UplayNameChecker/src/R6dbAPI.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace UplayNameChecker
{
    public class R6dbAPI
    {
        private HttpClient httpClient = new HttpClient();
        private const string URI = "https://api.statsdb.net/r6/namecheck/";

        public async Task<bool> IsNameAvailable(string name)
        {
            try
            {
                var reqUri = URI + System.Net.WebUtility.UrlEncode(name);
                var timestamp = GetCurrentTimestamp();
                var apiKey = GenerateAuthToken(timestamp);

                HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, reqUri);
                request.Headers.Add("x-api-key", apiKey);
                request.Headers.Add("origin", "https://r6db.net");

                var response = await httpClient.SendAsync(request);
                return (await response.Content.ReadAsStringAsync()).Contains("exists\":false");
            }
            catch (Exception ex)
            {
                Log.Error($"Could not check name {name}: {ex.Message}");
                return false;
            }
        }

        public string GenerateAuthToken(ulong timestamp)
        {
            var seed = "a3d6b18fa919072d65d890c47b336f1f78fc11c4";
            var sTimestamp = timestamp.ToString();
            var code = "";

            for(int i = 0; i < sTimestamp.Length; i++)
            {
                var t = int.Parse(sTimestamp[i].ToString());
                var c = (int)seed[i % seed.Length];
                switch (t)
                {
                    case 0: break;
                    case 1:
                        c = c - 1;
                        break;
                        case 2:
                        c = c >> 1;
                        break;
                    case 3:
                        c = c << 1;
                        break;
                    case 4:
                        c = (int)Math.Pow(t, c % 4);
                        break;
                    case 5:
                        c = (int)Math.Round(Math.Sqrt(c));
                        break;
                    case 6:
                        c = c << t;
                        goto case 7;
                    case 7:
                        c = c - 12;
                        break;
                    case 8:
                        c = 0;
                        break;
                    default:
                        c = -69420;
                        break;
                }
                if (c == -69420) continue;
                code += c.ToString();
            }
            var str2 = "authscript:" + code + ":" + timestamp + $":{GetTodaysTimestamp()}";
            return Convert.ToBase64String(Encoding.UTF8.GetBytes(str2));
        }

        private ulong GetCurrentTimestamp()
        {
            return (ulong)DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1)).TotalSeconds;
        }

        private ulong GetTodaysTimestamp()
        {
            return (ulong)DateTime.Today.Subtract(new DateTime(1970, 1, 1)).TotalSeconds;
        }
    }
}