using System;

using System.Collections.Generic;

using System.Linq;

​

class RegionMapper

{

    public static Dictionary<string, string> RegionByCountryMap = new Dictionary<string, string>( StringComparer.OrdinalIgnoreCase )

    {

        { "RUS", "ru" },

        { "ABH", "ab" },

        { "BLR", "by" },

​

        { "ISR", "il" },

        { "MDA", "md" },

        { "DEU", "de" },

        { "CHE", "ch" },

        { "CZE", "cz" },

        { "ITA", "it" },

        { "TUR", "tr" },

        { "FIN", "fn" },

        { "GEO", "ge" },

        { "MNE", "me" },

        { "BGR", "bg" },

        { "GRC", "gr" },

        { "ROU", "ro" },

        { "SWE", "se" },

        { "FRA", "fr" },

        { "ESP", "es" },

        { "LVA", "lv" },

        { "AZE", "az" },

        { "MCO", "mc" },

        { "UKR", "ua" },

        { "ALB", "al" },

        { "AUT", "at" },

        { "CYP", "cy" },

        { "DNK", "dk" },

        { "EST", "ee" },

        { "HUN", "hu" },

        { "LTU", "lt" },

        { "NOR", "no" },

        { "POL", "pl" },

        { "PRT", "pt" },

        { "SVN", "si" },

​

        { "NAM", "na" },

        { "SYC", "sc" },

​

        { "USA", "us" },

        { "CAN", "ca" },

​

        { "THA", "th" },

        { "TUN", "tn" },

        { "MYS", "my" },

        { "IDN", "id" },

        { "SGP", "sg" },

        { "UZB", "uz" },

        { "KAZ", "kz" },

        { "ARM", "am" },

        { "KGZ", "kg" },

        { "TJK", "tj" },

        { "AFG", "af" },

        { "ARE", "ae" },

        { "IND", "in" },

        { "JOR", "jo" },

        { "KHM", "kh" },

        { "MDV", "mv" },

        { "VNM", "vn" }

    };

​

    public static Dictionary<string, string[]> RegionByProxyMap = new Dictionary<string, string[]>( StringComparer.OrdinalIgnoreCase )

    {

        { "ru", new[] {

            "ru", "ab", "by"

        } },

        { "eu", new[] {

            "il", "md", "de", "ch", "cz", "it", "tr", "fn", "ge", "me", "bg", "gr",

            "ro", "se", "fr", "es", "lv", "az", "mc", "ua", "al", "at", "cy", "dk",

            "ee", "hu", "lt", "no", "pl", "pt", "si", "na", "sc"

        } },

        { "us", new[] {

            "us", "ca"

        } },

        { "asia", new[] {

            "th", "tn", "my", "id", "sg", "uz", "kz", "am", "kg", "tj", "af", "ae",

            "in", "jo", "kh", "mv", "vn"

        } }

    };

​

    public static Dictionary<string, string[]> RegionCodeByTopLevelDomainsMap = new Dictionary<string, string[]>( StringComparer.OrdinalIgnoreCase )

    {

        { "ru", new[] {

            "ru"

        } },

        { "asia", new[] {

            "eu", "us", "asia"

        } }

    };

​

    public static Dictionary<string, string> RegionCodeByDefaultTopLevelDomainMap = new Dictionary<string, string>( StringComparer.OrdinalIgnoreCase )

    {

        { "ru", "ru" },

        { "asia", "eu" }

    };

​

    public static string GetHost( string env, string countryCode, string regionCode )

    {

        if ( env == "qa" && regionCode == "ru" )

        {

            return "www.qatl.ru";

        }

​

        if ( env == "qa2" && regionCode == "asia" )

        {

            return "www.qatl2.ru";

        }

​

        string topLevelDomain;

        if ( !RegionCodeByDefaultTopLevelDomainMap.TryGetValue( regionCode, out topLevelDomain ) )

        {

            topLevelDomain = "com";

        }

        string secondLevelDomain = "tlintegration";

        string thirdLevelDomain = "ibe";

​

        if ( RegionByCountryMap.ContainsKey( countryCode ) )

        {

            string countryRegion = RegionByCountryMap[ countryCode ];

            string proxy = RegionByProxyMap.First( code => code.Value.Contains( countryRegion ) ).Key;

            List<string> allowedRegionCodes = RegionCodeByTopLevelDomainsMap

                .Where( code => code.Value.Contains( proxy ) )

                .Select( pair => pair.Key )

                .ToList();

​

            if ( allowedRegionCodes.Contains( regionCode ) )

            {

                topLevelDomain = proxy;

                thirdLevelDomain = countryRegion + "-" + thirdLevelDomain;

            }

        }

​

        return $"{thirdLevelDomain}.{secondLevelDomain}.{topLevelDomain}";

    }

}

​

public class Program

{

    private static List<List<string>> TestCases = new List<List<string>>

    {

        new List<string> { "qa", "RUS", "ru", "www.qatl.ru" },

        new List<string> { "qa2", "RUS", "asia", "www.qatl2.ru" },

        new List<string> { "prod", "USA", "asia", "us-ibe.tlintegration.us" },

        new List<string> { "prod", "USA", "ru", "ibe.tlintegration.ru" },

        new List<string> { "prod", "ABH", "asia", "ibe.tlintegration.eu" },

        new List<string> { "prod", "ABH", "ru", "ab-ibe.tlintegration.ru" },

    };

​

    public static void Main()

    {

        foreach ( List<string> testCase in TestCases )

        {

            string host = RegionMapper.GetHost(testCase[0], testCase[1], testCase[2]);

            if ( host != testCase[3] )

            {

                Console.WriteLine($"{testCase[0]}, {testCase[1]}, {testCase[2]}, → {host}, expected: {testCase[3]}");

            }

        }

    }

}