using System.Threading.Tasks;
using Xunit;
using XWorld.Framework.Protocol;
using XWorld.Server.Gateway;

namespace XWorld.Server.Gateway.Tests
{
    public class GatewayEndToEndTests
    {
        private static Frame JoinRps()
            => new Frame(Channel.Framework, (ushort)FrameworkOpcode.MatchRequest,
                new MatchRequestMsg { GameId = "rps", Version = 1 }.Encode());

        [Fact]
        public async Task Heartbeat_IsEchoedBack()
        {
            var host = new GameServerHost();
            await host.StartAsync(TestGames.Root, tickIntervalMs: 20);
            try
            {
                using var client = new WsTestClient();
                await client.ConnectAsync(host.WsBaseUrl, pid: 7);
                await client.SendFrameAsync(new Frame(Channel.Framework, (ushort)FrameworkOpcode.Heartbeat,
                    new HeartbeatMsg { ClientTimeMs = 999L }.Encode()));

                Frame? echo = null;
                for (int i = 0; i < 10; i++)
                {
                    var f = await client.ReceiveFrameAsync(5000);
                    if (f.Channel == Channel.Framework && f.Opcode == (ushort)FrameworkOpcode.Heartbeat) { echo = f; break; }
                }
                Assert.True(echo.HasValue, "未收到心跳回显");
                Assert.Equal(999L, HeartbeatMsg.Decode(echo.Value.Payload).ClientTimeMs);
                await client.CloseAsync();
            }
            finally { await host.StopAsync(); }
        }

        [Fact]
        public async Task Reconnect_ContinuesReceivingFromSameRoom()
        {
            var host = new GameServerHost();
            // matchTimeoutTicks=3 → 单人后 AI 兜底成团；logicalDt=0.2 让 60s 对局慢跑；大重连窗口
            await host.StartAsync(TestGames.Root, tickIntervalMs: 200,
                reconnectWindowTicks: 100, matchTimeoutTicks: 3, logicalDt: 0.2f);
            try
            {
                var client1 = new WsTestClient();
                await client1.ConnectAsync(host.WsBaseUrl, pid: 42);
                await client1.SendFrameAsync(JoinRps());

                // 收到 MatchFound 后的第一个游戏快照
                bool gotSnapshot = false;
                for (int i = 0; i < 15 && !gotSnapshot; i++)
                {
                    var f = await client1.ReceiveFrameAsync(5000);
                    if (f.Channel == Channel.Game) gotSnapshot = true;
                }
                Assert.True(gotSnapshot, "重连前应先收到一个快照");

                // 断开
                await client1.CloseAsync();
                client1.Dispose();

                // 用同 pid 重连
                using var client2 = new WsTestClient();
                await client2.ConnectAsync(host.WsBaseUrl, pid: 42);

                // 房间仍在跑，下一个房间输出应发到 client2
                bool gotAfterReconnect = false;
                for (int i = 0; i < 15 && !gotAfterReconnect; i++)
                {
                    var f = await client2.ReceiveFrameAsync(5000);
                    if (f.Channel == Channel.Game) gotAfterReconnect = true;
                    else if (f.Channel == Channel.Framework && f.Opcode == (ushort)FrameworkOpcode.RoomEnd) gotAfterReconnect = true;
                }
                Assert.True(gotAfterReconnect, "重连后应继续收到房间输出（快照或 RoomEnd）");
                await client2.CloseAsync();
            }
            finally { await host.StopAsync(); }
        }
    }
}