fix: synced timer

app/src/main/java/game/Game.java

@@ -1,5 +1,6 @@
 package game;
 
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -14,10 +15,13 @@ public class Game {
 		GameNotStarted, GameGoing, GameEnd
 	}
 
+	public static final int GAME_DURATION = 10 * 60;
+
 	private final Map<Integer, Player> players;
 	private final List<Player> leaderboard;
 	private GameState gameState;
 	private MultiDoku doku;
+	private Instant startTime = null;
 
 	public Game() {
 		this.players = new HashMap<>();
@@ -49,9 +53,10 @@ public class Game {
 		return players;
 	}
 
-	public void startGame(MultiDoku doku) {
+	public void startGame(MultiDoku doku, Instant startTime) {
 		this.doku = doku;
 		this.gameState = GameState.GameGoing;
+		this.startTime = startTime;
 	}
 
 	public GameState getGameState() {
@@ -66,4 +71,8 @@ public class Game {
 		return leaderboard;
 	}
 
+	public Instant getStartTime() {
+		return startTime;
+	}
+
 }

app/src/main/java/gui/menu/MultiPlayerDokuView.java

@@ -1,5 +1,6 @@
 package gui.menu;
 
+import game.Game;
 import gui.widget.LeaderboardRenderer;
 import gui.widget.SudokuRenderer;
 import gui.widget.TimerRenderer;
@@ -15,7 +16,6 @@ public class MultiPlayerDokuView extends BaseView{
 	private final SudokuRenderer sudokuRenderer;
 	private final LeaderboardRenderer leaderboardRenderer;
 	private final TimerRenderer timerRenderer;
-	private static final float GAME_DURATION = 10 * 60;
 
 	public MultiPlayerDokuView(StateMachine stateMachine, Client client, Server server) {
 		super(stateMachine);
@@ -25,8 +25,7 @@ public class MultiPlayerDokuView extends BaseView{
 		this.leaderboardRenderer = new LeaderboardRenderer(client.getGame(), client.getPlayer());
 		this.sudokuRenderer.onCellChange.connect(this::onCellChange);
 		this.client.onDisconnect.connect(this::onDisconnect);
-		// TODO: sync timer
+		this.timerRenderer = new TimerRenderer(this.client.getGame().getStartTime(), Game.GAME_DURATION);
-		this.timerRenderer = new TimerRenderer(GAME_DURATION);
 	}
 
 	private void onCellChange(Cell cell) {

app/src/main/java/gui/widget/TimerRenderer.java

@@ -1,24 +1,26 @@
 package gui.widget;
 
+import java.time.Instant;
+
 import imgui.ImGui;
 
 public class TimerRenderer {
 
-	private float time;
+	private final long endTime;
-	private final float duration;
 
-	public TimerRenderer(float duration) {
+	public TimerRenderer(Instant startTime, int duration) {
-		this.time = 0;
+		this.endTime = startTime.getEpochSecond() + duration;
-		this.duration = duration;
+	}
+
+	private long getTimeRemaining() {
+		long currentTime = Instant.now().getEpochSecond();
+		return endTime - currentTime;
 	}
 
 	public void render() {
-		this.time += ImGui.getIO().getDeltaTime();
+		long seconds = getTimeRemaining();
-		float remainingTime = this.duration - this.time;
+		long minutes = seconds / 60;
-		int seconds = (int) remainingTime;
+		String text = String.format("%02d:%02d", minutes, seconds % 60);
-		int minutes = seconds / 60;
-		seconds %= 60;
-		String text = String.format("%02d:%02d", minutes, seconds);
 		var textSize = ImGui.calcTextSize(text);
 		ImGui.setCursorPosX(ImGui.getIO().getDisplaySizeX() / 2.0f - textSize.x / 2.0f);
 		ImGui.text(text);

app/src/main/java/network/client/ClientConnexion.java

@@ -71,7 +71,8 @@ public class ClientConnexion extends Connexion {
 
 	@Override
 	public void visitPacket(StartGamePacket packet) {
-		this.client.getGame().startGame(SudokuSerializer.deserializeSudoku(packet.getSerializedSudoku()));
+		this.client.getGame().startGame(SudokuSerializer.deserializeSudoku(packet.getSerializedSudoku()),
+				packet.getInstant());
 		this.client.onGameStarted.emit();
 	}
 

app/src/main/java/network/protocol/packets/StartGamePacket.java

@@ -1,5 +1,7 @@
 package network.protocol.packets;
 
+import java.time.Instant;
+
 import network.protocol.Packet;
 import network.protocol.PacketVisitor;
 import network.protocol.Packets;
@@ -9,15 +11,22 @@ public class StartGamePacket extends Packet {
 	static private final long serialVersionUID = Packets.StartGame.ordinal();
 
 	private final String serializedSudoku;
+	// used to resume game
+	private final Instant instant;
 
-	public StartGamePacket(String serializedSudoku) {
+	public StartGamePacket(String serializedSudoku, Instant instant) {
 		this.serializedSudoku = serializedSudoku;
+		this.instant = instant;
 	}
 
 	public String getSerializedSudoku() {
 		return serializedSudoku;
 	}
 
+	public Instant getInstant() {
+		return instant;
+	}
+
 	@Override
 	public void accept(PacketVisitor packetVisitor) {
 		packetVisitor.visitPacket(this);

app/src/main/java/network/server/Server.java

@@ -2,6 +2,7 @@ package network.server;
 
 import java.io.IOException;
 import java.net.ServerSocket;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -69,11 +70,12 @@ public class Server {
 	}
 
 	public void startGame(MultiDoku doku) {
-		this.game.startGame(doku);
+		Instant now = Instant.now();
+		this.game.startGame(doku, now);
 		for (ServerConnexion connexion : this.connexions) {
 			connexion.setSudoku(doku.clone());
 		}
-		broadcastPacket(new StartGamePacket(SudokuSerializer.serializeSudoku(doku).toString()));
+		broadcastPacket(new StartGamePacket(SudokuSerializer.serializeSudoku(doku).toString(), now));
 	}
 
 }

app/src/main/java/network/server/ServerConnexion.java

@@ -3,6 +3,7 @@ package network.server;
 import java.io.IOException;
 import java.net.Socket;
 
+import game.Game;
 import game.Player;
 import game.Game.GameState;
 import network.Connexion;
@@ -69,10 +70,13 @@ public class ServerConnexion extends Connexion {
 		this.server.broadcastPacket(new PlayerJoinPacket(player));
 		sendPacket(new ConnexionInfoPacket(player.getId()));
 
-		if (this.server.getGame().getGameState() == GameState.GameGoing) {
+		Game game = this.server.getGame();
-			setSudoku(this.server.getGame().getDoku().clone());
+
+		if (game.getGameState() == GameState.GameGoing) {
+			setSudoku(game.getDoku().clone());
 			sendPacket(
-					new StartGamePacket(SudokuSerializer.serializeSudoku(this.server.getGame().getDoku()).toString()));
+					new StartGamePacket(SudokuSerializer.serializeSudoku(game.getDoku()).toString(),
+							game.getStartTime()));
 		}
 	}