big merge je vais dcd

# Conflicts:
#	app/src/main/java/sudoku/Main.java
#	app/src/main/java/sudoku/solver/Solver.java

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4

.gitignore

@@ -7,4 +7,6 @@ build
 .vscode
 .idea
 
-output.puml
+output.puml
+
+imgui.ini

README.md

@@ -0,0 +1,21 @@
+# Sudoku 🧩
+
+## Features 🌟
+
+- Graphical User Interface (GUI)
+- Sudoku saves
+- Multiplayer
+
+## Develop ☝🤓
+
+### Run 🏃
+
+```sh
+./gradlew run
+```
+
+### Run tests 🗣️🔥
+
+```sh
+./gradlew test
+```

app/build.gradle

@@ -11,9 +11,14 @@ plugins {
     id 'application'
 }
 
+project.ext.os = System.properties['os.name'].toLowerCase().split(" ")[0]
+
 repositories {
     // Use Maven Central for resolving dependencies.
     mavenCentral()
+    flatDir {
+       dirs("$rootProject.projectDir/libs")
+   }
 }
 
 dependencies {
@@ -25,14 +30,28 @@ dependencies {
 
     // uml
     implementation 'com.github.javaparser:javaparser-symbol-solver-core:3.26.2'
+
+    implementation 'org.json:json:20250107'
+
+    implementation 'com.fasterxml.jackson.core:jackson-databind:2.18.2'
+
+    implementation "io.github.spair:imgui-java-app:1.88.0"
+
+    implementation "org.lwjgl:lwjgl-stb:3.3.4"
+
+    runtimeOnly "org.lwjgl:lwjgl-stb::natives-$os"
 }
 
 application {
     // Define the main class for the application.
-    mainClass = 'sudoku.Main'
+    mainClass = 'gui.Main'
 }
 
 tasks.named('test') {
     // Use JUnit Platform for unit tests.
     useJUnitPlatform()
 }
+
+run {
+    enableAssertions = true
+}

app/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

app/save/save-1.json

@@ -0,0 +1,572 @@
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+         40,
+         41,
+         48,
+         49,
+         50
+      ]},
+      {"cellIDs": [
+         33,
+         34,
+         35,
+         42,
+         43,
+         44,
+         51,
+         52,
+         53
+      ]},
+      {"cellIDs": [
+         54,
+         55,
+         56,
+         63,
+         64,
+         65,
+         72,
+         73,
+         74
+      ]},
+      {"cellIDs": [
+         57,
+         58,
+         59,
+         66,
+         67,
+         68,
+         75,
+         76,
+         77
+      ]},
+      {"cellIDs": [
+         60,
+         61,
+         62,
+         69,
+         70,
+         71,
+         78,
+         79,
+         80
+      ]}
+   ],
+   "multidoku": [{
+      "blockWidth": 3,
+      "cells": [
+         0,
+         1,
+         2,
+         3,
+         4,
+         5,
+         6,
+         7,
+         8,
+         9,
+         10,
+         11,
+         12,
+         13,
+         14,
+         15,
+         16,
+         17,
+         18,
+         19,
+         20,
+         21,
+         22,
+         23,
+         24,
+         25,
+         26,
+         27,
+         28,
+         29,
+         30,
+         31,
+         32,
+         33,
+         34,
+         35,
+         36,
+         37,
+         38,
+         39,
+         40,
+         41,
+         42,
+         43,
+         44,
+         45,
+         46,
+         47,
+         48,
+         49,
+         50,
+         51,
+         52,
+         53,
+         54,
+         55,
+         56,
+         57,
+         58,
+         59,
+         60,
+         61,
+         62,
+         63,
+         64,
+         65,
+         66,
+         67,
+         68,
+         69,
+         70,
+         71,
+         72,
+         73,
+         74,
+         75,
+         76,
+         77,
+         78,
+         79,
+         80
+      ],
+      "blocks": [
+         0,
+         1,
+         2,
+         3,
+         4,
+         5,
+         6,
+         7,
+         8
+      ],
+      "constraints": [
+         0,
+         1,
+         2
+      ]
+   }]
+}

app/src/main/java/common/Signal.java

@@ -0,0 +1,31 @@
+package common;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class Signal {
+
+	private final Set<Runnable> listeners;
+
+	public Signal() {
+		this.listeners = new HashSet<>();
+	}
+
+	public void connect(Runnable listener) {
+		this.listeners.add(listener);
+	}
+
+	public void clear() {
+		this.listeners.clear();
+	}
+
+	public void emit() {
+		for (Runnable listener : this.listeners) {
+			listener.run();
+		}
+	}
+	
+	// public void disconnect(Runnable listener) {
+	// 	this.listeners.remove(listener);
+	// }
+}

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

@@ -0,0 +1,52 @@
+package game;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import sudoku.structure.MultiDoku;
+
+public class Game {
+
+	public static enum GameState {
+		GameNotStarted, GameGoing, GameEnd
+	}
+
+	private final Map<Integer, Player> players;
+	private GameState gameState;
+	private MultiDoku doku;
+
+	public Game() {
+		this.players = new HashMap<>();
+		this.gameState = GameState.GameNotStarted;
+	}
+
+	public Player getPlayerById(int id) {
+		return players.get(id);
+	}
+
+	public void addPlayer(Player player) {
+		players.put(player.getId(), player);
+	}
+
+	public void removePlayer(int id) {
+		players.remove(id);
+	}
+
+	public Map<Integer, Player> getPlayers() {
+		return players;
+	}
+
+	public void startGame(MultiDoku doku) {
+		this.doku = doku;
+		this.gameState = GameState.GameGoing;
+	}
+
+	public GameState getGameState() {
+		return gameState;
+	}
+
+	public MultiDoku getDoku() {
+		return doku;
+	}
+
+}

app/src/main/java/game/Player.java

@@ -0,0 +1,25 @@
+package game;
+
+import java.io.Serializable;
+
+public class Player implements Serializable {
+
+	static private final long serialVersionUID = 9999;
+
+	private final String pseudo;
+	private final int id;
+
+	public Player(int id, String pseudo) {
+		this.pseudo = pseudo;
+		this.id = id;
+	}
+
+	public String getPseudo() {
+		return this.pseudo;
+	}
+
+	public int getId() {
+		return this.id;
+	}
+
+}

app/src/main/java/gui/ColorGenerator.java

@@ -0,0 +1,70 @@
+package gui;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class ColorGenerator {
+
+	public static class Color {
+		public float r, g, b;
+
+		public Color(float r, float g, float b) {
+			this.r = r;
+			this.g = g;
+			this.b = b;
+		}
+
+	}
+
+	public static List<Color> greatPalette(int colorCount) {
+		List<Color> colors = greatScheme(colorCount);
+		List<Color> newOrder = new ArrayList<>();
+		int newIndex = 0;
+		while (!colors.isEmpty()) {
+			int randomIndex = newIndex % colors.size();
+			newOrder.add(colors.get(randomIndex));
+			colors.remove(randomIndex);
+			newIndex += Math.sqrt(colorCount) + 1;
+		}
+		return newOrder;
+	}
+
+	public static List<Color> greatScheme(int colorCount) {
+		List<Color> colors = new ArrayList<>();
+		for (int i = 0; i < colorCount; i++) {
+			colors.add(hslToRgb((float) (i) / (float) colorCount, 0.9f, 0.4f));
+		}
+		return colors;
+	}
+
+	public static Color hslToRgb(float h, float s, float l){
+		float r, g, b;
+	
+		if (s == 0f) {
+			r = g = b = l; // achromatic
+		} else {
+			float q = l < 0.5f ? l * (1 + s) : l + s - l * s;
+			float p = 2 * l - q;
+			r = hueToRgb(p, q, h + 1f/3f);
+			g = hueToRgb(p, q, h);
+			b = hueToRgb(p, q, h - 1f/3f);
+		}
+		return new Color(r, g, b);
+	}
+
+	/** Helper method that converts hue to rgb */
+	public static float hueToRgb(float p, float q, float t) {
+		if (t < 0f)
+			t += 1f;
+		if (t > 1f)
+			t -= 1f;
+		if (t < 1f / 6f)
+			return p + (q - p) * 6f * t;
+		if (t < 1f / 2f)
+			return q;
+		if (t < 2f / 3f)
+			return p + (q - p) * (2f / 3f - t) * 6f;
+		return p;
+	}
+
+}

app/src/main/java/gui/Fonts.java

@@ -0,0 +1,34 @@
+package gui;
+
+import imgui.ImFont;
+import imgui.ImFontConfig;
+import imgui.ImFontGlyphRangesBuilder;
+import imgui.ImGui;
+
+public class Fonts {
+
+	public static ImFont ARIAL;
+	public static ImFont ARIAL_BOLD;
+	public static ImFont CHERI;
+	public static ImFont COMIC;
+	public static ImFont INFECTED;
+	public static ImFont EMOJIS;
+
+	private static final String baseDir = "";
+
+	public static void createFonts() {
+		ImFontGlyphRangesBuilder builder = new ImFontGlyphRangesBuilder();
+		builder.addRanges(ImGui.getIO().getFonts().getGlyphRangesDefault());
+		builder.addRanges(ImGui.getIO().getFonts().getGlyphRangesCyrillic());
+		// builder.addRanges(ImGui.getIO().getFonts().getGlyphRangesChineseFull());
+		ImFontConfig cfg = new ImFontConfig();
+		cfg.setGlyphRanges(builder.buildRanges());
+
+		COMIC = ImGui.getIO().getFonts().addFontFromFileTTF(baseDir + "comic.ttf", 50.0f);
+		ARIAL_BOLD = ImGui.getIO().getFonts().addFontFromFileTTF(baseDir + "arial_bold.ttf", 50.0f);
+		ARIAL = ImGui.getIO().getFonts().addFontFromFileTTF(baseDir + "arial.ttf", 50.0f, cfg);
+		CHERI = ImGui.getIO().getFonts().addFontFromFileTTF(baseDir + "cheri.ttf", 50.0f);
+		INFECTED = ImGui.getIO().getFonts().addFontFromFileTTF(baseDir + "INFECTED.ttf", 50.0f);
+	}
+
+}

app/src/main/java/gui/Images.java

@@ -0,0 +1,39 @@
+package gui;
+
+import java.nio.ByteBuffer;
+
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.stb.STBImage;
+
+public class Images {
+
+	public static int BACKGROUND;
+
+	private static int loadTexture(String fileName) {
+		int[] width = new int[1];
+		int[] height = new int[1];
+		int[] channelCount = new int[1];
+
+		ByteBuffer pixels = STBImage.stbi_load(fileName, width, height, channelCount, 4);
+
+		int textureID = GL11.glGenTextures();
+		GL11.glBindTexture(GL11.GL_TEXTURE_2D, textureID);
+		GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER, GL11.GL_LINEAR);
+		GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER, GL11.GL_LINEAR);
+		GL11.glPixelStorei(GL11.GL_UNPACK_ALIGNMENT, 1); // Not on WebGL/ES
+		GL11.glPixelStorei(GL11.GL_UNPACK_SKIP_PIXELS, 0); // Not on WebGL/ES
+		GL11.glPixelStorei(GL11.GL_UNPACK_SKIP_ROWS, 0); // Not on WebGL/ES
+		GL11.glPixelStorei(GL11.GL_UNPACK_ROW_LENGTH, 0); // Not on WebGL/ES
+		GL11.glTexImage2D(GL11.GL_TEXTURE_2D, 0, GL11.GL_RGBA, width[0], height[0], 0,
+				GL11.GL_RGBA,
+				GL11.GL_UNSIGNED_BYTE, pixels);
+		GL11.glBindTexture(GL11.GL_TEXTURE_2D, 0);
+
+		return textureID;
+	}
+
+	public static void loadImages() {
+		BACKGROUND = loadTexture("background.png");
+	}
+
+}

app/src/main/java/gui/Main.java

@@ -0,0 +1,45 @@
+package gui;
+
+import gui.menu.MainMenu;
+import gui.menu.StateMachine;
+import imgui.ImGui;
+import imgui.app.Application;
+import imgui.app.Configuration;
+
+public class Main extends Application {
+
+    private final StateMachine stateMachine = new StateMachine();
+
+    @Override
+    protected void configure(Configuration config) {
+        config.setTitle("Let's play sudoku!");
+    }
+
+    @Override
+    protected void disposeWindow() {
+        stateMachine.clear();
+    }
+
+    @Override
+    protected void initImGui(Configuration config) {
+        super.initImGui(config);
+        Fonts.createFonts();
+        stateMachine.pushState(new MainMenu(stateMachine));
+    }
+    
+    @Override
+    protected void preRun() {
+        super.preRun();
+        Images.loadImages();
+    }
+
+    @Override
+    public void process() {
+        stateMachine.render();
+        // ImGui.showDemoWindow();
+    }
+
+    public static void main(String[] args) {
+        launch(new Main());
+    }
+}

app/src/main/java/gui/Options.java

@@ -0,0 +1,7 @@
+package gui;
+
+public class Options {
+
+	public static Symbols Symboles = Symbols.Numbers;
+
+}

app/src/main/java/gui/RenderableMultidoku.java

@@ -0,0 +1,195 @@
+package gui;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import sudoku.structure.Block;
+import sudoku.structure.Cell;
+import sudoku.structure.Coordinate;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class RenderableMultidoku {
+
+	private final MultiDoku doku;
+	private final List<Cell> cells;
+	private final List<Block> blocks;
+	private final int width;
+	private final int height;
+
+	private RenderableMultidoku(MultiDoku doku, List<Block> blocks, List<Cell> cells, int width, int height) {
+		this.cells = cells;
+		this.blocks = blocks;
+		this.width = width;
+		this.height = height;
+		this.doku = doku;
+	}
+
+	public int getWidth() {
+		return width;
+	}
+
+	public int getHeight() {
+		return height;
+	}
+
+	public List<Block> getBlocks() {
+		return this.blocks;
+	}
+
+	public Cell getCell(int x, int y) {
+		return getCell(y * width + x);
+	}
+
+	public Cell getCell(int index) {
+		return cells.get(index);
+	}
+
+	private static record PositionConstraint(Sudoku sudoku1, Sudoku sudoku2, Coordinate offset) {
+	}
+
+	private static Coordinate getConstraint(Sudoku sudoku1, Sudoku sudoku2) {
+		int blockWidth = sudoku1.getBlockWidth();
+		int blockHeight = sudoku1.getSize() / blockWidth;
+		for (int i = 0; i < sudoku1.getSize(); i++) {
+			for (int j = 0; j < sudoku2.getSize(); j++) {
+				Block block1 = sudoku1.getBlocks().get(i);
+				Block block2 = sudoku2.getBlocks().get(j);
+				if (block1 == block2) {
+					int block1X = i % blockHeight;
+					int block1Y = i / blockHeight;
+					int block2X = j % blockHeight;
+					int block2Y = j / blockHeight;
+					return new Coordinate((block1X - block2X) * blockWidth, (block1Y - block2Y) * blockHeight);
+				}
+			}
+		}
+		return null;
+	}
+
+	private static boolean hasContraint(Sudoku sudoku1, Sudoku sudoku2, List<PositionConstraint> positionConstraints) {
+		for (PositionConstraint constraint : positionConstraints) {
+			if ((constraint.sudoku1 == sudoku1 && constraint.sudoku2 == sudoku2)
+					|| (constraint.sudoku1 == sudoku2 && constraint.sudoku2 == sudoku1))
+				return true;
+		}
+		return false;
+	}
+
+	private static Coordinate getMinSudokuOffset(Map<Sudoku, Coordinate> sudokusOffset) {
+		Coordinate minCoordinate = null;
+		for (Coordinate coordinate : sudokusOffset.values()) {
+			if (minCoordinate == null)
+				minCoordinate = coordinate;
+			minCoordinate = new Coordinate(Math.min(minCoordinate.getX(), coordinate.getX()),
+					Math.min(minCoordinate.getY(), coordinate.getY()));
+		}
+		return minCoordinate;
+	}
+
+	private static Coordinate getMaxSudokuCoordinate(Map<Sudoku, Coordinate> sudokusOffset) {
+		Coordinate maxCoordinate = null;
+		Sudoku maxSudoku = null;
+		float maxDistanceSquared = 0;
+		for (var entry : sudokusOffset.entrySet()) {
+			Coordinate coordinate = entry.getValue();
+			float distanceSquared = coordinate.getX() * coordinate.getX() + coordinate.getY() * coordinate.getY();
+			if (maxCoordinate == null) {
+				maxCoordinate = coordinate;
+				maxDistanceSquared = distanceSquared;
+				maxSudoku = entry.getKey();
+			}
+
+			if (distanceSquared > maxDistanceSquared) {
+				maxDistanceSquared = distanceSquared;
+				maxSudoku = entry.getKey();
+				maxCoordinate = coordinate;
+			}
+		}
+
+		int blockWidth = maxSudoku.getBlockWidth();
+		int blockHeight = maxSudoku.getSize() / blockWidth;
+
+		return new Coordinate(maxCoordinate.getX() + maxSudoku.getSize(), maxCoordinate.getY() + maxSudoku.getSize());
+	}
+
+	public static RenderableMultidoku fromMultidoku(MultiDoku doku) {
+		if (doku.getNbSubGrids() == 1) {
+			Sudoku sudoku = doku.getSubGrid(0);
+			return new RenderableMultidoku(doku, sudoku.getBlocks(), sudoku.getCells(), sudoku.getSize(),
+					sudoku.getSize());
+		}
+		Map<Sudoku, Coordinate> sudokusOffset = new HashMap<>();
+		// coordinates in cell
+		List<PositionConstraint> positionConstraints = new ArrayList<>();
+		for (Sudoku sudoku1 : doku.getSubGrids()) {
+			for (Sudoku sudoku2 : doku.getSubGrids()) {
+				if (sudoku1 == sudoku2)
+					continue;
+
+				Coordinate constraint = getConstraint(sudoku1, sudoku2);
+
+				if (constraint != null && !hasContraint(sudoku1, sudoku2, positionConstraints)) {
+					positionConstraints.add(new PositionConstraint(sudoku1, sudoku2, constraint));
+				}
+			}
+		}
+
+		for (PositionConstraint constraint : positionConstraints) {
+			if (!sudokusOffset.containsKey(constraint.sudoku1) && !sudokusOffset.containsKey(constraint.sudoku2)) {
+				sudokusOffset.put(constraint.sudoku1, new Coordinate(0, 0));
+				sudokusOffset.put(constraint.sudoku2, constraint.offset());
+			}
+
+			if (sudokusOffset.containsKey(constraint.sudoku1)) {
+				sudokusOffset.put(constraint.sudoku2, constraint.offset.add(sudokusOffset.get(constraint.sudoku1)));
+			} else {
+				sudokusOffset.put(constraint.sudoku1, constraint.offset.add(sudokusOffset.get(constraint.sudoku2)));
+			}
+
+		}
+
+		Coordinate minCoordinate = getMinSudokuOffset(sudokusOffset);
+
+		for (var entry : sudokusOffset.entrySet()) {
+			entry.setValue(entry.getValue().sub(minCoordinate));
+		}
+
+		Coordinate maxCoordinate = getMaxSudokuCoordinate(sudokusOffset);
+
+		List<Block> blocks = new ArrayList<>();
+		List<Cell> cells = new ArrayList<>(maxCoordinate.getX() * maxCoordinate.getY());
+		for (int i = 0; i < maxCoordinate.getX() * maxCoordinate.getY(); i++) {
+			cells.add(null);
+		}
+
+		for (var entry : sudokusOffset.entrySet()) {
+			Sudoku sudoku = entry.getKey();
+			Coordinate offset = entry.getValue();
+
+			for (int x = 0; x < sudoku.getSize(); x++) {
+				for (int y = 0; y < sudoku.getSize(); y++) {
+					Cell cell = sudoku.getCell(x, y);
+					int absoluteX = x + offset.getX();
+					int absoluteY = y + offset.getY();
+					cells.set(absoluteY * maxCoordinate.getX() + absoluteX, cell);
+				}
+			}
+
+			for (Block block : sudoku.getBlocks()) {
+				if (!blocks.contains(block)) {
+					blocks.add(block);
+				}
+			}
+		}
+
+		return new RenderableMultidoku(doku, blocks, cells, maxCoordinate.getX(), maxCoordinate.getY());
+	}
+
+	public MultiDoku getDoku() {
+		return doku;
+	}
+
+}

