NotionNext/themes/Medium/components/SearchInput.js

import { useRouter } from 'next/router'
import { useImperativeHandle, useRef, useState } from 'react'

const SearchInput = ({ currentTag, currentSearch, cRef, className }) => {
  const [searchKey, setSearchKey] = useState(currentSearch || getSearchKey() || '')
  const [onLoading, setLoadingState] = useState(false)
  const router = useRouter()
  const searchInputRef = useRef()
  useImperativeHandle(cRef, () => {
    return {
      focus: () => {
        searchInputRef?.current?.focus()
      }
    }
  })

  const handleSearch = (key) => {
    if (key && key !== '') {
      setLoadingState(true)
      router.push({ pathname: '/search', query: { s: key } }).then(r => {
        setLoadingState(false)
      })
    } else {
      router.push({ pathname: '/' }).then(r => {
      })
    }
  }
  const handleKeyUp = (e) => {
    if (e.keyCode === 13) { // 回车
      handleSearch(searchInputRef.current.value)
    } else if (e.keyCode === 27) { // ESC
      cleanSearch()
    }
  }
  const cleanSearch = () => {
    searchInputRef.current.value = ''
    setSearchKey('')
  }

  const updateSearchKey = (val) => {
    setSearchKey(val)
  }

  return <div className={'flex w-full bg-gray-100 ' + className}>
    <input
      ref={searchInputRef}
      type='text'
      className={'w-full text-sm pl-2 transition focus:shadow-lg font-light leading-10 text-black bg-gray-100 dark:bg-gray-900 dark:text-white'}
      onKeyUp={handleKeyUp}
      onChange={e => updateSearchKey(e.target.value)}
      defaultValue={searchKey}
    />

    <div className='-ml-8 cursor-pointer dark:bg-gray-600 dark:hover:bg-gray-800 float-right items-center justify-center py-2'
      onClick={() => { handleSearch(searchKey) }}>
        <i className={`hover:text-black transform duration-200 text-gray-500 cursor-pointer fas ${onLoading ? 'fa-spinner animate-spin' : 'fa-search'} `} />
    </div>

    {(searchKey && searchKey.length &&
      <div className='-ml-12 cursor-pointer dark:bg-gray-600 dark:hover:bg-gray-800 float-right items-center justify-center py-2'>
        <i className='fas fa-times hover:text-black transform duration-200 text-gray-400 cursor-pointer' onClick={cleanSearch} />
      </div>
      )}
  </div>
}

function getSearchKey () {
  const router = useRouter()
  if (router.query && router.query.s) {
    return router.query.s
  }
  return null
}

export default SearchInput