server.js

#!/usr/bin/env node

const process = require('process')
const yargs = require('yargs/yargs');
const { hideBin } = require('yargs/helpers');

const cliArguments = yargs(hideBin(process.argv))
    .option('ssl', {
        type: 'boolean',
        default: false,
        describe: 'Enables SSL'
    }).option('certPath', {
        type: 'string',
        default: 'certs/cert.pem',
        describe: 'Path to your certificate file.'
    }).option('keyPath', {
        type: 'string',
        default: 'certs/privkey.pem',
        describe: 'Path to your private key file.'
    }).argv;

// change all relative paths
process.chdir(__dirname)

const express = require('express');
const compression = require('compression');
const app = express();
app.use(compression());

const fs = require('fs');
const readline = require('readline');
const open = require('open');

const rimraf = require("rimraf");
const multer = require("multer");
const http = require("http");
const https = require('https');
const basicAuthMiddleware = require('./src/middleware/basicAuthMiddleware');
//const PNG = require('pngjs').PNG;
const extract = require('png-chunks-extract');
const encode = require('png-chunks-encode');
const PNGtext = require('png-chunk-text');

const jimp = require('jimp');
const path = require('path');
const sanitize = require('sanitize-filename');
const mime = require('mime-types');

const cookieParser = require('cookie-parser');
const crypto = require('crypto');
const ipaddr = require('ipaddr.js');
const json5 = require('json5');

const ExifReader = require('exifreader');
const exif = require('piexifjs');
const webp = require('webp-converter');

const config = require(path.join(__dirname, './config.conf'));
const server_port = process.env.SILLY_TAVERN_PORT || config.port;

const whitelistPath = path.join(__dirname, "./whitelist.txt");
let whitelist = config.whitelist;

if (fs.existsSync(whitelistPath)) {
    try {
        let whitelistTxt = fs.readFileSync(whitelistPath, 'utf-8');
        whitelist = whitelistTxt.split("\n").filter(ip => ip).map(ip => ip.trim());
    } catch (e) { }
}

const whitelistMode = config.whitelistMode;
const autorun = config.autorun && !cliArguments.ssl;
const enableExtensions = config.enableExtensions;
const listen = config.listen;

const axios = require('axios');
const tiktoken = require('@dqbd/tiktoken');
const WebSocket = require('ws');

var Client = require('node-rest-client').Client;
var client = new Client();

client.on('error', (err) => {
    console.error('An error occurred:', err);
});

let poe = require('./poe-client');

var api_server = "http://0.0.0.0:5000";
var api_novelai = "https://api.novelai.net";
let api_openai = "https://api.openai.com/v1";
var main_api = "kobold";

var response_get_story;
var response_generate;
var response_generate_novel;
var request_promt;
var response_promt;
var characters = {};
var character_i = 0;
var response_create;
var response_edit;
var response_dw_bg;
var response_getstatus;
var response_getstatus_novel;
var response_getlastversion;
var api_key_novel;

let response_generate_openai;
let response_getstatus_openai;
let api_key_openai;

//RossAscends: Added function to format dates used in files and chat timestamps to a humanized format.
//Mostly I wanted this to be for file names, but couldn't figure out exactly where the filename save code was as everything seemed to be connected. 
//During testing, this performs the same as previous date.now() structure.
//It also does not break old characters/chats, as the code just uses whatever timestamp exists in the chat.
//New chats made with characters will use this new formatting.
//Useable variable is (( humanizedISO8601Datetime ))

const delay = ms => new Promise(resolve => setTimeout(resolve, ms))

const { SentencePieceProcessor, cleanText } = require("./src/sentencepiece/sentencepiece.min.js");
let spp = new SentencePieceProcessor();

async function countTokensLlama(text) {
    let cleaned = cleanText(text);

    let ids = spp.encodeIds(cleaned);
    return ids.length;
}

function humanizedISO8601DateTime() {
    let baseDate = new Date(Date.now());
    let humanYear = baseDate.getFullYear();
    let humanMonth = (baseDate.getMonth() + 1);
    let humanDate = baseDate.getDate();
    let humanHour = (baseDate.getHours() < 10 ? '0' : '') + baseDate.getHours();
    let humanMinute = (baseDate.getMinutes() < 10 ? '0' : '') + baseDate.getMinutes();
    let humanSecond = (baseDate.getSeconds() < 10 ? '0' : '') + baseDate.getSeconds();
    let humanMillisecond = (baseDate.getMilliseconds() < 10 ? '0' : '') + baseDate.getMilliseconds();
    let HumanizedDateTime = (humanYear + "-" + humanMonth + "-" + humanDate + " @" + humanHour + "h " + humanMinute + "m " + humanSecond + "s " + humanMillisecond + "ms");
    return HumanizedDateTime;
};

var is_colab = process.env.colaburl !== undefined;
var charactersPath = 'public/characters/';
var chatsPath = 'public/chats/';
const jsonParser = express.json({ limit: '100mb' });
const urlencodedParser = express.urlencoded({ extended: true, limit: '100mb' });
const baseRequestArgs = { headers: { "Content-Type": "application/json" } };
const directories = {
    worlds: 'public/worlds/',
    avatars: 'public/User Avatars',
    groups: 'public/groups/',
    groupChats: 'public/group chats',
    chats: 'public/chats/',
    characters: 'public/characters/',
    backgrounds: 'public/backgrounds',
    novelAI_Settings: 'public/NovelAI Settings',
    koboldAI_Settings: 'public/KoboldAI Settings',
    openAI_Settings: 'public/OpenAI Settings',
    textGen_Settings: 'public/TextGen Settings',
    thumbnails: 'thumbnails/',
    thumbnailsBg: 'thumbnails/bg/',
    thumbnailsAvatar: 'thumbnails/avatar/',
    themes: 'public/themes',
    extensions: 'public/scripts/extensions'
};

// CSRF Protection //
const doubleCsrf = require('csrf-csrf').doubleCsrf;

const CSRF_SECRET = crypto.randomBytes(8).toString('hex');
const COOKIES_SECRET = crypto.randomBytes(8).toString('hex');

const { invalidCsrfTokenError, generateToken, doubleCsrfProtection } = doubleCsrf({
    getSecret: () => CSRF_SECRET,
    cookieName: "X-CSRF-Token",
    cookieOptions: {
        httpOnly: true,
        sameSite: "strict",
        secure: false
    },
    size: 64,
    getTokenFromRequest: (req) => req.headers["x-csrf-token"]
});



app.get("/csrf-token", (req, res) => {
    res.json({
        "token": generateToken(res)
    });
});

app.use(cookieParser(COOKIES_SECRET));
app.use(doubleCsrfProtection);

// CORS Settings //
const cors = require('cors');
const CORS = cors({
    origin: 'null',
    methods: ['OPTIONS']
});

app.use(CORS);

if (listen && config.basicAuthMode) app.use(basicAuthMiddleware);

app.use(function (req, res, next) { //Security
    let clientIp = req.connection.remoteAddress;
    let ip = ipaddr.parse(clientIp);
    // Check if the IP address is IPv4-mapped IPv6 address
    if (ip.kind() === 'ipv6' && ip.isIPv4MappedAddress()) {
        const ipv4 = ip.toIPv4Address().toString();
        clientIp = ipv4;
    } else {
        clientIp = ip;
        clientIp = clientIp.toString();
    }

    //clientIp = req.connection.remoteAddress.split(':').pop();
    if (whitelistMode === true && !whitelist.includes(clientIp)) {
        console.log('Forbidden: Connection attempt from ' + clientIp + '. If you are attempting to connect, please add your IP address in whitelist or disable whitelist mode in config.conf in root of SillyTavern folder.\n');
        return res.status(403).send('<b>Forbidden</b>: Connection attempt from <b>' + clientIp + '</b>. If you are attempting to connect, please add your IP address in whitelist or disable whitelist mode in config.conf in root of SillyTavern folder.');
    }
    next();
});

app.use((req, res, next) => {
    if (req.url.startsWith('/characters/') && is_colab && process.env.googledrive == 2) {

        const filePath = path.join(charactersPath, decodeURIComponent(req.url.substr('/characters'.length)));
        console.log('req.url: ' + req.url);
        console.log(filePath);
        fs.access(filePath, fs.constants.R_OK, (err) => {
            if (!err) {
                res.sendFile(filePath, { root: __dirname });
            } else {
                res.send('Character not found: ' + filePath);
                //next();
            }
        });
    } else {
        next();
    }
});

app.use(express.static(__dirname + "/public", { refresh: true }));

app.use('/backgrounds', (req, res) => {
    const filePath = decodeURIComponent(path.join(__dirname, 'public/backgrounds', req.url.replace(/%20/g, ' ')));
    fs.readFile(filePath, (err, data) => {
        if (err) {
            res.status(404).send('File not found');
            return;
        }
        //res.contentType('image/jpeg');
        res.send(data);
    });
});

app.use('/characters', (req, res) => {
    const filePath = decodeURIComponent(path.join(__dirname, charactersPath, req.url.replace(/%20/g, ' ')));
    fs.readFile(filePath, (err, data) => {
        if (err) {
            res.status(404).send('File not found');
            return;
        }
        res.send(data);
    });
});
app.use(multer({ dest: "uploads" }).single("avatar"));
app.get("/", function (request, response) {
    response.sendFile(__dirname + "/public/index.html");
});
app.get("/notes/*", function (request, response) {
    response.sendFile(__dirname + "/public" + request.url + ".html");
});
app.get('/get_faq', function (_, response) {
    response.sendFile(__dirname + "/faq.md");
});
app.get('/get_readme', function (_, response) {
    response.sendFile(__dirname + "/readme.md");
});

