fix steps

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

@@ -1,5 +1,7 @@
 package gui.menu;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.concurrent.CancellationException;
 
 import gui.widget.SudokuRenderer;
@@ -11,6 +13,7 @@ import sudoku.solver.HintHelper;
 import sudoku.solver.HumanSolver;
 import sudoku.solver.MixedSolver;
 import sudoku.solver.Solver;
+import sudoku.solver.SolverStep;
 import sudoku.solver.HintHelper.Hint;
 import sudoku.structure.MultiDoku;
 
@@ -90,8 +93,9 @@ public class SudokuView extends BaseView {
 
 	private void startSolve(Solver solver) {
 		resolveThread = new Thread(() -> {
+			List<SolverStep> steps = new ArrayList<>();
 			try {
-				unresolved = !solver.solve(this.doku);
+				unresolved = !solver.solve(this.doku, steps);
 			} catch (CancellationException e) {
 				System.out.println("The user is bored !");
 			}

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

@@ -15,7 +15,7 @@ public class BacktrackingSolver implements Solver {
 	 * @return boolean, valant true si le MultiDoku est résolu, false sinon.
 	 */
 	@Override
-	public boolean solve(MultiDoku doku) {
+	public boolean solve(MultiDoku doku, List<SolverStep> steps) {
 		if (Thread.interrupted())
 			throw new CancellationException("User wants to stop the solver");
 
@@ -34,14 +34,14 @@ public class BacktrackingSolver implements Solver {
 		}
 
 		for (int symbol : possibleSymbols) {
-
 			cellToFill.setSymbolIndex(symbol);
-			if (this.solve(doku)) {
+			addStep(cellToFill, steps);
+			if (this.solve(doku, steps)) {
 				return true;
 			} else {
 				cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+				addStep(cellToFill, steps);
 			}
-
 		}
 		return false;
 	}

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

@@ -19,7 +19,7 @@ public class HumanSolver implements Solver {
 	 * @return boolean, valant true si le MultiDoku est résolu, false sinon.
 	 */
 	@Override
-	public boolean solve(MultiDoku doku) {
+	public boolean solve(MultiDoku doku, List<SolverStep> steps) {
 		if (Thread.interrupted())
 			throw new CancellationException("User wants to stop the solver");
 
@@ -47,8 +47,9 @@ public class HumanSolver implements Solver {
 			}
 
 			cellToFill.setSymbolIndex(possibleSymbols.getFirst());
+			addStep(cellToFill, steps);
 
-			return this.solve(doku);
+			return this.solve(doku, steps);
 		}
 
 		return doku.isSolved();

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

@@ -21,7 +21,7 @@ public class MixedSolver implements Solver{
      * @return boolean, valant true si le MultiDoku est résolu, false sinon.
      */
     @Override
-    public boolean solve(MultiDoku doku) {
+    public boolean solve(MultiDoku doku, List<SolverStep> steps) {
         Random rand = new Random();
 
         if (Thread.interrupted()) {
@@ -49,7 +49,8 @@ public class MixedSolver implements Solver{
 
         if (possibleSymbols.size() == 1) {
             cellToFill.setSymbolIndex(possibleSymbols.getFirst());
-            if (this.solve(doku)) {
+            addStep(cellToFill, steps);
+            if (this.solve(doku, steps)) {
                 return true;
             }
         }
@@ -59,10 +60,12 @@ public class MixedSolver implements Solver{
             int nextSymbol = possibleSymbols.get(nextPossibleSymbolIndex);
 
             cellToFill.setSymbolIndex(nextSymbol);
-            if (this.solve(doku)) {
+            addStep(cellToFill, steps);
+            if (this.solve(doku, steps)) {
                 return true;
             }
             cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+            addStep(cellToFill, steps);
             possibleSymbols.remove(nextPossibleSymbolIndex);
 
         }

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

@@ -22,7 +22,7 @@ public class RandomSolver implements Solver {
      * @return boolean, true s'il est résolu ou false s'il ne l'est pas.
      */
     @Override
-    public boolean solve(MultiDoku doku) {
+    public boolean solve(MultiDoku doku, List<SolverStep> steps) {
         Random rand = new Random();
 
         if (Thread.interrupted())
@@ -51,10 +51,12 @@ public class RandomSolver implements Solver {
             int nextSymbol = possibleSymbols.get(nextPossibleSymbolIndex);
 
             cellToFill.setSymbolIndex(nextSymbol);
-            if (this.solve(doku)) {
+            addStep(cellToFill, steps);
+            if (this.solve(doku, steps)) {
                 return true;
             }
             cellToFill.setSymbolIndex(Cell.NOSYMBOL);
+            addStep(cellToFill, steps);
             possibleSymbols.remove(nextPossibleSymbolIndex);
 
         }

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

@@ -13,7 +13,11 @@ public interface Solver {
      */
     public static final Logger logger = Logger.getLogger("SolverLogger");
 
-	boolean solve(MultiDoku doku);
+    boolean solve(MultiDoku doku, List<SolverStep> solverSteps);
+
+    default boolean solve(MultiDoku doku) {
+        return solve(doku, null);
+    }
 
     /**
      * Compte le nombre de solutions possibles au MultiDoku passé en paramètres.
@@ -44,4 +48,10 @@ public interface Solver {
         return result;
     }
 
+    default void addStep(Cell cell, List<SolverStep> steps) {
+        if (steps == null)
+            return;
+        steps.add(new SolverStep(cell));
+    }
+
 }

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

@@ -0,0 +1,23 @@
+package sudoku.solver;
+
+import sudoku.structure.Cell;
+
+public class SolverStep {
+
+	private final Cell cell;
+	private final int newValue;
+
+	public SolverStep(Cell cell) {
+		this.cell = cell;
+		this.newValue = cell.getSymbolIndex();
+	}
+
+	public int getNewValue() {
+		return newValue;
+	}
+
+	public Cell getCell() {
+		return cell;
+	}
+
+}