const crypto = require('crypto');
const fs = require('fs');
const args = process.argv.slice(2);

var credentials = { algorithm: "aes128", password: "594492b14a59184b6775f8b29a6cc73c" };

function encrypt(data) {
    var cipher = crypto.createCipher(credentials.algorithm, credentials.password);
    return cipher.update(data, 'utf8', 'hex') + cipher.final('hex');
}

function decrypt(data) {
    var cipher = crypto.createDecipher(credentials.algorithm, credentials.password);
    return cipher.update(data, 'hex', 'utf8') + cipher.final('utf8');
}


if(args[0]=="crypt"){
    fs.readFile(args[1], 'utf8', function(err, data) {
        if (err) throw err;
        fs.writeFile(args[2], encrypt(data), function(err) {
            if(err) {
                return console.log(err);
            }
        });
    });
}else if(args[0]=="decrypt"){
    fs.readFile(args[1], 'utf8', function(err, data) {
        if (err) throw err;
        fs.writeFile(args[2], decrypt(data), function(err) {
            if(err) {
                return console.log(err);
            }
        });
    });
}else{
    console.log("Usage: source dist");
}