app/src/main/java/gui/SudokuRenderer.java

@@ -0,0 +1,146 @@
+package gui;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import common.Signal;
+import gui.ColorGenerator.Color;
+import imgui.ImGui;
+import imgui.ImVec2;
+import imgui.ImVec4;
+import imgui.flag.ImGuiCol;
+import imgui.flag.ImGuiStyleVar;
+import sudoku.constraint.Constraint;
+import sudoku.structure.Block;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class SudokuRenderer {
+
+	private final RenderableMultidoku doku;
+	private Cell currentCell = null;
+	private final Map<Block, Color> colorPalette;
+
+	private static final ImVec4 BLACK = new ImVec4(0, 0, 0, 1);
+	private static final ImVec4 TRANSPARENT = new ImVec4();
+	private static final ImVec4 WHITE = new ImVec4(1.0f, 1.0f, 1.0f, 1.0f);
+	private static final ImVec2 cellSize = new ImVec2(50, 50);
+
+	private final Set<Cell> diagonals = new HashSet<>();
+
+	public final Signal onResolve = new Signal();
+
+	public SudokuRenderer(MultiDoku doku) {
+		this.doku = RenderableMultidoku.fromMultidoku(doku);
+		this.colorPalette = initColors();
+		initDiagonals();
+	}
+
+	private void initDiagonals() {
+		for (Sudoku sudoku : this.doku.getDoku().getSubGrids()) {
+			if (sudoku.hasConstraint(Constraint.Diagonal)) {
+				for (int i = 0; i < sudoku.getSize(); i++) {
+					this.diagonals.add(sudoku.getCell(i, i));
+					this.diagonals.add(sudoku.getCell(sudoku.getSize() - i - 1, i));
+				}
+			}
+		}
+	}
+
+	private Map<Block, Color> initColors() {
+		List<Color> colors = ColorGenerator.greatPalette(doku.getBlocks().size());
+		Map<Block, Color> colorPalette = new HashMap<>();
+		int index = 0;
+		for (Block block : doku.getBlocks()) {
+			colorPalette.put(block, colors.get(index));
+			index++;
+		}
+		return colorPalette;
+	}
+
+	private void renderPopup() {
+		if (ImGui.beginPopup("editPopup")) {
+			Block block = currentCell.getBlock();
+			int symbolCount = block.getCells().size();
+			for (int i = 0; i < symbolCount; i++) {
+				if ((i + 1) % (int) (Math.sqrt(symbolCount)) != 1)
+					ImGui.sameLine();
+				if (currentCell.getSymbolIndex() == i) {
+					if (ImGui.button("X", cellSize)) {
+						currentCell.setSymbolIndex(Cell.NOSYMBOL);
+						ImGui.closeCurrentPopup();
+					}
+				} else {
+					if (ImGui.button(Options.Symboles.getSymbols().get(i), cellSize)) {
+						currentCell.trySetValue(i);
+						if (this.doku.getDoku().isSolved())
+							this.onResolve.emit();
+						ImGui.closeCurrentPopup();
+					}
+				}
+			}
+			ImGui.endPopup();
+		}
+	}
+
+	public void render() {
+		if (Options.Symboles == Symbols.Russian) {
+			ImGui.pushFont(Fonts.ARIAL);
+		}
+		final float sudokuViewWidth = cellSize.x * doku.getWidth();
+		final float displayWidth = ImGui.getIO().getDisplaySizeX();
+		float offsetX = displayWidth / 2.0f - sudokuViewWidth / 2.0f;
+		// if the grid is too big, don't offset it
+		if (offsetX > 0) {
+			ImGui.setCursorPosX(offsetX);
+		}
+		ImGui.beginChild(1, new ImVec2(cellSize.x * doku.getWidth(), cellSize.y * doku.getHeight()));
+
+		ImGui.pushStyleVar(ImGuiStyleVar.FrameBorderSize, 2.0f);
+		ImGui.pushStyleVar(ImGuiStyleVar.ItemSpacing, new ImVec2(0.0f, 0.0f));
+		for (int y = 0; y < doku.getHeight(); y++) {
+			for (int x = 0; x < doku.getWidth(); x++) {
+				if (x > 0)
+					ImGui.sameLine();
+				int index = y * doku.getWidth() + x;
+				Cell cell = doku.getCell(x, y);
+				if (cell == null) {
+					ImGui.pushStyleColor(ImGuiCol.Border, TRANSPARENT);
+					ImGui.pushStyleColor(ImGuiCol.Button, TRANSPARENT);
+					ImGui.button("##" + index, cellSize);
+				} else {
+					if (diagonals.contains(cell)) {
+						ImGui.pushStyleColor(ImGuiCol.Border, WHITE);
+					} else {
+						ImGui.pushStyleColor(ImGuiCol.Border, BLACK);
+					}
+					int symbol = cell.getSymbolIndex();
+					Color blockColor = colorPalette.get(cell.getBlock());
+					if (!cell.isMutable()) {
+						blockColor = new Color(blockColor.r - 0.20f, blockColor.g - 0.20f, blockColor.b - 0.20f);
+					}
+					ImGui.pushStyleColor(ImGuiCol.Button, new ImVec4(blockColor.r, blockColor.g, blockColor.b, 1.0f));
+					String cellText = "";
+					if (symbol != -1)
+						cellText += Options.Symboles.getSymbols().get(symbol);
+					if (ImGui.button(cellText + "##" + index, cellSize) && cell.isMutable()) {
+						ImGui.openPopup("editPopup");
+						currentCell = cell;
+					}
+				}
+				ImGui.popStyleColor(2);
+			}
+		}
+		ImGui.popStyleVar(2);
+		renderPopup();
+		ImGui.endChild();
+		if (Options.Symboles == Symbols.Russian) {
+			ImGui.popFont();
+		}
+	}
+
+}

app/src/main/java/gui/SudokuSelector.java

@@ -0,0 +1,136 @@
+package gui;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import common.Signal;
+import imgui.ImGui;
+import imgui.extension.imguifiledialog.ImGuiFileDialog;
+import imgui.extension.imguifiledialog.flag.ImGuiFileDialogFlags;
+import imgui.type.ImBoolean;
+import imgui.type.ImInt;
+import sudoku.constraint.Constraint;
+import sudoku.structure.Difficulty;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;
+
+public class SudokuSelector {
+
+	public final Signal onSelect = new Signal();
+	private MultiDoku doku;
+
+	private final boolean canGenEmptyGrid;
+
+	private final ImInt sudokuType = new ImInt(0);
+
+	private final ImInt difficulty = new ImInt(Difficulty.Medium.ordinal());
+	private final List<ImBoolean> contraints = new ArrayList<>();
+
+	private static final String[] sudokuTypes = { "Carré", "Rectangle", "Multidoku" };
+	private static final int SQUARE = 0, RECTANGLE = 1, MULTIDOKU = 2;
+
+	private final ImInt sudokuSize = new ImInt(3);
+
+	private final ImInt sudokuWidth = new ImInt(3);
+	private final ImInt sudokuHeight = new ImInt(3);
+
+	public SudokuSelector(boolean canGenEmptyGrid) {
+		this.canGenEmptyGrid = canGenEmptyGrid;
+		initConstraints();
+	}
+
+	private List<Constraint> getConstraints() {
+		List<Constraint> constraints = new ArrayList<>();
+		for (int i = 0; i < this.contraints.size(); i++) {
+			if (this.contraints.get(i).get())
+				constraints.add(Constraint.values()[i]);
+		}
+		return constraints;
+	}
+
+	private void initConstraints() {
+		for (Constraint cons : Constraint.values()) {
+			contraints.add(new ImBoolean(SudokuFactory.DEFAULT_CONSTRAINTS.contains(cons)));
+		}
+	}
+
+	private void selectSudoku(MultiDoku doku, boolean empty) {
+		this.doku = doku;
+		if (!empty) {
+			try {
+				SudokuFactory.fillDoku(doku, Difficulty.values()[difficulty.get()]);
+			} catch (Exception e) {
+				e.printStackTrace();
+			}
+		}
+		this.onSelect.emit();
+	}
+
+	public void renderFileDialog() {
+		if (ImGuiFileDialog.display("browse-sudoku", ImGuiFileDialogFlags.None)) {
+			if (ImGuiFileDialog.isOk()) {
+				var selection = ImGuiFileDialog.getSelection();
+				for (var entry : selection.entrySet()) {
+					try {
+						String filePath = entry.getValue();
+						this.doku = SudokuFactory.fromfile(filePath);
+						if (this.doku != null)
+							this.onSelect.emit();
+					} catch (Exception e) {
+						e.printStackTrace();
+					}
+				}
+			}
+			ImGuiFileDialog.close();
+		}
+	}
+
+	public void render() {
+		ImGui.combo("Difficulté", difficulty, Difficulty.getDifficultyNames());
+		if (ImGui.treeNode("Constraintes")) {
+			for (Constraint cons : Constraint.values()) {
+				ImGui.checkbox(cons.getDisplayName(), contraints.get(cons.ordinal()));
+			}
+			ImGui.treePop();
+		}
+		ImGui.combo("Type de Sudoku", sudokuType, SudokuType.getTypeNames());
+		SudokuType currentType = SudokuType.values()[sudokuType.get()];
+		switch (currentType.getMakerParamCount()) {
+			case 1:
+				ImGui.inputInt("Taille", sudokuSize);
+				if (ImGui.button("Résoudre un sudoku")) {
+					selectSudoku(currentType.createDoku(getConstraints(), sudokuSize.get()), false);
+				}
+				if (canGenEmptyGrid && ImGui.button("Générer une grille vide")) {
+					selectSudoku(currentType.createDoku(getConstraints(), sudokuSize.get()), true);
+				}
+				break;
+
+			case 2:
+				ImGui.inputInt("Largeur", sudokuHeight);
+				ImGui.inputInt("Longueur", sudokuWidth);
+				if (ImGui.button("Résoudre un sudoku")) {
+					selectSudoku(currentType.createDoku(getConstraints(), sudokuWidth.get(), sudokuHeight.get()),
+							false);
+				}
+				if (canGenEmptyGrid && ImGui.button("Générer une grille vide")) {
+					selectSudoku(currentType.createDoku(getConstraints(), sudokuWidth.get(), sudokuHeight.get()), true);
+				}
+				break;
+
+			default:
+				assert (false);
+				break;
+		}
+
+		if (ImGui.button("À partir d'un fichier")) {
+			ImGuiFileDialog.openDialog("browse-sudoku", "Choisissez un fichier", ".json", ".");
+		}
+		renderFileDialog();
+	}
+
+	public MultiDoku getDoku() {
+		return doku;
+	}
+
+}

app/src/main/java/gui/SudokuType.java

@@ -0,0 +1,63 @@
+package gui;
+
+import java.util.List;
+
+import sudoku.constraint.Constraint;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;;
+
+public enum SudokuType {
+
+	Square("Carré", 1,
+			(constraints, params) -> SudokuFactory.createBasicEmptySquareDoku(params[0], constraints)),
+	Rectangle("Rectangle", 2,
+			(constraints, params) -> SudokuFactory.createBasicEmptyRectangleDoku(params[0], params[1], constraints)),
+	RandomBloc("Blocs aléatoires", 1,
+			(constraints, params) -> SudokuFactory.createBasicEmptyRandomBlockDoku(params[0], constraints)),
+	MultiDokuSquare("Multidoku carré (X)", 1,
+			(constraints, params) -> SudokuFactory.createBasicXShapedMultidoku(params[0], constraints)),
+	MultidokuRectangle("Multidoku rectangle (X)", 2,
+			(constraints, params) -> SudokuFactory.createBasicXShapedMultidoku(params[0], params[1], constraints));
+
+	String displayName;
+	SudokuMaker maker;
+	int paramCount;
+
+	private SudokuType(String displayName, int paramCount, SudokuMaker maker) {
+		this.displayName = displayName;
+		this.maker = maker;
+		this.paramCount = paramCount;
+	}
+
+	public String getDisplayName() {
+		return this.displayName;
+	}
+
+	public MultiDoku createDoku(List<Constraint> constraints, int... params) {
+		return maker.makeSudoku(constraints, params);
+	}
+
+	public int getMakerParamCount() {
+		return this.paramCount;
+	}
+
+	@FunctionalInterface
+	private static interface SudokuMaker {
+		MultiDoku makeSudoku(List<Constraint> constraints, int... params);
+	}
+
+	private static final String[] dokuNames;
+
+	static {
+		SudokuType[] types = SudokuType.values();
+		dokuNames = new String[types.length];
+		for (int i = 0; i < types.length; i++) {
+			dokuNames[i] = types[i].getDisplayName();
+		}
+	}
+
+	public static String[] getTypeNames() {
+		return dokuNames;
+	}
+
+}

app/src/main/java/gui/Symbols.java

@@ -0,0 +1,83 @@
+package gui;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public enum Symbols {
+
+	Numbers("Nombres", getNumbers()),
+	Letters("Lettres", getLetters()),
+	Russian("Cyrilique", getRussian()),
+	Emojis("Emojis (Console uniquement)", getEmojis());
+
+	String displayName;
+	List<String> symbols;
+
+	private Symbols(String displayName, List<String> symbols) {
+		this.symbols = symbols;
+		this.displayName = displayName;
+	}
+
+	public String getDisplayName() {
+		return displayName;
+	}
+
+	public List<String> getSymbols() {
+		return symbols;
+	}
+
+	private static List<String> getNumbers() {
+		List<String> sym = new ArrayList<>();
+		for (int i = 1; i <= 100; i++) {
+			sym.add(Integer.toString(i));
+		}
+		return sym;
+	}
+
+	private static List<String> getLetters() {
+		List<String> sym = new ArrayList<>();
+		for (int i = 0; i < 100; i++) {
+			int currentOffset = i;
+			String letter = "";
+			while (currentOffset >= 26) {
+				letter += Character.toString((char) ('A' + currentOffset % 26));
+				currentOffset /= 26;
+				currentOffset--;
+			}
+			letter += Character.toString((char) ('A' + currentOffset % 26));
+			sym.add(new StringBuilder(letter).reverse().toString());
+		}
+		return sym;
+	}
+
+	private static List<String> getRussian() {
+		List<String> sym = new ArrayList<>();
+		for (int i = 0; i < 100; i++) {
+			sym.add(new String(Character.toChars(0X0400 + i)));
+		}
+		return sym;
+	}
+
+	private static List<String> getEmojis() {
+		List<String> sym = new ArrayList<>();
+		for (int i = 0; i < 100; i++) {
+			sym.add(new String(Character.toChars(0X1F600 + i)));
+		}
+		return sym;
+	}
+
+	private static final String[] symbolNames;
+
+	static {
+		Symbols[] symbols = Symbols.values();
+		symbolNames = new String[symbols.length];
+		for (int i = 0; i < symbols.length; i++) {
+			symbolNames[i] = symbols[i].getDisplayName();
+		}
+	}
+
+	public static String[] getSymbolsNames() {
+		return symbolNames;
+	}
+
+}

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

@@ -0,0 +1,33 @@
+package gui.menu;
+
+import imgui.ImGui;
+
+public abstract class BaseView {
+
+	protected final StateMachine stateMachine;
+
+	public BaseView(StateMachine stateMachine) {
+		this.stateMachine = stateMachine;
+	}
+
+	public abstract void render();
+
+	public void cleanResources() {}
+
+	public void closeMenu(int count) {
+		for (int i = 0; i < count; i++) {
+			this.stateMachine.popState();
+		}
+	}
+
+	public void closeMenu() {
+		closeMenu(1);
+	}
+
+	protected void renderReturnButton() {
+		if (ImGui.button("Retour")) {
+			closeMenu();
+		}
+	}
+
+}

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

@@ -0,0 +1,105 @@
+package gui.menu;
+
+import java.io.IOException;
+import java.net.UnknownHostException;
+
+import imgui.ImGui;
+import network.client.Client;
+import network.server.Server;
+
+public class ConnexionStatusView extends BaseView {
+
+	private Client client;
+	private Server server;
+
+	private String displayText = "Connecting ...";
+
+	public ConnexionStatusView(StateMachine stateMachine, String address, short port)
+			throws UnknownHostException, IOException {
+		super(stateMachine);
+		Thread t = new Thread(() -> {
+			try {
+				this.client = new Client(address, port);
+				bindListeners();
+			} catch (IOException e) {
+				e.printStackTrace();
+				onDisconnect();
+			}
+		});
+		t.start();
+	}
+
+	public ConnexionStatusView(StateMachine stateMachine, short port) throws UnknownHostException, IOException {
+		super(stateMachine);
+		Thread t = new Thread(() -> {
+			try {
+				this.server = new Server(port);
+				this.client = new Client("localhost", port);
+				bindListeners();
+			} catch (IOException e) {
+				e.printStackTrace();
+				onDisconnect();
+			}
+		});
+		t.start();
+	}
+
+	private void bindListeners() {
+		this.client.onConnect.connect(this::onConnect);
+		this.client.onClosed.connect(this::onLeave);
+		this.client.onDisconnect.connect(this::onDisconnect);
+	}
+
+	private ConnexionStatusView(StateMachine stateMachine, Server server, Client client) {
+		super(stateMachine);
+		this.client = client;
+		this.server = server;
+	}
+
+	public void onConnect() {
+		this.stateMachine.pushState(new MultiPlayerView(stateMachine, client, server));
+	}
+
+	public void onDisconnect() {
+		if (client != null) {
+			String reason = client.getDisconnectReason();
+			if (reason == null)
+				displayText = "Le serveur a fermé la connexion !";
+			else
+				displayText = "Vous avez été déconnecté ! Raison : " + client.getDisconnectReason();
+		} else {
+			displayText = "La connexion a échoué !";
+		}
+
+	}
+
+	public void onLeave() {
+		this.client = null;
+		// on passe le menu de la connexion
+		this.closeMenu();
+	}
+
+	@Override
+	public void render() {
+		ImGui.text(displayText);
+		renderReturnButton();
+	}
+
+	@Override
+	public void closeMenu() {
+		super.closeMenu();
+		cleanResources();
+	}
+
+	@Override
+	public void cleanResources() {
+		// System.out.println("Bye bye !");
+		if (this.server != null) {
+			this.server.stop();
+		}
+		if (this.client != null) {
+			this.client.stop();
+		}
+	}
+
+}

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

@@ -0,0 +1,37 @@
+package gui.menu;
+
+import imgui.ImGui;
+import imgui.ImVec2;
+
+public class MainMenu extends BaseView {
+
+	public MainMenu(StateMachine stateMachine) {
+		super(stateMachine);
+	}
+
+	@Override
+	public void render() {
+		var displaySize = ImGui.getIO().getDisplaySize();
+		ImVec2 buttonSize = new ImVec2(500, 150);
+		int paddingHeight = 20;
+
+		float centerX = displaySize.x / 2.0f - buttonSize.x / 2.0f;
+		float centerY = displaySize.y / 2.0f - buttonSize.y / 2.0f;
+
+		ImGui.setCursorPos(centerX, centerY - buttonSize.y - paddingHeight);
+		if (ImGui.button("Mode histoire", buttonSize)) {
+			this.stateMachine.pushState(new SoloMenu(this.stateMachine));
+		}
+		
+		ImGui.setCursorPos(centerX, centerY);
+		if (ImGui.button("Multijoueur", buttonSize)) {
+			this.stateMachine.pushState(new MultiMenu(this.stateMachine));
+		}
+		
+		ImGui.setCursorPos(centerX, centerY + buttonSize.y + paddingHeight);
+		if (ImGui.button("Options", buttonSize)) {
+			this.stateMachine.pushState(new OptionsMenu(this.stateMachine));
+		}
+	}
+
+}

