const Discord = require("discord.js");
const TOKEN = require("./token.js");
const db = require("./db.js");
const RSSParser = require("rss-parser");
const interval = require("interval-promise");

const client = new Discord.Client();
const parser = new RSSParser();
const RSS_UPDATE_INTERVAL_MIN = 5;

async function checkFeeds() {
    let feeds = db.get("rssFeeds").value();
    let outlets = db.get("feedOutputs").value();
    for(let feedEntry of feeds) {
        let feed = await parser.parseURL(feedEntry.url);
        if(feed.items.length == 0)
            continue;
        feed.items.filter(i => i.isoDate > feedEntry.lastUpdate).forEach(item => {
            outlets.forEach(ch => {
                client.channels.get(ch).send(`**${item.title}**\nPosted by ${item.creator}\n${item.link}`);
            });
        });
        db.get("rssFeeds").find({ url: feedEntry.url}).assign({lastUpdate: feed.items[0].isoDate}).write();
    }
}

function isAuthorised(member) {
    if (db.get("editors.users").includes(member.id).value())
        return true;
    if (db.get("editors.roles").intersectionWith(member.roles.keyArray()).isEmpty().value())
        return false;
    return true;
}

const commands = {
    "make guide": msg => {
        if (!isAuthorised(msg.member)) return;
        let content = msg.content.substring(msg.content.indexOf("make guide") + "make guide ".length);
        let guideName = content.substring(0, content.indexOf("\n")).trim();
        let guideContent = content.substring(content.indexOf("\n")).trim();

        let guide = db.get("guides").find({ name: guideName });

        if (!guide.isUndefined().value()) {
            guide.assign({ content: guideContent }).write();
        } else {
            db.get("guides")
                .push({
                    name: guideName,
                    content: guideContent
                })
                .write();
        }

        msg.channel.send(
            `${msg.author.toString()} Added/updated "${guideName}"!`
        );
    },
    "delete guide": (msg, s) => {
        if (!isAuthorised(msg.member)) return;
        let guideName = s.substring("delete guide ".length).trim();
        let val = db.get("guides").find({ name: guideName });

        if (val.isUndefined().value()) {
            msg.channel.send(`${msg.author.toString()} No guide "${guideName}"!`);
            return;
        }

        db.get("guides")
            .remove({ name: guideName })
            .write();
        msg.channel.send(
            `${msg.author.toString()} Removed guide "${guideName}!"`
        );
    },
    help: msg => {
        let guides = db
            .get("guides")
            .map(g => g.name)
            .reduce((p, c) => `${p}\n${c}`, "")
            .value();
        msg.channel.send(
            `Hello! I am NoctBot! I have answers for the most common C(O)M-related questions.\nJust ping me with one of the following keywords:\n\`\`\`${guides}\`\`\``
        );
    }
};

client.on("ready", () => {
    console.log("Ready!");
    client.user.setActivity("@NoctBot help", { type: "PLAYING" });
    interval(checkFeeds, RSS_UPDATE_INTERVAL_MIN * 60 * 1000);
});

client.on("message", m => {
    if (m.author.id == client.user.id || m.mentions.users.size == 0) return;

    if (!db.get("reactableMentionedUsers").intersectionWith(m.mentions.users.map(u => u.id)).isEmpty().value()) {
        const emoteId = db
            .get("emotes")
            .get("angery")
            .randomElement()
            .value();
        m.react(client.emojis.find(e => e.id == emoteId));
        return;
    }

    if (m.mentions.users.first().id == client.user.id) {
        let content = m.cleanContent.trim();
        if(content.startsWith(`@${client.user.username}`)) {
            content = content
                .substring(`@${client.user.username} `.length);
            let lowerCaseContent = content.toLowerCase().trim();
            for (let c in commands) {
                if (lowerCaseContent.startsWith(c)) {
                    commands[c](m, content);
                    return;
                }
            }

            if (lowerCaseContent.length > 0) {
                let parts = lowerCaseContent.trim().split(" ");
                let guide = db
                    .get("guides")
                    .map(g => Object.assign({parts: g.name.toLowerCase().split(" ")}, g))
                    .sortBy(g => g.parts.length)
                    .maxBy(k => db._.intersection(parts, k.parts).length)
                    .value();
                let hits =
                    guide !== undefined &&
                    db._.intersection(guide.name.toLowerCase().split(" "), parts).length > 0;
                if (hits) {
                    m.channel.send(guide.content);
                    return;
                }
            }
        }

        let emoteType = "angery";
        if(db.get("specialUsers").includes(m.author.id).value())
            emoteType = "hug";
        else if(db.get("bigUsers").includes(m.author.id).value())
            emoteType = "big";
        else if(db.get("dedUsers").includes(m.author.id).value())
            emoteType = "ded";

        const id = db
            .get("emotes")
            .get(emoteType)
            .randomElement()
            .value();
        m.channel.send(client.emojis.find(e => e.id == id).toString());
    } else if (m.content.includes("Noct")) {
        m.channel.send(
            client.emojis.find(e => e.name == "mukuNeighWaaaaaa").toString()
        );
    }
});

client.login(TOKEN);