using System.Collections.Generic;
using System.Text;
using Fighter3D.Core;
using Fighter3D.Server;
using XWorld.Framework;
using XWorld.Framework.Protocol;
using XWorld.Server.Host;

namespace XWorld.Server.Host.Tests
{
    public class Fighter3DServerRoomTests
    {
        private sealed class FakeOutput : IRoomOutput
        {
            public readonly List<NetMessage> Broadcasts = new List<NetMessage>();
            public void Broadcast(NetMessage message) => Broadcasts.Add(message);
            public void SendTo(int playerId, NetMessage message) { }
        }

        private static readonly IReadOnlyList<PlayerInfo> TwoHumans = new[]
        {
            new PlayerInfo { PlayerId = 10, Name = "A", IsAI = false },
            new PlayerInfo { PlayerId = 20, Name = "B", IsAI = false },
        };

        private static (RoomCtx Ctx, FakeOutput Output, bool[] Ended, RoomEndResult[] Result) BuildCtx()
        {
            var output = new FakeOutput();
            var ended = new bool[1];
            var result = new RoomEndResult[1];
            var ctx = new RoomCtx(
                new DeterministicRandom(42),
                new ManualClock(),
                new ConsoleLogger(),
                new InMemoryStorage(),
                output,
                r => { ended[0] = true; result[0] = r; });

            return (ctx, output, ended, result);
        }

        private static NetMessage ControlsMsg(int axis, FighterButtons buttons)
        {
            var writer = new PacketWriter();
            writer.WriteVarInt(axis);
            writer.WriteByte((byte)buttons);
            return new NetMessage(FighterServerRoom.InputOpcode, writer.ToArray());
        }

        private static FighterState LastSnapshot(FakeOutput output)
        {
            var last = output.Broadcasts[output.Broadcasts.Count - 1];
            Assert.Equal(FighterServerRoom.SnapshotOpcode, last.Opcode);
            return new FighterLogic().Decode(last.Payload);
        }

        [Fact]
        public void OnRoomStart_BroadcastsInitialSnapshot()
        {
            var (ctx, output, _, _) = BuildCtx();
            var room = new FighterServerRoom();

            room.OnRoomStart(TwoHumans, ctx);

            Assert.NotEmpty(output.Broadcasts);
            var snapshot = LastSnapshot(output);
            Assert.Equal(FighterPhase.Running, snapshot.Phase);
        }

        [Fact]
        public void RepeatedHeavyAttacks_CanKoAndEndRoomWithWinnerPid()
        {
            var (ctx, output, ended, result) = BuildCtx();
            var room = new FighterServerRoom();
            room.OnRoomStart(TwoHumans, ctx);

            room.OnMessage(10, ControlsMsg(0, FighterButtons.Heavy));
            for (int i = 0; i < 800 && !ended[0]; i++)
                room.OnTick(1f / 20f);

            Assert.True(ended[0]);
            Assert.NotNull(result[0]);
            Assert.Equal(10, result[0].WinnerPlayerId);
            Assert.Contains("Fighter3D", Encoding.UTF8.GetString(result[0].ResultBlob));

            var snapshot = LastSnapshot(output);
            Assert.Equal(FighterPhase.Finished, snapshot.Phase);
            Assert.Equal(0, snapshot.WinnerSeat);
        }
    }
}