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

@@ -0,0 +1,68 @@
+package gui.menu;
+
+import java.io.IOException;
+
+import imgui.ImGui;
+import imgui.ImVec2;
+import imgui.type.ImInt;
+import imgui.type.ImString;
+
+public class MultiMenu extends BaseView {
+
+	private final ImInt port = new ImInt(25565);
+	private final ImString address = new ImString("localhost");
+
+	public MultiMenu(StateMachine stateMachine) {
+		super(stateMachine);
+		address.resize(20);
+	}
+
+	private void renderCreate() {
+		ImVec2 displaySize = ImGui.getIO().getDisplaySize();
+		ImGui.beginChild("##CreateGame", new ImVec2(displaySize.x / 2.0f, displaySize.y * 8.0f / 9.0f));
+		ImGui.inputInt("Port", port);
+		if (ImGui.button("Créer")) {
+			try {
+				this.stateMachine.pushState(new ConnexionStatusView(stateMachine, (short) port.get()));
+			} catch (IOException e) {
+				e.printStackTrace();
+			}
+		}
+		ImGui.endChild();
+	}
+
+	private void renderJoin() {
+		ImVec2 displaySize = ImGui.getIO().getDisplaySize();
+		ImGui.beginChild("##JoinGame", new ImVec2(displaySize.x / 2.0f, displaySize.y * 8.0f / 9.0f));
+		ImGui.inputText("Adresse", address);
+		ImGui.inputInt("Port", port);
+		if (ImGui.button("Rejoindre")) {
+			try {
+				this.stateMachine.pushState(new ConnexionStatusView(stateMachine, address.get(), (short) port.get()));
+			} catch (IOException e) {
+				// TODO Auto-generated catch block
+				e.printStackTrace();
+			}
+		}
+		ImGui.endChild();
+	}
+
+	@Override
+	public void render() {
+
+		renderCreate();
+		ImGui.sameLine();
+		renderJoin();
+
+		ImVec2 displaySize = ImGui.getIO().getDisplaySize();
+		ImVec2 buttonSize = new ImVec2(500, 70.0f);
+
+		float centerX = displaySize.x / 2.0f - buttonSize.x / 2.0f;
+
+		ImGui.setCursorPosX(centerX);
+		if (ImGui.button("Retour", buttonSize)) {
+			closeMenu();
+		}
+	}
+
+}

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

@@ -0,0 +1,37 @@
+package gui.menu;
+
+import gui.SudokuRenderer;
+import imgui.ImGui;
+import network.client.Client;
+import network.server.Server;
+
+public class MultiPlayerDokuView extends BaseView{
+
+	private final Client client;
+	private final Server server;
+	private final SudokuRenderer sudokuRenderer;
+
+	public MultiPlayerDokuView(StateMachine stateMachine, Client client, Server server) {
+		super(stateMachine);
+		this.client = client;
+		this.server = server;
+		this.sudokuRenderer = new SudokuRenderer(this.client.getGame().getDoku());
+		this.client.onDisconnect.connect(this::onDisconnect);
+	}
+
+	public void onDisconnect() {
+		if (server == null) {
+			closeMenu();
+		}
+	}
+
+	@Override
+	public void render() {
+		this.sudokuRenderer.render();
+		if (ImGui.button("Quitter")) {
+			this.client.stop();
+			this.closeMenu(3);
+		}
+	}
+
+}

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

@@ -0,0 +1,60 @@
+package gui.menu;
+
+import java.util.Arrays;
+
+import game.Player;
+import imgui.ImGui;
+import network.client.Client;
+import network.server.Server;
+import sudoku.constraint.Constraint;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;
+
+public class MultiPlayerView extends BaseView {
+
+	private final Client client;
+	private final Server server;
+
+	public MultiPlayerView(StateMachine stateMachine, Client client, Server server) {
+		super(stateMachine);
+		this.client = client;
+		this.server = server;
+		this.client.onDisconnect.connect(this::onDisconnect);
+		this.client.onGameStarted
+				.connect(() -> this.stateMachine.pushState(new MultiPlayerDokuView(stateMachine, client, server)));
+	}
+
+	@Override
+	public void closeMenu() {
+		this.client.forceDisconnect();
+		super.closeMenu();
+	}
+
+	public void onDisconnect() {
+		this.stateMachine.popState();
+	}
+
+	public void renderGameStatus() {
+		if (this.server == null) {
+			ImGui.text("En attente de l'administrateur du serveur ...");
+		} else {
+			if (ImGui.button("Démarrer")) {
+				// temp
+				MultiDoku doku = SudokuFactory.createBasicXShapedMultidoku(3, Arrays.asList(Constraint.Diagonal));
+				this.server.startGame(doku);
+			}
+		}
+	}
+
+	@Override
+	public void render() {
+		ImGui.text("Joueurs :");
+		{
+			for (Player player : this.client.getGame().getPlayers().values()) {
+				ImGui.bulletText(player.getPseudo());
+			}
+		}
+		renderGameStatus();
+	}
+
+}

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

@@ -0,0 +1,25 @@
+package gui.menu;
+
+import gui.Options;
+import gui.Symbols;
+import imgui.ImGui;
+import imgui.type.ImInt;
+
+public class OptionsMenu extends BaseView {
+
+	private ImInt currentValue = new ImInt();
+
+	public OptionsMenu(StateMachine stateMachine) {
+		super(stateMachine);
+	}
+
+	@Override
+	public void render() {
+		ImGui.text("Options");
+		if(ImGui.combo("Jeu de symboles", currentValue, Symbols.getSymbolsNames())){
+			Options.Symboles = Symbols.values()[currentValue.get()];
+		}
+		renderReturnButton();
+	}
+
+}

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

@@ -0,0 +1,27 @@
+package gui.menu;
+
+import gui.SudokuSelector;
+import imgui.ImGui;
+
+public class SoloMenu extends BaseView {
+
+	private final SudokuSelector sudokuSelector;
+
+	public SoloMenu(StateMachine stateMachine) {
+		super(stateMachine);
+		this.sudokuSelector = new SudokuSelector(true);
+		this.sudokuSelector.onSelect.connect(this::pushSudokuState);
+	}
+
+	private void pushSudokuState() {
+		this.stateMachine.pushState(new SudokuView(stateMachine, this.sudokuSelector.getDoku()));
+	}
+
+	@Override
+	public void render() {
+		ImGui.text("Solo");
+		sudokuSelector.render();
+		renderReturnButton();
+	}
+
+}

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

@@ -0,0 +1,59 @@
+package gui.menu;
+
+import java.util.Stack;
+
+import gui.Images;
+import imgui.ImGui;
+import imgui.ImVec2;
+import imgui.flag.ImGuiKey;
+import imgui.flag.ImGuiWindowFlags;
+
+public class StateMachine {
+
+	private final Stack<BaseView> menus;
+
+	public StateMachine() {
+		this.menus = new Stack<>();
+	}
+
+	public void clear() {
+		for (BaseView view : menus) {
+			view.cleanResources();
+		}
+		menus.clear();
+	}
+
+	public void pushState(BaseView menu) {
+		menus.add(menu);
+	}
+
+	public void popState() {
+		menus.getLast().cleanResources();
+		menus.pop();
+	}
+
+	private void checkEscape() {
+		if (ImGui.isKeyPressed(ImGuiKey.Escape) && menus.size() > 1) {
+			menus.getLast().closeMenu();
+		}
+	}
+
+	public void render() {
+		var displaySize = ImGui.getIO().getDisplaySize();
+		ImGui.setNextWindowPos(new ImVec2(0.0f, 0.0f));
+		ImGui.setNextWindowSize(displaySize);
+		ImGui.begin("Background", null, ImGuiWindowFlags.NoDecoration | ImGuiWindowFlags.NoMove
+		| ImGuiWindowFlags.NoSavedSettings | ImGuiWindowFlags.NoBackground  | ImGuiWindowFlags.NoBringToFrontOnFocus | ImGuiWindowFlags.NoInputs);
+		ImGui.image(Images.BACKGROUND, displaySize, new ImVec2(0, 0));
+		ImGui.end();
+		ImGui.setNextWindowPos(new ImVec2(0.0f, 0.0f));
+		ImGui.setNextWindowSize(displaySize);
+		ImGui.begin("##Main Window", null, ImGuiWindowFlags.NoDecoration | ImGuiWindowFlags.NoMove
+				| ImGuiWindowFlags.NoSavedSettings | ImGuiWindowFlags.NoBackground);
+		menus.get(menus.size() - 1).render();
+		ImGui.end();
+		// ImGui.showDemoWindow();
+		checkEscape();
+	}
+
+}

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

@@ -0,0 +1,146 @@
+package gui.menu;
+
+import java.util.concurrent.CancellationException;
+
+import gui.SudokuRenderer;
+import imgui.ImGui;
+import imgui.ImGuiStyle;
+import sudoku.io.SudokuSerializer;
+import sudoku.solver.BacktrackingSolver;
+import sudoku.solver.HumanSolver;
+import sudoku.solver.MixedSolver;
+import sudoku.solver.Solver;
+import sudoku.structure.MultiDoku;
+
+public class SudokuView extends BaseView {
+
+	private final SudokuRenderer sudokuRenderer;
+	private Thread resolveThread;
+	private final MultiDoku doku;
+	private String lastSavePath = null;
+
+	private boolean resolved = false;
+
+	public SudokuView(StateMachine stateMachine, MultiDoku doku) {
+		super(stateMachine);
+		this.doku = doku;
+		this.sudokuRenderer = new SudokuRenderer(doku);
+		this.sudokuRenderer.onResolve.connect(this::onResolve);
+	}
+
+	private void onResolve() {
+		this.resolved = true;
+	}
+
+	private void stopResolve() {
+		if (resolveThread != null && resolveThread.isAlive()) {
+			resolveThread.interrupt();
+			resolveThread = null;
+		}
+	}
+
+	boolean centeredButton(String label) {
+		ImGuiStyle style = ImGui.getStyle();
+
+		float size = ImGui.calcTextSizeX(label) + style.getFramePaddingX() * 2.0f;
+		float avail = ImGui.getContentRegionAvailX();
+
+		float off = (avail - size) * 0.5f;
+		if (off > 0.0f)
+			ImGui.setCursorPosX(ImGui.getCursorPosX() + off);
+
+		return ImGui.button(label);
+	}
+
+	private void renderCancelButton() {
+		boolean wantsToStop = false;
+		if (resolveThread != null && resolveThread.isAlive()) {
+			// ImGui.endDisabled();
+			if (centeredButton("Annuler")) {
+				// we can't stop the Thread right now
+				wantsToStop = true;
+			}
+		}
+		if (resolveThread != null && !resolveThread.isAlive()) {
+			resolveThread.start();
+		}
+		if (wantsToStop)
+			stopResolve();
+	}
+
+	private void startSolve(Solver solver) {
+		resolveThread = new Thread(() -> {
+			try {
+				solver.solve(this.doku);
+			} catch (CancellationException e) {
+				System.out.println("The user is bored !");
+			}
+			stopResolve();
+		});
+	}
+
+	private void renderSolvePopup() {
+		if (ImGui.beginPopup("solve")) {
+			if (ImGui.button("Résoudre avec backtrace")) {
+				startSolve(new BacktrackingSolver());
+				ImGui.closeCurrentPopup();
+			}
+			if (ImGui.button("Résoudre avec déduction")) {
+				startSolve(new HumanSolver());
+				ImGui.closeCurrentPopup();
+			}
+			if (ImGui.button("Résoudre avec déduction et backtrace")) {
+				startSolve(new MixedSolver());
+				ImGui.closeCurrentPopup();
+			}
+			ImGui.endPopup();
+		}
+	}
+
+	private void renderSolveButton() {
+		if (resolveThread != null)
+			ImGui.beginDisabled();
+
+		if (!this.resolved && centeredButton("Résoudre")) {
+			// beginSolve = true;
+			ImGui.openPopup("solve");
+		}
+
+		if (resolveThread != null)
+			ImGui.endDisabled();
+
+		if (this.resolved) {
+			ImGui.text("Bravo !");
+		}
+
+		renderSolvePopup();
+	}
+
+	private void renderSaveButton() {
+		if (ImGui.button("Sauvegarder l'état de la grille")) {
+			lastSavePath = SudokuSerializer.saveMultiDoku(doku);
+			ImGui.openPopup("saveDone");
+		}
+		if (ImGui.beginPopup("saveDone")) {
+			ImGui.text("Sudoku sauvegardé dans ");
+			ImGui.text(lastSavePath);
+			ImGui.endPopup();
+		}
+	}
+
+	@Override
+	public void render() {
+		sudokuRenderer.render();
+		renderSolveButton();
+		renderSaveButton();
+		renderCancelButton();
+		renderReturnButton();
+	}
+
+	@Override
+	public void closeMenu() {
+		super.closeMenu();
+		stopResolve();
+	}
+
+}

app/src/main/java/network/Connexion.java

@@ -0,0 +1,40 @@
+package network;
+
+import java.io.IOException;
+import java.io.ObjectOutputStream;
+import java.net.Socket;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+
+public abstract class Connexion implements PacketVisitor {
+	
+	final Socket socket;
+	private final ObjectOutputStream objectOutputStream;
+	private final ConnexionThread connexionThread;
+
+	public Connexion(Socket socket) throws IOException {
+		this.socket = socket;
+		this.objectOutputStream = new ObjectOutputStream(this.socket.getOutputStream());
+		this.connexionThread = new ConnexionThread(this);
+		this.connexionThread.start();
+	}
+
+	public boolean isClosed() {
+		return this.socket.isClosed();
+	}
+
+	public synchronized void sendPacket(Packet packet) {
+		try {
+			objectOutputStream.writeObject(packet);
+			objectOutputStream.flush();
+		} catch (IOException e) {
+			System.err.println("Error while sending packet ! " + e.getLocalizedMessage());
+			close();
+		}
+	}
+
+	public void close() {
+		this.connexionThread.cancel();
+	}
+}

app/src/main/java/network/ConnexionThread.java

@@ -0,0 +1,44 @@
+package network;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+
+import network.protocol.Packet;
+
+public class ConnexionThread extends Thread {
+
+	private final Connexion connexion;
+	private final ObjectInputStream objectInputStream;
+
+	public ConnexionThread(Connexion connexion) throws IOException {
+		this.connexion = connexion;
+		this.objectInputStream = new ObjectInputStream(this.connexion.socket.getInputStream());
+	}
+
+	@Override
+	public void run() {
+		while (!interrupted()) {
+			try {
+				// System.out.println(objectInputStream.available());
+				Object o = objectInputStream.readObject();
+				if (o instanceof Packet packet) {
+					connexion.visitPacket(packet);
+				}
+			} catch (ClassNotFoundException | IOException e) {
+				e.printStackTrace();
+				this.connexion.close();
+				break;
+			}
+		}
+	}
+
+	public void cancel() {
+		try {
+			objectInputStream.close();
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+		interrupt();
+	}
+
+}

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

@@ -0,0 +1,57 @@
+package network.client;
+
+import java.io.IOException;
+import java.net.UnknownHostException;
+import java.util.Random;
+
+import common.Signal;
+import game.Game;
+import game.Player;
+import network.protocol.packets.LoginPacket;
+
+public class Client {
+	private final ClientConnexion clientConnection;
+	private final Game game;
+
+	public final Signal onConnect = new Signal();
+	public final Signal onDisconnect = new Signal();
+	public final Signal onClosed = new Signal();
+	public final Signal onGameStarted = new Signal();
+
+	String disconnectReason = null;
+
+	public Client(String address, short port) throws UnknownHostException, IOException {
+		this.clientConnection = new ClientConnexion(address, port, this);
+		this.game = new Game();
+		// temp
+		Random r = new Random();
+		login("Player" + r.nextInt());
+	}
+
+	public void login(String pseudo) {
+		System.out.println("Logging in with pseudo " + pseudo + " ...");
+		this.clientConnection.sendPacket(new LoginPacket(pseudo));
+	}
+
+	public void stop() {
+		this.clientConnection.close();
+	}
+
+	public void addPlayer(Player player) {
+		this.game.addPlayer(player);
+	}
+
+	public Game getGame() {
+		return game;
+	}
+
+	public String getDisconnectReason() {
+		return disconnectReason;
+	}
+
+	public void forceDisconnect() {
+		this.onClosed.emit();
+		stop();
+	}
+
+}

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

@@ -0,0 +1,76 @@
+package network.client;
+
+import java.io.IOException;
+import java.net.Socket;
+import java.net.UnknownHostException;
+
+import game.Player;
+import network.Connexion;
+import network.protocol.packets.ConnexionInfoPacket;
+import network.protocol.packets.DisconnectPacket;
+import network.protocol.packets.KeepAlivePacket;
+import network.protocol.packets.LoginPacket;
+import network.protocol.packets.PlayerJoinPacket;
+import network.protocol.packets.PlayerLeavePacket;
+import network.protocol.packets.StartGamePacket;
+import sudoku.io.SudokuSerializer;
+
+public class ClientConnexion extends Connexion {
+
+	private final Client client;
+	private Player player = null;
+
+	public ClientConnexion(String address, short port, Client client) throws UnknownHostException, IOException {
+		super(new Socket(address, port));
+		this.client = client;
+	}
+
+	@Override
+	public void close() {
+		if (!this.isClosed()) {
+			super.close();
+			client.onDisconnect.emit();
+		}
+	}
+
+	@Override
+	public void visitPacket(ConnexionInfoPacket packet) {
+		this.player = this.client.getGame().getPlayerById(packet.getConnectionId());
+		client.onConnect.emit();
+	}
+
+	@Override
+	public void visitPacket(KeepAlivePacket packet) {
+		// we just send the packet back to the server
+		sendPacket(packet);
+	}
+
+	@Override
+	public void visitPacket(DisconnectPacket packet) {
+		this.client.disconnectReason = packet.getReason();
+		close();
+	}
+
+	@Override
+	public void visitPacket(LoginPacket packet) {
+		throw new UnsupportedOperationException("Unimplemented method 'visitPacketLogin'");
+	}
+
+	@Override
+	public void visitPacket(PlayerJoinPacket packet) {
+		this.client.addPlayer(packet.getPlayer());
+		System.out.println("[Client] " + packet.getPlayer().getPseudo() + " joined the game !");
+	}
+
+	@Override
+	public void visitPacket(PlayerLeavePacket packet) {
+		this.client.getGame().removePlayer(packet.getPlayer());
+	}
+
+	@Override
+	public void visitPacket(StartGamePacket packet) {
+		this.client.getGame().startGame(SudokuSerializer.deserializeSudoku(packet.getSerializedSudoku()));
+		this.client.onGameStarted.emit();
+	}
+
+}

app/src/main/java/network/protocol/Packet.java

@@ -0,0 +1,11 @@
+package network.protocol;
+
+import java.io.Serializable;
+
+public abstract class Packet implements Serializable {
+
+	// public abstract int getId();
+
+	public abstract void accept(PacketVisitor packetVisitor);
+
+}

app/src/main/java/network/protocol/PacketVisitor.java

@@ -0,0 +1,25 @@
+package network.protocol;
+
+import network.protocol.packets.ConnexionInfoPacket;
+import network.protocol.packets.DisconnectPacket;
+import network.protocol.packets.KeepAlivePacket;
+import network.protocol.packets.LoginPacket;
+import network.protocol.packets.PlayerJoinPacket;
+import network.protocol.packets.PlayerLeavePacket;
+import network.protocol.packets.StartGamePacket;
+
+public interface PacketVisitor {
+
+	default void visitPacket(Packet packet) {
+		packet.accept(this);
+	}
+	
+	void visitPacket(ConnexionInfoPacket packet);
+	void visitPacket(DisconnectPacket packet);
+	void visitPacket(KeepAlivePacket packet);
+	void visitPacket(LoginPacket packet);
+	void visitPacket(PlayerJoinPacket packet);
+	void visitPacket(PlayerLeavePacket packet);
+	void visitPacket(StartGamePacket packet);
+	
+}

app/src/main/java/network/protocol/Packets.java

@@ -0,0 +1,7 @@
+package network.protocol;
+
+public enum Packets {
+
+	ConnectionInfo, KeepAlive, Disconnect, Login, PlayerJoin, PlayerLeave, StartGame
+
+}

