using System;
using System.Net.WebSockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace WebDesktopBackend.Extentions {
    public static class WebSocketExtentions {

        public static async Task SendMessage(this WebSocket socket, string message, Encoding encoding = null) {
            encoding ??= Encoding.Default;
            await socket.SendAsync(new ArraySegment<byte>(encoding.GetBytes(message)), WebSocketMessageType.Text, true, CancellationToken.None);
        }

        public static async Task<string> RecieveMessage(this WebSocket socket, Encoding encoding = null) {
            encoding ??= Encoding.Default;
            byte[] buffer = new byte[1024 * 4];
            var result = await socket.ReceiveAsync(new ArraySegment<byte>(buffer), CancellationToken.None);
            return encoding.GetString(new ArraySegment<byte>(buffer, 0, result.Count));
        }

        public static async Task<WebSocket> ConnectAsync(this ClientWebSocket socket, Uri endpoint) {
            await socket.ConnectAsync(endpoint, CancellationToken.None);
            return socket;
        }

        public static CancellationTokenSource AddMessageEventHandler(this WebSocket socket, Action<string> handler) {
            var source = new CancellationTokenSource();

            Task.Run(async () => {
                while (!socket.CloseStatus.HasValue) {
                    string msg = await socket.RecieveMessage();
                    handler.Invoke(msg);
                }
            }, source.Token);

            return source;
        }

    }
}