global using System;
global using System.Collections.Generic;
global using System.Threading;
global using System.Threading.Tasks;
global using Meum.Core;
using System.Net;
using System.Net.Quic;
using System.Net.Security;
using DTLib.Logging;

namespace Meum.Client;

public class Client
{
    private readonly HashSet<ServerConnection> _connectedServers = new();
    private readonly ILogger _logger;

    public Client(ILogger logger)
    {
        _logger = logger;
    }

    public IReadOnlySet<ServerConnection> ConnectedServers => _connectedServers;

    public UserAddress? Address { get; private set; }

    public Task RegisterAsync(UserAddress address)
    {
        return Task.CompletedTask;
    }
    
    public Task LogInAsync(UserAddress address)
    {
        if(Address != null)
            throw new InvalidOperationException("Already logged in");
        Address = address;
        return Task.CompletedTask;
    }
    
    public async Task<ServerConnection> ConnectToServerAsync(DnsEndPoint serverEndPoint, CancellationToken ct = default)
    {
        var quicConn = await QuicConnection.ConnectAsync(new QuicClientConnectionOptions
        {
            // TODO serverEndPoint
            RemoteEndPoint = new IPEndPoint(IPAddress.Loopback, Constants.ServerPortDefault),
            DefaultStreamErrorCode = Constants.DefaultStreamErrorCode,
            DefaultCloseErrorCode = Constants.DefaultCloseErrorCode,
            ClientAuthenticationOptions = new SslClientAuthenticationOptions
            {
                ApplicationProtocols = Constants.ApplicationProtocols,
                TargetHost = serverEndPoint.Host
            }
        }, ct);
        
        var timeOutCts = CancellationTokenSource.CreateLinkedTokenSource(ct);
        timeOutCts.CancelAfter(Constants.ConnectionTimeout);
        var serv = await ServerConnection.OpenAsync(quicConn,
            serverEndPoint,
            _logger,
            timeOutCts.Token);
        
        if(!_connectedServers.Add(serv))
            throw new Exception($"Is already connected to server '{serverEndPoint.Host}'");
        return serv;
    }
}