//**************Kobold api
app.post("/generate", jsonParser, async function (request, response_generate = response) {
    if (!request.body) return response_generate.sendStatus(400);
    //console.log(request.body.prompt);
    //const dataJson = JSON.parse(request.body);
    request_promt = request.body.prompt;

    //console.log(request.body);
    var this_settings = {
        prompt: request_promt,
        use_story: false,
        use_memory: false,
        use_authors_note: false,
        use_world_info: false,
        max_context_length: request.body.max_context_length,
        singleline: !!request.body.singleline,
        //temperature: request.body.temperature,
        //max_length: request.body.max_length
    };

    if (request.body.gui_settings == false) {
        var sampler_order = [request.body.s1, request.body.s2, request.body.s3, request.body.s4, request.body.s5, request.body.s6, request.body.s7];
        this_settings = {
            prompt: request_promt,
            use_story: false,
            use_memory: false,
            use_authors_note: false,
            use_world_info: false,
            max_context_length: request.body.max_context_length,
            max_length: request.body.max_length,
            rep_pen: request.body.rep_pen,
            rep_pen_range: request.body.rep_pen_range,
            rep_pen_slope: request.body.rep_pen_slope,
            temperature: request.body.temperature,
            tfs: request.body.tfs,
            top_a: request.body.top_a,
            top_k: request.body.top_k,
            top_p: request.body.top_p,
            typical: request.body.typical,
            sampler_order: sampler_order,
            singleline: !!request.body.singleline,
        };
        if (!!request.body.stop_sequence) {
            this_settings['stop_sequence'] = request.body.stop_sequence;
        }
    }

    console.log(this_settings);
    var args = {
        data: this_settings,
        headers: { "Content-Type": "application/json" }
    };

    const MAX_RETRIES = 10;
    const delayAmount = 3000;
    for (let i = 0; i < MAX_RETRIES; i++) {
        try {
            const data = await postAsync(api_server + "/v1/generate", args);
            console.log(data);
            return response_generate.send(data);
        }
        catch (error) {
            // data
            console.log(error[0]);

            // response
            if (error[1]) {
                switch (error[1].statusCode) {
                    case 503:
                        await delay(delayAmount);
                        break;
                    default:
                        return response_generate.send({ error: true });
                }
            } else {
                return response_generate.send({ error: true });
            }
        }
    }
});

//************** Text generation web UI
app.post("/generate_textgenerationwebui", jsonParser, async function (request, response_generate = response) {
    if (!request.body) return response_generate.sendStatus(400);

    console.log(request.body);

    if (!!request.header('X-Response-Streaming')) {
        let isStreamingStopped = false;
        request.socket.on('close', function () {
            isStreamingStopped = true;
        });

        response_generate.writeHead(200, {
            'Content-Type': 'text/plain;charset=utf-8',
            'Transfer-Encoding': 'chunked',
            'Cache-Control': 'no-transform',
        });

        async function* readWebsocket() {
            const streamingUrl = request.header('X-Streaming-URL');
            const websocket = new WebSocket(streamingUrl);

            websocket.on('open', async function () {
                console.log('websocket open');
                websocket.send(JSON.stringify(request.body));
            });

            websocket.on('error', (err) => {
                console.error(err);
                websocket.close();
            });

            websocket.on('close', (code, buffer) => {
                const reason = new TextDecoder().decode(buffer)
                console.log(reason);
            });

            while (true) {
                if (isStreamingStopped) {
                    console.error('Streaming stopped by user. Closing websocket...');
                    websocket.close();
                    return;
                }

                const rawMessage = await new Promise(resolve => websocket.once('message', resolve));
                const message = json5.parse(rawMessage);

                switch (message.event) {
                    case 'text_stream':
                        yield message.text;
                        break;
                    case 'stream_end':
                        websocket.close();
                        return;
                }
            }
        }

        let reply = '';

        try {
            for await (const text of readWebsocket()) {
                if (typeof text !== 'string') {
                    break;
                }

                let newText = text;

                if (!newText) {
                    continue;
                }

                reply += text;
                response_generate.write(newText);
            }

            console.log(reply);
        }
        finally {
            response_generate.end();
        }
    }
    else {
        var args = {
            data: request.body,
            headers: { "Content-Type": "application/json" }
        };
        client.post(api_server + "/v1/generate", args, function (data, response) {
            console.log("####", data);
            if (response.statusCode == 200) {
                console.log(data);
                response_generate.send(data);
            }
            if (response.statusCode == 422) {
                console.log('Validation error');
                response_generate.send({ error: true });
            }
            if (response.statusCode == 501 || response.statusCode == 503 || response.statusCode == 507) {
                console.log(data);
                response_generate.send({ error: true });
            }
        }).on('error', function (err) {
            console.log(err);
            //console.log('something went wrong on the request', err.request.options);
            response_generate.send({ error: true });
        });
    }
});


app.post("/savechat", jsonParser, function (request, response) {
    var dir_name = String(request.body.avatar_url).replace('.png', '');
    let chat_data = request.body.chat;
    let jsonlData = chat_data.map(JSON.stringify).join('\n');
    fs.writeFile(chatsPath + dir_name + "/" + request.body.file_name + '.jsonl', jsonlData, 'utf8', function (err) {
        if (err) {
            response.send(err);
            return console.log(err);
        } else {
            response.send({ result: "ok" });
        }
    });

});
app.post("/getchat", jsonParser, function (request, response) {
    var dir_name = String(request.body.avatar_url).replace('.png', '');

    fs.stat(chatsPath + dir_name, function (err, stat) {

        if (stat === undefined) {		//if no chat dir for the character is found, make one with the character name

            fs.mkdirSync(chatsPath + dir_name);
            response.send({});
            return;
        } else {

            if (err === null) { //if there is a dir, then read the requested file from the JSON call

                fs.stat(chatsPath + dir_name + "/" + request.body.file_name + ".jsonl", function (err, stat) {

                    if (err === null) { //if no error (the file exists), read the file
                        if (stat !== undefined) {
                            fs.readFile(chatsPath + dir_name + "/" + request.body.file_name + ".jsonl", 'utf8', (err, data) => {
                                if (err) {
                                    console.error(err);
                                    response.send(err);
                                    return;
                                }
                                //console.log(data);
                                const lines = data.split('\n');

                                // Iterate through the array of strings and parse each line as JSON
                                const jsonData = lines.map(json5.parse);
                                response.send(jsonData);
                                //console.log('read the requested file')

                            });
                        }
                    } else {
                        response.send({});
                        //return console.log(err);
                        return;
                    }
                });
            } else {
                console.error(err);
                response.send({});
                return;
            }
        }
    });


});
app.post("/getstatus", jsonParser, async function (request, response_getstatus = response) {
    if (!request.body) return response_getstatus.sendStatus(400);
    api_server = request.body.api_server;
    main_api = request.body.main_api;
    if (api_server.indexOf('localhost') != -1) {
        api_server = api_server.replace('localhost', '127.0.0.1');
    }
    var args = {
        headers: { "Content-Type": "application/json" }
    };
    var url = api_server + "/v1/model";
    let version = '';
    if (main_api == "kobold") {
        try {
            version = (await getAsync(api_server + "/v1/info/version")).result;
        }
        catch {
            version = '0.0.0';
        }
    }
    client.get(url, args, function (data, response) {
        if (response.statusCode == 200) {
            data.version = version;
            if (data.result != "ReadOnly") {
            } else {
                data.result = "no_connection";
            }
        } else {
            data.result = "no_connection";
        }
        response_getstatus.send(data);
    }).on('error', function (err) {
        response_getstatus.send({ result: "no_connection" });
    });
});

const formatApiUrl = (url) => (url.indexOf('localhost') !== -1)
    ? url.replace('localhost', '127.0.0.1')
    : url;

app.post('/getsoftprompts', jsonParser, async function (request, response) {
    if (!request.body || !request.body.api_server) {
        return response.sendStatus(400);
    }

    const baseUrl = formatApiUrl(request.body.api_server);
    let soft_prompts = [];

    try {
        const softPromptsList = (await getAsync(`${baseUrl}/v1/config/soft_prompts_list`, baseRequestArgs)).values.map(x => x.value);
        const softPromptSelected = (await getAsync(`${baseUrl}/v1/config/soft_prompt`, baseRequestArgs)).value;
        soft_prompts = softPromptsList.map(x => ({ name: x, selected: x === softPromptSelected }));
    } catch (err) {
        soft_prompts = [];
    }

    return response.send({ soft_prompts });
});

app.post("/setsoftprompt", jsonParser, async function (request, response) {
    if (!request.body || !request.body.api_server) {
        return response.sendStatus(400);
    }

    const baseUrl = formatApiUrl(request.body.api_server);
    const args = {
        headers: { "Content-Type": "application/json" },
        data: { value: request.body.name ?? '' },
    };

    try {
        await putAsync(`${baseUrl}/v1/config/soft_prompt`, args);
    } catch {
        return response.sendStatus(500);
    }

    return response.sendStatus(200);
});

function checkServer() {
    api_server = 'http://127.0.0.1:5000';
    var args = {
        headers: { "Content-Type": "application/json" }
    };
    client.get(api_server + "/v1/model", args, function (data, response) {
        console.log(data.result);
        console.log(data);
    }).on('error', function (err) {
        console.log(err);
    });
}

