called when a result is selected.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props.
   */
  onResultSelect: PropTypes.func,

  /**
   * Called on search input change.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props, includes current value of search input.
   */
  onSearchChange: PropTypes.func,

  /**
   * Called when the active selection index is changed.
   *
   * @param {SyntheticEvent} event - React's original SyntheticEvent.
   * @param {object} data - All props.
   */
  onSelectionChange: PropTypes.func,

  // ------------------------------------
  // Style
  // ------------------------------------

  /** A search can have its results aligned to its left or right container edge. */
  aligned: PropTypes.string,

  /** A search can display results from remote content ordered by categories. */
  category: PropTypes.bool,

  /** Additional classes. */
  className: PropTypes.string,

  /** A search can have its results take up the width of its container. */
  fluid: PropTypes.bool,

  /** Shorthand for input element. */
  input: customPropTypes.itemShorthand,

  /** A search can show a loading indicator. */
  loading: PropTypes.bool,

  /** A search can have different sizes. */
  size: PropTypes.oneOf(_.without(SUI.SIZES, 'medium')),
}

Search.defaultProps = {
  icon: 'search',
  input: 'text',
  minCharacters: 1,
  noResultsMessage: 'No results found.',
  showNoResults: true,
}

Search.autoControlledProps = ['open', 'value']

Search.Category = SearchCategory
Search.Result = SearchResult
Search.Results = SearchResults