using System.Net;
using System.Text;
using System.Windows;

using Flurl.Http;

using Newtonsoft.Json;

using Szmedi.AIScriptRunner.Properties;
using Szmedi.AIScriptRunner.Web;

namespace Szmedi.AIScriptRunner.Services
{
    public class AuthenticationService
    {

        private string GetStreamReader(string url, string postData, string auth = "", int timeout = 60000, string encode = "utf-8", string contentType = "application/json", string method = "POST")
        {
            var data = Encoding.GetEncoding(encode).GetBytes(postData);
            var webRequest = (HttpWebRequest)WebRequest.Create(url);

            if (!string.IsNullOrWhiteSpace(auth))
            {
                var athu = "Authorization:" + auth;
                var whc = new WebHeaderCollection();
                whc.Add(athu);
                webRequest.Headers.Add(whc);
            }
            webRequest.Method = method;
            webRequest.ContentType = contentType + ";" + encode;
            webRequest.ContentLength = data.Length;
            webRequest.Timeout = timeout;
            var requestStream = webRequest.GetRequestStream();
            requestStream.Write(data, 0, data.Length);
            var webResponse = (HttpWebResponse)webRequest.GetResponse();
            var responseStream = webResponse.GetResponseStream();
            if (responseStream == null) { return string.Empty; }
            var streamReader = new StreamReader(responseStream, Encoding.GetEncoding(encode));
            return streamReader.ReadToEnd();
        }

        public async Task<ResponseVO> LoginAsync(string username, string password)
        {
            try
            {
                // 1. 取公钥
                var keyJson = await Settings.Default.PublicKeyUrl.GetStringAsync();
                var pubKeyVO = JsonConvert.DeserializeObject<PublicKeyVO>(keyJson);
                if (pubKeyVO?.Successful == true)
                {
                    // 2. 用 BouncyCastle 加密
                    var encrypted = RSAHelper.EncryptByJavaKey(pubKeyVO.Data.PublicKey, $"{password}");
                    
                    var jsonData = $"{{\"accountName\":\"{username}\",\"password\":\"{encrypted}\",\"uuid\":\"{pubKeyVO.Data.UUID}\",\"appVersion\":\"newversion\"}}";
                    // 3. 发送登录请求
                    var respones = GetStreamReader(Settings.Default.LoginUrl, jsonData);
                    var settings = new JsonSerializerSettings
                    {
                        MissingMemberHandling = MissingMemberHandling.Ignore
                    };

                    return JsonConvert.DeserializeObject<ResponseVO>(respones, settings);
                }
                else
                {
                    MessageBox.Show("获取不到用户公钥信息,请联系管理员");
                    return null;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return null;
            }
        }
    }
}