//***************** Main functions
function charaFormatData(data) {
    var char = { "name": data.ch_name, "description": data.description, "personality": data.personality, "first_mes": data.first_mes, "avatar": 'none', "chat": data.ch_name + ' - ' + humanizedISO8601DateTime(), "mes_example": data.mes_example, "scenario": data.scenario, "create_date": humanizedISO8601DateTime(), "talkativeness": data.talkativeness, "fav": data.fav };
    return char;
}

app.post("/createcharacter", urlencodedParser, function (request, response) {
    if (!request.body) return response.sendStatus(400);

    request.body.ch_name = sanitize(request.body.ch_name);

    const char = JSON.stringify(charaFormatData(request.body));
    const internalName = getPngName(request.body.ch_name);
    const avatarName = `${internalName}.png`;
    const defaultAvatar = './public/img/ai4.png';
    const chatsPath = directories.chats + internalName; //path.join(chatsPath, internalName);

    if (!fs.existsSync(chatsPath)) fs.mkdirSync(chatsPath);

    if (!request.file) {
        charaWrite(defaultAvatar, char, internalName, response, avatarName);
    } else {
        const uploadPath = path.join("./uploads/", request.file.filename);
        charaWrite(uploadPath, char, internalName, response, avatarName);
    }
});

app.post("/renamecharacter", jsonParser, async function (request, response) {
    if (!request.body.avatar_url || !request.body.new_name) {
        return response.sendStatus(400);
    }

    const oldAvatarName = request.body.avatar_url;
    const newName = sanitize(request.body.new_name);
    const oldInternalName = path.parse(request.body.avatar_url).name;
    const newInternalName = getPngName(newName);
    const newAvatarName = `${newInternalName}.png`;

    const oldAvatarPath = path.join(charactersPath, oldAvatarName);
    const newAvatarPath = path.join(charactersPath, newAvatarName);

    const oldChatsPath = path.join(chatsPath, oldInternalName);
    const newChatsPath = path.join(chatsPath, newInternalName);

    try {
        // Read old file, replace name int it
        const rawOldData = await charaRead(oldAvatarPath);
        const oldData = json5.parse(rawOldData);
        oldData['name'] = newName;
        const newData = JSON.stringify(oldData);

        // Write data to new location
        await charaWrite(oldAvatarPath, newData, newInternalName);

        // Rename chats folder
        if (fs.existsSync(oldChatsPath) && !fs.existsSync(newChatsPath)) {
            fs.renameSync(oldChatsPath, newChatsPath);
        }

        // Remove the old character file
        fs.rmSync(oldAvatarPath);

        // Return new avatar name to ST
        return response.send({ 'avatar': newAvatarName });
    }
    catch (err) {
        console.error(err);
        return response.sendStatus(500);
    }
});

app.post("/editcharacter", urlencodedParser, async function (request, response) {
    if (!request.body) {
        console.error('Error: no response body detected');
        response.status(400).send('Error: no response body detected');
        return;
    }

    if (request.body.ch_name === '' || request.body.ch_name === undefined || request.body.ch_name === '.') {
        console.error('Error: invalid name.');
        response.status(400).send('Error: invalid name.');
        return;
    }

    let char = charaFormatData(request.body);
    char.chat = request.body.chat;
    char.create_date = request.body.create_date;
    char = JSON.stringify(char);
    let target_img = (request.body.avatar_url).replace('.png', '');

    try {
        if (!request.file) {
            const avatarPath = path.join(charactersPath, request.body.avatar_url);
            await charaWrite(avatarPath, char, target_img, response, 'Character saved');
        } else {
            const newAvatarPath = path.join("./uploads/", request.file.filename);
            invalidateThumbnail('avatar', request.body.avatar_url);
            await charaWrite(newAvatarPath, char, target_img, response, 'Character saved');
        }
    }
    catch {
        console.error('An error occured, character edit invalidated.');
    }
});

app.post("/deletecharacter", urlencodedParser, function (request, response) {
    if (!request.body || !request.body.avatar_url) {
        return response.sendStatus(400);
    }

    if (request.body.avatar_url !== sanitize(request.body.avatar_url)) {
        console.error('Malicious filename prevented');
        return response.sendStatus(403);
    }

    const avatarPath = charactersPath + request.body.avatar_url;
    if (!fs.existsSync(avatarPath)) {
        return response.sendStatus(400);
    }

    fs.rmSync(avatarPath);
    invalidateThumbnail('avatar', request.body.avatar_url);
    let dir_name = (request.body.avatar_url.replace('.png', ''));

    if (!dir_name.length) {
        console.error('Malicious dirname prevented');
        return response.sendStatus(403);
    }

    rimraf(path.join(chatsPath, sanitize(dir_name)), (err) => {
        if (err) {
            response.send(err);
            return console.log(err);
        } else {
            //response.redirect("/");

            response.send('ok');
        }
    });
});

async function charaWrite(img_url, data, target_img, response = undefined, mes = 'ok') {
    try {
        // Read the image, resize, and save it as a PNG into the buffer
        const rawImg = await jimp.read(img_url);
        const image = await rawImg.cover(400, 600).getBufferAsync(jimp.MIME_PNG);

        // Get the chunks
        const chunks = extract(image);
        const tEXtChunks = chunks.filter(chunk => chunk.create_date === 'tEXt');

        // Remove all existing tEXt chunks
        for (let tEXtChunk of tEXtChunks) {
            chunks.splice(chunks.indexOf(tEXtChunk), 1);
        }
        // Add new chunks before the IEND chunk
        const base64EncodedData = Buffer.from(data, 'utf8').toString('base64');
        chunks.splice(-1, 0, PNGtext.encode('chara', base64EncodedData));
        //chunks.splice(-1, 0, text.encode('lorem', 'ipsum'));

        fs.writeFileSync(charactersPath + target_img + '.png', new Buffer.from(encode(chunks)));
        if (response !== undefined) response.send(mes);


    } catch (err) {
        console.log(err);
        if (response !== undefined) response.send(err);
    }
}

async function charaRead(img_url, input_format) {
    let format;
    if (input_format === undefined) {
        if (img_url.indexOf('.webp') !== -1) {
            format = 'webp';
        } else {
            format = 'png';
        }
    } else {
        format = input_format;
    }

    switch (format) {
        case 'webp':
            const exif_data = await ExifReader.load(fs.readFileSync(img_url));
            const char_data = exif_data['UserComment']['description'];
            if (char_data === 'Undefined' && exif_data['UserComment'].value && exif_data['UserComment'].value.length === 1) {
                return exif_data['UserComment'].value[0];
            }
            return char_data;
        case 'png':
            const buffer = fs.readFileSync(img_url);
            const chunks = extract(buffer);

            const textChunks = chunks.filter(function (chunk) {
                return chunk.name === 'tEXt';
            }).map(function (chunk) {
                return PNGtext.decode(chunk.data);
            });
            var base64DecodedData = Buffer.from(textChunks[0].text, 'base64').toString('utf8');
            return base64DecodedData;//textChunks[0].text;
        default:
            break;
    }
}

app.post("/getcharacters", jsonParser, function (request, response) {
    fs.readdir(charactersPath, async (err, files) => {
        if (err) {
            console.error(err);
            return;
        }

        const pngFiles = files.filter(file => file.endsWith('.png'));

        //console.log(pngFiles);
        characters = {};
        var i = 0;
        for (const item of pngFiles) {
            try {
                var img_data = await charaRead(charactersPath + item);
                let jsonObject = json5.parse(img_data);
                jsonObject.avatar = item;
                //console.log(jsonObject);
                characters[i] = {};
                characters[i] = jsonObject;

                try {
                    const charStat = fs.statSync(path.join(charactersPath, item));
                    characters[i]['date_added'] = charStat.birthtimeMs;
                    const char_dir = path.join(chatsPath, item.replace('.png', ''));

                    let chat_size = 0;
                    let date_last_chat = 0;

                    if (fs.existsSync(char_dir)) {
                        const chats = fs.readdirSync(char_dir);

                        if (Array.isArray(chats) && chats.length) {
                            for (const chat of chats) {
                                const chatStat = fs.statSync(path.join(char_dir, chat));
                                chat_size += chatStat.size;
                                date_last_chat = Math.max(date_last_chat, chatStat.mtimeMs);
                            }
                        }
                    }

                    characters[i]['date_last_chat'] = date_last_chat;
                    characters[i]['chat_size'] = chat_size;
                }
                catch {
                    characters[i]['date_added'] = 0;
                    characters[i]['date_last_chat'] = 0;
                    characters[i]['chat_size'] = 0;
                }

                i++;
            } catch (error) {
                console.log(`Could not read character: ${item}`);
                if (error instanceof SyntaxError) {
                    console.log("String [" + (i) + "] is not valid JSON!");
                } else {
                    console.log("An unexpected error occurred: ", error);
                }
            }
        };
        //console.log(characters);
        response.send(JSON.stringify(characters));
    });

