src/reflex/scanners.ts

// eslint-disable-next-line @typescript-eslint/ban-ts-comment
// @ts-ignore
import * as us from "unscan";
import fetch from "node-fetch";
import { writeFileSync } from "fs";
import generateFileName from "../utils/temp/generateFileName.js";
import Tesseract from "node-tesseract-ocr";
import type Discord from "discord.js";

interface NSFWSchema { nsfw: boolean }
interface MalwareSchema { safe: boolean }

export async function testNSFW(link: string): Promise<NSFWSchema> {
    const p = await saveAttachment(link);
    const result = await us.nsfw.file(p);
    return result;
}

export async function testMalware(link: string): Promise<MalwareSchema> {
    const p = await saveAttachment(link);
    const result = await us.malware.file(p);
    return result;
}

export async function saveAttachment(link: string): Promise<string> {
    const image = (await (await fetch(link)).buffer()).toString("base64");
    const fileName = generateFileName((link.split("/").pop() as string).split(".").pop() as string);
    writeFileSync(fileName, image, "base64");
    return fileName;
}

export async function testLink(link: string): Promise<{safe: boolean, tags: string[]}> {
    return await us.link.scan(link);
}


const linkTypes = {
    "PHISHING": "Links designed to trick users into clicking on them.",
    "DATING": "Dating sites.",
    "TRACKERS": "Websites that store or track personal information.",
    "ADVERTISEMENTS": "Websites only for ads.",
    "FACEBOOK": "Facebook pages. (Facebook has a number of dangerous trackers. Read more on /privacy)",
    "AMP": "AMP pages. (AMP is a technology that allows websites to be served by Google. Read more on /privacy)",
    "FACEBOOK TRACKERS": "Websites that include trackers from Facebook.",
    "IP GRABBERS": "Websites that store your IP address, which shows your approximate location.",
    "PORN": "Websites that include pornography.",
    "GAMBLING": "Gambling sites, often scams.",
    "MALWARE": "Websites which download files designed to break or slow down your device.",
    "PIRACY": "Sites which include illegally downloaded material.",
    "RANSOMWARE": "Websites which download a program that can steal your data and make you pay to get it back.",
    "REDIRECTS": "Sites like bit.ly which could redirect to a malicious site.",
    "SCAMS": "Sites which are designed to trick you into doing something.",
    "TORRENT": "Websites that download torrent files.",
    "HATE": "Websites that spread hate towards groups or individuals.",
    "JUNK": "Websites that are designed to make you waste time."
};
export { linkTypes };


export async function LinkCheck(message: Discord.Message): Promise<string[]> {
    const links = message.content.match(/https?:\/\/(www\.)?[-a-zA-Z0-9@:%._+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_+.~#?&//=]*)/gi) ?? [];
    const detections: {tags: string[], safe: boolean}[] = [];
    const promises: Promise<void>[] = links.map(async element => {
        let returned;
        try {
            if (element.match(/https?:\/\/[a-zA-Z]+\.?discord(app)?\.(com|net)\/?/)) return; // Also matches discord.net, not enough of a bug
            returned = await testLink(element);
        } catch {
            detections.push({tags: [], safe: true});
            return;
        }
        if (returned) { detections.push({tags: returned.tags || [], safe: returned.safe}); }
        else { detections.push({tags: [], safe: true}); }
    });
    await Promise.all(promises);
    const detectionsTypes = detections.map(element => {
        const type = Object.keys(linkTypes).find(type => element.tags.includes(type));
        if (type) return type;
        // if (!element.safe) return "UNSAFE"
        return undefined;
    }).filter(element => element !== undefined);
    return detectionsTypes as string[];
}

export async function NSFWCheck(element: string): Promise<boolean> {
    try {
        const test = (await testNSFW(element));
        return test.nsfw;
    } catch {
        return false;
    }
}

export async function SizeCheck(element: {height: number | null, width: number | null}): Promise<boolean> {
    if (element.height === null || element.width === null) return true;
    if (element.height < 20 || element.width < 20) return false;
    return true;
}

export async function MalwareCheck(element: string): Promise<boolean> {
    try {
        return (await testMalware(element)).safe;
    } catch {
        return true;
    }
}

export function TestString(string: string, soft: string[], strict: string[]): object | null {
    for(const word of strict || []) {
        if (string.toLowerCase().includes(word)) {
            return {word: word, type: "strict"};
        }
    }
    for(const word of soft) {
        for(const word2 of string.match(/[a-z]+/gi) || []) {
            if (word2 === word) {
                return {word: word, type: "strict"};
            }
        }
    }
    return null;
}

export async function TestImage(url: string): Promise<string | null> {
    const text = await Tesseract.recognize(url, {lang: "eng", oem: 1, psm: 3});
    return text;
}