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

@@ -0,0 +1,25 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class ConnexionInfoPacket extends Packet {
+
+	static private final long serialVersionUID = Packets.ConnectionInfo.ordinal();
+
+	private final int connectionId;
+
+	public ConnexionInfoPacket(int connectionId) {
+		this.connectionId = connectionId;
+	}
+
+	public int getConnectionId() {
+		return connectionId;
+	}
+	
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+}

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

@@ -0,0 +1,26 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class DisconnectPacket extends Packet {
+
+	static private final long serialVersionUID = Packets.Disconnect.ordinal();
+
+	private final String reason;
+
+	public DisconnectPacket(String reason) {
+		this.reason = reason;
+	}
+
+	public String getReason() {
+		return reason;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+}

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

@@ -0,0 +1,26 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class KeepAlivePacket extends Packet {
+
+	static private final long serialVersionUID = Packets.KeepAlive.ordinal();
+
+	private final long keepAliveId;
+
+	public KeepAlivePacket(long keepAliveId) {
+		this.keepAliveId = keepAliveId;
+	}
+
+	public long getKeepAliveId() {
+		return keepAliveId;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+}

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

@@ -0,0 +1,26 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class LoginPacket extends Packet {
+
+	static private final long serialVersionUID = Packets.Login.ordinal();
+
+	private final String pseudo;
+
+	public LoginPacket(String pseudo) {
+		this.pseudo = pseudo;
+	}
+
+	public String getPseudo() {
+		return pseudo;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+}

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

@@ -0,0 +1,29 @@
+package network.protocol.packets;
+
+import game.Player;
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class PlayerJoinPacket extends Packet{
+
+	static private final long serialVersionUID = Packets.PlayerJoin.ordinal();
+
+	private final Player player;
+
+	public PlayerJoinPacket(Player player) {
+		this.player = player;
+	}
+
+	public Player getPlayer() {
+		return player;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+	
+
+}

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

@@ -0,0 +1,28 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class PlayerLeavePacket extends Packet{
+
+	static private final long serialVersionUID = Packets.PlayerLeave.ordinal();
+
+	private final int playerId;
+
+	public PlayerLeavePacket(int playerId) {
+		this.playerId = playerId;
+	}
+
+	public int getPlayer() {
+		return playerId;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+	
+
+}

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

@@ -0,0 +1,26 @@
+package network.protocol.packets;
+
+import network.protocol.Packet;
+import network.protocol.PacketVisitor;
+import network.protocol.Packets;
+
+public class StartGamePacket extends Packet {
+
+	static private final long serialVersionUID = Packets.StartGame.ordinal();
+
+	private final String serializedSudoku;
+
+	public StartGamePacket(String serializedSudoku) {
+		this.serializedSudoku = serializedSudoku;
+	}
+
+	public String getSerializedSudoku() {
+		return serializedSudoku;
+	}
+
+	@Override
+	public void accept(PacketVisitor packetVisitor) {
+		packetVisitor.visitPacket(this);
+	}
+
+}

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

@@ -0,0 +1,49 @@
+package network.server;
+
+import java.util.Random;
+
+import network.protocol.packets.KeepAlivePacket;
+
+public class KeepAliveHandler {
+
+	private final ServerConnexion serverConnexion;
+
+	private static final int KEEP_ALIVE_COOLDOWN = 5 * 1000;
+
+	private long lastKeepAlive = 0;
+	private long lastSend = 0;
+	private volatile boolean keepAliveRecieved = false;
+
+	public KeepAliveHandler(ServerConnexion serverConnexion) {
+		this.serverConnexion = serverConnexion;
+		sendKeepAlive();
+	}
+
+	public boolean update() {
+		var currentTime = System.currentTimeMillis();
+		if (currentTime - lastSend > KEEP_ALIVE_COOLDOWN) {
+			if (keepAliveRecieved) {
+				sendKeepAlive();
+			} else {
+				System.out.println("Zombie");
+				serverConnexion.close();
+				return false;
+			}
+		}
+		return true;
+	}
+
+	public void recievedKeepAlive(long keepAliveId) {
+		if (lastKeepAlive == keepAliveId)
+			this.keepAliveRecieved = true;
+	}
+
+	private void sendKeepAlive() {
+		Random r = new Random();
+		lastKeepAlive = r.nextLong();
+		lastSend = System.currentTimeMillis();
+		keepAliveRecieved = false;
+		this.serverConnexion.sendPacket(new KeepAlivePacket(lastKeepAlive));
+	}
+
+}

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

@@ -0,0 +1,76 @@
+package network.server;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.util.ArrayList;
+import java.util.List;
+
+import game.Game;
+import game.Player;
+import network.protocol.Packet;
+import network.protocol.packets.StartGamePacket;
+import sudoku.io.SudokuSerializer;
+import sudoku.structure.MultiDoku;
+
+public class Server {
+
+	final ServerSocket serverSocket;
+	final List<ServerConnexion> connexions;
+	private final ServerAcceptThread acceptThread;
+	private final ServerLogicThread logicThread;
+	private final Game game;
+	private int nextPlayerId = 0;
+
+	public Server(short port) throws IOException {
+		this.serverSocket = new ServerSocket(port);
+		this.connexions = new ArrayList<>();
+		this.acceptThread = new ServerAcceptThread(this);
+		this.acceptThread.start();
+		this.logicThread = new ServerLogicThread(this);
+		this.logicThread.start();
+		this.game = new Game();
+	}
+
+	public void broadcastPacket(Packet packet) {
+		for (ServerConnexion connexion : this.connexions) {
+			connexion.sendPacket(packet);
+		}
+	}
+
+	public void update() {
+		for (var it = connexions.iterator(); it.hasNext();) {
+			ServerConnexion connexion = it.next();
+			if (!connexion.update()) {
+				connexion.close();
+				connexion.nukeConnection();
+				it.remove();
+			}
+		}
+	}
+
+	public void stop() {
+		this.acceptThread.cancel();
+		this.logicThread.cancel();
+		for (ServerConnexion connexion : this.connexions) {
+			connexion.nukeConnection();
+			connexion.close();
+		}
+	}
+
+	public Player addPlayer(String pseudo) {
+		Player p = new Player(nextPlayerId, pseudo);
+		this.game.addPlayer(p);
+		nextPlayerId++;
+		return p;
+	}
+
+	public Game getGame() {
+		return game;
+	}
+
+	public void startGame(MultiDoku doku) {
+		this.game.startGame(doku);
+		broadcastPacket(new StartGamePacket(SudokuSerializer.serializeSudoku(doku).toString()));
+	}
+
+}

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

@@ -0,0 +1,36 @@
+package network.server;
+
+import java.io.IOException;
+import java.net.Socket;
+
+public class ServerAcceptThread extends Thread {
+
+	private final Server server;
+
+	public ServerAcceptThread(Server server) {
+		this.server = server;
+	}
+
+	public void cancel() {
+		try {
+			this.server.serverSocket.close();
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+		interrupt();
+	}
+
+	@Override
+	public void run() {
+		try {
+			while(!interrupted()) {
+				Socket newConnection = this.server.serverSocket.accept();
+				ServerConnexion serverConnection = new ServerConnexion(newConnection, this.server);
+				this.server.connexions.add(serverConnection);
+			}
+		} catch(IOException e) {
+			// e.printStackTrace();
+		}
+	}
+
+}

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

@@ -0,0 +1,105 @@
+package network.server;
+
+import java.io.IOException;
+import java.net.Socket;
+
+import game.Player;
+import game.Game.GameState;
+import network.Connexion;
+import network.protocol.packets.ConnexionInfoPacket;
+import network.protocol.packets.DisconnectPacket;
+import network.protocol.packets.KeepAlivePacket;
+import network.protocol.packets.LoginPacket;
+import network.protocol.packets.PlayerJoinPacket;
+import network.protocol.packets.PlayerLeavePacket;
+import network.protocol.packets.StartGamePacket;
+import sudoku.io.SudokuSerializer;
+
+public class ServerConnexion extends Connexion {
+
+	private final Server server;
+	private final KeepAliveHandler keepAliveHandler;
+	private boolean shouldClose = false;
+	private Player player = null;
+
+	public ServerConnexion(Socket socket, Server server) throws IOException {
+		super(socket);
+		this.server = server;
+		this.keepAliveHandler = new KeepAliveHandler(this);
+	}
+
+	public boolean update() {
+		if (shouldClose | isClosed())
+			return false;
+		return this.keepAliveHandler.update();
+	}
+
+	public void nukeConnection() {
+		if (player != null) {
+			sendPacket(new DisconnectPacket("Le serveur a été fermé !"));
+			this.server.broadcastPacket(new PlayerLeavePacket(player.getId()));
+			this.server.getGame().removePlayer(player.getId());
+		}
+	}
+
+	@Override
+	public synchronized void close() {
+		if(shouldClose)
+			return;
+		super.close();
+		shouldClose = true;
+		System.out.println("[Server] Closing connexion !");
+	}
+
+	private void finishLogin() {
+		// send players that have already joined (excluding this one)
+		for (Player p : this.server.getGame().getPlayers().values()) {
+			if (p.getId() != player.getId())
+				sendPacket(new PlayerJoinPacket(p));
+		}
+		this.server.broadcastPacket(new PlayerJoinPacket(player));
+		sendPacket(new ConnexionInfoPacket(player.getId()));
+		if (this.server.getGame().getGameState() == GameState.GameGoing) {
+			sendPacket(new StartGamePacket(SudokuSerializer.serializeSudoku(this.server.getGame().getDoku()).toString()));
+		}
+	}
+
+	@Override
+	public void visitPacket(KeepAlivePacket packet) {
+		this.keepAliveHandler.recievedKeepAlive(packet.getKeepAliveId());
+	}
+
+	@Override
+	public void visitPacket(DisconnectPacket packet) {
+		close();
+	}
+
+	@Override
+	public void visitPacket(LoginPacket packet) {
+		if (this.player != null)
+			return;
+		this.player = this.server.addPlayer(packet.getPseudo());
+		finishLogin();
+	}
+
+	@Override
+	public void visitPacket(ConnexionInfoPacket packet) {
+		throw new UnsupportedOperationException("Unimplemented method 'visitPacketConnexionInfo'");
+	}
+
+	@Override
+	public void visitPacket(PlayerJoinPacket packet) {
+		throw new UnsupportedOperationException("Unimplemented method 'visitPacketPlayerJoin'");
+	}
+
+	@Override
+	public void visitPacket(PlayerLeavePacket packet) {
+		throw new UnsupportedOperationException("Unimplemented method 'visitPacketPlayerLeave'");
+	}
+
+	@Override
+	public void visitPacket(StartGamePacket packet) {
+		throw new UnsupportedOperationException("Unimplemented method 'visitPacketStartGame'");
+	}
+
+}

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

@@ -0,0 +1,28 @@
+package network.server;
+
+public class ServerLogicThread extends Thread {
+
+	private final Server server;
+
+	public ServerLogicThread(Server server) {
+		this.server = server;
+	}
+
+	public void cancel() {
+		interrupt();
+	}
+
+	@Override
+	public void run() {
+		while (!interrupted()) {
+			server.update();
+			try {
+				Thread.sleep(50);
+			} catch (InterruptedException e) {
+				// e.printStackTrace();
+				break;
+			}
+		}
+	}
+
+}

app/src/main/java/sudoku/Block.java

@@ -1,26 +0,0 @@
-package sudoku;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class Block {
-
-	private final List<Cell> cells;
-
-	public Block(List<Cell> cells) {
-		this.cells = cells;
-	}
-
-	public Block() {
-		this.cells = new ArrayList<>();
-	}
-
-	public List<Cell> getCells() {
-		return cells;
-	}
-
-	void addCell(Cell newCell) {
-		this.cells.add(newCell);
-	}
-
-}

app/src/main/java/sudoku/Cell.java

@@ -1,39 +0,0 @@
-package sudoku;
-
-public abstract class Cell {
-
-	protected static int NOSYMBOLE = -1;
-	protected int symboleIndex;
-	protected Block block = null;
-
-	public Cell(int symboleIndex) {
-		this.symboleIndex = symboleIndex;
-	}
-
-	/**
-	 * @brief Default constructor, empty square
-	 */
-	public Cell() {
-		this(NOSYMBOLE);
-	}
-
-	public int getSymboleIndex() {
-		return symboleIndex;
-	}
-
-	public Block getBlock() {
-		return this.block;
-	}
-
-	// only SudokuFactory should access this
-	void setBlock(Block block) {
-		this.block = block;
-	}
-
-	@Override
-	public boolean equals(Object obj) {
-		if (obj instanceof Cell otherCell)
-			return otherCell.getSymboleIndex() == this.getSymboleIndex();
-		return false;
-	}
-}

app/src/main/java/sudoku/ImmutableCell.java

@@ -1,9 +0,0 @@
-package sudoku;
-
-public class ImmutableCell extends Cell {
-
-	public ImmutableCell(int symboleIndex) {
-		super(symboleIndex);
-	}
-
-}

app/src/main/java/sudoku/Main.java

@@ -3,18 +3,40 @@
  */
 package sudoku;
 
+import gui.RenderableMultidoku;
+import gui.Symbols;
+import sudoku.io.ConsoleInterface;
 import sudoku.io.SudokuPrinter;
+import sudoku.solver.RandomSolver;
+import sudoku.solver.Solver;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;
+
+import java.util.Random;
 
 public class Main {
     public String getGreeting() {
         return "Hello World!";
     }
 
+    public static void voidTest(){
+        MultiDoku md = SudokuFactory.createBasicXShapedMultidoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+        SudokuPrinter.printMultiDoku(RenderableMultidoku.fromMultidoku(md), Symbols.Numbers, 3, 3);
+    }
+
+    public static void filledTest(){
+        MultiDoku md = SudokuFactory.createBasicXShapedMultidoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+        new RandomSolver().solve(md);
+        SudokuPrinter.printMultiDoku(RenderableMultidoku.fromMultidoku(md), Symbols.Numbers, 3, 3);
+    }
+
     public static void main(String[] args) {
-        System.out.println(new Main().getGreeting());
-        int blockWidth = 3;
-        int blockHeight = 3;
-        var sudoku = SudokuFactory.createBasicEmptyRectangleSudoku(blockWidth, blockHeight);
-        SudokuPrinter.printRectangleSudoku(sudoku.getSubGrid(0), blockWidth , blockHeight);
+        ConsoleInterface console = new ConsoleInterface();
+        /*
+        voidTest();
+        filledTest();
+        filledTest();
+        */
+        console.welcome();
     }
 }

app/src/main/java/sudoku/MultiDoku.java

@@ -1,45 +0,0 @@
-package sudoku;
-
-import sudoku.constraint.IConstraint;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * @class MultiDoku
- * @brief Représente une grille de Multidoku.
- *        Une grille de sudoku est un multidoku avec un seul sous-sudoku
- */
-public class MultiDoku {
-
-	private final List<Sudoku> subGrids;
-
-	public MultiDoku(List<Sudoku> subGrids) {
-		this.subGrids = subGrids;
-	}
-
-	public int getNbSubGrids(){
-		return subGrids.size();
-	}
-
-	public Sudoku getSubGrid(int i){
-		return subGrids.get(i);
-	}
-
-	public boolean isValid(List<IConstraint> constraints){
-		for (Sudoku sudoku : subGrids){
-			if (!sudoku.isValid(constraints))
-				return false;
-		}
-		return true;
-	}
-
-	public List<MutableCell> getMutableCells(){
-		List<MutableCell> mutableCells = new ArrayList<>();
-		for (Sudoku sudoku : subGrids){
-			mutableCells.addAll(sudoku.getMutableCells());
-		}
-		return mutableCells;
-	}
-
-}

app/src/main/java/sudoku/MutableCell.java

@@ -1,37 +0,0 @@
-package sudoku;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class MutableCell extends Cell{
-
-	private final List<Integer> hintsSymbolIndex;
-
-	public MutableCell() {
-		super();
-		this.hintsSymbolIndex = new ArrayList<>();
-	}
-
-	public MutableCell(int symboleIndex) {
-		super(symboleIndex);
-		this.hintsSymbolIndex = new ArrayList<>();
-	}
-
-	public void setSymboleIndex(int symboleIndex) {
-		this.symboleIndex = symboleIndex;
-	}
-
-	public void clear() {
-		setSymboleIndex(NOSYMBOLE);
-	}
-
-	public void clear(int indexSymbol) {
-		hintsSymbolIndex.remove(indexSymbol);
-		this.clear();
-	}
-
-	public List<Integer> getHints() {
-		return this.hintsSymbolIndex;
-	}
-
-}

app/src/main/java/sudoku/Sudoku.java

@@ -1,52 +0,0 @@
-package sudoku;
-
-import sudoku.constraint.IConstraint;
-
-import javax.swing.*;
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * @class Sudoku
- * @brief Représente une grille de sudoku avec N symboles
- */
-public class Sudoku {
-
-	private final List<Block> blocks;
-	private final List<Cell> cells;
-
-	public Sudoku(List<Cell> cells, List<Block> blocks) {
-		this.cells = cells;
-		this.blocks = blocks;
-	}
-
-	public Cell getCell(int x, int y) {
-		int index = y * getSize() + x;
-		assert(index < getSize() * getSize());
-		return this.cells.get(index);
-	}
-
-	public Cell getCell(int i) {
-		return this.cells.get(i);
-	}
-
-	public int getSize() {
-		return this.blocks.size();
-	}
-
-	public Boolean isValid(List<IConstraint> constraints) {
-		//not implemented
-		//for eachcase check contraintes
-		throw new Error("Function isValid() not implemented");
-	}
-
-	public List<MutableCell> getMutableCells() {
-		List<MutableCell> mutableCells = new ArrayList<>();
-		for (Cell cell : this.cells) {
-			if (cell instanceof MutableCell){
-				mutableCells.add((MutableCell) cell);
-			}
-		}
-		return mutableCells;
-	}
-}

app/src/main/java/sudoku/SudokuFactory.java

@@ -1,50 +0,0 @@
-package sudoku;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class SudokuFactory {
-
-	private static List<Cell> initCells(int size) {
-		List<Cell> cells = new ArrayList<>(size * size);
-		for (int i = 0; i < size * size; i++) {
-			cells.add(new MutableCell());
-		}
-		return cells;
-	}
-
-	private static List<Block> initRectangleBlocs(List<Cell> cells, int width, int height) {
-		List<Block> blocs = new ArrayList<>();
-		int size = width * height;
-		for (int i = 0; i < size; i++) {
-			Block newBlock = new Block();
-			int blockX = i % height;
-			int blockY = i / height;
-			for (int y = 0; y < height; y++) {
-				for (int x = 0; x < width; x++) {
-					int index = ((y + blockY * height) * size + (x + blockX * width));
-					Cell blockCell = cells.get(index);
-					blockCell.setBlock(newBlock);
-					newBlock.addCell(blockCell);
-				}
-			}
-			blocs.add(newBlock);
-		}
-		return blocs;
-	}
-
-	public static MultiDoku createBasicEmptyRectangleSudoku(int width, int height) {
-		int symbolCount = width * height;
-		List<Cell> cases = initCells(symbolCount);
-		List<Block> blocs = initRectangleBlocs(cases, width, height);
-		Sudoku s = new Sudoku(cases, blocs);
-		List<Sudoku> ss = new ArrayList<>();
-		ss.add(s);
-		return new MultiDoku(ss);
-	}
-
-	public static MultiDoku createBasicEmptySquareSudoku(int size) {
-		return createBasicEmptyRectangleSudoku(size, size);
-	}
-
-}

app/src/main/java/sudoku/constraint/BlockConstraint.java

@@ -1,15 +1,14 @@
 package sudoku.constraint;
 
-import sudoku.Block;
-import sudoku.Cell;
-import sudoku.Sudoku;
+import sudoku.structure.Block;
+import sudoku.structure.Sudoku;
 
 public class BlockConstraint implements IConstraint{
 
 	@Override
 	public boolean canBePlaced(final Sudoku s, int x, int y, int newSymbolIndex) {
-		Block bloc = s.getCell(x, y).getBlock();
-		return !bloc.getCells().contains(new Cell(newSymbolIndex) {});
+		Block block = s.getCell(x, y).getBlock();
+		return !block.containsSymbol(newSymbolIndex);
 	}
 
