using System;
using System.IO;
using System.Net.Http;
using System.Security.Cryptography;
using System.Text;
using System.Text.Json;
using System.Threading.Tasks;

class Program
{
    private static readonly byte[] Key = Encoding.UTF8.GetBytes("XRemote1234Secure5678Key90123456"); 
    private static readonly byte[] IV = Encoding.UTF8.GetBytes("XRemoteIV1234567");

    public static string DecryptString(string cipherText)
    {
        byte[] buffer = Convert.FromBase64String(cipherText);
        using (Aes aesAlg = Aes.Create())
        {
            aesAlg.Key = Key;
            aesAlg.IV = IV;
            var decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
            using (var msDecrypt = new MemoryStream(buffer))
            {
                using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (var srDecrypt = new StreamReader(csDecrypt))
                    {
                        return srDecrypt.ReadToEnd();
                    }
                }
            }
        }
    }

    static async Task Main()
    {
        try {
            Console.WriteLine("START...");
            string cipherText = "0xU4AtyuN12/2fO5aR3z4kKk1mZ2z+x/2XnLqJkY+oA2H9SmlGg/gTx+qk/fJzCcZQufgtujjxrcFIVTARjSA==";
            string configUrl = DecryptString(cipherText);
            Console.WriteLine("URL: '" + configUrl + "'");
            
            using var http = new HttpClient();
            Console.WriteLine("Fetching...");
            var resp = await http.GetAsync(configUrl);
            Console.WriteLine("Status: " + resp.StatusCode);
            
            string json = await resp.Content.ReadAsStringAsync();
            Console.WriteLine("JSON size: " + json.Length);
            
            using var doc = JsonDocument.Parse(json);
            if (doc.RootElement.TryGetProperty("ApiBaseUrl", out var apiUrl))
            {
                Console.WriteLine("API URL: " + apiUrl.GetString());
            }
            Console.WriteLine("SUCCESS!");
        } catch (Exception ex) {
            Console.WriteLine("Error: " + ex.ToString());
        }
    }
}