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

namespace JAuth
{
    public class api
    {
        public string Name { get; set; }
        public string OwnerId { get; set; }
        public string Version { get; set; }
        public string Url { get; set; }
        public string SessionId { get; private set; }
        public string ErrorMessage { get; private set; }
        public JsonElement ResponseData { get; private set; }

        private static readonly HttpClient client = new HttpClient();

        public api(string name, string ownerid, string version, string url = "https://jauth.site/api/v1/")
        {
            Name = name;
            OwnerId = ownerid;
            Version = version;
            Url = url.TrimEnd('/');
        }

        public static string GetSafeHWID()
        {
            try
            {
                string raw = Environment.MachineName + "_" + Environment.UserName;
                using (SHA256 sha = SHA256.Create())
                {
                    byte[] hash = sha.ComputeHash(Encoding.UTF8.GetBytes(raw));
                    return BitConverter.ToString(hash).Replace("-", "").ToLower();
                }
            }
            catch
            {
                return "HWID_FALLBACK";
            }
        }

        public async Task<bool> InitAsync()
        {
            try
            {
                var payload = new { name = Name, ownerid = OwnerId, version = Version };
                var content = new StringContent(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");
                var res = await client.PostAsync($"{Url}/init", content);
                var json = await res.Content.ReadAsStringAsync();
                using var doc = JsonDocument.Parse(json);
                bool success = doc.RootElement.GetProperty("success").GetBoolean();
                if (success && doc.RootElement.TryGetProperty("sessionid", out var s))
                {
                    SessionId = s.GetString();
                }
                return success;
            }
            catch (Exception ex)
            {
                ErrorMessage = ex.Message;
                return false;
            }
        }

        public async Task<bool> LicenseAsync(string key)
        {
            try
            {
                var payload = new {
                    name = Name,
                    ownerid = OwnerId,
                    key = key.Trim(),
                    hwid = GetSafeHWID(),
                    sessionid = SessionId
                };
                var content = new StringContent(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");
                var res = await client.PostAsync($"{Url}/license", content);
                var json = await res.Content.ReadAsStringAsync();
                using var doc = JsonDocument.Parse(json);
                bool success = doc.RootElement.GetProperty("success").GetBoolean();
                if (success && doc.RootElement.TryGetProperty("info", out var info))
                {
                    ResponseData = info.Clone();
                }
                else if (doc.RootElement.TryGetProperty("message", out var msg))
                {
                    ErrorMessage = msg.GetString();
                }
                return success;
            }
            catch (Exception ex)
            {
                ErrorMessage = ex.Message;
                return false;
            }
        }
    }
}