 }

app/src/main/java/sudoku/constraint/ColumnConstraint.java

@@ -1,16 +1,19 @@
 package sudoku.constraint;
 
-import sudoku.Sudoku;
+import sudoku.structure.Cell;
+import sudoku.structure.Sudoku;
 
 public class ColumnConstraint implements IConstraint {
 
 	@Override
 	public boolean canBePlaced(final Sudoku s, int x, int y, int newSymbolIndex) {
 		for (int i = 0; i < s.getSize(); i++) {
-			if (s.getCell(x, newSymbolIndex).getSymboleIndex() == newSymbolIndex)
+			Cell cell = s.getCell(x, i);
+			int symbol = cell.getSymbolIndex();
+			if (symbol == newSymbolIndex) {
 				return false;
+			}
 		}
 		return true;
 	}
-
 }

app/src/main/java/sudoku/constraint/Constraint.java

@@ -0,0 +1,52 @@
+package sudoku.constraint;
+
+import java.util.List;
+
+import sudoku.structure.Sudoku;
+
+public enum Constraint {
+
+	Block("Bloc", new BlockConstraint()),
+	Column("Colonne", new ColumnConstraint()),
+	Line("Ligne", new LineConstraint()),
+	Diagonal("Diagonale", new DiagonalConstraint());
+
+	String displayName;
+	IConstraint constraint;
+
+	private Constraint(String displayName, IConstraint contraint) {
+		this.constraint = contraint;
+		this.displayName = displayName;
+	}
+
+	public boolean canBePlaced(Sudoku s, int x, int y, int newValue) {
+		return getConstraint().canBePlaced(s, x, y, newValue);
+	}
+
+	public List<Integer> getPossibleSymbols(final Sudoku s, int x, int y) {
+		return getConstraint().getPossibleSymbols(s, x, y);
+	}
+
+	public String getDisplayName() {
+		return displayName;
+	}
+
+	public IConstraint getConstraint() {
+		return constraint;
+	}
+
+	private static final String[] constraintNames;
+
+	static {
+		Constraint[] cons = Constraint.values();
+		constraintNames = new String[cons.length];
+		for (int i = 0; i < cons.length; i++) {
+			constraintNames[i] = cons[i].getDisplayName();
+		}
+	}
+
+	public static String[] getConstraintNames() {
+		return constraintNames;
+	}
+
+}

app/src/main/java/sudoku/constraint/DiagonalConstraint.java

@@ -0,0 +1,24 @@
+package sudoku.constraint;
+
+import sudoku.structure.Sudoku;
+
+public class DiagonalConstraint implements IConstraint {
+
+	@Override
+	public boolean canBePlaced(Sudoku s, int x, int y, int newSymbolIndex) {
+		if (x == y) {
+			for (int i = 0; i < s.getSize(); i++) {
+				if (s.getCell(i, i).getSymbolIndex() == newSymbolIndex)
+					return false;
+			}
+		} else if (s.getSize() - x == y) {
+			for (int i = 0; i < s.getSize(); i++) {
+				if (s.getCell(s.getSize() - i - 1, i).getSymbolIndex() == newSymbolIndex)
+					return false;
+			}
+		}
+		// not in diagonal
+		return true;
+	}
+
+}

app/src/main/java/sudoku/constraint/IConstraint.java

@@ -3,7 +3,7 @@ package sudoku.constraint;
 import java.util.ArrayList;
 import java.util.List;
 
-import sudoku.Sudoku;
+import sudoku.structure.Sudoku;
 
 public interface IConstraint {
 

app/src/main/java/sudoku/constraint/LineConstraint.java

@@ -1,13 +1,13 @@
 package sudoku.constraint;
 
-import sudoku.Sudoku;
+import sudoku.structure.Sudoku;
 
 public class LineConstraint implements IConstraint {
 
 	@Override
 	public boolean canBePlaced(final Sudoku s, int x, int y, int newSymbolIndex) {
 		for (int i = 0; i < s.getSize(); i++) {
-			if (s.getCell(newSymbolIndex, y).getSymboleIndex() == newSymbolIndex)
+			if (s.getCell(i, y).getSymbolIndex() == newSymbolIndex)
 				return false;
 		}
 		return true;

app/src/main/java/sudoku/io/ConsoleInterface.java

@@ -0,0 +1,134 @@
+package sudoku.io;
+
+import gui.RenderableMultidoku;
+import gui.Symbols;
+import sudoku.constraint.*;
+import sudoku.solver.RandomSolver;
+import sudoku.structure.Difficulty;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+public class ConsoleInterface {
+    public Scanner reader = new Scanner(System.in);
+
+    public void welcome(){
+        System.out.println("Welcome to our Sudoku Solver!");
+        System.out.println("This is the project of Melvyn Bauvent, Lilas Grenier and Simon Priblyski.");
+        start();
+    }
+
+    public void start(){
+        System.out.println("First of all, you need to tell me the size of the sudoku you want to generate.");
+        int width = getBlockWidth();
+        int height = getBlockHeight();
+        System.out.println("Your sudoku will have blocks of a " + width + " x " + height + " format.");
+        int numberOfSymbols = width * height;
+        System.out.println("Would you like to pick the " + numberOfSymbols + " symbols from the sudoku? (y/n, default 'no' will use numbers)" );
+        List<String> listSymbols = new ArrayList<>();
+        if(reader.next().equalsIgnoreCase("y")){
+            pickSymbols(listSymbols, numberOfSymbols);
+        }
+        else {
+            listSymbols = Symbols.Numbers.getSymbols();
+        }
+        List<Constraint> listConstraints = getListConstraints();
+        System.out.println("Now that we have the size of our sudoku, would you rather have a single grid ('one', default), " +
+                "or a a multidoku composed of 5 subgrids ('multi') ?");
+        MultiDoku doku;
+        if (reader.next().equalsIgnoreCase("multi")) {
+            doku = SudokuFactory.createBasicXShapedMultidoku(width, height, listConstraints);
+        }
+        else {
+            doku = SudokuFactory.createBasicEmptyRectangleDoku(width, height, listConstraints);
+        }
+        RenderableMultidoku rm = RenderableMultidoku.fromMultidoku(doku);
+        System.out.println("Your sudoku will look like this:");
+        SudokuPrinter.printMultiDoku(rm, listSymbols, width, height);
+        System.out.println("We now will fill this sudoku.");
+        System.out.println("What level of difficulty would you like? ('very easy', 'easy', 'medium' (default), 'hard', 'full' (sudoku fully completed))");
+        String difficulty = reader.next().toLowerCase();
+        if (difficulty.equals("full")) {
+            generateFullDoku(doku);
+        }
+        else {
+            generatePartialDoku(doku, difficulty);
+        }
+        System.out.println("Here's your sudoku !");
+        SudokuPrinter.printMultiDoku(rm, listSymbols, width, height);
+    }
+
+    public int getBlockWidth() {
+        System.out.println("Width of a block: ");
+        int widthBlock = reader.nextInt();
+        checkValidSize(widthBlock);
+        while (!checkValidSize(widthBlock)) {
+            System.out.println("That is not a valid width for a block. Try again:");
+            widthBlock = reader.nextInt();
+        }
+        System.out.println("You have chose a width of " + widthBlock + ".");
+        return widthBlock;
+    }
+
+    public int getBlockHeight() {
+        System.out.println("Height of a block: ");
+        int heightBlock = reader.nextInt();
+        checkValidSize(heightBlock);
+        while (!checkValidSize(heightBlock)) {
+            System.out.println("That is not a valid height for a block. Try again:");
+            heightBlock = reader.nextInt();
+        }
+        System.out.println("You have chose a height of " + heightBlock + ".");
+        return heightBlock;
+    }
+
+    private Boolean checkValidSize(int size) {
+        return (size > 0);
+    }
+
+    private void pickSymbols(List<String> listSymbols, int numberOfSymbols) {
+        System.out.println("You have chosen to pick your own symbols.");
+        for (int i = 0; i < numberOfSymbols; i++) {
+            System.out.println("Choose for the symbol number " + i + ": ");
+            String newSymbol = reader.next();
+            while (listSymbols.contains(newSymbol)) {
+                System.out.println("This symbol has already been given. Try again:");
+                newSymbol = reader.next();
+            }
+            listSymbols.add(newSymbol);
+        }
+        System.out.println("You chose the symbols: " + listSymbols.toString());
+    }
+
+    private List<Constraint> getListConstraints() {
+        List<Constraint> listConstraints = SudokuFactory.DEFAULT_CONSTRAINTS;
+        System.out.println("The sudoku have constraints of blocks, lines and columns. Would you like to add the diagonal constraints ? (y/n, default 'no')");
+        if(reader.next().equalsIgnoreCase("y")){
+            listConstraints.add(Constraint.Diagonal);
+        }
+        return listConstraints;
+    }
+
+    private void generatePartialDoku(MultiDoku doku, String difficultyName) {
+        Difficulty difficulty;
+        switch (difficultyName){
+            case "very easy": difficulty = Difficulty.VeryEasy;
+            case "easy": difficulty = Difficulty.Easy;
+            case "hard": difficulty = Difficulty.Hard;
+            default: difficulty = Difficulty.Medium;
+        }
+        try {
+            SudokuFactory.fillDoku(doku, difficulty);
+        } catch (Exception e) {
+            System.out.println("There seems to be a problem with those settings. Let's start again.");
+        }
+    }
+
+    private void generateFullDoku(MultiDoku doku) {
+        new RandomSolver().solve(doku);
+    }
+
+}

app/src/main/java/sudoku/io/SudokuFile.java

@@ -0,0 +1,7 @@
+package sudoku.io;
+
+public class SudokuFile {
+
+	
+
+}

app/src/main/java/sudoku/io/SudokuPrinter.java

@@ -1,23 +1,123 @@
 package sudoku.io;
 
-import sudoku.Sudoku;
+import gui.RenderableMultidoku;
+import gui.Symbols;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+import java.util.List;
 
 public class SudokuPrinter {
+	public static final String ANSI_RESET = "\u001B[0m";
+	public static final String ANSI_RED = "\u001B[31m";
+	public static final String ANSI_GREEN = "\u001B[32m";
+	public static final String ANSI_YELLOW = "\u001B[33m";
+	public static final String ANSI_BLUE = "\u001B[34m";
+	public static final String ANSI_PURPLE = "\u001B[35m";
+	public static final String ANSI_CYAN = "\u001B[36m";
 
-	public static void printRectangleSudoku(final Sudoku s, int blockWidth, int blockHeight) {
+	public static void printRectangleSudoku(final Sudoku s, int blockWidth, int blockHeight, Symbols symbols) {
+		printRectangleSudoku(s, blockWidth, blockHeight, symbols.getSymbols());
+	}
+
+	public static void printRectangleSudoku(final Sudoku s, int blockWidth, int blockHeight, List<String> listSymbols){
 		for (int y = 0; y < s.getSize(); y++) {
-			if (y % blockHeight == 0 && y > 0) {
-				System.out.println("");
+		if (y % blockHeight == 0 && y > 0) {
+			System.out.println();
+		}
+		StringBuilder line = new StringBuilder("[ ");
+		for (int x = 0; x < s.getSize(); x++) {
+			Cell c = s.getCell(x, y);
+			if (c.getSymbolIndex() == Cell.NOSYMBOL) {
+				line.append("  ");
 			}
-			String line = "[ ";
-			for (int x = 0; x < s.getSize(); x++) {
-				line += (s.getCell(x, y).getSymboleIndex() + 1) + " ";
-				if (x % blockWidth == blockWidth - 1 && x != blockWidth * blockHeight - 1) {
-					line += "| ";
+			else {
+				line.append(listSymbols.get(c.getSymbolIndex())).append(" ");
+			}
+			if (x % blockWidth == blockWidth - 1 && x != blockWidth * blockHeight - 1) {
+				line.append("| ");
+			}
+		}
+		line.append("]");
+		System.out.println(line);
+	}
+}
+
+	public static void printMultiDoku(final RenderableMultidoku rm, Symbols symbols, int blockWidth, int blockHeight) {
+		printMultiDoku(rm, symbols.getSymbols(), blockWidth, blockHeight);
+	}
+
+	public static void printMultiDoku(final RenderableMultidoku rm, List<String> listSymbols, int blockWidth, int blockHeight) {
+		StringBuilder line = new StringBuilder("\n");
+		int nBlockInWidth = rm.getWidth() / blockWidth;
+		for (int y = 0; y < rm.getHeight(); y++) {
+			if (y % blockHeight == 0) {
+                line.append("__".repeat(Math.max(0, rm.getWidth()+nBlockInWidth))).append("_\n");
+			}
+			line.append("[ ");
+			for (int x = 0; x < rm.getWidth(); x++) {
+				if (x % blockWidth == 0 && x > 0) {
+					line.append("| ");
+				}
+				Cell cell = rm.getCell(x, y);
+				if (cell != null) {
+					if (cell.getSymbolIndex() == Cell.NOSYMBOL) {
+						line.append("- ");
+					}
+					else {
+						line.append(listSymbols.get(cell.getSymbolIndex())).append(" ");
+					}
+				}
+				else {
+					line.append("  ");
 				}
 			}
-			line += "]";
-			System.out.println(line);
+			line.append("]\n");
+		}
+		line.append("__".repeat(Math.max(0, rm.getWidth()+nBlockInWidth))).append("_\n");
+		System.out.println(line);
+	}
+
+	public static String toStringRectangleSudoku(final Sudoku s, int blockWidth, int blockHeight, Symbols symbols){
+		return toStringRectangleSudoku(s, blockWidth, blockHeight, symbols.getSymbols());
+	}
+
+	public static String toStringRectangleSudoku(final Sudoku s, int blockWidth, int blockHeight, List<String> listSymbols) {
+		StringBuilder result = new StringBuilder();
+		for (int y = 0; y < s.getSize(); y++) {
+			// Ajouter une ligne vide entre les blocs horizontaux
+			if (y % blockHeight == 0 && y > 0) {
+				result.append("\n");
+			}
+			StringBuilder line = new StringBuilder("[ ");
+			for (int x = 0; x < s.getSize(); x++) {
+				// Ajouter la valeur de la cellule
+				Cell cell = s.getCell(x, y);
+				if (cell.getSymbolIndex() == Cell.NOSYMBOL) {
+					line.append("  ");
+				}
+				else {
+					line.append(listSymbols.get(cell.getSymbolIndex())).append(" ");
+				}
+
+				// Ajouter un séparateur vertical entre les blocs
+				if (x % blockWidth == blockWidth - 1 && x != s.getSize() - 1) {
+					line.append("| ");
+				}
+			}
+			line.append("]");
+			result.append(line).append("\n");
+		}
+		return result.toString();
+	}
+
+	public static void printMultiDoku(final MultiDoku doku, int blockWidth, int blockHeight, Symbols symbols){
+		if (doku.getNbSubGrids()==1) {
+			printRectangleSudoku(doku.getSubGrid(0), blockWidth, blockHeight, symbols);
+		}
+		else {
+			printMultiDoku(RenderableMultidoku.fromMultidoku(doku), symbols, blockWidth, blockHeight);
 		}
 	}
 }

app/src/main/java/sudoku/io/SudokuSave.java

@@ -0,0 +1,15 @@
+package sudoku.io;
+
+public class SudokuSave {
+
+	public static enum AlgoResolution {
+		Backtracking,
+		NoBacktring
+	}
+
+	// private final MultiDoku sudoku;
+	// private final AlgoResolution resolution;
+
+	
+
+}

app/src/main/java/sudoku/io/SudokuSerializer.java

@@ -0,0 +1,248 @@
+package sudoku.io;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.json.JSONArray;
+import org.json.JSONObject;
+
+import sudoku.constraint.Constraint;
+import sudoku.structure.Block;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class SudokuSerializer {
+
+	public static JSONObject serializeSudoku(final MultiDoku multidoku) {
+		List<Cell> cellIds = new ArrayList<>();
+		List<Block> blockIds = new ArrayList<>();
+
+		JSONObject jsonRoot = new JSONObject();
+		JSONArray jsonCells = new JSONArray();
+		JSONArray jsonBlocks = new JSONArray();
+		JSONArray jsonSudokus = new JSONArray(multidoku.getNbSubGrids());
+
+		for (int i = 0; i < multidoku.getNbSubGrids(); i++) {
+			Sudoku sudoku = multidoku.getSubGrid(i);
+
+			// init cells
+			for (Cell cell : sudoku.getCells()) {
+				if (cellIds.contains(cell))
+					continue;
+
+				cellIds.add(cell);
+
+				Block block = cell.getBlock();
+				if (!blockIds.contains(block)) {
+					blockIds.add(block);
+				}
+
+				int blockID = blockIds.indexOf(block);
+				assert(blockID >= 0);
+				int symbolIndex = cell.getSymbolIndex();
+
+				JSONObject cellJsonObject = new JSONObject();
+				cellJsonObject.put("blockID", blockID);
+				cellJsonObject.put("symbolIndex", symbolIndex);
+				if (!cell.isMutable()) {
+					cellJsonObject.put("immutable", true);
+				}
+				jsonCells.put(cellJsonObject);
+			}
+
+		}
+
+		// init blocks
+
+		for (Block blockId : blockIds) {
+			JSONObject blockJsonObject = new JSONObject();
+			JSONArray cellsJsonArray = new JSONArray();
+			for (Cell cell : blockId.getCells()) {
+				int cellID = cellIds.indexOf(cell);
+				assert (cellID >= 0);
+				cellsJsonArray.put(cellID);
+			}
+			blockJsonObject.put("cellIDs", cellsJsonArray);
+			jsonBlocks.put(blockJsonObject);
+		}
+
+		for (int i = 0; i < multidoku.getNbSubGrids(); i++) {
+			// serialise sub grid
+			JSONObject jsonSudoku = new JSONObject();
+			JSONArray cellsJsonArray = new JSONArray();
+			JSONArray blocksJsonArray = new JSONArray();
+			JSONArray constraintsJsonArray = new JSONArray();
+
+			Sudoku sudoku = multidoku.getSubGrid(i);
+
+			// serialize cells
+
+			for (Cell cell : sudoku.getCells()) {
+				int cellID = cellIds.indexOf(cell);
+				assert (cellID >= 0);
+				cellsJsonArray.put(cellID);
+			}
+
+			// serialize blocks
+
+			for (Block block : sudoku.getBlocks()) {
+				int blockID = blockIds.indexOf(block);
+				assert (blockID >= 0);
+				blocksJsonArray.put(blockID);
+			}
+
+			// serialize constraints
+
+			for (Constraint cons : sudoku.getConstraints()) {
+				constraintsJsonArray.put(cons.ordinal());
+			}
+
+			jsonSudoku.put("constraints", constraintsJsonArray);
+			jsonSudoku.put("cells", cellsJsonArray);
+			jsonSudoku.put("blocks", blocksJsonArray);
+			jsonSudoku.put("blockWidth", sudoku.getBlockWidth());
+			jsonSudokus.put(i, jsonSudoku);
+		}
+
+		jsonRoot.put("multidoku", jsonSudokus);
+		jsonRoot.put("cells", jsonCells);
+		jsonRoot.put("blocks", jsonBlocks);
+
+		return jsonRoot;
+	}
+
+	/**
+	 * Save a serialized MultiDoku in a JSON file.
+	 * 
+	 * @param doku MultiDoku, MultiDoku to save.
+	 * @return String, the path of the save.
+	 */
+	public static String saveMultiDoku(final MultiDoku doku) {
+
+		JSONObject jsonRoot = serializeSudoku(doku);
+
+		File f = new File("save", "save.json");
+		int i = 0;
+
+		while (f.exists()) {
+			String newName = "save-" + ++i + ".json";
+			f = new File("save", newName);
+		}
+
+		try (FileWriter file = new FileWriter(f)) {
+			file.write(jsonRoot.toString(3));
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+		return f.getAbsolutePath();
+	}
+
+	/**
+	 * Get a MultiDoku from a pre-existing json save file.
+	 * 
+	 * @param numberSave int, number of the save file to open.
+	 * @return MultiDoku, MultoDoku contained in the file.
+	 * @throws Exception when the given save file does not exist.
+	 */
+	public static MultiDoku getSavedMultiDoku(int numberSave) throws Exception {
+		String fileName;
+		if (numberSave < 1) {
+			fileName = "save.json";
+		} else {
+			fileName = "save-" + numberSave + ".json";
+		}
+
+		File f = new File("save", fileName);
+		String fileContent;
+
+		if (!f.exists()) {
+			throw new Exception("This save does not exist.");
+		} else {
+			fileContent = new String(Files.readAllBytes(Paths.get("save/" + fileName)));
+			return deserializeSudoku(fileContent);
+		}
+	}
+
+	public static MultiDoku deserializeSudoku(final String json) {
+		JSONObject jsonRoot = new JSONObject(json);
+		return deserializeSudoku(jsonRoot);
+	}
+
+	public static MultiDoku deserializeSudoku(final JSONObject jsonObject) {
+
+		List<Cell> cells = new ArrayList<>();
+		List<Block> blocks = new ArrayList<>();
+		List<Sudoku> sudokus = new ArrayList<>();
+
+		// init cells
+		JSONArray cellsJson = jsonObject.getJSONArray("cells");
+		for (int i = 0; i < cellsJson.length(); i++) {
+			JSONObject entry = cellsJson.getJSONObject(i);
+			int symbolIndex = entry.getInt("symbolIndex");
+			if (entry.has("immutable")) {
+				cells.add(new Cell(symbolIndex, false));
+			} else {
+				cells.add(new Cell(symbolIndex));
+			}
+		}
+
+		// init blocks
+		JSONArray blocksJson = jsonObject.getJSONArray("blocks");
+		for (int i = 0; i < blocksJson.length(); i++) {
+			JSONObject entry = blocksJson.getJSONObject(i);
+			JSONArray cellIds = entry.getJSONArray("cellIDs");
+			List<Cell> blockCells = new ArrayList<>();
+			Block newBlock = new Block(blockCells);
+			for (int j = 0; j < cellIds.length(); j++) {
+				int cellID = cellIds.getInt(j);
+				Cell blockCell = cells.get(cellID);
+				blockCell.setBlock(newBlock);
+				blockCells.add(blockCell);
+			}
+			blocks.add(newBlock);
+		}
+
+		JSONArray multidokuJsonObject = jsonObject.getJSONArray("multidoku");
+		for (int i = 0; i < multidokuJsonObject.length(); i++) {
+			JSONObject sudokuJsonObject = multidokuJsonObject.getJSONObject(i);
+			JSONArray sudokuCellsJsonArray = sudokuJsonObject.getJSONArray("cells");
+			JSONArray sudokuBlocksJsonArray = sudokuJsonObject.getJSONArray("blocks");
+			JSONArray sudokuConstraintsJsonArray = sudokuJsonObject.getJSONArray("constraints");
+
+			List<Cell> sudokuCells = new ArrayList<>();
+			List<Block> sudokuBlocks = new ArrayList<>();
+			List<Constraint> sudokuConstraints = new ArrayList<>();
+
+			for (int j = 0; j < sudokuCellsJsonArray.length(); j++) {
+				int cellID = sudokuCellsJsonArray.getInt(j);
+				sudokuCells.add(cells.get(cellID));
+			}
+
+			for (int j = 0; j < sudokuBlocksJsonArray.length(); j++) {
+				int blockID = sudokuBlocksJsonArray.getInt(j);
+				sudokuBlocks.add(blocks.get(blockID));
+			}
+
+			for (int j = 0; j < sudokuConstraintsJsonArray.length(); j++) {
+				int constraintID = sudokuConstraintsJsonArray.getInt(j);
+				sudokuConstraints.add(Constraint.values()[constraintID]);
+			}
+
+			Sudoku s = new Sudoku(sudokuCells, sudokuBlocks, sudokuConstraints);
+			s.setBlockWidth(sudokuJsonObject.getInt("blockWidth"));
+			for (Block block : s.getBlocks()) {
+				block.getSudokus().add(s);
+			}
+			sudokus.add(s);
+		}
+
+		return new MultiDoku(sudokus);
+	}
+
+}

