using System;
using System.IO;
using System.Net.WebSockets;
using System.Threading;
using System.Threading.Tasks;
using XWorld.Framework.Protocol;

namespace XWorld.Server.Gateway.Tests
{
    // 集成测试用 WS 客户端：连接、发帧、带超时收一帧并解码
    internal sealed class WsTestClient : IDisposable
    {
        private readonly ClientWebSocket _ws = new ClientWebSocket();

        public async Task ConnectAsync(string wsBaseUrl, int pid)
        {
            await _ws.ConnectAsync(new Uri($"{wsBaseUrl}/ws?pid={pid}"), CancellationToken.None);
        }

        public async Task SendFrameAsync(Frame frame)
        {
            byte[] bytes = FrameCodec.Encode(frame);
            await _ws.SendAsync(new ArraySegment<byte>(bytes), WebSocketMessageType.Binary, true, CancellationToken.None);
        }

        // 在 timeout 内收一条 WS 消息并解码为 Frame；超时抛 TimeoutException
        public async Task<Frame> ReceiveFrameAsync(int timeoutMs = 5000)
        {
            using var cts = new CancellationTokenSource(timeoutMs);
            var buf = new byte[8192];
            using var ms = new MemoryStream();
            WebSocketReceiveResult res;
            do
            {
                res = await _ws.ReceiveAsync(new ArraySegment<byte>(buf), cts.Token);
                if (res.MessageType == WebSocketMessageType.Close)
                    throw new InvalidOperationException("server closed");
                ms.Write(buf, 0, res.Count);
            } while (!res.EndOfMessage);
            return FrameCodec.Decode(ms.ToArray());
        }

        public async Task CloseAsync()
        {
            try { await _ws.CloseAsync(WebSocketCloseStatus.NormalClosure, "bye", CancellationToken.None); }
            catch { /* 忽略 */ }
        }

        public void Dispose() => _ws.Dispose();
    }
}