});
app.post("/getbackgrounds", jsonParser, function (request, response) {
    var images = getImages("public/backgrounds");
    response.send(JSON.stringify(images));

});
app.post("/iscolab", jsonParser, function (request, response) {
    let send_data = false;
    if (is_colab) {
        send_data = String(process.env.colaburl).trim();
    }
    response.send({ colaburl: send_data });

});
app.post("/getuseravatars", jsonParser, function (request, response) {
    var images = getImages("public/User Avatars");
    response.send(JSON.stringify(images));

});
app.post("/setbackground", jsonParser, function (request, response) {
    var bg = "#bg1 {background-image: url('../backgrounds/" + request.body.bg + "');}";
    fs.writeFile('public/css/bg_load.css', bg, 'utf8', function (err) {
        if (err) {
            response.send(err);
            return console.log(err);
        } else {
            //response.redirect("/");
            response.send({ result: 'ok' });
        }
    });

});
app.post("/delbackground", jsonParser, function (request, response) {
    if (!request.body) return response.sendStatus(400);

    if (request.body.bg !== sanitize(request.body.bg)) {
        console.error('Malicious bg name prevented');
        return response.sendStatus(403);
    }

    const fileName = path.join('public/backgrounds/', sanitize(request.body.bg));

    if (!fs.existsSync(fileName)) {
        console.log('BG file not found');
        return response.sendStatus(400);
    }

    fs.rmSync(fileName);
    invalidateThumbnail('bg', request.body.bg);
    return response.send('ok');
});

app.post("/delchat", jsonParser, function (request, response) {
    console.log('/delchat entered');
    if (!request.body) {
        console.log('no request body seen');
        return response.sendStatus(400);
    }

    if (request.body.chatfile !== sanitize(request.body.chatfile)) {
        console.error('Malicious chat name prevented');
        return response.sendStatus(403);
    }

    const fileName = path.join(directories.chats, '/', sanitize(request.body.id), '/', sanitize(request.body.chatfile));
    if (!fs.existsSync(fileName)) {
        console.log('Chat file not found');
        return response.sendStatus(400);
    } else {
        console.log('found the chat file: ' + fileName);
        /* fs.unlinkSync(fileName); */
        fs.rmSync(fileName);
        console.log('deleted chat file: ' + fileName);

    }


    return response.send('ok');
});


app.post("/downloadbackground", urlencodedParser, function (request, response) {
    response_dw_bg = response;
    if (!request.body) return response.sendStatus(400);

    let filedata = request.file;
    //console.log(filedata.mimetype);
    var fileType = ".png";
    var img_file = "ai";
    var img_path = "public/img/";

    img_path = "uploads/";
    img_file = filedata.filename;
    if (filedata.mimetype == "image/jpeg") fileType = ".jpeg";
    if (filedata.mimetype == "image/png") fileType = ".png";
    if (filedata.mimetype == "image/gif") fileType = ".gif";
    if (filedata.mimetype == "image/bmp") fileType = ".bmp";
    fs.copyFile(img_path + img_file, 'public/backgrounds/' + img_file + fileType, (err) => {
        invalidateThumbnail('bg', img_file + fileType);
        if (err) {

            return console.log(err);
        } else {
            //console.log(img_file+fileType);
            response_dw_bg.send(img_file + fileType);
        }
        //console.log('The image was copied from temp directory.');
    });


});

app.post("/savesettings", jsonParser, function (request, response) {
    fs.writeFile('public/settings.json', JSON.stringify(request.body), 'utf8', function (err) {
        if (err) {
            response.send(err);
            return console.log(err);
            //response.send(err);
        } else {
            //response.redirect("/");
            response.send({ result: "ok" });
        }
    });
});

app.post('/getsettings', jsonParser, (request, response) => { //Wintermute's code
    const koboldai_settings = [];
    const koboldai_setting_names = [];
    const novelai_settings = [];
    const novelai_setting_names = [];
    const openai_settings = [];
    const openai_setting_names = [];
    const textgenerationwebui_presets = [];
    const textgenerationwebui_preset_names = [];
    const themes = [];
    const settings = fs.readFileSync('public/settings.json', 'utf8', (err, data) => {
        if (err) return response.sendStatus(500);

        return data;
    });
    //Kobold
    const files = fs
        .readdirSync('public/KoboldAI Settings')
        .sort(
            (a, b) =>
                new Date(fs.statSync(`public/KoboldAI Settings/${b}`).mtime) -
                new Date(fs.statSync(`public/KoboldAI Settings/${a}`).mtime)
        );

    const worldFiles = fs
        .readdirSync(directories.worlds)
        .filter(file => path.extname(file).toLowerCase() === '.json')
        .sort((a, b) => a < b);
    const world_names = worldFiles.map(item => path.parse(item).name);

    files.forEach(item => {
        const file = fs.readFileSync(
            `public/KoboldAI Settings/${item}`,
            'utf8',
            (err, data) => {
                if (err) return response.sendStatus(500)

                return data;
            }
        );
        koboldai_settings.push(file);
        koboldai_setting_names.push(item.replace(/\.[^/.]+$/, ''));
    });

    //Novel
    const files2 = fs
        .readdirSync('public/NovelAI Settings')
        .sort(
            (a, b) =>
                new Date(fs.statSync(`public/NovelAI Settings/${b}`).mtime) -
                new Date(fs.statSync(`public/NovelAI Settings/${a}`).mtime)
        );

    files2.forEach(item => {
        const file2 = fs.readFileSync(
            `public/NovelAI Settings/${item}`,
            'utf8',
            (err, data) => {
                if (err) return response.sendStatus(500);

                return data;
            }
        );

        novelai_settings.push(file2);
        novelai_setting_names.push(item.replace(/\.[^/.]+$/, ''));
    });

    //OpenAI
    const files3 = fs
        .readdirSync('public/OpenAI Settings')
        .sort(
            (a, b) =>
                new Date(fs.statSync(`public/OpenAI Settings/${b}`).mtime) -
                new Date(fs.statSync(`public/OpenAI Settings/${a}`).mtime)
        );

    files3.forEach(item => {
        const file3 = fs.readFileSync(
            `public/OpenAI Settings/${item}`,
            'utf8',
            (err, data) => {
                if (err) return response.sendStatus(500);

                return data;
            }
        );

        openai_settings.push(file3);
        openai_setting_names.push(item.replace(/\.[^/.]+$/, ''));
    });

    // TextGenerationWebUI
    const textGenFiles = fs
        .readdirSync(directories.textGen_Settings)
        .sort();

    textGenFiles.forEach(item => {
        const file = fs.readFileSync(
            path.join(directories.textGen_Settings, item),
            'utf8',
            (err, data) => {
                if (err) return response.sendStatus(500);

                return data;
            }
        );

        textgenerationwebui_presets.push(file);
        textgenerationwebui_preset_names.push(item.replace(/\.[^/.]+$/, ''));
    });

    // Theme files
    const themeFiles = fs
        .readdirSync(directories.themes)
        .filter(x => path.parse(x).ext == '.json')
        .sort();

    themeFiles.forEach(item => {
        const file = fs.readFileSync(
            path.join(directories.themes, item),
            'utf-8',
            (err, data) => {
                if (err) return response.sendStatus(500);
                return data;
            }
        );

        try {
            themes.push(json5.parse(file));
        }
        catch {
            // skip
        }
    })

    response.send({
        settings,
        koboldai_settings,
        koboldai_setting_names,
        world_names,
        novelai_settings,
        novelai_setting_names,
        openai_settings,
        openai_setting_names,
        textgenerationwebui_presets,
        textgenerationwebui_preset_names,
        themes,
        enable_extensions: enableExtensions,
    });
});

app.post('/getworldinfo', jsonParser, (request, response) => {
    if (!request.body?.name) {
        return response.sendStatus(400);
    }

    const file = readWorldInfoFile(request.body.name);

    return response.send(file);
});

app.post('/deleteworldinfo', jsonParser, (request, response) => {
    if (!request.body?.name) {
        return response.sendStatus(400);
    }

    const worldInfoName = request.body.name;
    const filename = sanitize(`${worldInfoName}.json`);
    const pathToWorldInfo = path.join(directories.worlds, filename);

    if (!fs.existsSync(pathToWorldInfo)) {
        throw new Error(`World info file ${filename} doesn't exist.`);
    }

    fs.rmSync(pathToWorldInfo);

    return response.sendStatus(200);
});

app.post('/savetheme', jsonParser, (request, response) => {
    if (!request.body || !request.body.name) {
        return response.sendStatus(400);
    }

    const filename = path.join(directories.themes, sanitize(request.body.name) + '.json');
    fs.writeFileSync(filename, JSON.stringify(request.body), 'utf8');

    return response.sendStatus(200);
});

function readWorldInfoFile(worldInfoName) {
    if (!worldInfoName) {
        return { entries: {} };
    }

    const filename = `${worldInfoName}.json`;
    const pathToWorldInfo = path.join(directories.worlds, filename);

    if (!fs.existsSync(pathToWorldInfo)) {
        throw new Error(`World info file ${filename} doesn't exist.`);
    }

    const worldInfoText = fs.readFileSync(pathToWorldInfo, 'utf8');
    const worldInfo = json5.parse(worldInfoText);
    return worldInfo;
}


function getImages(path) {
    return fs
        .readdirSync(path)
        .filter(file => {
            const type = mime.lookup(file);
            return type && type.startsWith('image/');
        })
        .sort(Intl.Collator().compare);
}

