const fs = require('fs');
const QrCode = require('qrcode-reader');
const { Jimp } = require('jimp');

async function qrscanner(buffer) {
    return new Promise(async (resolve, reject) => {
        try {
            const image = await Jimp.read(buffer);
            const qr = new QrCode();
            
            qr.callback = (err, value) => {
                if (err) {
                    reject(err);
                } else {
                    resolve(value.result);
                }
            };
            
            qr.decode(image.bitmap);
        } catch (error) {
            reject(error);
        }
    });
}

// Usage:
qrscanner(fs.readFileSync('./ex/qrcode.jpg')).then(console.log);