'use strict';

const config = require('config');
const util = require('util');
const fs = require('fs-extra');
const snoowrap = require('snoowrap');
const promiseFinally = require('promise.prototype.finally');

const reddit = new snoowrap(config.reddit.api);

const curatePosts = require('./curate/posts.js');
const curateUser = require('./curate/user.js');

const interpolate = require('./interpolate.js');

const attachContentInfo = require('./fetch/info.js');
const fetchContent = require('./fetch/content.js');

const save = require('./save/save.js');
const saveProfileDetails = require('./save/profileDetails.js');

promiseFinally.shim();

const args = require('./cli.js');

if(!(args.users && args.users.length) && !(args.posts && args.posts.length)) {
    return console.log('\x1b[31m%s\x1b[0m', 'Please supply at least one user with --user <user> or one post with --post <post-id>. See --help for more options.');
}

Promise.resolve().then(() => {
    if(args.users) {
        return getUserPosts(args.users);
    }
}).then((userPosts = []) => {
    if(args.posts) {
        return getPosts(args.posts).then(posts => posts.concat(userPosts));
    }

    return userPosts;
}).then(posts => {
    return curatePosts(posts).slice(0, args.limit);
}).then(posts => {
    return attachContentInfo(posts).then(info => fetchContent(posts));
}).catch(error => {
    return console.error(error);
});

function getUserPosts(users) {
    return users.reduce((chain, username) => {
        return chain.then(accPosts => {
            return reddit.getUser(username).fetch().then(curateUser).then(saveProfileDetails).then(user => ({user, accPosts}));
        }).then(({user, accPosts}) => {
            return reddit.getUser(username).getSubmissions({
                sort: args.sort,
                limit: Infinity
            }).then(posts => {
                return accPosts.concat(posts.map(post => {
                    post.user = user;

                    return post;
                }));
            });
        });
    }, Promise.resolve([]));
};

function getPosts(postIds) {
    return postIds.reduce((chain, postId) => {
        return chain.then(acc => {
            return reddit.getSubmission(postId).fetch().then(post => ({post, acc}));
        }).then(({post, acc}) => {
            if(acc.users[post.author.name]) {
                return {post, acc, user: acc.users[post.author.name]}
            }

            return reddit.getUser(post.author.name).fetch().then(curateUser).then(saveProfileDetails).then(user => ({post, acc, user}));
        }).then(({post, acc, user}) => {
            post.user = user;
            acc.posts.push(post);

            // keep track of users to prevent fetching one user multiple times
            acc.users[user.name] = user;

            return acc;
        });
    }, Promise.resolve({
        posts: [],
        users: {}
    })).then(({posts, users}) => {
        return posts;
    });
};