//***********Novel.ai API 

app.post("/getstatus_novelai", jsonParser, function (request, response_getstatus_novel = response) {

    if (!request.body) return response_getstatus_novel.sendStatus(400);
    api_key_novel = request.body.key;
    var data = {};
    var args = {
        data: data,

        headers: { "Content-Type": "application/json", "Authorization": "Bearer " + api_key_novel }
    };
    client.get(api_novelai + "/user/subscription", args, function (data, response) {
        if (response.statusCode == 200) {
            //console.log(data);
            response_getstatus_novel.send(data);//data);
        }
        if (response.statusCode == 401) {
            console.log('Access Token is incorrect.');
            response_getstatus_novel.send({ error: true });
        }
        if (response.statusCode == 500 || response.statusCode == 501 || response.statusCode == 501 || response.statusCode == 503 || response.statusCode == 507) {
            console.log(data);
            response_getstatus_novel.send({ error: true });
        }
    }).on('error', function (err) {
        //console.log('');
        //console.log('something went wrong on the request', err.request.options);
        response_getstatus_novel.send({ error: true });
    });
});

app.post("/generate_novelai", jsonParser, function (request, response_generate_novel = response) {
    if (!request.body) return response_generate_novel.sendStatus(400);

    console.log(request.body);
    var data = {
        "input": request.body.input,
        "model": request.body.model,
        "parameters": {
            "use_string": request.body.use_string,
            "temperature": request.body.temperature,
            "max_length": request.body.max_length,
            "min_length": request.body.min_length,
            "tail_free_sampling": request.body.tail_free_sampling,
            "repetition_penalty": request.body.repetition_penalty,
            "repetition_penalty_range": request.body.repetition_penalty_range,
            "repetition_penalty_frequency": request.body.repetition_penalty_frequency,
            "repetition_penalty_presence": request.body.repetition_penalty_presence,
            //"stop_sequences": {{187}},
            //bad_words_ids = {{50256}, {0}, {1}};
            //generate_until_sentence = true;
            "use_cache": request.body.use_cache,
            //use_string = true;
            "return_full_text": request.body.return_full_text,
            "prefix": request.body.prefix,
            "order": request.body.order
        }
    };

    var args = {
        data: data,

        headers: { "Content-Type": "application/json", "Authorization": "Bearer " + api_key_novel }
    };
    client.post(api_novelai + "/ai/generate", args, function (data, response) {
        if (response.statusCode == 201) {
            console.log(data);
            response_generate_novel.send(data);
        }
        if (response.statusCode == 400) {
            console.log('Validation error');
            response_generate_novel.send({ error: true });
        }
        if (response.statusCode == 401) {
            console.log('Access Token is incorrect');
            response_generate_novel.send({ error: true });
        }
        if (response.statusCode == 402) {
            console.log('An active subscription is required to access this endpoint');
            response_generate_novel.send({ error: true });
        }
        if (response.statusCode == 500 || response.statusCode == 409) {
            console.log(data);
            response_generate_novel.send({ error: true });
        }
    }).on('error', function (err) {
        //console.log('');
        //console.log('something went wrong on the request', err.request.options);
        response_getstatus.send({ error: true });
    });
});

app.post("/getallchatsofcharacter", jsonParser, function (request, response) {
    if (!request.body) return response.sendStatus(400);

    var char_dir = (request.body.avatar_url).replace('.png', '')
    fs.readdir(chatsPath + char_dir, (err, files) => {
        if (err) {
            console.log('found error in history loading');
            console.error(err);
            response.send({ error: true });
            return;
        }

        // filter for JSON files
        console.log('looking for JSONL files');
        const jsonFiles = files.filter(file => path.extname(file) === '.jsonl');

        // sort the files by name
        //jsonFiles.sort().reverse();
        // print the sorted file names
        var chatData = {};
        let ii = jsonFiles.length;	//this is the number of files belonging to the character
        if (ii !== 0) {
            //console.log('found '+ii+' chat logs to load');
            for (let i = jsonFiles.length - 1; i >= 0; i--) {
                const file = jsonFiles[i];
                const fileStream = fs.createReadStream(chatsPath + char_dir + '/' + file);
                const rl = readline.createInterface({
                    input: fileStream,
                    crlfDelay: Infinity
                });

                let lastLine;
                rl.on('line', (line) => {
                    lastLine = line;
                });
                rl.on('close', () => {
                    if (lastLine) {
                        let jsonData = json5.parse(lastLine);
                        if (jsonData.name !== undefined) {
                            chatData[i] = {};
                            chatData[i]['file_name'] = file;
                            chatData[i]['mes'] = jsonData['mes'];
                            ii--;
                            if (ii === 0) {
                                console.log('ii count went to zero, responding with chatData');
                                response.send(chatData);
                            }
                        } else {
                            console.log('just returning from getallchatsofcharacter');
                            return;
                        }
                    }
                    console.log('successfully closing getallchatsofcharacter');
                    rl.close();
                });
            };
        } else {
            //console.log('Found No Chats. Exiting Load Routine.');
            response.send({ error: true });
        };
    })
});

function getPngName(file) {
    let i = 1;
    let base_name = file;
    while (fs.existsSync(charactersPath + file + '.png')) {
        file = base_name + i;
        i++;
    }
    return file;
}

app.post("/importcharacter", urlencodedParser, async function (request, response) {

    if (!request.body) return response.sendStatus(400);

    let png_name = '';
    let filedata = request.file;
    let uploadPath = path.join('./uploads', filedata.filename);
    var format = request.body.file_type;
    //console.log(format);
    if (filedata) {
        if (format == 'json') {
            fs.readFile(uploadPath, 'utf8', async (err, data) => {
                if (err) {
                    console.log(err);
                    response.send({ error: true });
                }
                const jsonData = json5.parse(data);

                if (jsonData.name !== undefined) {
                    jsonData.name = sanitize(jsonData.name);

                    png_name = getPngName(jsonData.name);
                    let char = { "name": jsonData.name, "description": jsonData.description ?? '', "personality": jsonData.personality ?? '', "first_mes": jsonData.first_mes ?? '', "avatar": 'none', "chat": jsonData.name + " - " + humanizedISO8601DateTime(), "mes_example": jsonData.mes_example ?? '', "scenario": jsonData.scenario ?? '', "create_date": humanizedISO8601DateTime(), "talkativeness": jsonData.talkativeness ?? 0.5 };
                    char = JSON.stringify(char);
                    charaWrite('./public/img/ai4.png', char, png_name, response, { file_name: png_name });
                } else if (jsonData.char_name !== undefined) {//json Pygmalion notepad
                    jsonData.char_name = sanitize(jsonData.char_name);

                    png_name = getPngName(jsonData.char_name);
                    let char = { "name": jsonData.char_name, "description": jsonData.char_persona ?? '', "personality": '', "first_mes": jsonData.char_greeting ?? '', "avatar": 'none', "chat": jsonData.name + " - " + humanizedISO8601DateTime(), "mes_example": jsonData.example_dialogue ?? '', "scenario": jsonData.world_scenario ?? '', "create_date": humanizedISO8601DateTime(), "talkativeness": jsonData.talkativeness ?? 0.5 };
                    char = JSON.stringify(char);
                    charaWrite('./public/img/ai4.png', char, png_name, response, { file_name: png_name });
                } else {
                    console.log('Incorrect character format .json');
                    response.send({ error: true });
                }
            });
        } else {
            try {
                var img_data = await charaRead(uploadPath, format);
                let jsonData = json5.parse(img_data);
                jsonData.name = sanitize(jsonData.name);

                if (format == 'webp') {
                    let convertedPath = path.join('./uploads', path.basename(uploadPath, ".webp") + ".png")
                    await webp.dwebp(uploadPath, convertedPath, "-o");
                    uploadPath = convertedPath;
                }

                png_name = getPngName(jsonData.name);

                if (jsonData.name !== undefined) {
                    let char = { "name": jsonData.name, "description": jsonData.description ?? '', "personality": jsonData.personality ?? '', "first_mes": jsonData.first_mes ?? '', "avatar": 'none', "chat": jsonData.name + " - " + humanizedISO8601DateTime(), "mes_example": jsonData.mes_example ?? '', "scenario": jsonData.scenario ?? '', "create_date": humanizedISO8601DateTime(), "talkativeness": jsonData.talkativeness ?? 0.5 };
                    char = JSON.stringify(char);
                    await charaWrite(uploadPath, char, png_name, response, { file_name: png_name });
                }
            } catch (err) {
                console.log(err);
                response.send({ error: true });
            }
        }
    }
});

