emoji-mart-lazyload/src/components/category.js

import React from 'react'
import PropTypes from 'prop-types'

import frequently from '../utils/frequently'
import { getData } from '../utils'
import { Emoji } from '.'

export default class Category extends React.Component {
  constructor(props) {
    super(props)

    this.setContainerRef = this.setContainerRef.bind(this)
    this.setLabelRef = this.setLabelRef.bind(this)
  }

  componentDidMount() {
    this.parent = this.container.parentNode

    this.margin = 0
    this.minMargin = 0

    this.memoizeSize()
  }

  shouldComponentUpdate(nextProps, nextState) {
    var {
        name,
        perLine,
        native,
        hasStickyPosition,
        emojis,
        emojiProps,
      } = this.props,
      { skin, size, set } = emojiProps,
      {
        perLine: nextPerLine,
        native: nextNative,
        hasStickyPosition: nextHasStickyPosition,
        emojis: nextEmojis,
        emojiProps: nextEmojiProps,
      } = nextProps,
      { skin: nextSkin, size: nextSize, set: nextSet } = nextEmojiProps,
      shouldUpdate = false

    if (name == 'Recent' && perLine != nextPerLine) {
      shouldUpdate = true
    }

    if (name == 'Search') {
      shouldUpdate = !(emojis == nextEmojis)
    }

    if (
      skin != nextSkin ||
      size != nextSize ||
      native != nextNative ||
      set != nextSet ||
      hasStickyPosition != nextHasStickyPosition
    ) {
      shouldUpdate = true
    }

    return shouldUpdate
  }

  memoizeSize() {
    var { top, height } = this.container.getBoundingClientRect()
    var { top: parentTop } = this.parent.getBoundingClientRect()
    var { height: labelHeight } = this.label.getBoundingClientRect()

    this.top = top - parentTop + this.parent.scrollTop

    if (height == 0) {
      this.maxMargin = 0
    } else {
      this.maxMargin = height - labelHeight
    }
  }

  handleScroll(scrollTop) {
    var margin = scrollTop - this.top
    margin = margin < this.minMargin ? this.minMargin : margin
    margin = margin > this.maxMargin ? this.maxMargin : margin

    if (margin == this.margin) return

    if (!this.props.hasStickyPosition) {
      this.label.style.top = `${margin}px`
    }

    this.margin = margin
    return true
  }

  getEmojis() {
    var { name, emojis, recent, perLine } = this.props

    if (name == 'Recent') {
      let { custom } = this.props
      let frequentlyUsed = recent || frequently.get(perLine)

      if (frequentlyUsed.length) {
        emojis = frequentlyUsed
          .map(id => {
            const emoji = custom.filter(e => e.id === id)[0]
            if (emoji) {
              return emoji
            }

            return id
          })
          .filter(id => !!getData(id))
      }

      if (emojis.length === 0 && frequentlyUsed.length > 0) {
        return null
      }
    }

    if (emojis) {
      emojis = emojis.slice(0)
    }

    return emojis
  }

  updateDisplay(display) {
    var emojis = this.getEmojis()

    if (!emojis) {
      return
    }

    this.container.style.display = display
  }

  setContainerRef(c) {
    this.container = c
  }

  setLabelRef(c) {
    this.label = c
  }

  render() {
    var { id, name, hasStickyPosition, emojiProps, i18n } = this.props,
      emojis = this.getEmojis(),
      labelStyles = {},
      labelSpanStyles = {},
      containerStyles = {}

    if (!emojis) {
      containerStyles = {
        display: 'none',
      }
    }

    if (!hasStickyPosition) {
      labelStyles = {
        height: 28,
      }

      labelSpanStyles = {
        position: 'absolute',
      }
    }

    return (
      <div
        ref={this.setContainerRef}
        className={`emoji-mart-category ${emojis && !emojis.length
          ? 'emoji-mart-no-results'
          : ''}`}
        style={containerStyles}
      >
        <div
          style={labelStyles}
          data-name={name}
          className="emoji-mart-category-label"
        >
          <span style={labelSpanStyles} ref={this.setLabelRef}>
            {i18n.categories[id]}
          </span>
        </div>

        {emojis && emojis.map(emoji => Emoji({ emoji: emoji, ...emojiProps }))}

        {emojis &&
          !emojis.length && (
            <div>
              <div>
                {Emoji({
                  ...emojiProps,
                  size: 38,
                  emoji: 'sleuth_or_spy',
                  onOver: null,
                  onLeave: null,
                  onClick: null,
                })}
              </div>

              <div className="emoji-mart-no-results-label">{i18n.notfound}</div>
            </div>
          )}
      </div>
    )
  }
}

Category.propTypes = {
  emojis: PropTypes.array,
  hasStickyPosition: PropTypes.bool,
  name: PropTypes.string.isRequired,
  native: PropTypes.bool.isRequired,
  perLine: PropTypes.number.isRequired,
  emojiProps: PropTypes.object.isRequired,
  recent: PropTypes.arrayOf(PropTypes.string),
}

Category.defaultProps = {
  emojis: [],
  hasStickyPosition: true,
}