app/src/main/java/sudoku/solver/BacktrackingSolver.java

@@ -0,0 +1,49 @@
+package sudoku.solver;
+
+import java.util.List;
+import java.util.concurrent.CancellationException;
+
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+
+public class BacktrackingSolver implements Solver {
+
+	/**
+	 * Résout le MultiDoku passé en paramètre, avec backtracking.
+	 *
+	 * @param doku MultiDoku, MultiDoku à résoudre.
+	 * @return boolean, valant true si le MultiDoku est résolu, false sinon.
+	 */
+	@Override
+	public boolean solve(MultiDoku doku) {
+		if (Thread.interrupted())
+			throw new CancellationException("User wants to stop the solver");
+
+		if (doku.isSolved()) {
+			return true;
+		}
+
+		Cell cellToFill = doku.getFirstEmptyCell();
+		if (cellToFill == null) {
+			return false;
+		}
+
+		List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+		if (possibleSymbols.isEmpty()) {
+			return false;
+		}
+
+		for (int symbol : possibleSymbols) {
+
+			cellToFill.setSymbolIndex(symbol);
+			if (this.solve(doku)) {
+				return true;
+			} else {
+				cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+			}
+
+		}
+		return false;
+	}
+
+}

app/src/main/java/sudoku/solver/HumanSolver.java

@@ -0,0 +1,57 @@
+package sudoku.solver;
+
+import java.util.List;
+import java.util.concurrent.CancellationException;
+import java.util.logging.Level;
+
+import gui.Symbols;
+import sudoku.io.SudokuPrinter;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class HumanSolver implements Solver {
+
+	/**
+	 * Résout le MultiDoku passé en paramètre, avec règles de déduction.
+	 *
+	 * @param doku MultiDoku, MultiDoku à résoudre.
+	 * @return boolean, valant true si le MultiDoku est résolu, false sinon.
+	 */
+	@Override
+	public boolean solve(MultiDoku doku) {
+		if (Thread.interrupted())
+			throw new CancellationException("User wants to stop the solver");
+
+		Sudoku sudoku = doku.getSubGrid(0);
+		logger.log(Level.FINE,
+				'\n' + SudokuPrinter.toStringRectangleSudoku(sudoku,
+						sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getBlockWidth(),
+						sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getSize() / sudoku.getBlockWidth(),
+				Symbols.Numbers));
+
+		if (doku.isSolved()) {
+			return true;
+		}
+
+		List<Cell> cellsToFill = doku.getEmptyCells();
+		if (cellsToFill.isEmpty()) {
+			return false;
+		}
+
+		for (Cell cellToFill : cellsToFill) {
+
+			List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+			if (possibleSymbols.size() != 1) {
+				continue;
+			}
+
+			cellToFill.setSymbolIndex(possibleSymbols.getFirst());
+
+			return this.solve(doku);
+		}
+
+		return doku.isSolved();
+	}
+
+}

app/src/main/java/sudoku/solver/MixedSolver.java

@@ -0,0 +1,82 @@
+package sudoku.solver;
+
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.CancellationException;
+import java.util.logging.Level;
+
+import gui.Symbols;
+import sudoku.io.SudokuPrinter;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class MixedSolver implements Solver{
+
+	/**
+     * Résout le MultiDoku passé en paramètre, avec règles de déduction et
+     * backtracking.
+     *
+     * @param doku MultiDoku, MultiDoku à résoudre.
+     * @return boolean, valant true si le MultiDoku est résolu, false sinon.
+     */
+	@Override
+    public boolean solve(MultiDoku doku) {
+        Random rand = new Random();
+
+        if (Thread.interrupted()) {
+            throw new CancellationException("User wants to stop the solver");
+        }
+
+        Sudoku sudoku = doku.getSubGrid(0);
+        logger.log(Level.FINE,
+                '\n' + SudokuPrinter.toStringRectangleSudoku(
+                        sudoku,
+                        sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getBlockWidth(),
+                        sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getSize() / sudoku.getBlockWidth(),
+                Symbols.Numbers));
+
+        if (doku.isSolved()) {
+            return true;
+        }
+
+        List<Cell> cellsToFill = doku.getEmptyCells();
+        if (cellsToFill.isEmpty()) {
+            return false;
+        }
+
+        // Règles de déduction
+        for (Cell cellToFill : cellsToFill) {
+
+            List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+            if (possibleSymbols.size() != 1) {
+                continue;
+            }
+
+            cellToFill.setSymbolIndex(possibleSymbols.getFirst());
+
+            return this.solve(doku);
+        }
+
+        // Si ça ne marche pas
+        // On fait du backtracking
+        Cell cellToFill = doku.getRandomEmptyCell(rand);
+        List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+
+        while (!possibleSymbols.isEmpty()) {
+            int nextPossibleSymbolIndex = rand.nextInt(possibleSymbols.size());
+            int nextSymbol = possibleSymbols.get(nextPossibleSymbolIndex);
+
+            cellToFill.setSymbolIndex(nextSymbol);
+            if (this.solve(doku)) {
+                return true;
+            }
+
+            cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+            possibleSymbols.remove(nextPossibleSymbolIndex);
+        }
+
+        return false;
+    }
+
+}

app/src/main/java/sudoku/solver/RandomSolver.java

@@ -0,0 +1,65 @@
+package sudoku.solver;
+
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.CancellationException;
+import java.util.logging.Level;
+
+import gui.Symbols;
+import sudoku.io.SudokuPrinter;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+public class RandomSolver implements Solver {
+
+	/**
+     * Résout, si possible, le multidoku passé en paramètre
+     * en testant toutes les possibilités, de manière aléatoire, avec un algorithme
+     * de backtracking.
+     *
+     * @param doku Multidoku, à résoudre
+     * @param rand Random, pour tester aléatoirement les symboles
+     * @return boolean, true s'il est résolu ou false s'il ne l'est pas.
+     */
+	@Override
+    public boolean solve(MultiDoku doku) {
+        Random rand = new Random();
+
+        if (Thread.interrupted())
+            throw new CancellationException("User wants to stop the solver");
+
+        Sudoku sudoku = doku.getSubGrid(0);
+        logger.log(Level.FINE,
+                '\n' + SudokuPrinter.toStringRectangleSudoku(sudoku,
+                        sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getBlockWidth(),
+                        sudoku.getBlockWidth() == 0 ? sudoku.getSize() : sudoku.getSize() / sudoku.getBlockWidth(),
+                        Symbols.Numbers));
+
+        if (doku.isSolved()) {
+            return true;
+        }
+
+        Cell cellToFill = doku.getFirstEmptyCell();
+        if (cellToFill == null) {
+            return false;
+        }
+
+        List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+
+        while (!possibleSymbols.isEmpty()) {
+            int nextPossibleSymbolIndex = rand.nextInt(possibleSymbols.size());
+            int nextSymbol = possibleSymbols.get(nextPossibleSymbolIndex);
+
+            cellToFill.setSymbolIndex(nextSymbol);
+            if (this.solve(doku)) {
+                return true;
+            }
+            cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+            possibleSymbols.remove(nextPossibleSymbolIndex);
+
+        }
+        return false;
+    }
+
+}

app/src/main/java/sudoku/solver/Solver.java

@@ -1,39 +1,47 @@
 package sudoku.solver;
 
-import sudoku.Cell;
-import sudoku.MultiDoku;
-import sudoku.MutableCell;
-import sudoku.Sudoku;
-import sudoku.constraint.IConstraint;
-
-import java.util.ArrayList;
 import java.util.List;
-import java.util.Random;
+import java.util.logging.Logger;
 
-public class Solver {
-    Caretaker stack;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
 
-    public Solver() {
-    }
+public interface Solver {
 
-    public MultiDoku solve(MultiDoku doku, List<IConstraint> constraints) throws Exception {
-        if (!doku.isValid(constraints)) {
-            throw new Exception("Invalid doku");
+	/**
+     * Log du Solver, qui garde trace des actions réalisées.
+     */
+    public static final Logger logger = Logger.getLogger("SolverLogger");
+
+	boolean solve(MultiDoku doku);
+
+	 /**
+     * Compte le nombre de solutions possibles au MultiDoku passé en paramètres.
+     *
+     * @param doku MultiDoku, MultiDoku dont on veut le nombre de solutions.
+     * @return int, nombre de solutions possibles.
+     */
+    default int countSolution(MultiDoku doku) {
+        int result = 0;
+
+        if (doku.isSolved()) {
+            return 1;
         }
-        List<MutableCell> allMutableCells = doku.getMutableCells();
-        List<MutableCell> remainingCellsToCheck = new ArrayList<>(allMutableCells);
-        Random rand = new Random();
-        while (!remainingCellsToCheck.isEmpty()) {
-            int indexCurrentCell = rand.nextInt(remainingCellsToCheck.size());
-            MutableCell currentCell = remainingCellsToCheck.get(indexCurrentCell);
-            if (currentCell.getHints().isEmpty()){
-                MutableCell modify = allMutableCells.get(stack.undo());
-                modify.clear(modify.getSymboleIndex());
+
+        Cell cellToFill = doku.getFirstEmptyCell();
+        assert (cellToFill != null);
+
+        List<Integer> possibleSymbols = cellToFill.getPossibleSymbols();
+
+        for (int symbol : possibleSymbols) {
+            doku.getStateManager().pushState();
+            cellToFill.setSymbolIndex(symbol);
+            if (solve(doku)) {
+                result++;
             }
-
-
-            remainingCellsToCheck.remove(indexCurrentCell);
+            doku.getStateManager().popState();
         }
-        return doku;
+        return result;
     }
+
 }

app/src/main/java/sudoku/solver/StupidSolver.java

@@ -0,0 +1,50 @@
+package sudoku.solver;
+
+import java.util.concurrent.CancellationException;
+
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+
+/**
+ * Class de test non utilisé
+ */
+public class StupidSolver {
+
+	private static boolean solve(Sudoku sudoku, int index) {
+		// mécanisme d'abandon
+		if (Thread.interrupted())
+			throw new CancellationException("User wants to stop the solver");
+
+		// si tout est bon avant, on a gagné
+		if (!sudoku.isValidCoords(index))
+			return true;
+
+		// si la case n'est pas modifiable, on passe à la suivante
+		if (!sudoku.getCell(index).isMutable())
+			return solve(sudoku, index + 1);
+
+		for (int symbol = 0; symbol < sudoku.getSize(); symbol++) {
+			if (sudoku.getCell(index).trySetValue(symbol)) {
+				// on tente de placer sur la case suivante
+				if (solve(sudoku, index + 1)) {
+					return true;
+				}
+			}
+		}
+		// on a tout essayé et rien n'a fonctionné
+		sudoku.getCell(index).empty();
+		return false;
+	}
+
+	public static boolean solve(MultiDoku doku) {
+		if (doku.isSolved())
+			return true;
+
+		for (Sudoku sudoku : doku.getSubGrids()) {
+			if (!solve(sudoku, 0))
+				return false;
+		}
+		return true;
+	}
+
+}

app/src/main/java/sudoku/structure/Block.java

@@ -0,0 +1,72 @@
+package sudoku.structure;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Class qui représente les block de chaque sudoku,
+ * Un block étant un ensemble de cellule avec une contrainte de block qui lui
+ * ait associé
+ */
+public class Block {
+
+	/**
+	 * L'ensemble des cellules du block
+	 */
+	private final List<Cell> cells;
+
+	/**
+	 * List de sudoku qui contiennent le block
+	 * Pour un acces plus rapide aux sudokus
+	 */
+	private final List<Sudoku> sudokus;
+
+	public Block(List<Cell> cells) {
+		this.cells = cells;
+		this.sudokus = new ArrayList<>();
+	}
+
+	public Block() {
+		this(new ArrayList<>());
+	}
+
+	public List<Cell> getCells() {
+		return cells;
+	}
+
+	/**
+	 * Ajoute une Cell au Block
+	 * 
+	 * @param newCell Cell, à ajouter
+	 */
+	void addCell(Cell newCell) {
+		this.cells.add(newCell);
+	}
+
+	/**
+	 * Cherche si le Block contient déjà un symbole donné.
+	 * 
+	 * @param symbolIndex int, un index de symbole
+	 * @return boolean, true s'il contient le symbole et false sinon
+	 */
+	public boolean containsSymbol(int symbolIndex) {
+		for (Cell cell : getCells()) {
+			if (cell.getSymbolIndex() == symbolIndex)
+				return true;
+		}
+		return false;
+	}
+
+	public boolean containsCell(Cell cell) {
+		for (Cell cellTmp : this.cells) {
+			if (cellTmp.equals(cell)) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	public List<Sudoku> getSudokus() {
+		return sudokus;
+	}
+}

app/src/main/java/sudoku/structure/Cell.java

@@ -0,0 +1,134 @@
+package sudoku.structure;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Représente une case d'un, ou plusieurs, sudoku qui à comme valeur un index de symbole.
+ * Celui ci pourra être remplacer par un symbole en temps voulu.
+ */
+public class Cell {
+
+	/**
+	 * Constante de valeur d'index de symbole quand il n'y en a pas,
+	 * soit que la Cell est vide.
+	 */
+	public static int NOSYMBOL = -1;
+
+	/**
+	 * Block dans lequel est la Cell.
+	 */
+	private Block blockContainer;
+	/**
+	 * L'index du symbole que contient la Cell.
+	 * Il est initialisé à Cell.NOSYMBOL.
+	 */
+	private int symbolIndex = Cell.NOSYMBOL;
+	/**
+	 * Si cette Cell peut être modififié ou non.
+	 */
+	private boolean isMutable = true;
+
+	public Cell() {
+		this(Cell.NOSYMBOL);
+	}
+
+	public Cell(int symbolIndex) {
+		this.symbolIndex = symbolIndex;
+	}
+
+	public Cell(int symbolIndex, boolean isMutable) {
+		this.symbolIndex = symbolIndex;
+		this.isMutable = isMutable;
+	}
+
+	public int getSymbolIndex() {
+		return this.symbolIndex;
+	}
+
+	public void setSymbolIndex(int symbolIndex) {
+		this.symbolIndex = symbolIndex;
+	}
+
+	/**
+	 * Rend la Cell immuable.
+	 */
+	public void setImmutable() {
+		this.isMutable = false;
+	}
+
+	public Block getBlock() {
+		return this.blockContainer;
+	}
+
+	public void setBlock(Block block) {
+		this.blockContainer = block;
+	}
+
+	/**
+	 * Remove the current symbolIndex and returns it
+	 * @return integer symbolIndex cleared
+	 */
+	public int clearCurrentSymbol() {
+		int i = this.symbolIndex;
+		setSymbolIndex(NOSYMBOL);
+		return i;
+	}
+
+	/**
+	 * Renvoie si la Cell est vide ou non.
+	 * @return boolean, true si la Cell est vide, false sinon.
+	 */
+	public boolean isEmpty() {
+		return this.symbolIndex == Cell.NOSYMBOL;
+	}
+
+	/**
+	 * Renvoie si la Cell est modifiable
+	 * @return boolean, true si elle est modifiable ou false sinon.
+	 */
+	public boolean isMutable() {
+		return this.isMutable;
+	}
+
+	/**
+	 * Vide la Cell, en renvoie l'ancien index du symbole qui était dedans.
+	 * @return int, index du symbole anciennement contenue dans la Cell.
+	 */
+    public int empty() {
+		int oldSymbol = this.symbolIndex;
+		this.symbolIndex = Cell.NOSYMBOL;
+		return oldSymbol;
+    }
+
+	public boolean canHaveValue(int value) {
+		for (Sudoku s :getBlock().getSudokus()) {
+			int cellIndex = s.getCells().indexOf(this);
+			// la cellule existe
+			if (cellIndex != -1) {
+				int cellX = cellIndex % s.getSize();
+				int cellY = cellIndex / s.getSize();
+				if (!s.canBePlaced(cellX, cellY, value)) {
+					return false;
+				}
+			}
+		}
+		return true;
+	}
+
+	public List<Integer> getPossibleSymbols() {
+		List<Integer> result = new ArrayList<>();
+		for (int i = 0; i < getBlock().getSudokus().get(0).getSize(); i++) {
+			if (canHaveValue(i))
+				result.add(i);
+		}
+		return result;
+	}
+
+	public boolean trySetValue(int newValue) {
+		if (!canHaveValue(newValue))
+			return false;
+		setSymbolIndex(newValue);
+		return true;
+	}
+}

