'use strict';

const zlib = require('zlib');
const crypto = require('crypto');

const { DOMParser, XMLSerializer } = require('xmldom');
const xpath = require('xpath');

const DEFAULT_IV = Buffer.from(Array(16).fill(0, 0, 15));
module.exports = class Response {
	constructor(client, data) {
		this.client = client;
		this.doc = new DOMParser().parseFromString(data, 'text/xml');
	}

	isSegmented() {
		const select = xpath.useNamespaces({ xmlns: 'urn:org:ebics:H004' });
		const node = select('//xmlns:header/xmlns:mutable/xmlns:SegmentNumber', this.doc);

		return !!node.length;
	}

	isLastSegment() {
		const select = xpath.useNamespaces({ xmlns: 'urn:org:ebics:H004' });
		const node = select("//xmlns:header/xmlns:mutable/*[@lastSegment='true']", this.doc);

		return !!node.length;
	}

	orderData() {
		const orderData = this.doc.getElementsByTagNameNS('urn:org:ebics:H004', 'OrderData')[0].textContent;
		const decipher = crypto.createDecipheriv('aes-128-cbc', this.transactionKey(), DEFAULT_IV).setAutoPadding(false);
		const data = Buffer.from(decipher.update(orderData, 'base64', 'binary') + decipher.final('binary'), 'binary');

		return zlib.inflateSync(data).toString();
	}

	transactionKey() {
		const keyNodeText = this.doc.getElementsByTagNameNS('urn:org:ebics:H004', 'TransactionKey')[0].textContent;
		const tkEncrypted = Buffer.from(keyNodeText, 'base64');

		this.client.e().key.setOptions({ encryptionScheme: 'pkcs1' });

		return this.client.e().key.decrypt(tkEncrypted);
	}

	transactionId() {
		const select = xpath.useNamespaces({ xmlns: 'urn:org:ebics:H004' });
		const node = select('//xmlns:header/xmlns:static/xmlns:TransactionID', this.doc);

		return node.length ? node[0].textContent : '';
	}

	toXML() {
		return new XMLSerializer().serializeToString(this.doc);
	}
};