From a781d929968f5efa2789a16ee4cc7c5888f54c7e Mon Sep 17 00:00:00 2001
From: Syntriax <syntriax@gmail.com>
Date: Sun, 27 Jul 2025 18:55:32 +0300
Subject: [PATCH] feat: game start countdown added

---
 Shared/Behaviours/Ball.cs            | 16 ++++-
 Shared/Behaviours/PongGameStarter.cs | 96 ++++++++++++++++++++++++++++
 Shared/Behaviours/PongManager.cs     | 50 +++++++--------
 Shared/PongUniverse.cs               |  5 ++
 4 files changed, 140 insertions(+), 27 deletions(-)
 create mode 100644 Shared/Behaviours/PongGameStarter.cs

diff --git a/Shared/Behaviours/Ball.cs b/Shared/Behaviours/Ball.cs
index 82b53bd..a329ae3 100644
--- a/Shared/Behaviours/Ball.cs
+++ b/Shared/Behaviours/Ball.cs
@@ -1,11 +1,15 @@
+using Microsoft.Xna.Framework.Audio;
+using Microsoft.Xna.Framework.Content;
+
 using Syntriax.Engine.Core;
+using Syntriax.Engine.Integration.MonoGame;
 using Syntriax.Engine.Network;
 using Syntriax.Engine.Physics2D;
 using Syntriax.Engine.Systems.Tween;
 
 namespace Pong.Behaviours;
 
-public class Ball : Behaviour2D, IFirstFrameUpdate, IPhysicsUpdate, INetworkEntity,
+public class Ball : Behaviour2D, IFirstFrameUpdate, ILoadContent, IPhysicsUpdate, INetworkEntity,
     IPacketListenerClient<Ball.BallUpdatePacket>,
     IPacketListenerClient<Ball.BallResetPacket>
 {
@@ -19,6 +23,8 @@ public class Ball : Behaviour2D, IFirstFrameUpdate, IPhysicsUpdate, INetworkEnti
     private INetworkCommunicatorServer? networkServer = null;
     private ITween? networkTween = null;
 
+    private SoundEffect? bounceSoundEffect = null;
+
     public void FirstActiveFrame()
     {
         BehaviourController.GetRequiredBehaviour<ICollider2D>().OnCollisionDetected.AddListener(OnCollisionDetected);
@@ -28,6 +34,11 @@ public class Ball : Behaviour2D, IFirstFrameUpdate, IPhysicsUpdate, INetworkEnti
         networkServer = Universe.FindBehaviour<INetworkCommunicatorServer>();
     }
 
+    public void LoadContent(ContentManager content)
+    {
+        bounceSoundEffect = content.Load<SoundEffect>("Audio/Bounce");
+    }
+
     public void LaunchBall(Vector2D launchDirection)
     {
         ResetBall();
@@ -74,6 +85,9 @@ public class Ball : Behaviour2D, IFirstFrameUpdate, IPhysicsUpdate, INetworkEnti
         else
             Transform.Position = packet.Position;
 
