var net = require('net');
var http = require('http');
var url = require('url');
var fs = require('fs');
var cluster = require('cluster');

var ip_mapping = require('./ip_mapping');

function process_command(data, callback) {
    var command = {command: "", data: ""};
    var data_split = data.trim().toLowerCase().split(' ');
    command.command = data_split[0];
    command.data = data_split[1];
    switch (command.command) {
        case 'get':
            var ip = command.data;
            if (net.isIPv4(ip) == false) {
                callback("CLIENT_ERROR\r\n");
                break;
            }
            var location = ip_mapping.query_ip(ip);
            if (location == undefined) location = "UNKNOWN";
            var result_buffer = new Buffer(location);
            var result = "VALUE "+command.data+" 0 "+result_buffer.length+"\r\n";
            result += location+"\r\nEND\r\n";
            callback(result);
            break;
        case 'quit':
            callback(false);
            break;
        default:
            callback("CLIENT_ERROR\r\n");
            break;
    }
}

var server = net.createServer(function(conn) {
    conn.on('data', function(data) {
        data = data.toString();
        process_command(data, function(result) {
            if (result == false) {
                conn.end();
            } else {
                conn.write(result);
            }
        })
    });
});

var http_server = http.createServer(function(req, res) {
    res.setHeader("Connection", "close");
    var url_parts = url.parse(req.url);
    var ip = url_parts.query;
    if (!ip || net.isIPv4(ip) == false) {
        res.end('ERROR');
        return;
    }
    var location = ip_mapping.query_ip(ip);
    res.end(location);
});

ip_mapping.build_mapping(__dirname + '/city.ip.csv', __dirname + '/contry.ip.csv');


if (cluster.isMaster) {
    for (var i = 0; i < 1; i++) {
        cluster.fork();
    }
    cluster.on('death', function(worker) {
        console.log('worker ' + worker.pid + ' died');
    });
} else {
    server.listen(8421);
    http_server.listen(8420);
}