#!/usr/bin/env node
'use strict';

// EXAMPLE:
// node bin/dns-parse.js samples/a-0.mdns.bin

var path = require('path');
// pass a terminal arg
var filename = process.argv[2];
var outname = process.argv[3];

if (!filename || /(-h)|(--help)/.test(process.argv.join(' '))) {
	console.error('');
	console.error(
		'Accepts a DNS packet (binary or json), converts it, and then converts it back to verify the function of the parser and packer'
	);
	console.error('');
	console.error(
		'Usage: node bin/dns-test.js <path/to/sample.json|.bin> <path/to/sample.bin|.json>'
	);
	console.error(
		'Example: node bin/dns-test.js ./samples/services-0.mdns.json ./samples/services-0.mdns.bin'
	);
	process.exit(1);
	return;
}

var PromiseA = require('bluebird');
var fs = PromiseA.promisifyAll(require('fs'));
var dnsjs = require('../').DNSPacket;
var extname = path
	.extname(filename)
	.substr(1)
	.toLowerCase();

if ('json' !== extname && 'bin' !== extname) {
	console.error(
		'The file extension must end in .json or .bin (raw DNS packet)'
	);
	process.exit(3);
	return;
}

var hexdump = require('@root/hexdump');

function testJsonAsync(nb) {
	var packet = dnsjs.write(JSON.parse(nb.toString('ascii')));
	var str = hexdump(packet);
	console.info(str);
	var json = dnsjs.parse(packet);
	if (json.error) {
		console.error(json);
		process.exit(37);
		return;
	}

	console.info('[OK] JSON -> binary -> JSON');

	if (!outname) {
		console.warn('');
		console.warn(
			"Usage: node bin/dns-test.js '" +
				filename +
				"' './" +
				path
					.basename(filename)
					.replace(path.extname(filename), '.bin') +
				"'"
		);
		console.warn('');
		return;
	}

	fs.writeFileSync(outname, packet, null);
}

function testBinAsync(nb) {
	var bin = nb.buffer.slice(nb.byteOffset, nb.byteOffset + nb.byteLength);
	var json = dnsjs.parse(bin);
	if (json.error) {
		console.error(json);
		process.exit(38);
		return;
	}
	var bin2 = dnsjs.write(json);
	//var debugname = outname || path.basename(filename);
	//fs.writeFileSync(debugname.replace(path.extname(debugname), '.bin'), bin2, null);
	var json2 = dnsjs.parse(bin2);
	if (json2.error) {
		console.error(json2);
		process.exit(37);
		return;
	}

	var assert = require('assert');
	// EXPLANATION:
	// The strategy used for compression pointers has not yet been proven
	// as deterministic... and we don't implement them anyway, so this may not be the same
	json = JSON.parse(
		JSON.stringify(json)
			.replace(/,"labels":.*?\]/, '')
			.replace(/,"cpcount":\d+/, '')
	);
	json2 = JSON.parse(
		JSON.stringify(json2)
			.replace(/,"labels":.*?\]/, '')
			.replace(/,"cpcount":\d+/, '')
	);
	//json2 = JSON.parse(JSON.stringify(json2));
	try {
		assert.deepEqual(json, json2);
	} catch (e) {
		console.error('');
		console.error('Original');
		console.error(JSON.stringify(json, null, 2));
		console.error('');
		console.error('Converted');
		console.error(JSON.stringify(json2, null, 2));
		console.error('');
		process.exit(422);
		return;
	}

	console.info('[OK] binary -> JSON -> binary -> JSON');
	console.warn(
		'(compression pointer support needs to be improved in order to support direct bin -> JSON -> bin testing)'
	);

	if (!outname) {
		console.warn('');
		console.warn(
			"Usage: node bin/dns-test.js '" +
				filename +
				"' './" +
				path
					.basename(filename)
					.replace(path.extname(filename), '.json') +
				"'"
		);
		console.warn('');
		return;
	}

	fs.writeFileSync(outname, JSON.stringify(json, null, 2), null);
}

if ('json' === extname) {
	return fs.readFileAsync(filename, null).then(testJsonAsync);
}

if ('bin' === extname) {
	return fs.readFileAsync(filename, null).then(testBinAsync);
}