app.post("/exportcharacter", jsonParser, async function (request, response) {
    if (!request.body.format || !request.body.avatar_url) {
        return response.sendStatus(400);
    }

    let filename = path.join(directories.characters, sanitize(request.body.avatar_url));

    if (!fs.existsSync(filename)) {
        return response.sendStatus(404);
    }

    switch (request.body.format) {
        case 'png':
            return response.sendFile(filename, { root: __dirname });
        case 'json': {
            try {
                let json = await charaRead(filename);
                let jsonObject = json5.parse(json);
                return response.type('json').send(jsonObject)
            }
            catch {
                return response.sendStatus(400);
            }
        }
        case 'webp': {
            try {
                let json = await charaRead(filename);
                let inputWebpPath = `./uploads/${Date.now()}_input.webp`;
                let outputWebpPath = `./uploads/${Date.now()}_output.webp`;
                let metadataPath = `./uploads/${Date.now()}_metadata.exif`;
                let metadata =
                {
                    "Exif": {
                        [exif.ExifIFD.UserComment]: json,
                    },
                };
                const exifString = exif.dump(metadata);
                fs.writeFileSync(metadataPath, exifString, 'binary');

                await webp.cwebp(filename, inputWebpPath, '-q 95');
                await webp.webpmux_add(inputWebpPath, outputWebpPath, metadataPath, 'exif');

                response.sendFile(outputWebpPath, { root: __dirname });

                fs.rmSync(inputWebpPath);
                fs.rmSync(metadataPath);

                return;
            }
            catch (err) {
                console.log(err);
                return response.sendStatus(400);
            }
        }
    }

    return response.sendStatus(400);
});


app.post("/importchat", urlencodedParser, function (request, response) {
    if (!request.body) return response.sendStatus(400);

    var format = request.body.file_type;
    let filedata = request.file;
    let avatar_url = (request.body.avatar_url).replace('.png', '');
    let ch_name = request.body.character_name;
    if (filedata) {

        if (format === 'json') {
            fs.readFile('./uploads/' + filedata.filename, 'utf8', (err, data) => {

                if (err) {
                    console.log(err);
                    response.send({ error: true });
                }

                const jsonData = json5.parse(data);
                if (jsonData.histories !== undefined) {
                    //console.log('/importchat confirms JSON histories are defined');
                    const chat = {
                        from(history) {
                            return [
                                {
                                    user_name: 'You',
                                    character_name: ch_name,
                                    create_date: humanizedISO8601DateTime(),

                                },
                                ...history.msgs.map(
                                    (message) => ({
                                        name: message.src.is_human ? 'You' : ch_name,
                                        is_user: message.src.is_human,
                                        is_name: true,
                                        send_date: humanizedISO8601DateTime(),
                                        mes: message.text,
                                    })
                                )];
                        }
                    }

                    const newChats = [];
                    (jsonData.histories.histories ?? []).forEach((history) => {
                        newChats.push(chat.from(history));
                    });

                    const errors = [];
                    newChats.forEach(chat => fs.writeFile(
                        chatsPath + avatar_url + '/' + ch_name + ' - ' + humanizedISO8601DateTime() + ' imported.jsonl',
                        chat.map(JSON.stringify).join('\n'),
                        'utf8',
                        (err) => err ?? errors.push(err)
                    )
                    );

                    if (0 < errors.length) {
                        response.send('Errors occurred while writing character files. Errors: ' + JSON.stringify(errors));
                    }

                    response.send({ res: true });
                } else {
                    response.send({ error: true });
                }
            });
        }
        if (format === 'jsonl') {
            //console.log(humanizedISO8601DateTime()+':imported chat format is JSONL');
            const fileStream = fs.createReadStream('./uploads/' + filedata.filename);
            const rl = readline.createInterface({
                input: fileStream,
                crlfDelay: Infinity
            });

            rl.once('line', (line) => {
                let jsonData = json5.parse(line);

                if (jsonData.user_name !== undefined) {
                    //console.log(humanizedISO8601DateTime()+':/importchat copying chat as '+ch_name+' - '+humanizedISO8601DateTime()+'.jsonl');
                    fs.copyFile('./uploads/' + filedata.filename, chatsPath + avatar_url + '/' + ch_name + ' - ' + humanizedISO8601DateTime() + '.jsonl', (err) => { //added character name and replaced Date.now() with humanizedISO8601DateTime
                        if (err) {
                            response.send({ error: true });
                            return console.log(err);
                        } else {
                            response.send({ res: true });
                            return;
                        }
                    });
                } else {
                    //response.send({error:true});
                    return;
                }
                rl.close();
            });
        }

    }

});

app.post('/importworldinfo', urlencodedParser, (request, response) => {
    if (!request.file) return response.sendStatus(400);

    const filename = sanitize(request.file.originalname);

    if (path.parse(filename).ext.toLowerCase() !== '.json') {
        return response.status(400).send('Only JSON files are supported.')
    }

    const pathToUpload = path.join('./uploads/', request.file.filename);
    const fileContents = fs.readFileSync(pathToUpload, 'utf8');

    try {
        const worldContent = json5.parse(fileContents);
        if (!('entries' in worldContent)) {
            throw new Error('File must contain a world info entries list');
        }
    } catch (err) {
        return response.status(400).send('Is not a valid world info file');
    }

    const pathToNewFile = path.join(directories.worlds, filename);
    const worldName = path.parse(pathToNewFile).name;

    if (!worldName) {
        return response.status(400).send('World file must have a name');
    }

    fs.writeFileSync(pathToNewFile, fileContents);
    return response.send({ name: worldName });
});

app.post('/editworldinfo', jsonParser, (request, response) => {
    if (!request.body) {
        return response.sendStatus(400);
    }

    if (!request.body.name) {
        return response.status(400).send('World file must have a name');
    }

    try {
        if (!('entries' in request.body.data)) {
            throw new Error('World info must contain an entries list');
        }
    } catch (err) {
        return response.status(400).send('Is not a valid world info file');
    }

    const filename = `${request.body.name}.json`;
    const pathToFile = path.join(directories.worlds, filename);

    fs.writeFileSync(pathToFile, JSON.stringify(request.body.data));

    return response.send({ ok: true });
});

app.post('/uploaduseravatar', urlencodedParser, async (request, response) => {
    if (!request.file) return response.sendStatus(400);

    try {
        const pathToUpload = path.join('./uploads/' + request.file.filename);
        const rawImg = await jimp.read(pathToUpload);
        const image = await rawImg.cover(400, 400).getBufferAsync(jimp.MIME_PNG);

        const filename = `${Date.now()}.png`;
        const pathToNewFile = path.join(directories.avatars, filename);
        fs.writeFileSync(pathToNewFile, image);
        fs.rmSync(pathToUpload);
        return response.send({ path: filename });
    } catch (err) {
        return response.status(400).send('Is not a valid image');
    }
});

app.post('/getgroups', jsonParser, (_, response) => {
    const groups = [];

    if (!fs.existsSync(directories.groups)) {
        fs.mkdirSync(directories.groups);
    }

    const files = fs.readdirSync(directories.groups);
    files.forEach(function (file) {
        const fileContents = fs.readFileSync(path.join(directories.groups, file), 'utf8');
        const group = json5.parse(fileContents);
        groups.push(group);
    });

    return response.send(groups);
});

app.post('/creategroup', jsonParser, (request, response) => {
    if (!request.body) {
        return response.sendStatus(400);
    }

    const id = Date.now();
    const chatMetadata = {
        id: id,
        name: request.body.name ?? 'New Group',
        members: request.body.members ?? [],
        avatar_url: request.body.avatar_url,
        allow_self_responses: !!request.body.allow_self_responses,
        activation_strategy: request.body.activation_strategy ?? 0,
        chat_metadata: request.body.chat_metadata ?? {},
        fav: request.body.fav,
    };
    const pathToFile = path.join(directories.groups, `${id}.json`);
    const fileData = JSON.stringify(chatMetadata);

    if (!fs.existsSync(directories.groups)) {
        fs.mkdirSync(directories.groups);
    }

    fs.writeFileSync(pathToFile, fileData);
    return response.send(chatMetadata);
});

app.post('/editgroup', jsonParser, (request, response) => {
    if (!request.body || !request.body.id) {
        return response.sendStatus(400);
    }
    const id = request.body.id;
    const pathToFile = path.join(directories.groups, `${id}.json`);
    const fileData = JSON.stringify(request.body);

    fs.writeFileSync(pathToFile, fileData);
    return response.send({ ok: true });
});

app.post('/getgroupchat', jsonParser, (request, response) => {
    if (!request.body || !request.body.id) {
        return response.sendStatus(400);
    }

    const id = request.body.id;
    const pathToFile = path.join(directories.groupChats, `${id}.jsonl`);

    if (fs.existsSync(pathToFile)) {
        const data = fs.readFileSync(pathToFile, 'utf8');
        const lines = data.split('\n');

