import { Form, MarkdownInput, SubmitButton } from '../components/form'
import { gql, useMutation } from '@apollo/client'
import styles from './reply.module.css'
import { COMMENTS } from '../fragments/comments'
import { useMe } from './me'
import { useEffect, useState, useRef, useCallback } from 'react'
import Link from 'next/link'
import FeeButton from './fee-button'
import { commentsViewedAfterComment } from '../lib/new-comments'
import { commentSchema } from '../lib/validate'
import Info from './info'
import { useInvoiceable } from './invoice'

export function ReplyOnAnotherPage ({ parentId }) {
  return (
    <Link href={`/items/${parentId}`} className={`${styles.replyButtons} text-muted`}>
      reply on another page
    </Link>
  )
}

function FreebieDialog () {
  return (
    <div className='text-muted'>
      you have no sats, so this one is on us
      <Info>
        <ul className='fw-bold'>
          <li>Free comments have limited visibility and are listed at the bottom of the comment section until other stackers zap them.</li>
          <li>Free comments will not cover comments that cost more than 1 sat.</li>
          <li>To get fully visibile and unrestricted comments right away, fund your account with a few sats or earn some on Stacker News.</li>
        </ul>
      </Info>
    </div>
  )
}

export default function Reply ({ item, onSuccess, replyOpen, children, placeholder }) {
  const [reply, setReply] = useState(replyOpen)
  const me = useMe()
  const parentId = item.id

  useEffect(() => {
    setReply(replyOpen || !!window.localStorage.getItem('reply-' + parentId + '-' + 'text'))
  }, [])

  const [createComment] = useMutation(
    gql`
      ${COMMENTS}
      mutation createComment($text: String!, $parentId: ID!, $invoiceHash: String, $invoiceHmac: String) {
        createComment(text: $text, parentId: $parentId, invoiceHash: $invoiceHash, invoiceHmac: $invoiceHmac) {
          ...CommentFields
          comments {
            ...CommentsRecursive
          }
        }
      }`, {
      update (cache, { data: { createComment } }) {
        cache.modify({
          id: `Item:${parentId}`,
          fields: {
            comments (existingCommentRefs = []) {
              const newCommentRef = cache.writeFragment({
                data: createComment,
                fragment: COMMENTS,
                fragmentName: 'CommentsRecursive'
              })
              return [newCommentRef, ...existingCommentRefs]
            }
          }
        })

        const ancestors = item.path.split('.')

        // update all ancestors
        ancestors.forEach(id => {
          cache.modify({
            id: `Item:${id}`,
            fields: {
              ncomments (existingNComments = 0) {
                return existingNComments + 1
              }
            }
          })
        })

        // so that we don't see indicator for our own comments, we record this comments as the latest time
        // but we also have record num comments, in case someone else commented when we did
        const root = ancestors[0]
        commentsViewedAfterComment(root, createComment.createdAt)
      }
    }
  )

  const submitComment = useCallback(
    async (_, values, parentId, resetForm, invoiceHash, invoiceHmac) => {
      const { error } = await createComment({ variables: { ...values, parentId, invoiceHash, invoiceHmac } })
      if (error) {
        throw new Error({ message: error.toString() })
      }
      resetForm({ text: '' })
      setReply(replyOpen || false)
    }, [createComment, setReply])

  const invoiceableCreateComment = useInvoiceable(submitComment)

  const replyInput = useRef(null)
  useEffect(() => {
    if (replyInput.current && reply && !replyOpen) replyInput.current.focus()
  }, [reply])

  return (
    <div>
      {replyOpen
        ? <div className={styles.replyButtons} />
        : (
          <div className={styles.replyButtons}>
            <div
              onClick={() => setReply(!reply)}
            >
              {reply ? 'cancel' : 'reply'}
            </div>
            {/* HACK if we need more items, we should probably do a comment toolbar */}
            {children}
          </div>)}
      {reply &&
        <div className={styles.reply}>
          <Form
            initial={{
              text: ''
            }}
            schema={commentSchema}
            onSubmit={async ({ cost, ...values }, { resetForm }) => {
              await invoiceableCreateComment(cost, values, parentId, resetForm)
            }}
            storageKeyPrefix={'reply-' + parentId}
          >
            <MarkdownInput
              name='text'
              minRows={6}
              autoFocus={!replyOpen}
              required
              placeholder={placeholder}
              hint={me?.sats < 1 && <FreebieDialog />}
              innerRef={replyInput}
            />
            {reply &&
              <div className='mt-1'>
                <FeeButton
                  baseFee={1} parentId={parentId} text='reply'
                  ChildButton={SubmitButton} variant='secondary' alwaysShow
                />
              </div>}
          </Form>
        </div>}
    </div>
  )
}

export function ReplySkeleton () {
  return (
    <div className={`${styles.reply} ${styles.skeleton}`}>
      <div className={`${styles.input} clouds`} />
      <div className={`${styles.button} clouds`} />
    </div>
  )
}