+        if (RigidBody.Velocity.MagnitudeSquared >= .01f)
+            bounceSoundEffect?.Play();
+
         RigidBody.Velocity = packet.Velocity;
         physicsEngine2D.StepIndividual(RigidBody, sender.Ping);
     }
diff --git a/Shared/Behaviours/PongGameStarter.cs b/Shared/Behaviours/PongGameStarter.cs
new file mode 100644
index 0000000..d3b2114
--- /dev/null
+++ b/Shared/Behaviours/PongGameStarter.cs
@@ -0,0 +1,96 @@
+using Microsoft.Xna.Framework.Audio;
+using Microsoft.Xna.Framework.Content;
+using Microsoft.Xna.Framework.Input;
+
+using Syntriax.Engine.Core;
+using Syntriax.Engine.Core.Debug;
+using Syntriax.Engine.Core.Exceptions;
+using Syntriax.Engine.Integration.MonoGame;
+using Syntriax.Engine.Network;
+using Syntriax.Engine.Systems.Input;
+using Syntriax.Engine.Systems.Time;
+using Syntriax.Engine.Systems.Tween;
+
+namespace Pong.Behaviours;
+
+public class PongGameStarter : Behaviour, INetworkEntity, IFirstFrameUpdate,
+    IPacketListenerServer<PongGameStarter.RequestStartPacket>,
+    IPacketListenerClient<PongGameStarter.RequestStartPacket>
+{
+    private const float START_COUNTDOWN = 3f;
+
+    private INetworkCommunicatorServer? networkServer = null;
+    private INetworkCommunicatorClient? networkClient = null;
+    private ITweenManager? tweenManager = null;
+    private PongManager pongManager = null!;
+
+    private ILogger? logger = null;
+
+    private Label? label = null;
+    private TickerTimer timer = null!;
+
+    public void FirstActiveFrame()
+    {
+        IButtonInputs<Keys>? buttonInputs = Universe.FindBehaviour<IButtonInputs<Keys>>();
+        buttonInputs?.RegisterOnRelease(Keys.Space, (_, _1) => networkClient?.SendToServer(new RequestStartPacket()));
+
+        networkClient = Universe.FindBehaviour<INetworkCommunicatorClient>();
+        networkServer = Universe.FindBehaviour<INetworkCommunicatorServer>();
+        tweenManager = Universe.FindBehaviour<ITweenManager>();
+        pongManager = BehaviourController.GetRequiredBehaviourInParent<PongManager>();
+        label = BehaviourController.GetRequiredBehaviour<Label>();
+        logger = Universe.FindBehaviour<ILogger>();
+
+        if (!BehaviourController.TryGetBehaviour(out timer!))
+        {
+            timer = BehaviourController.AddBehaviour<TickerTimer>();
+            timer.OnStarted.AddListener(OnCountdownStart);
+            timer.OnTick.AddListener(DisplayCountdown);
+            timer.OnStopped.AddListener(StartPong);
+        }
+    }
+
+    private void OnCountdownStart(IReadOnlyTimer sender)
+    {
+        pongManager.Reset();
+        DisplayCountdown(timer);
+    }
+
+    private void DisplayCountdown(ITicker sender)
+    {
+        if (label != null)
+        {
+            label.Text = $"{START_COUNTDOWN - timer.TickCounter}";
+            label.Color = new ColorRGBA(255, 255, 255, 255);
+            if (tweenManager is not null)
+                label.Color.TweenColor(tweenManager, 1f, new ColorRGBA(255, 255, 255, 0), (x) => label.Color = x);
+        }
+    }
+
+    private void StartPong(IReadOnlyTimer sender)
+    {
+        pongManager.Start();
+    }
+
+    void IPacketListenerServer<RequestStartPacket>.OnServerPacketArrived(IConnection sender, RequestStartPacket packet)
+    {
+        logger?.Log(this, $"{sender} requested start");
+
+        if (pongManager.IsGameInProgress)
+        {
+            logger?.Log(this, $"The game is already in progress");
+            return;
+        }
+
+        timer.Start(START_COUNTDOWN);
+        networkServer?.SendToAll(packet);
+    }
+
+    void IPacketListenerClient<RequestStartPacket>.OnClientPacketArrived(IConnection sender, RequestStartPacket packet)
+    {
+        logger?.Log(this, $"Server is starting the game");
+        timer.Start(START_COUNTDOWN - sender.Ping);
+    }
+
+    private class RequestStartPacket : INetworkPacket;
+}
diff --git a/Shared/Behaviours/PongManager.cs b/Shared/Behaviours/PongManager.cs
index d1646de..e8164fe 100644
--- a/Shared/Behaviours/PongManager.cs
+++ b/Shared/Behaviours/PongManager.cs
@@ -1,16 +1,12 @@
 using System;
 
-using Microsoft.Xna.Framework.Input;
-
 using Syntriax.Engine.Core;
 using Syntriax.Engine.Core.Debug;
 using Syntriax.Engine.Network;
-using Syntriax.Engine.Systems.Input;
 
 namespace Pong.Behaviours;
 
 public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
-    IPacketListenerServer<PongManager.RequestStartPacket>,
     IPacketListenerClient<PongManager.ScorePacket>
 {
     public Action<PongManager>? OnReset { get; set; } = null;
@@ -18,9 +14,7 @@ public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
     public Action<PongManager>? OnScoreUpdated { get; set; } = null;
 
     private Random random = new();
-    private Ball ball = null!;
 
-    private INetworkCommunicatorClient? networkClient = null!;
     private INetworkCommunicatorServer? networkServer = null;
     private ILogger? logger = null;
 