app/src/main/java/sudoku/structure/Coordinate.java

@@ -0,0 +1,50 @@
+package sudoku.structure;
+
+/**
+ * Représente les coordonnées d'une Cell
+ */
+public class Coordinate {
+
+    /**
+     * L'abscisse de la Cell.
+     */
+    private int x;
+    /**
+     * L'ordonnée de la Cell.
+     */
+    private int y;
+
+    public Coordinate(int x, int y) {
+        this.x = x;
+        this.y = y;
+    }
+
+    public int getX() {
+        return x;
+    }
+
+    public void setX(int x) {
+        this.x = x;
+    }
+
+    public int getY() {
+        return y;
+    }
+
+    public void setY(int y) {
+        this.y = y;
+    }
+
+    public int calculateIndex(int size) {
+        return this.y * size + this.x;
+    }
+
+    public Coordinate add(Coordinate other) {
+        return new Coordinate(this.x + other.x, this.y + other.y);
+    }
+
+    public Coordinate sub(Coordinate other) {
+        return new Coordinate(this.x - other.x, this.y - other.y);
+    }
+
+}

app/src/main/java/sudoku/structure/Difficulty.java

@@ -0,0 +1,38 @@
+package sudoku.structure;
+
+//TODO: melvyn va passer par là
+public enum Difficulty {
+
+	VeryEasy("Très facile", 0.1), Easy("Facile", 0.25), Medium("Moyen", 0.5), Hard("Difficile", 0.75), VeryHard("Impossible", 0.78);
+
+	final double factor;
+	final String displayName;
+
+	private Difficulty(String displayName, double factor) {
+		this.factor = factor;
+		this.displayName = displayName;
+	}
+
+	public String getDisplayName() {
+		return displayName;
+	}
+
+	public double getFactor() {
+		return factor;
+	}
+
+	private static final String[] difficultyNames;
+
+	static {
+		Difficulty[] diffs = Difficulty.values();
+		difficultyNames = new String[diffs.length];
+		for (int i = 0; i < diffs.length; i++) {
+			difficultyNames[i] = diffs[i].getDisplayName();
+		}
+	}
+
+	public static String[] getDifficultyNames() {
+		return difficultyNames;
+	}
+
+}

app/src/main/java/sudoku/structure/MultiDoku.java

@@ -0,0 +1,181 @@
+package sudoku.structure;
+
+import java.util.*;
+
+import sudoku.io.SudokuSerializer;
+
+/**
+ * @class MultiDoku
+ * @brief Représente une grille de Multidoku.
+ *        Une grille de sudoku est un multidoku avec un seul sous-sudoku
+ */
+public class MultiDoku {
+
+	/**
+	 * Liste des sous-Sudoku contenue dans le multidoku.
+	 */
+	private final List<Sudoku> subGrids;
+
+	private final StateManager stateManager;
+
+	public MultiDoku(List<Sudoku> subGrids) {
+		this.subGrids = subGrids;
+		this.stateManager = new StateManager(this);
+	}
+
+	/**
+	 * Renvoie le nombre de sudoku contenu dans ce MultiDoku.
+	 * 
+	 * @return int
+	 */
+	public int getNbSubGrids() {
+		return subGrids.size();
+	}
+
+	/**
+	 * Renvoie la ie sudoku contenue dans ce MultiDoku.
+	 * 
+	 * @param i int, indice du sudoku à renvoyer.
+	 * @return Sudoku, ie Sudoku
+	 */
+	public Sudoku getSubGrid(int i) {
+		return subGrids.get(i);
+	}
+
+	/**
+	 * Renvoie la liste des Cells contenue dans ce MultiDoku,
+	 * soit les Cells contenues de chaques sous-Sudoku.
+	 * 
+	 * @return List<Cell>
+	 */
+	public List<Cell> getCells() {
+		Set<Cell> cellsSet = new HashSet<>();
+		for (Sudoku sudoku : subGrids) {
+			cellsSet.addAll(sudoku.getCells());
+		}
+		return new ArrayList<>(cellsSet);
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append("Multidoku {");
+		for (Sudoku sudoku : subGrids) {
+			sb.append("\n\t").append(sudoku.toString());
+		}
+		sb.append("\n}");
+		return sb.toString();
+	}
+
+	/**
+	 * Renvoie les sous-Sudoku
+	 * 
+	 * @return List<Sudoku>
+	 */
+	public List<Sudoku> getSubGrids() {
+		return this.subGrids;
+	}
+
+	/**
+	 * Check si le MultiDoku est valide, en fonction de ses sous-Sudokus.
+	 * 
+	 * @return boolean, true s'il est valide et false sinon.
+	 */
+	public boolean isSolved() {
+		for (Sudoku sudoku : this.subGrids) {
+			if (!sudoku.isSolved())
+				return false;
+		}
+		return true;
+	}
+
+	/**
+	 * Renvoie la 1re Cell vide des sous-Sudoku.
+	 * 
+	 * @return Cell, une Cell vide, ou null s'il n'y en a pas.
+	 */
+	public Cell getFirstEmptyCell() {
+		for (Sudoku sudoku : this.subGrids) {
+			Cell cellTmp = sudoku.getFirstEmptyCell();
+			if (cellTmp != null) {
+				return cellTmp;
+			}
+		}
+		return null;
+	}
+
+	/**
+	 * Renvoie la liste des Cells préalablement remplies du MultiDoku.
+	 * 
+	 * @return List<Cell>, vide si aucune Cell n'est remplie.
+	 */
+	public List<Cell> getFilledCells() {
+		List<Cell> result = new ArrayList<>();
+		for (Cell cell : this.getCells()) {
+			if (!cell.isEmpty()) {
+				result.add(cell);
+			}
+		}
+		return result;
+	}
+
+	/**
+	 * Renvoie la liste des Cells vides du MultiDoku.
+	 * 
+	 * @return List<Cell>, vide si aucune Cell ne l'est.
+	 */
+	public List<Cell> getEmptyCells() {
+		List<Cell> result = new ArrayList<>();
+		for (Cell cell : this.getCells()) {
+			if (cell.isEmpty()) {
+				result.add(cell);
+			}
+		}
+		return result;
+	}
+
+	/**
+	 * Vide une Cell donnée.
+	 * 
+	 * @param cell Cell, à vider.
+	 */
+	public void empty(Cell cell) {
+		List<Cell> cells = getCells();
+		Cell cellToEmpty = cells.get(cells.indexOf(cell));
+		cellToEmpty.setSymbolIndex(Cell.NOSYMBOL);
+	}
+
+	/**
+	 * Renvoie le nombre de Cell contenue dans le MultiDoku.
+	 * 
+	 * @return int, nombre de Cell dans le MultiDoku.
+	 */
+	public int getNbCells() {
+		return getCells().size();
+	}
+
+	/**
+	 * Change les Cells de ce MultiDoku avec des symboles, en Cells immuables.
+	 */
+	public void setFilledCellsImmutable() {
+		for (Cell filledCell : getFilledCells()) {
+			filledCell.setImmutable();
+		}
+	}
+
+	public StateManager getStateManager() {
+		return stateManager;
+	}
+
+	/**
+	 * Renvoie une Cell vide choisie aléatoirement.
+	 *
+	 * @param rand Random, pour le choix aléatoire.
+	 * @return Cell, une Cell vide.
+	 */
+	public Cell getRandomEmptyCell(Random rand) {
+		List<Cell> emptyCells = getEmptyCells();
+		int randomIndex = rand.nextInt(emptyCells.size());
+		return emptyCells.get(randomIndex);
+	}
+}

app/src/main/java/sudoku/structure/StateManager.java

@@ -0,0 +1,41 @@
+package sudoku.structure;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Stack;
+
+//TODO: doc
+public class StateManager {
+
+	private final Stack<Map<Cell, Integer>> states;
+	private final MultiDoku doku;
+
+	public StateManager(MultiDoku doku) {
+		this.states = new Stack<>();
+		this.doku = doku;
+	}
+
+	public void pushState() {
+		states.add(new HashMap<>());
+		saveState();
+	}
+
+	public void popState() {
+		assert (states.size() > 0);
+		restoreState();
+		states.pop();
+	}
+
+	private void restoreState() {
+		for (var entry : this.states.getLast().entrySet()) {
+			entry.getKey().setSymbolIndex(entry.getValue());
+		}
+	}
+
+	private void saveState() {
+		for (Cell cell : this.doku.getCells()) {
+			states.getLast().put(cell, cell.getSymbolIndex());
+		}
+	}
+
+}

app/src/main/java/sudoku/structure/Sudoku.java

@@ -0,0 +1,295 @@
+package sudoku.structure;
+
+import sudoku.constraint.BlockConstraint;
+import sudoku.constraint.Constraint;
+import sudoku.constraint.IConstraint;
+import sudoku.io.SudokuPrinter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @class Sudoku
+ * @brief Représent un Sudoku
+ */
+public class Sudoku {
+
+	/**
+	 * Liste des Block contenus dans le Sudoku.
+	 */
+	private final List<Block> blocks;
+	/**
+	 * Liste des Cells contenus dans le Sudoku.
+	 */
+	private List<Cell> cells = new ArrayList<>();
+	/**
+	 * Liste des contraintes (TODO) du Sudoku.
+	 */
+	private final List<Constraint> constraints;
+	/**
+	 * Largeur des Blocks s'ils sont rectangulaires, valant 0 si ce n'est pas le cas.
+	 */
+	private int blockWidth;
+
+	public Sudoku(List<Cell> cells, List<Block> blocks, List<Constraint> constraints) {
+		this.cells = cells;
+		this.blocks = blocks;
+		this.constraints = constraints;
+	}
+
+	/**
+	 * Transforme un index de Cell en Coordinate.
+	 *
+	 * @param index int, index d'une Cell.
+	 * @return Coordinate, correspondante à l'index donné.
+	 */
+	public Coordinate toCoords(int index) {
+		return new Coordinate(index % getSize(), index / getSize());
+	}
+
+	/**
+	 * Transforme des coordonées d'une Cell en index.
+	 * @param x int, abscisse.
+	 * @param y int, ordonnée.
+	 * @return int, index correspondant.
+	 */
+	public int toIndex(int x, int y) {
+		return y * getSize() + x;
+	}
+
+	/**
+	 * Vérifie que des coordonnées correspondent bien à une Cell dans le Sudoku.
+	 * @return boolean, valant true si les coordonnées sont dans les bornes du Sudoku, false sinon.
+	 */
+	public boolean isValidCoords(int x, int y) {
+		int index = toIndex(x, y);
+		return isValidCoords(index);
+	}
+
+	/**
+	 * Vérifie que l'index correspond bien à une Cell dans le Sudoku.
+	 * @return boolean, valant true si l'index est dans les bornes du Sudoku, false sinon.
+	 */
+	public boolean isValidCoords(int index) {
+		return index < getSize() * getSize();
+	}
+
+	/**
+	 * Teste si on peut placer la value dans la Cell aux coordonnées x, y d'après les contraintes du Sudoku.
+	 * @param x     int, abscisse de la Cell voulue.
+	 * @param y     int, ordonnée de la Cell voulue.
+	 * @param value int, index du symbole qu'on veut placer.
+	 * @return boolean, true si on peut la placer et false sinon.
+	 */
+	public boolean canBePlaced(int x, int y, int value) {
+		for (Constraint constraint : this.constraints) {
+			if (!constraint.canBePlaced(this, x, y, value)) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+	/**
+	 * Vide la Cell dotn les coordonnées sont renseignées de son symbole.
+	 * @param x int, abscisse de la Cell voulue.
+	 * @param y int, coordonnée de la Cell voulue.
+	 */
+
+	public void clearCell(int x, int y) {
+		assert (isValidCoords(x, y));
+		Cell cell = getCell(x, y);
+		cell.setSymbolIndex(Cell.NOSYMBOL);
+	}
+
+	/**
+	 * Vide toutes les Cell du Sudoku.
+	 */
+	public void clear() {
+		for (int i = 0; i < getSize() * getSize(); i++) {
+			Cell cell = getCell(i);
+			if (cell.isMutable())
+				cell.setSymbolIndex(Cell.NOSYMBOL);
+		}
+	}
+
+	public int getBlockWidth() {
+		return blockWidth;
+	}
+
+	/**
+	 * Place le symbole d'index value dans la Cell de coordonnées précisées.
+	 * @param x     int, abscisse de la Cell voulue.
+	 * @param y     int, coordonnée de la Cell voulue.
+	 * @param value int, index du symbole à placer.
+	 * @return Cell, la Cell qui a été modifiée.
+	 */
+	public Cell setCellSymbol(int x, int y, int value) {
+		assert (isValidCoords(x, y));
+		for (Constraint constraint : this.constraints) {
+			if (!constraint.canBePlaced(this, x, y, value)) {
+				return null;
+			}
+		}
+		Cell cell = getCell(x, y);
+		cell.setSymbolIndex(value);
+		return cell;
+	}
+
+	/**
+	 * Place les symboles d'index contenus dans values dans les cases du Sudoku.
+	 * @param values List<Integer>, liste des index des symboles à placer.
+	 * @return boolean, vaut true si les symboles ont été placés, false sinon.
+	 */
+	public boolean setCellsSymbol(List<Integer> values) {
+		if (values.size() > this.cells.size()) {
+			return false;
+		}
+		for (int i = 0; i < values.size(); i++) {
+			int x = i % this.blocks.size();
+			int y = (i - x) / this.blocks.size();
+			int value = values.get(i);
+			this.setCellSymbol(x, y, value);
+		}
+		return true;
+	}
+
+	/**
+	 * Place les symboles d'index contenus dans values dans les cases du Sudoku et rend ces cases immuables.
+	 * @param values List<Integer>, liste des index des symboles à placer.
+	 * @return boolean, vaut true si les symboles ont été placés, false sinon.
+	 */
+	public boolean setImmutableCellsSymbol(List<Integer> values) {
+		if (values.size() > this.cells.size()) {
+			return false;
+		}
+		for (int i = 0; i < values.size(); i++) {
+			int x = i % this.blocks.size();
+			int y = (i - x) / this.blocks.size();
+			int value = values.get(i);
+			if (value != Cell.NOSYMBOL) {
+				Cell cellPlaced = this.setCellSymbol(x, y, value);
+				if (cellPlaced == null) {
+					continue;
+				}
+				cellPlaced.setImmutable();
+			}
+		}
+		return true;
+	}
+
+	public Cell getCell(int x, int y) {
+		int index = toIndex(x, y);
+		assert (isValidCoords(x, y));
+		try {
+			return this.cells.get(index);
+		} catch (IndexOutOfBoundsException e) {
+			return null;
+		}
+	}
+
+	public Cell getCell(int i) {
+		return this.cells.get(i);
+	}
+
+	public List<Constraint> getConstraints() {
+		return constraints;
+	}
+
+	public int getSize() {
+		return this.blocks.size();
+	}
+
+	public List<Cell> getCells() {
+		return this.cells;
+	}
+
+	public List<Block> getBlocks() {
+		return this.blocks;
+	}
+
+	/**
+	 * Vérifie si une Cell appartient au Sudoku.
+	 * @param cell Cell, cellule dont on veut vérifier l'appartenance au Sudoku.
+	 * @return boolean, vaut true si la Cell appartient au Sudoku.
+	 */
+	public boolean contains(Cell cell) {
+		return this.cells.contains(cell);
+	}
+
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append("Sudoku {");
+		for (int i = 0; i < getSize(); i++) {
+			sb.append("\n\t");
+			for (int j = 0; j < getSize(); j++) {
+				Cell cell = getCell(i, j);
+				sb.append(cell.toString()).append(" ");
+			}
+		}
+		sb.append("\n}");
+		return sb.toString();
+	}
+
+	/**
+	 * Renvoie la 1re Cell vide du Sudoku.
+	 * @return Cell, une Cell vide, ou null s'il n'y en a pas.
+	 */
+	public Cell getFirstEmptyCell() {
+		for (Cell cell : this.cells) {
+			if (cell.isEmpty()) {
+				return cell;
+			}
+		}
+		return null;
+	}
+
+	/**
+	 * Vérifie si le Sudoku est résolue, soit complet et cohérent avec ses contraintes.
+	 * @return boolean, valant true si le Sudoku est résolu, false sinon.
+	 */
+	public boolean isSolved() {
+		boolean isComplete = isComplete();
+		boolean isValid = isValid();
+		return isComplete && isValid;
+	}
+
+	/**
+	 * Vérifie que le Sudoku est complet, soit qu'il n'y ait aucune case vide.
+	 * @return boolean, true si le Sudoku est complet, false sinon.
+	 */
+	private boolean isComplete() {
+		return getFirstEmptyCell() == null;
+	}
+
+	/**
+	 * Vérifie si le Sudoku est valide, soit qu'il est cohérent avec ses contraintes.
+	 * @return bollean, true si le Sudoku est valide, false sinon
+	 */
+	private boolean isValid() {
+		for (int i = 0; i < cells.size(); i++) {
+			Cell cell = getCell(i);
+			if (cell.isEmpty())
+				continue;
+
+			Coordinate coordinate = toCoords(i);
+
+			int symbolPlaced = cell.empty();
+			if (!canBePlaced(coordinate.getX(), coordinate.getY(), symbolPlaced)) {
+				cell.setSymbolIndex(symbolPlaced);
+				return false;
+			}
+			cell.setSymbolIndex(symbolPlaced);
+		}
+		return true;
+	}
+
+	public void setBlockWidth(int blockWidth) {
+		this.blockWidth = blockWidth;
+	}
+
+	public boolean hasConstraint(Constraint constraint) {
+		return this.constraints.contains(constraint);
+	}
+
+}

