lbry-desktop/ui/util/comments.js
saltrafael e5795baa10
own comments show first in controversial / best #5905 (#5939)
* own comments show first in controversial / best #5905

* workaround to place my recent comment at the top

* only most recent comment

* lint fix

Co-authored-by: Thomas Zarebczan <thomas.zarebczan@gmail.com>
2021-05-15 00:56:58 -04:00

93 lines
3 KiB
JavaScript

// @flow
import * as REACTION_TYPES from 'constants/reactions';
import { SORT_COMMENTS_NEW, SORT_COMMENTS_BEST, SORT_COMMENTS_CONTROVERSIAL } from 'constants/comment';
// Mostly taken from Reddit's sorting functions
// https://github.com/reddit-archive/reddit/blob/master/r2/r2/lib/db/_sorts.pyx
type SortProps = {
comments: ?Array<Comment>,
reactionsById: {},
sort: string,
isMyComment: string => boolean,
justCommented: boolean,
};
export function sortComments(sortProps: SortProps): Array<Comment> {
const { comments, reactionsById, sort, isMyComment, justCommented } = sortProps;
if (!comments) return [];
return comments.slice().sort((a: Comment, b: Comment) => {
if (a.is_pinned) {
return -1;
} else if (b.is_pinned) {
return 1;
}
if (sort === SORT_COMMENTS_NEW) return 0;
const aIsMine = isMyComment(a.channel_id);
const bIsMine = isMyComment(b.channel_id);
const aIsMyRecent = a.comment_id === comments[0].comment_id;
const bIsMyRecent = b.comment_id === comments[0].comment_id;
if (aIsMine && justCommented && aIsMyRecent) {
return -1;
} else if (bIsMine && justCommented && bIsMyRecent) {
return 1;
}
const aReactions = reactionsById[a.comment_id];
const bReactions = reactionsById[b.comment_id];
const aLikes = (aReactions && aReactions[REACTION_TYPES.LIKE]) || 0;
const aDislikes = (aReactions && aReactions[REACTION_TYPES.DISLIKE]) || 0;
const bLikes = (bReactions && bReactions[REACTION_TYPES.LIKE]) || 0;
const bDislikes = (bReactions && bReactions[REACTION_TYPES.DISLIKE]) || 0;
if (sort === SORT_COMMENTS_CONTROVERSIAL) {
if (aLikes === 0 && aDislikes === 0) {
return 1;
} else if (bLikes === 0 && bDislikes === 0) {
return -1;
}
const aMagnitude = aLikes + aDislikes;
const bMagnitude = bLikes + bDislikes;
const aBalance = aLikes > aDislikes ? aDislikes / aLikes : aLikes / aDislikes;
const bBalance = bLikes > bDislikes ? bDislikes / bLikes : bLikes / bDislikes;
return bMagnitude ** bBalance - aMagnitude ** aBalance;
}
if (sort === SORT_COMMENTS_BEST) {
const aN = aLikes + aDislikes;
const bN = bLikes + bDislikes;
if (aLikes === 0 && bLikes === 0 && (aDislikes || bDislikes)) {
return aDislikes - bDislikes;
} else if (aLikes === 0 && bLikes > 0) {
return 1;
} else if (bLikes === 0 && aLikes > 1) {
return -1;
}
const z = 1.281551565545; // 80% confidence
const aP = aLikes / aN;
const bP = bLikes / bN;
const aLeft = aP + (1 / (2 * aN)) * z * z;
const aRight = z * Math.sqrt((aP * (1 - aP)) / aN + (z * z) / (4 * aN * aN));
const aUnder = 1 + (1 / aN) * z * z;
const bLeft = bP + (1 / (2 * bN)) * z * z;
const bRight = z * Math.sqrt((bP * (1 - bP)) / bN + (z * z) / (4 * bN * bN));
const bUnder = 1 + (1 / bN) * z * z;
return (bLeft - bRight) / bUnder - (aLeft - aRight) / aUnder;
}
return 0;
});
}