@@ -29,17 +23,16 @@ public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
     public int ScoreSum => ScoreLeft + ScoreRight;
 
     public int WinScore { get; } = 5;
+    public Ball Ball { get; private set; } = null!;
+
+    public bool IsGameInProgress { get; private set; } = false;
 
     public PongManager() => WinScore = 5;
     public PongManager(int winScore) => WinScore = winScore;
 
     public void FirstActiveFrame()
     {
-        IButtonInputs<Keys>? buttonInputs = Universe.FindBehaviour<IButtonInputs<Keys>>();
-        buttonInputs?.RegisterOnRelease(Keys.Space, (_, _1) => networkClient?.SendToServer(new RequestStartPacket()));
-
-        ball = Universe.FindRequiredBehaviour<Ball>();
-        networkClient = Universe.FindBehaviour<INetworkCommunicatorClient>();
+        Ball = Universe.FindRequiredBehaviour<Ball>();
         networkServer = Universe.FindBehaviour<INetworkCommunicatorServer>();
         logger = Universe.FindBehaviour<ILogger>();
     }
@@ -60,18 +53,34 @@ public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
         PostScoreUpdate();
     }
 
+    public bool Start()
+    {
+        if (networkServer is null)
+            return false;
+
+        if (Ball.RigidBody.Velocity.MagnitudeSquared > 0.01f)
+            return false;
+
+        Reset();
+        IsGameInProgress = true;
+        PostScoreUpdate();
+        logger?.Log(this, $"Game started");
+        return true;
+    }
+
     public void Reset()
     {
         ScoreLeft = ScoreRight = 0;
+        IsGameInProgress = false;
 
-        PostScoreUpdate();
+        Ball.ResetBall();
 
         OnReset?.Invoke(this);
     }
 
     private void PostScoreUpdate()
     {
-        ball.ResetBall();
+        Ball.ResetBall();
 
         if (networkServer is not null)
         {
@@ -82,12 +91,13 @@ public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
         int halfwayScore = (int)(WinScore * .5f);
         if (ScoreLeft > halfwayScore || ScoreRight > halfwayScore)
         {
+            IsGameInProgress = false;
             OnFinished?.Invoke(this);
             logger?.Log(this, $"Game finished");
             return;
         }
 
-        ball.LaunchBall(GetBallLaunchDirection());
+        Ball.LaunchBall(GetBallLaunchDirection());
     }
 
     private Vector2D GetBallLaunchDirection()
@@ -107,18 +117,6 @@ public class PongManager : Behaviour, INetworkEntity, IFirstFrameUpdate,
         logger?.Log(this, $"Client score update packet arrived: {packet.Left} - {packet.Right}");
     }
 
-    void IPacketListenerServer<RequestStartPacket>.OnServerPacketArrived(IConnection sender, RequestStartPacket packet)
-    {
-        logger?.Log(this, $"{sender} requested start");
-        if (ball.RigidBody.Velocity.MagnitudeSquared > 0.01f)
-            return;
-
-        Reset();
-        ball.LaunchBall(GetBallLaunchDirection());
-        logger?.Log(this, $"Game started");
-    }
-
-    private class RequestStartPacket : INetworkPacket;
     private class ScorePacket : INetworkPacket
     {
         public int Left { get; set; }
diff --git a/Shared/PongUniverse.cs b/Shared/PongUniverse.cs
index f29c8a7..6c4ed5c 100644
--- a/Shared/PongUniverse.cs
+++ b/Shared/PongUniverse.cs
@@ -66,6 +66,11 @@ public static class PongUniverse
         PongManager pongManager = universe.InstantiateUniverseObject().SetUniverseObject("Pong Game Manager")
             .BehaviourController.AddBehaviour<PongManager>(5);
 
+        universe.InstantiateUniverseObject().SetUniverseObject("Pong Game Starter", parent: pongManager.UniverseObject)
+            .BehaviourController.AddBehaviour<PongGameStarter>()
+            .BehaviourController.AddBehaviour<Transform2D>().SetTransform(position: new Vector2D(-24, 250f), scale: Vector2D.One * .5f)
+            .BehaviourController.AddBehaviour<Label>();
+
         ////////////////////////////////////////////////////////////////////////////////////
 
         universe.InstantiateUniverseObject().SetUniverseObject("Ball")