using System;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Reflection;
using System.Threading;
using System.Threading.Tasks;
using Jellyfin.Data.Enums;
using Jellyfin.Plugin.Enigma2;
using MediaBrowser.Common.Configuration;
using MediaBrowser.Controller.Entities;
using MediaBrowser.Controller.Library;
using MediaBrowser.Controller.LiveTv;
using MediaBrowser.Model.Serialization;
using Microsoft.Extensions.Logging.Abstractions;

public static class SavedChannelPlaybackTests
{
    public const string Old = "1:0:1:3D66:2C88:13E:820000:0:0:0:";
    public const string Current = "1:0:1:13F1:5DC:13E:820000:0:0:0:";
    public static async Task Run(Action<bool,string> check)
    {
        var previous = Plugin.Instance;
        var folder = Path.Combine(Path.GetTempPath(),"saved-channel-"+Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(folder);
        try
        {
            var paths=DispatchProxy.Create<IApplicationPaths,SavedPaths>();((SavedPaths)(object)paths).Folder=folder;
            var plugin=new Plugin(paths,DispatchProxy.Create<IXmlSerializer,NoXmlFiles>());
            plugin.Configuration.HostName="receiver";plugin.Configuration.WebInterfacePort="80";
            plugin.Configuration.StreamingPort="8001";plugin.Configuration.OnlyOneBouquet=true;
            plugin.Configuration.TVBouquet="Polskie";plugin.Configuration.FetchPiconsFromWebInterface=true;
            var library=DispatchProxy.Create<ILibraryManager,SavedChannelLibrary>();
            var handler=new ReceiverHandler();
            using var relay=new LiveStreamRelay(new HttpClient(handler),8096,TimeSpan.FromMilliseconds(50));
            var calls=0;
            var probe=new LiveStreamProbe((url,token)=>
            {
                calls++;
                check(url.EndsWith("?programme=5105",StringComparison.Ordinal),"saved channel probes the migrated SID rather than the historical SID");
                return Task.FromResult("{\"programs\":[{\"program_id\":5105,\"streams\":[{\"index\":0,\"codec_type\":\"video\",\"codec_name\":\"h264\",\"width\":1920,\"height\":1080}]}],\"streams\":[{\"index\":0,\"codec_type\":\"video\",\"codec_name\":\"h264\",\"width\":1920,\"height\":1080}]}");
            });
            var service=new LiveTvService(NullLogger<LiveTvService>.Instance,new ReceiverFactory(),null,probe,relay,library);
            var saved=await service.GetChannelStream(Old,null,CancellationToken.None);
            var current=await service.GetChannelStream(Current,null,CancellationToken.None);
            check(saved.Path==current.Path&&calls==1,"saved and current native channels share the same relay and metadata probe");
            check(((SavedChannelLibrary)(object)library).Calls==1,"current reference avoids the native historical lookup");
            var id=saved.Path.Split('/').Last();
            await using var first=await relay.Subscribe(id,CancellationToken.None);
            await using var second=await relay.Subscribe(id,CancellationToken.None);
            await first.Reader.ReadAsync();await second.Reader.ReadAsync();
            check(handler.Calls==1&&handler.Reference==Current,"both native IDs open only one upstream using the migrated receiver reference");
            using var cancelled=new CancellationTokenSource();cancelled.Cancel();
            try { await service.GetChannelStream(Old,null,cancelled.Token);throw new Exception("Expected cancellation"); }
            catch(OperationCanceledException) { check(handler.Calls==1,"cancelled channel lookup opens no extra upstream"); }
        }
        finally
        {
            typeof(Plugin).GetProperty(nameof(Plugin.Instance)).SetValue(null,previous);
            Directory.Delete(folder,true);
        }
    }

    public class NoXmlFiles:DispatchProxy
    {
        protected override object Invoke(MethodInfo method,object[] args)
        {
            if(method.Name=="SerializeToFile")return null; // Keep default configuration in memory.
            throw new Exception("No persisted configuration expected in isolated test");
        }
    }
    public class SavedPaths:DispatchProxy
    {
        public string Folder;
        protected override object Invoke(MethodInfo method,object[] args) => method.ReturnType==typeof(string)?Folder:null;
    }
    public class SavedChannelLibrary:DispatchProxy
    {
        public int Calls;
        protected override object Invoke(MethodInfo method,object[] args)
        {
            if(method.Name!="GetItemList"||args[0] is not InternalItemsQuery q||!q.IncludeItemTypes.SequenceEqual(new[]{BaseItemKind.LiveTvChannel}))
                throw new Exception("Expected metadata lookup restricted to live TV channels");
            Calls++;
            return new BaseItem[]{new LiveTvChannel{ExternalId=Old,Name="TV PULS HD",ServiceName="Enigma2"},
                new LiveTvChannel{ExternalId=Old,Name="Different channel",ServiceName="Other provider"}};
        }
    }
    private sealed class ReceiverFactory:IHttpClientFactory
    {
        public HttpClient CreateClient(string name)=>new(new BouquetHandler());
    }
    private sealed class BouquetHandler:HttpMessageHandler
    {
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,CancellationToken token)
        {
            token.ThrowIfCancellationRequested();
            var body=string.IsNullOrEmpty(request.RequestUri.Query)
                ? "<e2servicelist><e2service><e2servicereference>1:7:1:0:0:0:0:0:0:0:FROM BOUQUET</e2servicereference><e2servicename>Polskie</e2servicename></e2service></e2servicelist>"
                : "<e2servicelist><e2service><e2servicereference>"+Current+"</e2servicereference><e2servicename>TV PULS HD</e2servicename></e2service></e2servicelist>";
            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK){Content=new StringContent(body)});
        }
    }
    private sealed class ReceiverHandler:HttpMessageHandler
    {
        public int Calls;public string Reference;
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,CancellationToken token)
        {
            Calls++;Reference=request.RequestUri.AbsolutePath.TrimStart('/');
            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK){Content=new StreamContent(new PacketStream())});
        }
    }
}