Function addReactionToThread

packages/utilities/src/reaction.ts:8–136

(
  thread: SerializedThread,
  {
    threadId,
    messageId,
    currentUser,
    type,
    active,
  }: {
    threadId: string;
    messageId: string;
    currentUser: SerializedUser | null;
    type: string;
    active: boolean;
  }
)

} from '@linen/types';

export function addReactionToThread(
  thread: SerializedThread,
  {
    threadId,
    messageId,
    currentUser,
    type,
    active,
  }: {
    threadId: string;
    messageId: string;
    currentUser: SerializedUser | null;
    type: string;
    active: boolean;
  }
): SerializedThread {
  if (!thread || !currentUser) {
    return thread;
  }
  if (thread.id === threadId) {
    return {
      ...thread,
      messages: thread.messages.map((message) => {
        if (message.id === messageId) {
          const reaction = message.reactions.find(
            (reaction) => reaction.type === type
          );

          if (!reaction) {
            return {
              ...message,
              reactions: [
                ...(message.reactions
                  .map((reaction) => {
                    if (
                      (type === ':thumbsup:' &&
                        reaction.type === ':thumbsdown:') ||
                      (type === ':thumbsdown:' &&
                        reaction.type === ':thumbsup:')
                    ) {
                      const userIds = reaction.users.map(({ id }) => id);
                      if (userIds.includes(currentUser.id)) {
                        if (reaction.count === 1) {
                          return null;
                        }
                        return {
                          ...reaction,
                          count: reaction.count - 1,
                          users: reaction.users.filter(
                            ({ id }) => id !== currentUser.id
                          ),
                        };
                      }
                    }
                    return reaction;
                  })
                  .filter(Boolean) as SerializedReaction[]),
                { type, count: 1, users: [currentUser] },