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

import algoliasearch from 'algoliasearch/lite';
import { useHotkeys } from 'react-hotkeys-hook'
import { InstantSearch, connectHits, connectHighlight, connectSearchBox } from 'react-instantsearch-dom'
import config from 'site/algolia.config.mjs'

const searchClient = algoliasearch(config.algolia.app, config.algolia.key)

const Hits = props => {

  // When we hit enter in the text field, we want to navigate to the result
  // which means we must make the result links available in the input somehow
  // so let's stuff them in a data attribute
  const links = props.hits.map(hit => hit.page)
  props.input.current.setAttribute('data-links', JSON.stringify(links))

  return props.hits.map((hit, index) => (
    <Hit
      key={hit.page}
      {...props}
      hit={hit}
      index={index}
      len={props.hits.length}
      activeLink={links[props.active]}
    />
  ))
}

const CustomHits = connectHits(Hits);

const Highlight = ({ highlight, attribute, hit, snippet=false }) => {
  const parsedHit = highlight({
    highlightProperty: snippet ? '_snippetResult' : '_highlightResult',
    attribute,
    hit,
  });

  return parsedHit.map((part, index) => part.isHighlighted
    ? <mark className="text-base-content bg-secondary-focus bg-opacity-30" key={index}>{part.value}</mark>
    : <span key={index}>{part.value}</span>
  )
}

const CustomHighlight = connectHighlight(Highlight);

const Hit = props => (
  <div
    className={`
      px-2 py-1 ounded mt-1
      text-base text-base-content
      sm:rounded
      lg:px-4 lg:py-2
      hover:bg-secondary hover:bg-opacity-10 hover:text-base-content
      ${props.index === props.active
        ? 'bg-secondary bg-opacity-30'
        : 'bg-base-300 bg-opacity-10'
        }
    `}
  >
    <Link href={props.hit.page}>
      <a href={props.hit.page} className="flex flex-row justify-between gap-2">
        <span className="text-base sm:text-xl font-bold leading-5">
          {props.hit._highlightResult?.title
            ? <CustomHighlight hit={props.hit} attribute='title' />
            : props.hit.title
          }
        </span>
        <span className="text-xs pt-0.5 sm:text-base sm:pt-1 font-bold uppercase">{props.hit.page.split('/')[1]}</span>
      </a>
    </Link>
    {props.hit._snippetResult?.body && (
      <Link href={props.hit.page}>
        <a href={props.hit.page} className="text-sm sm:text-base block py-1">
          <CustomHighlight hit={props.hit} attribute='body' snippet />
        </a>
      </Link>
    )}
    {props.hit?._highlightResult?.page && (
      <Link href={props.hit.page}>
        <a href={props.hit.page} className="text-xs sm:text-sm block opacity-70">
          <CustomHighlight hit={props.hit} attribute='page' />
        </a>
      </Link>
    )}
  </div>
)

// We use this for trapping ctrl-c
const handleInputKeydown = (evt, setSearch, setActive, active, router) => {
  if (evt.key === 'Escape') setSearch(false)
  if (evt.key === 'ArrowDown') setActive(act => act + 1)
  if (evt.key === 'ArrowUp') setActive(act => act - 1)
  if (evt.key === 'Enter') {
    // Trigger navigation
    if (evt.target?.dataset?.links) {
      router.push(JSON.parse(evt.target.dataset.links)[active])
      setSearch(false)
    }
  }
}

const SearchBox = props => {

  const input = useRef(null)
  const router = useRouter()
  useHotkeys('ctrl+x', () => {
    input.current.value = ''
  })
  if (input.current && props.active < 0) input.current.focus()

  const { currentRefinement, refine, setSearch, setActive } = props

  return (
    <div className="py-8">
      <form noValidate action="" role="search" onSubmit={(evt) => evt.preventDefault()}>
        <div className="form-control">
          <div className="relative">
            <input
              ref={input}
              type="search"
              autoFocus={true}
              value={currentRefinement}
              onChange={event => refine(event.currentTarget.value)}
              onKeyDown={(evt) => handleInputKeydown(evt, setSearch, setActive, props.active, router)}
              className="input lg:input-lg input-bordered input-neutral w-full pr-16"
              placeholder='Type to search'
            />
            <button
              className="absolute right-0 top-0 rounded-l-none btn btn-neutral lg:btn-lg"
              onClick={() => props.setSearch(false)}
            >X</button>
          </div>
          <label className="label hidden sm:block">
            <div className="label-text flex flex-row gap-4 justify-between">
              <div><b> Escape</b> to exit</div>
              <div><b> Up</b> or <b>Down</b> to select</div>
              <div><b> Enter</b> to navigate</div>
            </div>
          </label>
        </div>
        <div
          className="overscroll-auto overflow-y-auto mt-2"
          style={{maxHeight: 'calc(100vh - 10rem)'}}
        >
        {
          input.current
          && input.current.value.length > 0
          && <CustomHits hitComponent={Hit} {...props} input={input}/>
        }
        </div>
      </form>
      <div className={`
        bg-neutral text-neutral-content
        z-20 w-full mx-auto
        lg:bg-base-100 lg:border-base-200
        fixed bottom-0 left-0 border-t-2
        lg:hidden
      `}>
        <div className='px-4 py-0 flex flex-row w-full lg:py-2'>
          <button
            className={`btn btn-ghost btn-block`}
            onClick={() => props.setSearch(false)}
          >
            <span className='px-2 pt-2 pb-2'>Close Search</span>
          </button>
        </div>
      </div>
    </div>
  )
}

const CustomSearchBox = connectSearchBox(SearchBox);

const Search = props => {

  const [active, setActive] = useState(0)
  useHotkeys('esc', () => props.setSearch(false))
  useHotkeys('up', () => {
    if (active) setActive(act => act - 1)
  })
  useHotkeys('down', () => {
    setActive(act => act + 1)
  })
  useHotkeys('down', () => {
    console.log('enter', active)
  })

  const stateProps = {
    setSearch: props.setSearch,
    setMenu: props.setMenu,
    active, setActive
  }

  return (
    <InstantSearch indexName={config.algolia.index} searchClient={searchClient}>
      <CustomSearchBox {...stateProps}/>
    </InstantSearch>
  )
}

export default Search