import React, {useMemo, useState} from 'react'
import {observer} from 'mobx-react-lite'
import {StyleSheet, Text, View} from 'react-native'
import Clipboard from '@react-native-clipboard/clipboard'
import {AtUri} from '../../../third-party/uri'
import * as PostType from '../../../third-party/api/src/client/types/app/bsky/feed/post'
import {FontAwesomeIcon} from '@fortawesome/react-native-fontawesome'
import {FeedItemModel} from '../../../state/models/feed-view'
import {Link} from '../util/Link'
import {UserInfoText} from '../util/UserInfoText'
import {PostMeta} from '../util/PostMeta'
import {PostCtrls} from '../util/PostCtrls'
import {PostEmbeds} from '../util/PostEmbeds'
import {RichText} from '../util/RichText'
import * as Toast from '../util/Toast'
import {UserAvatar} from '../util/UserAvatar'
import {s, colors} from '../../lib/styles'
import {useStores} from '../../../state'

const TOP_REPLY_LINE_LENGTH = 12
const REPLYING_TO_LINE_LENGTH = 8

export const FeedItem = observer(function FeedItem({
  item,
}: {
  item: FeedItemModel
}) {
  const store = useStores()
  const [deleted, setDeleted] = useState(false)
  const record = item.record as unknown as PostType.Record
  const itemHref = useMemo(() => {
    const urip = new AtUri(item.uri)
    return `/profile/${item.author.handle}/post/${urip.rkey}`
  }, [item.uri, item.author.handle])
  const itemTitle = `Post by ${item.author.handle}`
  const authorHref = `/profile/${item.author.handle}`
  const replyAuthorDid = useMemo(() => {
    if (!record.reply) return ''
    const urip = new AtUri(record.reply.parent?.uri || record.reply.root.uri)
    return urip.hostname
  }, [record.reply])
  const replyHref = useMemo(() => {
    if (!record.reply) return ''
    const urip = new AtUri(record.reply.parent?.uri || record.reply.root.uri)
    return `/profile/${urip.hostname}/post/${urip.rkey}`
  }, [record.reply])

  const onPressReply = () => {
    store.shell.openComposer({
      replyTo: {
        uri: item.uri,
        cid: item.cid,
        text: item.record.text as string,
        author: {
          handle: item.author.handle,
          displayName: item.author.displayName,
        },
      },
    })
  }
  const onPressToggleRepost = () => {
    item
      .toggleRepost()
      .catch(e => console.error('Failed to toggle repost', record, e))
  }
  const onPressToggleUpvote = () => {
    item
      .toggleUpvote()
      .catch(e => console.error('Failed to toggle upvote', record, e))
  }
  const onCopyPostText = () => {
    Clipboard.setString(record.text)
    Toast.show('Copied to clipboard')
  }
  const onDeletePost = () => {
    item.delete().then(
      () => {
        setDeleted(true)
        Toast.show('Post deleted')
      },
      e => {
        console.error(e)
        Toast.show('Failed to delete post, please try again')
      },
    )
  }