        // Iterate through the array of strings and parse each line as JSON
        const jsonData = lines.map(json5.parse);
        return response.send(jsonData);
    } else {
        return response.send([]);
    }
});

app.post('/savegroupchat', jsonParser, (request, response) => {
    if (!request.body || !request.body.id) {
        return response.sendStatus(400);
    }

    const id = request.body.id;
    const pathToFile = path.join(directories.groupChats, `${id}.jsonl`);

    if (!fs.existsSync(directories.groupChats)) {
        fs.mkdirSync(directories.groupChats);
    }

    let chat_data = request.body.chat;
    let jsonlData = chat_data.map(JSON.stringify).join('\n');
    fs.writeFileSync(pathToFile, jsonlData, 'utf8');
    return response.send({ ok: true });
});

app.post('/deletegroup', jsonParser, async (request, response) => {
    if (!request.body || !request.body.id) {
        return response.sendStatus(400);
    }

    const id = request.body.id;
    const pathToGroup = path.join(directories.groups, sanitize(`${id}.json`));
    const pathToChat = path.join(directories.groupChats, sanitize(`${id}.jsonl`));

    if (fs.existsSync(pathToGroup)) {
        fs.rmSync(pathToGroup);
    }

    if (fs.existsSync(pathToChat)) {
        fs.rmSync(pathToChat);
    }

    return response.send({ ok: true });
});

const POE_DEFAULT_BOT = 'a2';

async function getPoeClient(token, useCache = false) {
    let client = new poe.Client(false, useCache);
    await client.init(token);
    return client;
}

app.post('/status_poe', jsonParser, async (request, response) => {
    if (!request.body.token) {
        return response.sendStatus(400);
    }

    try {
        const client = await getPoeClient(request.body.token);
        const botNames = client.get_bot_names();
        client.disconnect_ws();

        return response.send({ 'bot_names': botNames });
    }
    catch {
        return response.sendStatus(401);
    }
});

app.post('/purge_poe', jsonParser, async (request, response) => {
    if (!request.body.token) {
        return response.sendStatus(400);
    }

    const token = request.body.token;
    const bot = request.body.bot ?? POE_DEFAULT_BOT;
    const count = request.body.count ?? -1;

    try {
        const client = await getPoeClient(token, true);
        await client.purge_conversation(bot, count);
        client.disconnect_ws();

        return response.send({ "ok": true });
    }
    catch {
        return response.sendStatus(500);
    }
});

app.post('/generate_poe', jsonParser, async (request, response) => {
    if (!request.body.token || !request.body.prompt) {
        return response.sendStatus(400);
    }

    const token = request.body.token;
    const prompt = request.body.prompt;
    const bot = request.body.bot ?? POE_DEFAULT_BOT;
    const streaming = request.body.streaming ?? false;

    let client;

    try {
        client = await getPoeClient(token, true);
    }
    catch (error) {
        console.error(error);
        return response.sendStatus(500);
    }

    if (streaming) {
        let isStreamingStopped = false;
        request.socket.on('close', function () {
            isStreamingStopped = true;
            client.abortController.abort();
        });

        try {
            response.writeHead(200, {
                'Content-Type': 'text/plain;charset=utf-8',
                'Transfer-Encoding': 'chunked',
                'Cache-Control': 'no-transform',
            });

            let reply = '';
            for await (const mes of client.send_message(bot, prompt)) {
                if (isStreamingStopped) {
                    console.error('Streaming stopped by user. Closing websocket...');
                    break;
                }

                let newText = mes.text.substring(reply.length);
                reply = mes.text;
                response.write(newText);
            }
            console.log(reply);
        }
        catch (err) {
            console.error(err);
        }
        finally {
            client.disconnect_ws();
            return response.end();
        }
    }
    else {
        try {
            let reply;
            for await (const mes of client.send_message(bot, prompt)) {
                reply = mes.text;
            }
            console.log(reply);
            client.disconnect_ws();
            return response.send({ 'reply': reply });
        }
        catch {
            client.disconnect_ws();
            return response.sendStatus(500);
        }
    }
});

app.get('/discover_extensions', jsonParser, function (_, response) {
    const extensions = fs
        .readdirSync(directories.extensions)
        .filter(f => fs.statSync(path.join(directories.extensions, f)).isDirectory());

    return response.send(extensions);
});

app.get('/get_sprites', jsonParser, function (request, response) {
    const name = request.query.name;
    const spritesPath = path.join(directories.characters, name);
    let sprites = [];

    try {
        if (fs.existsSync(spritesPath) && fs.statSync(spritesPath).isDirectory()) {
            sprites = fs.readdirSync(spritesPath)
                .filter(file => {
                    const mimeType = mime.lookup(file);
                    return mimeType && mimeType.startsWith('image/');
                })
                .map((file) => {
                    const pathToSprite = path.join(spritesPath, file);
                    return {
                        label: path.parse(pathToSprite).name.toLowerCase(),
                        path: `/characters/${name}/${file}`,
                    };
                });
        }
    }
    catch (err) {
        console.log(err);
    }
    finally {
        return response.send(sprites);
    }
});

function getThumbnailFolder(type) {
    let thumbnailFolder;

    switch (type) {
        case 'bg':
            thumbnailFolder = directories.thumbnailsBg;
            break;
        case 'avatar':
            thumbnailFolder = directories.thumbnailsAvatar;
            break;
    }

    return thumbnailFolder;
}

function getOriginalFolder(type) {
    let originalFolder;

    switch (type) {
        case 'bg':
            originalFolder = directories.backgrounds;
            break;
        case 'avatar':
            originalFolder = directories.characters;
            break;
    }

    return originalFolder;
}

function invalidateThumbnail(type, file) {
    const folder = getThumbnailFolder(type);
    const pathToThumbnail = path.join(folder, file);

    if (fs.existsSync(pathToThumbnail)) {
        fs.rmSync(pathToThumbnail);
    }
}

async function ensureThumbnailCache() {
    const cacheFiles = fs.readdirSync(directories.thumbnailsBg);

    // files exist, all ok
    if (cacheFiles.length) {
        return;
    }

    console.log('Generating thumbnails cache. Please wait...');

    const bgFiles = fs.readdirSync(directories.backgrounds);
    const tasks = [];

    for (const file of bgFiles) {
        tasks.push(generateThumbnail('bg', file));
    }

    await Promise.all(tasks);
    console.log(`Done! Generated: ${bgFiles.length} preview images`);
}

async function generateThumbnail(type, file) {
    const pathToCachedFile = path.join(getThumbnailFolder(type), file);
    const pathToOriginalFile = path.join(getOriginalFolder(type), file);

    const cachedFileExists = fs.existsSync(pathToCachedFile);
    const originalFileExists = fs.existsSync(pathToOriginalFile);

    // to handle cases when original image was updated after thumb creation
    let shouldRegenerate = false;

    if (cachedFileExists && originalFileExists) {
        const originalStat = fs.statSync(pathToOriginalFile);
        const cachedStat = fs.statSync(pathToCachedFile);

        if (originalStat.mtimeMs > cachedStat.ctimeMs) {
            //console.log('Original file changed. Regenerating thumbnail...');
            shouldRegenerate = true;
        }
    }

    if (cachedFileExists && !shouldRegenerate) {
        return pathToCachedFile;
    }

    if (!originalFileExists) {
        return null;
    }

    const imageSizes = { 'bg': [160, 90], 'avatar': [96, 144] };
    const mySize = imageSizes[type];

    try {
        const image = await jimp.read(pathToOriginalFile);
        const buffer = await image.cover(mySize[0], mySize[1]).quality(95).getBufferAsync(mime.lookup('jpg'));
        fs.writeFileSync(pathToCachedFile, buffer);
    }
    catch (err) {
        return null;
    }

    return pathToCachedFile;
}

app.get('/thumbnail', jsonParser, async function (request, response) {
    const type = request.query.type;
    const file = sanitize(request.query.file);

    if (!type || !file) {
        return response.sendStatus(400);
    }

    if (!(type == 'bg' || type == 'avatar')) {
        return response.sendStatus(400);
    }

    if (sanitize(file) !== file) {
        console.error('Malicious filename prevented');
        return response.sendStatus(403);
    }

    if (config.disableThumbnails == true) {
        const pathToOriginalFile = path.join(getOriginalFolder(type), file);
        return response.sendFile(pathToOriginalFile, { root: __dirname });
    }

    const pathToCachedFile = await generateThumbnail(type, file);

    if (!pathToCachedFile) {
        return response.sendStatus(404);
    }

    return response.sendFile(pathToCachedFile, { root: __dirname });
});

