using Infrastructure.Extensions;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Sockets;
using System.Security.Cryptography;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;

namespace IoT.Shared.DeviceServices.Onvif
{
    public class OnvifDeviceManagement : IOnvifDeviceManagement, IDisposable
    {
        private readonly IHttpClientFactory _httpClientFactory;
        private readonly object thisLock = new object();
        private readonly UdpClient _client = new UdpClient();
        private readonly CancellationTokenSource _tokenSource = new CancellationTokenSource();
        public Action<IPCamera> Callback { get; set; }

        public OnvifDeviceManagement(IHttpClientFactory httpClientFactory)
        {
            this._httpClientFactory = httpClientFactory;
            Task.Run(() =>
            {
                try
                {
                    var ep = new IPEndPoint(IPAddress.Any, 3702);
                    while (!_tokenSource.IsCancellationRequested)
                    {
                        if (_client.Available > 0)
                        {
                            var buffer = _client.Receive(ref ep);
                            var result = Encoding.UTF8.GetString(buffer);
                            var camera = new IPCamera { DiscoveryXml = result };
                            try
                            {
                                camera.ParseDiscovery();
                                camera.GetCapabilitiesXml = GetCapabilities(camera.DeviceUrl);
                                camera.ParseCapabilities();
                                this.Callback(camera);
                            }
                            catch (Exception ex)
                            {
                                ex.PrintStack();
                            }
                        }
                        Thread.Sleep(1);
                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }, _tokenSource.Token);
            Console.WriteLine("OnvifDeviceManagement init complete");
        }

        public void Discovery()
        {
            Console.WriteLine("search onvif devices...");
            var list = new ConcurrentBag<string>();
            lock (thisLock)
            {
                try
                {
                    var probeMessage = string.Format(Template.GetServiceRequestTemplage, Guid.NewGuid());
                    var message = Encoding.UTF8.GetBytes(probeMessage);
                    _client.Send(message, message.Length, new IPEndPoint(IPAddress.Parse("239.255.255.250"), 3702));
                }
                catch (Exception ex)
                {
                    ex.PrintStack();
                }
            }
        }

        public string GetCapabilities(string deviceUrl)
        {
            return SoapRequest(deviceUrl, Template.GetCapabilitiesAction, Template.GetCapabilitiesMessage);
        }

        public string GetProfiles(string deviceUrl, string mediaUrl)
        {
            return SoapRequest(mediaUrl, Template.GetProfilesAction, string.Format(Template.Templage, Template.GetProfilesMessageBody));
        }

        public string GetProfiles(string deviceUrl, string mediaUrl, string userName, string password)
        {
            return RequestXml(mediaUrl, Template.GetProfilesAction, Template.GetProfilesMessageBody, userName, password, GetOnoce(deviceUrl));
        }

        public string GetStreamUri(string deviceUrl, string mediaUrl, string token)
        {
            return SoapRequest(mediaUrl, Template.GetStreamUriAction, string.Format(Template.Templage, String.Format(Template.GetStreamUriMessage, token)));
        }

        public string GetStreamUri(string deviceUrl, string mediaUrl, string userName, string password, string token)
        {
            return RequestXml(mediaUrl, Template.GetStreamUriAction, String.Format(Template.GetStreamUriMessage, token), userName, password, GetOnoce(deviceUrl));
        }

        public string GetSnapshotUri(string deviceUrl, string mediaUrl, string token)
        {
            return SoapRequest(mediaUrl, Template.GetSnapshotUriAction, string.Format(Template.Templage, String.Format(Template.GetSnapshotUriMessage, token)));
        }

        public string GetSnapshotUri(string deviceUrl, string mediaUrl, string userName, string password, string token)
        {
            return RequestXml(mediaUrl, Template.GetSnapshotUriAction, String.Format(Template.GetSnapshotUriMessage, token), userName, password, GetOnoce(deviceUrl));
        }

        private string SoapRequest(string url, string action, string message)
        {
            var hc = this._httpClientFactory.CreateClient();
            hc.DefaultRequestHeaders.Add("ContentType", $"application/soap+xml; charset=utf-8; action=\"{action}\"");
            var task = hc.PostAsync(url, new StringContent(message));
            var result = task.Result;
            var content = result.Content.ReadAsStringAsync().Result;
            return result.StatusCode == HttpStatusCode.OK ? content : "";
        }

        private string RequestXml(string url, string action, string body, string userName, string password, string onoce)
        {
            var nonce_b = Convert.FromBase64String(onoce);
            var now = DateTime.Now.ToUniversalTime().ToString("yyyy-MM-ddThh:mm:ss.fffZ");
            var creationtime_b = Encoding.ASCII.GetBytes(now);
            var password_b = Encoding.ASCII.GetBytes(password);
            var concatenation_b = new byte[nonce_b.Length + creationtime_b.Length + password_b.Length];
            Buffer.BlockCopy(nonce_b, 0, concatenation_b, 0, nonce_b.Length);
            Buffer.BlockCopy(creationtime_b, 0, concatenation_b, nonce_b.Length, creationtime_b.Length);
            Buffer.BlockCopy(password_b, 0, concatenation_b, nonce_b.Length + creationtime_b.Length, password_b.Length);
            var sha = new SHA1CryptoServiceProvider();
            var pdresult = sha.ComputeHash(concatenation_b);
            var passworddigest = Convert.ToBase64String(pdresult);
            var message = string.Format(Template.AuthTemplate, userName, passworddigest, Convert.ToBase64String(nonce_b), now, body);
            var result = SoapRequest(url, action, message);
            return result;
        }

        private string GetOnoce(string deviceUrl)
        {
            var message = @"<s:Envelope xmlns:s=""http://www.w3.org/2003/05/soap-envelope"">
                                                      <s:Body xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema"">
                                                        <GetDeviceInformation xmlns=""http://www.onvif.org/ver10/device/wsdl""></GetDeviceInformation>
                                                      </s:Body>
                                                    </s:Envelope>";
            var hc = this._httpClientFactory.CreateClient();
            hc.DefaultRequestHeaders.Add("ContentType", $"application/soap+xml; charset=utf-8; action=\"{Template.GetDeviceInformationAction}\"");
            var task = hc.PostAsync(deviceUrl, new StringContent(message));
            var result = task.Result.Headers.WwwAuthenticate;
            return Regex.Match(result.ToString(), "nonce=\"([^\"]+)\"").Groups[1].Value;
        }

        public void Dispose()
        {
            this._tokenSource.Cancel();
            this._client.Dispose();
        }
    }
}