NodeBB/NodeBB

'use strict';

const topics = require('../../topics');
const privileges = require('../../privileges');
const meta = require('../../meta');
const utils = require('../../utils');
const social = require('../../social');

module.exports = function (SocketTopics) {
    SocketTopics.loadMore = async function (socket, data) {
        if (!data || !data.tid || !utils.isNumber(data.after) || parseInt(data.after, 10) < 0) {
            throw new Error('[[error:invalid-data]]');
        }

        const [userPrivileges, topicData] = await Promise.all([
            privileges.topics.get(data.tid, socket.uid),
            topics.getTopicData(data.tid),
        ]);

        if (!userPrivileges['topics:read'] || !privileges.topics.canViewDeletedScheduled(topicData, userPrivileges)) {
            throw new Error('[[error:no-privileges]]');
        }

        const set = data.topicPostSort === 'most_votes' ? `tid:${data.tid}:posts:votes` : `tid:${data.tid}:posts`;
        const reverse = data.topicPostSort === 'newest_to_oldest' || data.topicPostSort === 'most_votes';
        let start = Math.max(0, parseInt(data.after, 10));

        const infScrollPostsPerPage = Math.max(0, Math.min(
            meta.config.postsPerPage || 20,
            parseInt(data.count, 10) || meta.config.postsPerPage || 20
        ));

        if (parseInt(data.direction, 10) === -1) {
            start -= infScrollPostsPerPage;
        }

        let stop = start + infScrollPostsPerPage - 1;

        start = Math.max(0, start);
        stop = Math.max(0, stop);
        const [posts, postSharing] = await Promise.all([
            topics.getTopicPosts(topicData, set, start, stop, socket.uid, reverse),
            social.getActivePostSharing(),
        ]);

        topicData.posts = posts;
        topicData.privileges = userPrivileges;
        topicData.postSharing = postSharing;
        topicData['reputation:disabled'] = meta.config['reputation:disabled'] === 1;
        topicData['downvote:disabled'] = meta.config['downvote:disabled'] === 1;

        topics.modifyPostsByPrivilege(topicData, userPrivileges);
        return topicData;
    };
};