BringTYTDBack/Program.cs

using System.Collections.Concurrent;
using Renci.SshNet;
using YoutubeExplode;
using YoutubeExplode.Videos;
using Tesses.WebServer;
using static Creds;
using System.Diagnostics.CodeAnalysis;
using YoutubeExplode.Playlists;
using YoutubeExplode.Channels;

YoutubeClient ytc=new YoutubeClient();
ConcurrentStack<VideoId> videoIds=new ConcurrentStack<VideoId>();
bool isRunning=true;

async Task AddVideo(VideoId id)
{
    SshClient client = new SshClient(IP,Username,Password);
    await client.ConnectAsync(default);
    using(var res=client.CreateCommand($"echo {DirectoryOnServer}/*-{id.Value}.mp4"))
    {
        await res.ExecuteAsync();
    
        if(res.Result == $"{DirectoryOnServer}/*-{id.Value}.mp4\n")
        {
             using(var res2=client.CreateCommand($"cd {DirectoryOnServer} && tytd {id.Value}"))
            {
                await res2.ExecuteAsync();
                Console.WriteLine($"Downloaded: https://www.youtube.com/watch?v={id.Value}");
                _=res2.Result;
            }         
        }
        else
        {
            Console.WriteLine($"Video already exists: https://www.youtube.com/watch?v={id.Value}");
        }

        
    }
   
}

async Task AddItem(string url)
{
    VideoId? vId = VideoId.TryParse(url);
    PlaylistId? pId = PlaylistId.TryParse(url);
    ChannelId? cId = ChannelId.TryParse(url);
    UserName? username = UserName.TryParse(url); 
    ChannelSlug? slug = ChannelSlug.TryParse(url);  
    ChannelHandle? handle = ChannelHandle.TryParse(url);

    if(url.Length == 11 && vId.HasValue)    
    {
        videoIds.Push(vId.Value);
    }
    else if(pId.HasValue)
    {
        await foreach(var v in ytc.Playlists.GetVideosAsync(pId.Value))
        {
            videoIds.Push(v.Id);
        }
    }
    else if(vId.HasValue)
    {
        videoIds.Push(vId.Value);
    }
    else if(cId.HasValue)
    {
        await foreach(var c in ytc.Channels.GetUploadsAsync(cId.Value))
        {
            videoIds.Push(c.Id);
        }
    }
    else if(username.HasValue)
    {
        cId = (await ytc.Channels.GetByUserAsync(username.Value)).Id;
        await foreach(var c in ytc.Channels.GetUploadsAsync(cId.Value))
        {
            videoIds.Push(c.Id);
        }
    }
    else if(slug.HasValue)
    {
        cId = (await ytc.Channels.GetBySlugAsync(slug.Value)).Id;
        await foreach(var c in ytc.Channels.GetUploadsAsync(cId.Value))
        {
            videoIds.Push(c.Id);
        }
    }
    else if(handle.HasValue)
    {
        cId = (await ytc.Channels.GetByHandleAsync(handle.Value)).Id;
        await foreach(var c in ytc.Channels.GetUploadsAsync(cId.Value))
        {
            videoIds.Push(c.Id);
        }
    }
}

Task.Factory.StartNew(async()=>{
    while(isRunning)
    {
        if(videoIds.TryPop(out var res))
        {
            await AddVideo(res);
        }
    }
},TaskCreationOptions.LongRunning).Wait(0);

MountableServer msvr=new MountableServer(new StaticServer("wwwroot"));

msvr.Mount("/api/AddItemRes/1/",new TYTDServer(AddItem));
msvr.Mount("/api/AddItem/",new TYTDServer(AddItem));
msvr.Mount("/api/AddVideoRes/1/",new TYTDServer(videoIds));
msvr.Mount("/api/AddVideo/",new TYTDServer(videoIds));
RouteServer routeServer=new RouteServer(msvr);
routeServer.Add("/itemsInQueue",async(ctx)=>{
    await ctx.SendJsonAsync(videoIds.Count);
});
routeServer.Add("/add",async(ctx)=>{
    if(ctx.QueryParams.TryGetFirst("v",out var v))
    {
        await AddItem(v);
    }
    await ctx.SendRedirectAsync("/");
});
routeServer.StartServer(3252);

public class TYTDServer : Server
{
    bool onlyVideos;
    ConcurrentStack<VideoId>? stk;
   
    Func<string,Task>? cb;
    public TYTDServer(ConcurrentStack<VideoId> stk)
    {
        onlyVideos=true;
        this.stk = stk;
    }

    public TYTDServer(Func<string,Task> cb)
    {
        onlyVideos=false;
        this.cb = cb;
    }
    public override async Task GetAsync(ServerContext ctx)
    {
        if(onlyVideos)
        {
            string url=ctx.UrlPath.Substring(1);
            stk?.Push(url);
            await ctx.SendTextAsync("<script>window.history.back();</script>");
        }
        else
        {
            if(cb == null) {
                await ctx.SendTextAsync("<script>window.history.back();</script>");
      
                return;
            }
            string url=ctx.UrlPath.Substring(1);
            await cb(url);
            await ctx.SendTextAsync("<script>window.history.back();</script>");

        }
    }
}