const { getMailbox, updateMailbox } = require("../../db/imap/imap");
const { logger } = require("../../system/Logger");
const { registerMessageInApp } = require("../saveMessage");
const { saveMessage } = require("../storeMessage");

class Box {
    constructor(_imap, _boxId, _boxName) {
        this.imap = _imap;
        this.boxName = _boxName;
        this.id = _boxId;
        this.box;
        this.init();
    }

    async init() {
        this.box = (await getMailbox(this.id))[0];

        const readOnly = true;
        this.imap.openBox(this.boxName, readOnly, (err, box) => {
            if (err) logger.error(err);
            this.sync(this.box.uidnext, box.uidnext);
        });
    }

    sync(savedUid, currentUid) {
        const promises = [];
        const mails = [];
        logger.log(`Syncing from ${savedUid} to ${currentUid} uid`);
        const f = this.imap.seq.fetch(`${savedUid}:${currentUid}`, {
            size: true,
            envelope: true,
        });

        f.on("message", (msg, seqno) => {
            msg.once("attributes", (attrs) => {
                mails.push(attrs);
                promises.push(saveMessage(attrs, this.id, this.imap));
            });
        });

        f.once("error", (err) => {
            logger.error("Fetch error: " + err);
        });

        f.once("end", async () => {
            let step = 20;
            for (let i = 0; i < promises.length; i += step) {
                for (let j = i; j < (i + step && promises.length); j++) {
                    console.log(j, promises.length, promises[j])
                    await new Promise((resolve, reject) => {
                        promises[j]
                            .then(async (res) => {
                                await registerMessageInApp(res, mails[j], this.id);
                                resolve();
                            })
                            .catch((err) => {
                                reject(err);
                            });
                    });
                }
                logger.log(`Saved messages ${i + step > promises.length ? promises.length : i + step}/${mails.length}`);
                updateMailbox(this.id, mails[i].uid);
            }
            // await Promise.all(promises).then(async (res) => {
            //     for (let i = 0; i < mails.length; i++) {
            //         logger.log(`Saved message ${i}/${mails.length}`);
            //     }
            // });
            updateMailbox(this.id, currentUid);
        });
    }
}

module.exports = {
    Box,
};