app/src/main/java/sudoku/structure/SudokuFactory.java

@@ -0,0 +1,319 @@
+package sudoku.structure;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+
+import sudoku.constraint.Constraint;
+import sudoku.io.SudokuSerializer;
+import sudoku.solver.RandomSolver;
+import sudoku.solver.Solver;
+
+public class SudokuFactory {
+
+	/**
+	 * Générateur de nombre aléatoire.
+	 */
+	private static final Random random = new Random();
+
+	/**
+	 * Liste des contraintes par défaut d'un Multi- ou Sudoku.
+	 * Comprend les contraintes de blocs, de lignes, et de colonnes.
+	 */
+	public static List<Constraint> DEFAULT_CONSTRAINTS = Arrays.asList(Constraint.Block, Constraint.Column,
+			Constraint.Line);
+
+	/**
+	 * Créée des Cells et les met dans une liste de taille size.
+	 * @param size int, nombre de Cells à initialiser.
+	 * @return List<Cell>, liste des Cells initialisées.
+	 */
+	private static List<Cell> initCells(int size) {
+		List<Cell> cells = new ArrayList<>(size * size);
+		for (int i = 0; i < size * size; i++) {
+			cells.add(new Cell());
+		}
+		return cells;
+	}
+
+	/**
+	 * Créée des Blocks de taille width par height à partir des cellules données, et les met dans une liste.
+	 * @param cells List<Cell>, liste des Cells à découper en Blocks.
+	 * @param width int, largeur des Blocks à créer.
+	 * @param height int, hauteur des Blocks à créer.
+	 * @return List<Block>, liste des Blocks créés.
+	 */
+	private static List<Block> initRectangleBlocs(List<Cell> cells, int width, int height) {
+		List<Block> blocs = new ArrayList<>();
+		int size = width * height;
+		for (int i = 0; i < size; i++) {
+			Block newBlock = new Block();
+			int blockX = i % height;
+			int blockY = i / height;
+			for (int y = 0; y < height; y++) {
+				for (int x = 0; x < width; x++) {
+					int index = ((y + blockY * height) * size + (x + blockX * width));
+					Cell blockCell = cells.get(index);
+					blockCell.setBlock(newBlock);
+					// List<Block> blockContainers = new ArrayList<>();
+					// blockContainers.add(newBlock);
+					// blockCell.setBlockContainers(blockContainers);
+					newBlock.addCell(blockCell);
+				}
+			}
+			blocs.add(newBlock);
+		}
+		return blocs;
+	}
+
+	/**
+	 * Créée un MultiDoku vide dont les Blocks sont de taille widthBlock par heightBlock.
+	 * @param widthBlock int, largeur des Blocks.
+	 * @param heightBlock int, hauteur des Blocks.
+	 * @return MultiDoku, MultiDoku vide.
+	 */
+	public static MultiDoku createBasicEmptyRectangleDoku(int widthBlock, int heightBlock,
+			List<Constraint> constraints) {
+		return new MultiDoku(Arrays.asList(createRectangleSudoku(widthBlock, heightBlock, constraints)));
+	}
+
+	/**
+	 * Créée un MultiDoku vide dont les Blocks sont carrés de longueur size.
+	 * @param size int, taille des Blocks.
+	 * @return MultiDoku, MultiDoku vide.
+	 */
+	public static MultiDoku createBasicEmptySquareDoku(int size, List<Constraint> constraints) {
+		return new MultiDoku(Arrays.asList(createSquareSudoku(size, constraints)));
+	}
+
+	/**
+	 * Place des Cells immutables de valeurs fournies, aux Coordinate fournies dans le MultiDoku doku fourni.
+	 * @param doku           MultiDoku, MultiDoku à remplir.
+	 * @param immutableCells Map<Coordinate, Integer>, association de Coordinate coordonnées et Integer valeurs, correspondant aux cases à remplir.
+	 */
+	public static void setImmutableCells(MultiDoku doku, Map<Coordinate, Integer> immutableCells) {
+		immutableCells.forEach((coordinate, symbol) -> {
+			for (Sudoku sudoku : doku.getSubGrids()) {
+				Cell cell = sudoku.getCell(coordinate.getX(), coordinate.getY());
+				if (cell != null) {
+					cell.setSymbolIndex(symbol);
+					cell.setImmutable();
+				}
+			}
+		});
+	}
+
+	/**
+	 * Créée un MultiDoku de difficulté difficulty à partir d'un MultiDoku fourni.
+	 *
+	 * @param doku           MultiDoku, MultiDoku dont on doit vider des Cells.
+	 * @param nbCellsToEmpty int, nombre de cases à retirer.
+	 * @return boolean, valant true si un MultiDoku de difficulté donnée peut être créée, false sinon.
+	 * @throws Exception si la difficulté n'est pas compatible avec la taille du MultiDoku.
+	 */
+	public static boolean newDokuFromFilledOne(MultiDoku doku, int nbCellsToEmpty, Solver solver) throws Exception {
+
+		if (nbCellsToEmpty >= doku.getCells().size()) {
+			throw new Exception();
+		}
+
+		if (nbCellsToEmpty == 0) {
+			return true;
+		}
+
+		List<Cell> cellsThatCanBeEmptied = doku.getFilledCells();
+
+		while (!cellsThatCanBeEmptied.isEmpty()) {
+			int index = random.nextInt(cellsThatCanBeEmptied.size());
+			Cell cellToEmpty = cellsThatCanBeEmptied.get(index);
+
+			int oldSymbol = cellToEmpty.empty();
+
+			int nbDokuSultions = solver.countSolution(doku);
+			if (nbDokuSultions == 1) {
+				if (newDokuFromFilledOne(doku, --nbCellsToEmpty, solver)) {
+					return true;
+				}
+			}
+
+			cellToEmpty.setSymbolIndex(oldSymbol);
+			cellsThatCanBeEmptied.remove(cellToEmpty);
+		}
+
+		return newDokuFromFilledOne(doku, --nbCellsToEmpty, solver);
+	}
+
+	/**
+	 * Créée un Sudoku vide dont les Blocks sont de taille widthBlock par heightBlock.
+	 * @param widthBlock  int, largeur des Blocks.
+	 * @param heightBlock int, hauteur des Blocks.
+	 * @return Sudoku, Sudoku vide.
+	 */
+	private static Sudoku createRectangleSudoku(int widthBlock, int heightBlock, List<Constraint> constraints) {
+		int symbolCount = widthBlock * heightBlock;
+		List<Cell> cases = initCells(symbolCount);
+		List<Block> blocs = initRectangleBlocs(cases, widthBlock, heightBlock);
+		Sudoku s = new Sudoku(cases, blocs, constraints);
+		for (Block block : s.getBlocks()) {
+			block.getSudokus().add(s);
+		}
+		s.setBlockWidth(widthBlock);
+		return s;
+	}
+
+	/**
+	 * Créée un Sudoku vide dont les Blocks sont carrés de longueur size.
+	 * @param size int, taille des Blocks.
+	 * @return Sudoku, Sudoku vide.
+	 */
+	private static Sudoku createSquareSudoku(int size, List<Constraint> constraints) {
+		return createRectangleSudoku(size, size, constraints);
+	}
+
+	/**
+	 * Connecte deux Sudokus selon la décalage offset fourni.
+	 * @param sudoku1 Sudoku, premier sudoku à connecter.
+	 * @param sudoku2 Sudoku, second sudoku à connecter.
+	 * @param offset  Coordinate, décalage entre les deux Sudokus.
+	 */
+	private static void linkSquareSudokus(Sudoku sudoku1, Sudoku sudoku2, Coordinate offset) {
+		int blockWidth = sudoku1.getBlockWidth();
+		for (int dx = 0; dx < blockWidth; dx++) {
+			for (int dy = 0; dy < blockWidth; dy++) {
+				int block1X = dx + offset.getX();
+				int block1Y = dy + offset.getY();
+				int block2X = dx;
+				int block2Y = dy;
+
+				if ((block1X < blockWidth) && (block1X >= 0) && (block1Y >= 0) && (block1Y < blockWidth)) {
+					Block block1 = sudoku1.getBlocks().get(block1Y * blockWidth + block1X);
+					Block block2 = sudoku2.getBlocks().get(block2Y * blockWidth + block2X);
+
+					// on remplace le bloc
+					sudoku2.getBlocks().set(block2Y * blockWidth + block2X, block1);
+					block1.getSudokus().add(sudoku2);
+
+					// on remplace les cellules
+					for (int i = 0; i < block1.getCells().size(); i++) {
+						Cell newCell = block1.getCells().get(i);
+						Cell oldCell = block2.getCells().get(i);
+
+						int oldCellIndex = sudoku2.getCells().indexOf(oldCell);
+						sudoku2.getCells().set(oldCellIndex, newCell);
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * Créée un MultiDoku de Blocks carrés de taille size composé de cinq Sudokus, dont un central qui partage chacun de ses Blockss d'angle avec un autre Sudoku.
+	 * @param size int, largeur des Blocks unitraires des Sudokus à crééer.
+	 * @return MultiDoku, MultiDoku de forme X.
+	 */
+	public static MultiDoku createBasicXShapedMultidoku(int size, List<Constraint> constraints) {
+		assert (size > 1);
+
+		/*
+		 * 2 3
+		 *  1
+		 * 4 5
+		 */
+
+		Sudoku sudoku1 = createSquareSudoku(size, constraints);
+		Sudoku sudoku2 = createSquareSudoku(size, constraints);
+		Sudoku sudoku3 = createSquareSudoku(size, constraints);
+		Sudoku sudoku4 = createSquareSudoku(size, constraints);
+		Sudoku sudoku5 = createSquareSudoku(size, constraints);
+
+		linkSquareSudokus(sudoku1, sudoku2, new Coordinate(1 - size, 1 - size));
+		linkSquareSudokus(sudoku1, sudoku3, new Coordinate(size - 1, 1 - size));
+		linkSquareSudokus(sudoku1, sudoku4, new Coordinate(1 - size, size - 1));
+		linkSquareSudokus(sudoku1, sudoku5, new Coordinate(size - 1, size - 1));
+
+		return new MultiDoku(Arrays.asList(sudoku1, sudoku2, sudoku3, sudoku4, sudoku5));
+	}
+
+	/**
+	 * Créée un MultiDoku de Blocks rectangulaires de forme width par height composé de cinq Sudokus,
+	 * dont un central qui partage chacun de ses Blocks d'angle avec un autre
+	 * Sudoku.
+	 *
+	 * @param width int, largeur des Blocks unitraires des Sudokus à crééer.
+	 * @param height int, hauteur des Blocks unitraires des Sudokus à crééer.
+	 * @return MultiDoku, MultiDoku de forme X.
+	 */
+	public static MultiDoku createBasicXShapedMultidoku(int width, int height, List<Constraint> constraints) {
+		assert (width > 1 && height > 1);
+
+		/*
+		 * 2 3
+		 * 1
+		 * 4 5
+		 */
+
+		Sudoku sudoku1 = createRectangleSudoku(width, height, constraints);
+		Sudoku sudoku2 = createRectangleSudoku(width, height, constraints);
+		Sudoku sudoku3 = createRectangleSudoku(width, height, constraints);
+		Sudoku sudoku4 = createRectangleSudoku(width, height, constraints);
+		Sudoku sudoku5 = createRectangleSudoku(width, height, constraints);
+
+		linkSquareSudokus(sudoku1, sudoku2, new Coordinate(1 - width, 1 - height));
+		linkSquareSudokus(sudoku1, sudoku3, new Coordinate(width - 1, 1 - height));
+		linkSquareSudokus(sudoku1, sudoku4, new Coordinate(1 - width, height - 1));
+		linkSquareSudokus(sudoku1, sudoku5, new Coordinate(width - 1, height - 1));
+
+		return new MultiDoku(Arrays.asList(sudoku1, sudoku2, sudoku3, sudoku4, sudoku5));
+	}
+
+	public static void fillDoku(MultiDoku doku, Difficulty difficulty) throws Exception {
+		Solver solver = new RandomSolver();
+		solver.solve(doku);
+		int nbCellsToEmpty = (int) (difficulty.getFactor() * doku.getNbCells());
+		boolean successfull = newDokuFromFilledOne(doku, nbCellsToEmpty, solver);
+		if (!successfull) {
+			throw new Exception("Canno't create this doku with this difficulty");
+		}
+		doku.setFilledCellsImmutable();
+	}
+
+	public static MultiDoku fromfile(String filePath) {
+		try {
+			String content = Files.readString(Paths.get(filePath));
+			MultiDoku doku = SudokuSerializer.deserializeSudoku(content);
+			return doku;
+		} catch (IOException e) {
+			e.printStackTrace();
+			return null;
+		}
+	}
+
+	public static MultiDoku createBasicEmptyRandomBlockDoku(int blockSize, List<Constraint> constraints) {
+		int blockCellCount = blockSize * blockSize;
+		List<Cell> cells = initCells(blockCellCount);
+		List<Cell> homeLessCells = new ArrayList<>();
+		homeLessCells.addAll(cells);
+		List<Block> blocks = new ArrayList<>();
+		Random r = new Random();
+		for (int i = 0 ; i < blockCellCount; i++) {
+			Block b = new Block();
+			for (int j = 0; j < blockCellCount; j++) {
+				int cellIndex = r.nextInt(homeLessCells.size());
+				Cell cell = homeLessCells.remove(cellIndex);
+				b.addCell(cell);
+				cell.setBlock(b);
+			}
+			blocks.add(b);
+		}
+		Sudoku sudoku = new Sudoku(cells, blocks, constraints);
+		for (Block block : blocks) {
+			block.getSudokus().add(sudoku);
+		}
+		return new MultiDoku(Arrays.asList(sudoku));
+	}
+}

app/src/test/java/sudoku/SudokuSerializerTest.java

@@ -0,0 +1,78 @@
+package sudoku;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.util.Random;
+
+import org.json.JSONObject;
+import org.junit.jupiter.api.Test;
+
+import sudoku.io.SudokuSerializer;
+import sudoku.solver.RandomSolver;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.SudokuFactory;
+
+public class SudokuSerializerTest {
+
+    void testSerializeWithSize(int blockWidth, int blockHeight) {
+        var sudoku = SudokuFactory.createBasicEmptyRectangleDoku(blockWidth, blockHeight,
+                SudokuFactory.DEFAULT_CONSTRAINTS);
+        new RandomSolver().solve(sudoku);
+        JSONObject data = SudokuSerializer.serializeSudoku(sudoku);
+        MultiDoku multiDoku = SudokuSerializer.deserializeSudoku(data);
+        assertTrue(data.toString().equals(SudokuSerializer.serializeSudoku(multiDoku).toString()));
+    }
+
+    void testSaveWithSize(int blockWidth, int blockHeight) {
+        MultiDoku doku = SudokuFactory.createBasicEmptyRectangleDoku(blockWidth, blockHeight,
+                SudokuFactory.DEFAULT_CONSTRAINTS);
+        new RandomSolver().solve(doku);
+        String savePath = SudokuSerializer.saveMultiDoku(doku);
+        MultiDoku otherDoku = null;
+        try {
+            otherDoku = SudokuFactory.fromfile(savePath);
+            assert (otherDoku != null);
+
+            assertEquals(SudokuSerializer.serializeSudoku(doku).toString(),
+                    SudokuSerializer.serializeSudoku(otherDoku).toString());
+            // clean file after test
+            File fileToDelete = new File(savePath);
+            fileToDelete.delete();
+        } catch (Exception e) {
+            e.printStackTrace();
+            assert false;
+        }
+    }
+
+    void testSerializeX(int size) {
+        var sudoku = SudokuFactory.createBasicXShapedMultidoku(size, SudokuFactory.DEFAULT_CONSTRAINTS);
+        new RandomSolver().solve(sudoku);
+        JSONObject data = SudokuSerializer.serializeSudoku(sudoku);
+        MultiDoku multiDoku = SudokuSerializer.deserializeSudoku(data);
+
+        assertTrue(data.toString().equals(SudokuSerializer.serializeSudoku(multiDoku).toString()));
+    }
+
+    @Test
+    void testSerialize() {
+        Random r = new Random();
+        int testCount = 20;
+        for (int i = 0; i < testCount; i++) {
+            int blockWidth = r.nextInt(4) + 1;
+            int blockHeight = r.nextInt(4) + 1;
+            testSerializeWithSize(blockWidth, blockHeight);
+        }
+        for (int i = 0; i < testCount; i++) {
+            int blockWidth = r.nextInt(4) + 1;
+            int blockHeight = r.nextInt(4) + 1;
+            testSaveWithSize(blockWidth, blockHeight);
+        }
+        for (int i = 0; i < testCount; i++) {
+            int size = r.nextInt(2) + 2;
+            testSerializeX(size);
+        }
+    }
+
+}

app/src/test/java/sudoku/solver/SolverTest.java

@@ -0,0 +1,106 @@
+package sudoku.solver;
+
+import gui.Symbols;
+import org.junit.jupiter.api.Test;
+import sudoku.io.SudokuPrinter;
+import sudoku.io.SudokuSerializer;
+import sudoku.structure.Cell;
+import sudoku.structure.MultiDoku;
+import sudoku.structure.Sudoku;
+import sudoku.structure.SudokuFactory;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.List;
+import java.util.Random;
+
+class SolverTest {
+
+	@Test
+	void solveTest() {
+		Random rand = new Random();
+
+		MultiDoku dokuToTest = SudokuFactory.createBasicEmptySquareDoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+		MultiDoku dokuResult = SudokuFactory.createBasicEmptySquareDoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+
+		Sudoku sudokuToTest = dokuToTest.getSubGrid(0);
+		Sudoku sudokuResult = dokuResult.getSubGrid(0);
+
+		int ns = Cell.NOSYMBOL;
+		List<Integer> immutableCells = List.of(ns, ns, 0, ns, ns, 2, 8, ns, 1,
+				ns, 3, ns, ns, 5, 6, 7, ns, ns,
+				ns, ns, ns, 8, ns, 7, ns, ns, 6,
+				0, ns, 1, ns, ns, ns, ns, ns, ns,
+				4, 8, 7, 5, 1, ns, 6, ns, ns,
+				6, ns, 3, 2, ns, ns, ns, 8, 0,
+				ns, ns, 6, ns, ns, 8, ns, 7, 5,
+				8, 0, ns, 7, ns, 5, 2, ns, 3,
+				5, ns, ns, ns, 3, 1, 0, ns, ns);
+
+		assert (sudokuToTest.setImmutableCellsSymbol(immutableCells));
+
+		//SudokuPrinter.printRectangleSudoku(dokuToTest.getSubGrid(0), 3, 3);
+		SudokuPrinter.printMultiDoku(dokuToTest, 3, 3, Symbols.Numbers);
+
+		List<Integer> correctCells = List.of(7, 6, 0, 3, 4, 2, 8, 5, 1,
+				2, 3, 8, 1, 5, 6, 7, 0, 4,
+				1, 4, 5, 8, 0, 7, 3, 2, 6,
+				0, 2, 1, 6, 8, 3, 5, 4, 7,
+				4, 8, 7, 5, 1, 0, 6, 3, 2,
+				6, 5, 3, 2, 7, 4, 1, 8, 0,
+				3, 1, 6, 0, 2, 8, 4, 7, 5,
+				8, 0, 4, 7, 6, 5, 2, 1, 3,
+				5, 7, 2, 4, 3, 1, 0, 6, 8);
+
+		sudokuResult.setCellsSymbol(correctCells);
+
+		System.out.println("\n****************************Doku Control\n");
+		SudokuPrinter.printRectangleSudoku(sudokuResult, 3, 3, Symbols.Russian);
+
+		assert (dokuResult.isSolved());
+
+		new RandomSolver().solve(dokuToTest);
+
+		System.out.println("\n****************************\nDoku solved");
+		//SudokuPrinter.printRectangleSudoku(dokuToTest.getSubGrid(0), 3, 3);
+		SudokuPrinter.printMultiDoku(dokuToTest, 3, 3, Symbols.Emojis);
+
+		assert (dokuToTest.isSolved());
+
+		for (Cell cell : sudokuToTest.getCells()) {
+			cell.setImmutable();
+		}
+
+		for (Cell cell : sudokuResult.getCells()) {
+			cell.setImmutable();
+		}
+
+		assertEquals(SudokuSerializer.serializeSudoku(dokuResult).toString(),
+				SudokuSerializer.serializeSudoku(dokuToTest).toString());
+
+		MultiDoku dokuToTest2 = SudokuFactory.createBasicEmptySquareDoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+		Sudoku sudokuToTest2 = dokuToTest2.getSubGrid(0);
+
+		List<Integer> immutableCells2 = List.of(ns, ns, 0, ns, ns, 2, 8, ns, 1,
+				1, 3, ns, ns, 5, 6, 7, ns, ns,
+				ns, ns, ns, 8, ns, 7, ns, ns, 6,
+				0, ns, 1, ns, ns, ns, ns, ns, ns,
+				4, 8, 7, 5, 1, ns, 6, ns, ns,
+				6, ns, 3, 2, ns, ns, ns, 8, 0,
+				ns, ns, 6, ns, ns, 8, ns, 7, 5,
+				8, 0, ns, 7, ns, 5, 2, ns, 3,
+				5, ns, ns, ns, 3, 1, 0, ns, ns);
+		sudokuToTest2.setImmutableCellsSymbol(immutableCells2);
+
+		boolean isSolved = new RandomSolver().solve(dokuToTest2);
+
+		assert (!isSolved);
+
+		MultiDoku dokuToTest3 = SudokuFactory.createBasicEmptySquareDoku(3, SudokuFactory.DEFAULT_CONSTRAINTS);
+
+		new RandomSolver().solve(dokuToTest3);
+
+		//SudokuPrinter.printRectangleSudoku(dokuToTest3.getSubGrid(0), 3, 3);
+		SudokuPrinter.printMultiDoku(dokuToTest3, 3, 3, Symbols.Letters);
+	}
+}

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
 networkTimeout=10000
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

imgui.ini

@@ -0,0 +1,10 @@
+[Window][Debug##Default]
+Pos=60,60
+Size=400,400
+Collapsed=0
+
+[Window][Window]
+Pos=32,164
+Size=1096,529
+Collapsed=1
+