"use strict";

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

const Crypto = require("../../crypto/Crypto");

const { DOMParser, XMLSerializer } = require("@xmldom/xmldom");
const xpath = require("xpath");
const errors = require("./errors");

const DEFAULT_IV = Buffer.from(Array(16).fill(0, 0, 15));

const lastChild = (node) => {
	let y = node.lastChild;

	while (y.nodeType !== 1) y = y.previousSibling;

	return y;
};

module.exports = (xml, keys) => ({
	keys,
	doc: new DOMParser().parseFromString(xml, "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 orderDataNode = this.doc.getElementsByTagNameNS(
			"urn:org:ebics:H004",
			"OrderData"
		);

		if (!orderDataNode.length) return {};

		const orderData = orderDataNode[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);
	},

	transactionKey() {
		const keyNodeText = this.doc.getElementsByTagNameNS(
			"urn:org:ebics:H004",
			"TransactionKey"
		)[0].textContent;
		return Crypto.privateDecrypt(
			this.keys.e(),
			Buffer.from(keyNodeText, "base64")
		);
	},

	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 : "";
	},

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

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

	businessCode() {
		const select = xpath.useNamespaces({ xmlns: "urn:org:ebics:H004" });
		const node = select("//xmlns:body/xmlns:ReturnCode", this.doc);

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

	businessSymbol(code) {
		return errors.business[code].symbol;
	},

	businessShortText(code) {
		return errors.business[code].short_text;
	},

	businessMeaning(code) {
		return errors.business[code].meaning;
	},

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

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

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

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

	technicalShortText(code) {
		return errors.technical[code].short_text;
	},

	technicalMeaning(code) {
		return errors.technical[code].meaning;
	},

	bankKeys() {
		const orderData = this.orderData().toString();
		if (!Object.keys(orderData).length) return {};

		const doc = new DOMParser().parseFromString(orderData, "text/xml");
		const select = xpath.useNamespaces({ xmlns: "urn:org:ebics:H004" });
		const keyNodes = select("//xmlns:PubKeyValue", doc);
		const bankKeys = {};

		if (!keyNodes.length) return {};

		for (let i = 0; i < keyNodes.length; i++) {
			const type = lastChild(keyNodes[i].parentNode).textContent;
			const modulus = xpath.select(
				".//*[local-name(.)='Modulus']",
				keyNodes[i]
			)[0].textContent;
			const exponent = xpath.select(
				".//*[local-name(.)='Exponent']",
				keyNodes[i]
			)[0].textContent;

			const mod = Buffer.from(modulus, "base64");
			const exp = Buffer.from(exponent, "base64");
			bankKeys[`bank${type}`] = {
				mod,
				exp,
			};
		}

		return bankKeys;
	},

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