How to use the jsthemis.SecureCellSeal function in jsthemis

if (process.argv.length < 5 || process.argv.length > 6) {
    console.log('Usage:    ');
    process.exit(1);
}

var command = process.argv[2];
var key = new Buffer(process.argv[3]);
var message = process.argv[4];
var context = undefined;
if(process.argv.length === 6){
    var context = new Buffer(process.argv[5]);
}

if (command === "enc"){
    var message_buf = new Buffer(message);
    var encrypter = new jsthemis.SecureCellSeal(key);
    if (context){
        var result = encrypter.encrypt(message_buf, context);
    } else {
        var result = encrypter.encrypt(message_buf);
    }
    console.log(result.toString('base64'));
    process.exit(0)
} else if (command === 'dec'){
    var decrypter = new jsthemis.SecureCellSeal(key);
    var decoded_message = new Buffer(message, 'base64');
    if(context){
        var result = decrypter.decrypt(decoded_message, context);
    } else {
        var result = decrypter.decrypt(decoded_message);
    }
    console.log(result.toString('ascii'));

if(process.argv.length === 6){
    var context = new Buffer(process.argv[5]);
}

if (command === "enc"){
    var message_buf = new Buffer(message);
    var encrypter = new jsthemis.SecureCellSeal(key);
    if (context){
        var result = encrypter.encrypt(message_buf, context);
    } else {
        var result = encrypter.encrypt(message_buf);
    }
    console.log(result.toString('base64'));
    process.exit(0)
} else if (command === 'dec'){
    var decrypter = new jsthemis.SecureCellSeal(key);
    var decoded_message = new Buffer(message, 'base64');
    if(context){
        var result = decrypter.decrypt(decoded_message, context);
    } else {
        var result = decrypter.decrypt(decoded_message);
    }
    console.log(result.toString('ascii'));
    process.exit(0)
} else {
    console.log('Wrong command, use "enc" or "dec"');
    process.exit(1)
}

var addon = require('jsthemis');


if(process.argv.length==5){
    command=process.argv[2];
    password=new Buffer.from(process.argv[3]);

    seal = new addon.SecureCellSeal(password);
    if(command=="enc"){
	console.log(seal.encrypt(new Buffer.from(process.argv[4])).toString("base64"));
    }else if(command=="dec"){
	console.log(seal.decrypt(new Buffer.from(process.argv[4], "base64")).toString());
    }else{
	console.log("usage node secure_cell.js   ");
    }
}else{
    console.log("usage node secure_cell.js   ");
}

create_acrastruct: function(data, acra_public_key, context){
	var data_buffer = Buffer.isBuffer(data)?data:(new Buffer(data));
	var context_buffer = Buffer.isBuffer(context)?context:(new Buffer(context));
	var random_keypair = new themis.KeyPair();
	var sm = new themis.SecureMessage(random_keypair.private(), acra_public_key);
	var random_key = crypto.randomBytes(32);
	var wrapped_random_key = sm.encrypt(random_key);
	var sc = new themis.SecureCellSeal(random_key);
	crypto.randomFillSync(random_key);
	var encrypted_data = context?sc.encrypt(data_buffer, context_buffer):sc.encrypt(data_buffer);
	var begin_tag = new Buffer([34,34,34,34,34,34,34,34]);
	var encrypted_data_length = new int64(encrypted_data.length).toBuffer();
	return Buffer.concat([begin_tag, random_keypair.public(), wrapped_random_key, encrypted_data_length, encrypted_data]);
    }