'use strict';

var v4 = require('aws-signature-v4');
var xml2js = require('xml2js');
var parseString = xml2js.parseString;
parseString = require('util').promisify(parseString);
var builder = new xml2js.Builder();

var request = require('@root/request');
//request.debug = false;

var defaults = {
	baseUri: '/2013-04-01/'
};

module.exports.create = function(config) {
	var baseUri = defaults.baseUri.replace(/\/$/, '');
	var key = config.key;
	var secret = config.secret;

	function api(method, path, body, query) {
		var body = body || '';
		var query = query || {};
		var options = { 
			key: key, 
			secret: secret, 
			query: query 
		};
		
		if(method === 'POST') {
			options.headers = { 'Content-Type': 'application/xml' }
		}

		var url = v4.createPresignedURL(method, 'route53.amazonaws.com', path, 'route53', body, options);
		//console.log('url: ' + url + '\n');

		var parameters = {
			method: method,
			url: url
		};

		if(method === 'POST') {
			parameters.headers = { 'Content-Type': 'application/xml' }
		}

		if(body) {
			parameters.body = body;
		}

		// console.log(method, path, query);

		return request(parameters).then(function(response) {
			if (response.statusCode < 200 || response.statusCode >= 300) {
				console.error(response.statusCode, options.url);
				console.error();
				console.error('Request:');
				console.error(options);
				console.error();
				console.error('Response:');
				console.error(response.body);
				console.error();
				throw new Error(
					'Error response. Check token, baseUri, domains, etc.'
				);
			}
			return response;
		});
	}

	/*
	api('GET', baseUri + '/' + 'hostedzone').then(function(response){
		console.log('######## RESPONSE #########');

	});
	*/

	return {
		init: function(options) {
			request = options.request;
			return null;
		},
		zones: function(data) {		
			//console.info('List Zones', data);
			return api('GET', baseUri + '/' + 'hostedzone').then(function(response){
				return parseString(response.body).then(function(body){
					var zones = body.ListHostedZonesResponse.HostedZones[0].HostedZone.map(function(element) {
						return element.Name[0].replace(/\.$/, ''); // all route 53 domains terminate with a dot
					});

					return zones;
				});
			});
			
		},
		set: function(data) {
			// console.info('Add TXT', data);
			// console.log('data: ' + JSON.stringify(data, null, 2));
			var challenge = data.challenge;

			if (!challenge.dnsZone) {
				throw new Error('No matching zone for ' + challenge.dnsHost);
			}

			return api('GET', baseUri + '/' + 'hostedzonesbyname', null, 'dnsname=' + challenge.dnsZone + '&maxitems=1')
						.then(function(response){
							return parseString(response.body).then(function(body){
								return body;
								});		
						})
						.then(function(body){
							var zoneID =  body.ListHostedZonesByNameResponse.HostedZones[0].HostedZone[0].Id[0];
							var xmlns =  body.ListHostedZonesByNameResponse.$.xmlns;
							
							var parameters = {
								'ChangeResourceRecordSetsRequest': {
									'$': {
										'xmlns': xmlns
									},
									'ChangeBatch': [
										{
											'Changes': [
												{
													'Change': [
														{
															'Action': [
																'CREATE'
															],
															'ResourceRecordSet': [
																{
																	'Type': [
																		'TXT'
																	],
																	'Name': [
																		challenge.dnsHost // AWS requires FQDN
																	],
																	'ResourceRecords': [
																		{
																			'ResourceRecord': [
																				{
																					'Value': [
																						'"' + challenge.dnsAuthorization + '"' // value must be surrounded by double quotes
																					]
																				}
																			]
																		}
																	],
																	'TTL': [
																		300
																	]
																}
															]
															
														}
													]
												}
											]
										}
									]
								}
							}; 

							// By default AWS creates record sets with simple routing policy, so duplicates are not allowed.
							// A workaround is put the record sets in different weighted policies.   
							if(challenge.identifier.value.startsWith('foo')) {
								if(challenge.wildcard) {
									
									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].Weight = [
										1
									];