  if (deleted) {
    return <View />
  }

  const outerStyles = [
    styles.outer,
    item._isThreadChild ? styles.outerNoTop : undefined,
    item._isThreadParent ? styles.outerNoBottom : undefined,
  ]
  return (
    <Link style={outerStyles} href={itemHref} title={itemTitle}>
      {item._isThreadChild && <View style={styles.topReplyLine} />}
      {item._isThreadParent && (
        <View
          style={[
            styles.bottomReplyLine,
            item._isThreadChild ? styles.bottomReplyLineSmallAvi : undefined,
          ]}
        />
      )}
      {item.repostedBy && (
        <Link
          style={styles.includeReason}
          href={`/profile/${item.repostedBy.handle}`}
          title={item.repostedBy.displayName || item.repostedBy.handle}>
          <FontAwesomeIcon icon="retweet" style={styles.includeReasonIcon} />
          <Text style={[s.gray4, s.bold, s.f13]}>
            Reposted by {item.repostedBy.displayName || item.repostedBy.handle}
          </Text>
        </Link>
      )}
      {item.trendedBy && (
        <Link
          style={styles.includeReason}
          href={`/profile/${item.trendedBy.handle}`}
          title={item.trendedBy.displayName || item.trendedBy.handle}>
          <FontAwesomeIcon
            icon="arrow-trend-up"
            style={styles.includeReasonIcon}
          />
          <Text style={[s.gray4, s.bold, s.f13]}>
            Trending with {item.trendedBy.displayName || item.trendedBy.handle}
          </Text>
        </Link>
      )}
      {item.additionalParentPost ? (
        <View style={styles.replyingTo}>
          <View style={styles.replyingToLine} />
          <View style={styles.replyingToAvatar}>
            <UserAvatar
              handle={item.additionalParentPost?.thread?.author.handle}
              displayName={
                item.additionalParentPost?.thread?.author.displayName
              }
              size={32}
            />
          </View>
          <View style={styles.replyingToTextContainer}>
            <Text style={styles.replyingToText} numberOfLines={2}>
              {item.additionalParentPost?.thread?.record.text}
            </Text>
          </View>
        </View>
      ) : undefined}
      <View style={styles.layout}>
        <View style={styles.layoutAvi}>
          <Link
            href={authorHref}
            title={item.author.handle}
            style={item._isThreadChild ? {marginLeft: 10} : undefined}>
            <UserAvatar
              size={item._isThreadChild ? 30 : 50}
              displayName={item.author.displayName}
              handle={item.author.handle}
            />
          </Link>
        </View>
        <View style={styles.layoutContent}>
          {!item._isThreadChild ? (
            <PostMeta
              itemHref={itemHref}
              itemTitle={itemTitle}
              authorHref={authorHref}
              authorHandle={item.author.handle}
              authorDisplayName={item.author.displayName}
              timestamp={item.indexedAt}
              isAuthor={item.author.did === store.me.did}
              onCopyPostText={onCopyPostText}
              onDeletePost={onDeletePost}
            />
          ) : undefined}
          {!item._isThreadChild && replyHref !== '' && (
            <View style={[s.flexRow, s.mb5, {alignItems: 'center'}]}>
              <Text style={[s.gray5, s.f15, s.mr2]}>Replying to</Text>
              <Link href={replyHref} title="Parent post">
                <UserInfoText
                  did={replyAuthorDid}
                  style={[s.f15, s.blue3]}
                  prefix="@"
                />
              </Link>
            </View>
          )}
          <View style={styles.postTextContainer}>
            <RichText
              text={record.text}
              entities={record.entities}
              style={styles.postText}
            />
          </View>
          <PostEmbeds entities={record.entities} style={{marginBottom: 10}} />
          <PostCtrls
            replyCount={item.replyCount}
            repostCount={item.repostCount}
            upvoteCount={item.upvoteCount}
            isReposted={!!item.myState.repost}
            isUpvoted={!!item.myState.upvote}
            onPressReply={onPressReply}
            onPressToggleRepost={onPressToggleRepost}
            onPressToggleUpvote={onPressToggleUpvote}
          />
        </View>
      </View>
    </Link>
  )
})

const styles = StyleSheet.create({
  outer: {
    borderRadius: 6,
    margin: 2,
    marginBottom: 0,
    backgroundColor: colors.white,
    padding: 10,
  },
  outerNoTop: {
    marginTop: 1,
    borderTopLeftRadius: 0,
    borderTopRightRadius: 0,
  },
  outerNoBottom: {
    marginBottom: 0,
    borderBottomLeftRadius: 0,
    borderBottomRightRadius: 0,
  },
  topReplyLine: {
    position: 'absolute',
    left: 34,
    top: -1 * TOP_REPLY_LINE_LENGTH + 10,
    height: TOP_REPLY_LINE_LENGTH,
    borderLeftWidth: 2,
    borderLeftColor: colors.gray2,
  },
  bottomReplyLine: {
    position: 'absolute',
    left: 34,
    top: 70,
    bottom: 0,
    borderLeftWidth: 2,
    borderLeftColor: colors.gray2,
  },
  bottomReplyLineSmallAvi: {
    top: 50,
  },
  includeReason: {
    flexDirection: 'row',
    paddingLeft: 60,
  },
  includeReasonIcon: {
    marginRight: 4,
    color: colors.gray4,
  },
  replyingToLine: {
    position: 'absolute',
    left: 24,
    bottom: -1 * REPLYING_TO_LINE_LENGTH + 6,
    height: REPLYING_TO_LINE_LENGTH,
    borderLeftWidth: 2,
    borderLeftColor: colors.gray2,
  },
  replyingTo: {
    flexDirection: 'row',
    backgroundColor: colors.white,
    paddingBottom: 8,
    paddingRight: 24,
  },
  replyingToAvatar: {
    marginLeft: 9,
    marginRight: 19,
    marginTop: 1,
  },
  replyingToTextContainer: {
    flex: 1,
    flexDirection: 'row',
    height: 34,
    alignItems: 'center',
  },
  replyingToText: {
    flex: 1,
    color: colors.gray5,
  },
  layout: {
    flexDirection: 'row',
  },
  layoutAvi: {
    width: 60,
    paddingTop: 5,
  },
  layoutContent: {
    flex: 1,
  },
  postTextContainer: {
    flexDirection: 'row',
    alignItems: 'center',
    flexWrap: 'wrap',
    paddingBottom: 8,
    minHeight: 36,
  },
  postText: {
    fontFamily: 'System',
    fontSize: 16,
    lineHeight: 20.8, // 1.3 of 16px
  },
})
