var Imap = require('node-imap'),
    inspect = require('util').inspect;
var fs      = require('fs');
var base64  = require('base64-stream');
const {simpleParser} = require('mailparser');

var imap = new Imap({
    user: "info@federspiel.tech",
    password: "fpGUpbQG34",
    host: "imap.strato.de", //this may differ if you are using some other mail services like yahoo
    port: 993,
    tls: true,
    connTimeout: 10000, // Default by node-imap
    authTimeout: 5000, // Default by node-imap,
    debug: null, // Or your custom function with only one incoming argument. Default: null
    tlsOptions: { rejectUnauthorized: false },
    mailbox: "INBOX", // mailbox to monitor
    searchFilter: ["UNSEEN", "FLAGGED"], // the search filter being used after an IDLE notification has been retrieved
    markSeen: true, // all fetched email willbe marked as seen and not fetched next time
    fetchUnreadOnStart: true, // use it only if you want to get all unread email on lib start. Default is `false`,
    mailParserOptions: { streamAttachments: true }, // options to be passed to mailParser lib.
    attachments: true, // download attachments as they are encountered to the project directory
    attachmentOptions: { directory: "attachments/" } // specify a download directory for attachments
});

function openInbox(cb) {
    imap.openBox('INBOX', false, cb);
}

let email_array = [];

imap.once('ready', function() {
    console.log("start open inbox");
    try{
        openInbox(function (err, box) {
            imap.search([ 'UNSEEN', ['SINCE', "1 January 2023"] ], function(err, results) {
                if(!results || !results.length){
                    console.log("The server didn't find any emails matching the specified criteria")
                    imap.end();return;
                }

                var f = imap.fetch(results,{ //you can set amount range like '1:2' or 'results' for all results
                    bodies: '',
                    struct: true
                })

                f.on('message', function(msg, seqno) {
                    console.log('Message #%d', seqno);
                    var prefix = '(#' + seqno + ') ';
                    msg.on('body', function(stream, info) {
                        //Retrieve the 'from' header and buffer the entire body of the newest message:
                        if (info.which === 'TEXT')

                            var buffer = '', count = 0;

                        stream.on('data', async function(chunk) {
                            count += chunk.length;
                            buffer += chunk.toString('utf8');
                        });

                        stream.once('end', async function() {
                            let attach = null
                            //console.log((await simpleParser(buffer))) -> to see entire data of email

                            if(((await simpleParser(buffer)).attachments).length != 0) {
                                attach = (await simpleParser(buffer)).attachments[0].content //to get attachments
                                let file = (await simpleParser(buffer)).attachments[0]
                                fs.writeFile(file.filename,file.content, "binary", (err) => {
                                    if(!err) console.log("Success")
                                })
                            }

                            if (info.which !== 'TEXT'){
                                dataheader = Imap.parseHeader(buffer)

                                //start -> set data, that you want to save on your DB
                                let emails_data = {
                                    "date": dataheader.date[0],
                                    "subject": dataheader.subject[0],
                                    "from": dataheader.from[0],
                                    "to": dataheader.to[0],
                                    "content": (await simpleParser(buffer)).text,
                                    "attachment": attach
                                }
                                console.log(emails_data)
                                //end -> set data

                                email_array.push(emails_data)
                            }
                            else
                                console.log(prefix + 'Body [%s] Finished', inspect(info.which));
                        });
                    });

                    //mark attributes email as read
                    msg.once('attributes', function(attrs) {
                        let uid = attrs.uid;
                        imap.addFlags(uid, ['\\Seen'], function (err) {
                            if (err) {
                                console.log(err);
                            } else {
                                console.log("Done, marked email as read!")
                            }
                        });
                    });
                    msg.once('end', function() {
                        console.log(prefix + 'Finished');
                    });
                });

                f.once('error', function(err) {
                    console.log('Fetch error: ' + err);
                });

                f.once('end', function() {
                    console.log('Done fetching all messages!');
                    imap.end();
                });

            })
        });}  catch (err){
        console.log("Error when request open inbox mail",err)
    }
});

imap.once('error', function(err) {
    console.log("Error when connection to IMAP", err);
});

imap.once('close', function() {
    console.log('Connection ended');
});

imap.connect();

return new Promise((resolve, reject) => {
    imap.once('close', async function () { //maybe, someone asking whether to use end or close and the author of the module says that close is always emitted so you should use that.
        resolve(email_array);
    });
})


console.log(email_array)