/* OpenAI */
app.post("/getstatus_openai", jsonParser, function (request, response_getstatus_openai = response) {
    if (!request.body) return response_getstatus_openai.sendStatus(400);
    api_key_openai = request.body.key;
    const api_url = new URL(request.body.reverse_proxy || api_openai).toString();
    const args = {
        headers: { "Authorization": "Bearer " + api_key_openai }
    };
    client.get(api_url + "/models", args, function (data, response) {
        if (response.statusCode == 200) {
            console.log(data);
            response_getstatus_openai.send(data);//data);
        }
        if (response.statusCode == 401) {
            console.log('Access Token is incorrect.');
            response_getstatus_openai.send({ error: true });
        }
        if (response.statusCode == 404) {
            console.log('Endpoint not found.');
            response_getstatus_openai.send({ error: true });
        }
        if (response.statusCode == 500 || response.statusCode == 501 || response.statusCode == 501 || response.statusCode == 503 || response.statusCode == 507) {
            console.log(data);
            response_getstatus_openai.send({ error: true });
        }
    }).on('error', function (err) {
        response_getstatus_openai.send({ error: true });
    });
});

app.post("/openai_bias", jsonParser, async function (request, response) {
    if (!request.body || !Array.isArray(request.body))
        return response.sendStatus(400);

    let result = {};

    const tokenizer = tiktoken.encoding_for_model(request.query.model);

    for (const entry of request.body) {
        if (!entry || !entry.text) {
            continue;
        }

        const tokens = tokenizer.encode(entry.text);

        for (const token of tokens) {
            result[token] = entry.value;
        }
    }

    tokenizer.free();
    return response.send(result);
});

// Shamelessly stolen from Agnai
app.post("/openai_usage", jsonParser, async function (request, response) {
    if (!request.body) return response.sendStatus(400);
    const key = request.body.key;
    const api_url = new URL(request.body.reverse_proxy || api_openai).toString();

    const headers = {
        'Content-Type': 'application/json',
        Authorization: `Bearer ${key}`,
    };

    const date = new Date();
    date.setDate(1);
    const start_date = date.toISOString().slice(0, 10);

    date.setMonth(date.getMonth() + 1);
    const end_date = date.toISOString().slice(0, 10);

    try {
        const res = await getAsync(
            `${api_url}/dashboard/billing/usage?start_date=${start_date}&end_date=${end_date}`,
            { headers },
        );
        return response.send(res);
    }
    catch {
        return response.sendStatus(400);
    }
});

app.post("/generate_openai", jsonParser, function (request, response_generate_openai) {
    if (!request.body) return response_generate_openai.sendStatus(400);
    const api_url = new URL(request.body.reverse_proxy || api_openai).toString();

    const controller = new AbortController();
    request.socket.on('close', function () {
        controller.abort();
    });

    console.log(request.body);
    const config = {
        method: 'post',
        url: api_url + '/chat/completions',
        headers: {
            'Content-Type': 'application/json',
            'Authorization': 'Bearer ' + api_key_openai
        },
        data: {
            "messages": request.body.messages,
            "model": request.body.model,
            "temperature": request.body.temperature,
            "max_tokens": request.body.max_tokens,
            "stream": request.body.stream,
            "presence_penalty": request.body.presence_penalty,
            "frequency_penalty": request.body.frequency_penalty,
            "stop": request.body.stop,
            "logit_bias": request.body.logit_bias
        },
        signal: controller.signal,
    };

    if (request.body.stream)
        config.responseType = 'stream';

    axios(config)
        .then(function (response) {
            if (response.status <= 299) {
                if (request.body.stream) {
                    console.log("Streaming request in progress")
                    response.data.pipe(response_generate_openai);
                    response.data.on('end', function () {
                        console.log("Streaming request finished");
                        response_generate_openai.end();
                    });
                } else {
                    response_generate_openai.send(response.data);
                    console.log(response.data);
                    console.log(response.data?.choices[0]?.message);
                }
            } else if (response.status == 400) {
                console.log('Validation error');
                response_generate_openai.send({ error: true });
            } else if (response.status == 401) {
                console.log('Access Token is incorrect');
                response_generate_openai.send({ error: true });
            } else if (response.status == 402) {
                console.log('An active subscription is required to access this endpoint');
                response_generate_openai.send({ error: true });
            } else if (response.status == 500 || response.status == 409 || response.status == 504) {
                if (request.body.stream) {
                    response.data.on('data', chunk => {
                        console.log(chunk.toString());
                    });
                } else {
                    console.log(response.data);
                }
                response_generate_openai.send({ error: true });
            }
        })
        .catch(function (error) {
            if (error.response) {
                if (request.body.stream) {
                    error.response.data.on('data', chunk => {
                        console.log(chunk.toString());
                    });
                } else {
                    console.log(error.response.data);
                }
            }
            try {
                response_generate_openai.send({ error: true });
            } catch (error) {
                console.error(error);
            }
        });
});

app.post("/tokenize_openai", jsonParser, function (request, response_tokenize_openai = response) {
    if (!request.body) return response_tokenize_openai.sendStatus(400);

    const tokensPerName = request.query.model.includes('gpt-4') ? 1 : -1;
    const tokensPerMessage = request.query.model.includes('gpt-4') ? 3 : 4;
    const tokensPadding = 3;

    const tokenizer = tiktoken.encoding_for_model(request.query.model);

    let num_tokens = 0;
    for (const msg of request.body) {
        num_tokens += tokensPerMessage;
        for (const [key, value] of Object.entries(msg)) {
            num_tokens += tokenizer.encode(value).length;
            if (key == "name") {
                num_tokens += tokensPerName;
            }
        }
    }
    num_tokens += tokensPadding;

    tokenizer.free();

    response_tokenize_openai.send({ "token_count": num_tokens });
});

app.post("/savepreset_openai", jsonParser, function (request, response) {
    const name = sanitize(request.query.name);
    if (!request.body || !name) {
        return response.sendStatus(400);
    }

    const filename = `${name}.settings`;
    const fullpath = path.join(directories.openAI_Settings, filename);
    fs.writeFileSync(fullpath, JSON.stringify(request.body), 'utf-8');
    return response.send({ name });
});

app.post("/tokenize_llama", jsonParser, async function (request, response) {
    if (!request.body) {
        return response.sendStatus(400);
    }

    const count = await countTokensLlama(request.body.text);
    return response.send({ count });
});

// ** REST CLIENT ASYNC WRAPPERS **
function deleteAsync(url, args) {
    return new Promise((resolve, reject) => {
        client.delete(url, args, (data, response) => {
            if (response.statusCode >= 400) {
                reject(data);
            }
            resolve(data);
        }).on('error', e => reject(e));
    })
}

function putAsync(url, args) {
    return new Promise((resolve, reject) => {
        client.put(url, args, (data, response) => {
            if (response.statusCode >= 400) {
                reject(data);
            }
            resolve(data);
        }).on('error', e => reject(e));
    })
}

function postAsync(url, args) {
    return new Promise((resolve, reject) => {
        client.post(url, args, (data, response) => {
            if (response.statusCode >= 400) {
                reject([data, response]);
            }
            resolve(data);
        }).on('error', e => reject(e));
    })
}

function getAsync(url, args) {
    return new Promise((resolve, reject) => {
        client.get(url, args, (data, response) => {
            if (response.statusCode >= 400) {
                reject(data);
            }
            resolve(data);
        }).on('error', e => reject(e));
    })
}
// ** END **

const tavernUrl = new URL(
    (cliArguments.ssl ? 'https://' : 'http://') +
    (listen ? '0.0.0.0' : '127.0.0.1') +
    (':' + server_port)
);

const autorunUrl = new URL(
    (cliArguments.ssl ? 'https://' : 'http://') +
    ('127.0.0.1') +
    (':' + server_port)
);

const setupTasks = async function () {
    ensurePublicDirectoriesExist();
    await ensureThumbnailCache();

    // Colab users could run the embedded tool
    if (!is_colab) await convertWebp();

    await spp.load(`./src/sentencepiece/tokenizer.model`);

    console.log('Launching...');

    if (autorun) open(autorunUrl.toString());
    console.log('SillyTavern is listening on: ' + tavernUrl);
    if (listen &&
        !config.whitelistMode &&
        !config.basicAuthMode)
        console.log('Your SillyTavern is currently open to the public. To increase security, consider enabling whitelisting or basic authentication.')
}

if (true === cliArguments.ssl)
    https.createServer(
        {
            cert: fs.readFileSync(cliArguments.certPath),
            key: fs.readFileSync(cliArguments.keyPath)
        }, app)
        .listen(
            tavernUrl.port,
            tavernUrl.hostname,
            setupTasks
        );
else
    http.createServer(app).listen(
        tavernUrl.port,
        tavernUrl.hostname,
        setupTasks
    );

async function convertWebp() {
    const files = fs.readdirSync(directories.characters).filter(e => e.endsWith(".webp"));

    if (!files.length) {
        return;
    }

    console.log(`${files.length} WEBP files will be automatically converted.`);

    for (const file of files) {
        try {
            const source = path.join(directories.characters, file);
            const dest = path.join(directories.characters, path.basename(file, ".webp") + ".png");

            if (fs.existsSync(dest)) {
                console.log(`${dest} already exists. Delete ${source} manually`);
                continue;
            }

            console.log(`Read... ${source}`);
            const data = await charaRead(source);

            console.log(`Convert... ${source} -> ${dest}`);
            await webp.dwebp(source, dest, "-o");

            console.log(`Write... ${dest}`);
            await charaWrite(dest, data, path.parse(dest).name);

            console.log(`Remove... ${source}`);
            fs.rmSync(source);
        } catch (err) {
            console.log(err);
        }
    }
}

function ensurePublicDirectoriesExist() {
    for (const dir of Object.values(directories)) {
        if (!fs.existsSync(dir)) {
            fs.mkdirSync(dir, { recursive: true });
        }
    }
}