									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].SetIdentifier = [
										'wildcard'
									];
								} else {
									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].Weight = [
										1
									];

									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].SetIdentifier = [
										'subdomain'
									];
								}				
							}

							var xml = builder.buildObject(parameters);
							//console.log('xml: ' + xml);

							return api('POST', baseUri + zoneID + '/rrset/', xml);
	
						});

			
		},
		get: function(data) {
			// console.info('List TXT', data);
			var challenge = data.challenge;

			return api('GET', baseUri + '/' + 'hostedzonesbyname', null, 'dnsname=' + challenge.dnsZone + '&maxitems=1')
						.then(function(response){
							return parseString(response.body).then(function(body){
								return body;
								});		
						})
						.then(function(body){
							var zoneID =  body.ListHostedZonesByNameResponse.HostedZones[0].HostedZone[0].Id[0];
							// console.log('zoneID: ' + zoneID);
							return zoneID;
						})
						.then(function(zoneID){
							// GET /2013-04-01/hostedzone/Id/rrset?identifier=StartRecordIdentifier&maxitems=MaxItems&name=StartRecordName&type=StartRecordType HTTP/1.1
							
							return api('GET', baseUri + '/' + zoneID + '/rrset', null, 'name=' + challenge.dnsPrefix + '.' + challenge.dnsZone + '.' + '&type=TXT')
							.then(function(response){
								return parseString(response.body).then(function(body){
										if (body.ListResourceRecordSetsResponse.ResourceRecordSets[0] === '') return null;
										
										var record = body.ListResourceRecordSetsResponse.ResourceRecordSets[0].ResourceRecordSet.filter(function(element){
											return (
												element.ResourceRecords[0].ResourceRecord[0].Value[0].replace(/\"/g, '') === challenge.dnsAuthorization &&
												element.Name[0].includes(challenge.dnsPrefix)
											);
										})[0];

										if (record) {
											return { dnsAuthorization: record.ResourceRecords[0].ResourceRecord[0].Value[0].replace(/\"/g, '') };
										}
						
										return null;
									});		
							});
									
						});
		
		},
		remove: function(data) {
			// console.info('Remove TXT', data);

			var challenge = data.challenge;

			return api('GET', baseUri + '/' + 'hostedzonesbyname', null, 'dnsname=' + challenge.dnsZone + '&maxitems=1')
						.then(function(response){
							return parseString(response.body).then(function(body){
								return body;
								});		
						})
						.then(function(body){
							var zoneID =  body.ListHostedZonesByNameResponse.HostedZones[0].HostedZone[0].Id[0];
							var xmlns =  body.ListHostedZonesByNameResponse.$.xmlns;
							
							var parameters = {
								'ChangeResourceRecordSetsRequest': {
									'$': {
										'xmlns': xmlns
									},
									'ChangeBatch': [
										{
											'Changes': [
												{
													'Change': [
														{
															'Action': [
																'DELETE'
															],
															'ResourceRecordSet': [
																{
																	'Type': [
																		'TXT'
																	],
																	'Name': [
																		challenge.dnsHost // AWS requires FQDN
																	],
																	'ResourceRecords': [
																		{
																			'ResourceRecord': [
																				{
																					'Value': [
																						'"' + challenge.dnsAuthorization + '"' // value must be surrounded by double quotes
																					]
																				}
																			]
																		}
																	],
																	'TTL': [
																		300
																	]
																}
															]
															
														}
													]
												}
											]
										}
									]
								}
							}; 

							if(challenge.identifier.value.startsWith('foo')) {
								if(challenge.wildcard) {
									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].Weight = [
										1
									];

									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].SetIdentifier = [
										'wildcard'
									];
								} else {
									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].Weight = [
										1
									];

									parameters.ChangeResourceRecordSetsRequest.ChangeBatch[0].Changes[0].Change[0].ResourceRecordSet[0].SetIdentifier = [
										'subdomain'
									];
								}				
							}

							var xml = builder.buildObject(parameters);
							// console.log('\n', xml, '\n');
							
							return api('POST', baseUri + zoneID + '/rrset/', xml);
	
						});

		}
		
	}
	
};