var winston = require('winston');
var crypto = require('crypto');
var xml = require('xml');
var url = require('url');

var config;
var callbackReport;
var aaa;
var logger;
var options;

function start(_config, _callbackReport, options) {
    config = _config;
    callbackReport = _callbackReport
    
    if (options && options.aaa) {
            aaa = options.aaa;
    }
    
    if (options && options.logger) {
        logger = options.logger;
    } else {
        logger = new winston.Logger({
            transports: [
              new (winston.transports.Console)()
            ]
        });
    }
}

function calculateSignature(params) {
    return crypto.createHash('sha256').update(
        params.trxtype + params.prdcode + params.value + params.msisdn + params.trxid + params.uid
    ).digest().toString('hex');    
}

function createXmlPayload(params) {
    return "<?xml version=\"1.0\" ?>\n" + xml({
        ciwaru: [
            {trxtype: params.trxtype},
            {prdcode: params.prdcode},
            {value: params.value},
            {msisdn: params.msisdn},
            {trxid: params.trxid},
            {uid: params.uid},
            {hash: calculateSignature(params)}
        ]
    });
}

function getSNFromMessage(message) {
    var sn_match = message.match(/SN (\w+) /);
    return sn_match[1];
}

function topupResponseHandler(body) {
    logger.info('Got reply from partner', {body: body});
    xml2js(body, function(err, result) {
        if (err) {
            logger.warn('XML parsing error', {err: err});
        }
        logger.info('XML message from partner', {result: result});
    });
}

function topupRequest(task, retry) {
    var remoteProduct = task.remoteProduct.split(',');
    
    var params = {
        trxtype: '01',
        prdcode: remoteProduct[0],
        value: remoteProduct[1],
        msisdn: task.destination,
        trxid: task.requestId,
        uid: config.h2h_out.userid,
    };
    
    var postBody = createXmlPayload(params);
    
    var partnerUrl = url.parse(config.h2h_out.partner);
    var postRequest = {
        host: partnerUrl.hostname,
        path: partnerUrl.path,
        port: partnerUrl.port,
        method: "POST",
        headers: {
            'Content-Type': 'text/xml',
            'Content-Length': Buffer.byteLength(postBody)
        }
    };
    
    logger.info('POST to partner', {postRequest: postRequest});
    var req = http.request(postRequest, function( res ) {
        
        logger.info('Status code: ' + res.statusCode );
        var buffer = "";
        res.on( "data", function( data ) { buffer = buffer + data; } );
        res.on( "end", function( data ) {             
                topupResponseHandler(buffer);
        });
    });
    
    req.on('error', function(e) {
        logger.warn('problem with request: ' + e.message);
        callbackReport(task['requestId'], '40', e.message);
    });

    req.write(postBody);
    req.end();
}

exports.start = start;
exports.topupRequest = topupRequest;
exports.calculateSignature = calculateSignature;
exports.createXmlPayload = createXmlPayload;
exports.getSNFromMessage = getSNFromMessage;