choosenField returns only Fields with state != shot

src/main/java/de/tims/fleetstorm/ai/Logic.java

@@ -1,9 +1,24 @@
 package de.tims.fleetstorm.ai;
 
+import java.util.ArrayList;
+import java.util.Random;
+
+import de.tims.fleetstorm.matchfield.Matchfield;
+
 public class Logic {
 
-	public int[] chooseField() {
-		return new int[] {};
+	public int[] chooseField(Matchfield matchfield) {
+		ArrayList<int[]> possibleFields = new ArrayList<int[]>();
+		for (int x = 0; x < Math.sqrt(matchfield.getSize()); x++) {
+			for (int y = 0; y < Math.sqrt(matchfield.getSize()); y++) {
+				if (matchfield.getState(x, y) == Matchfield.EMPTY || matchfield.getState(x, y) == Matchfield.SHIP) {
+					possibleFields.add(new int[] { x, y });
+				}
+			}
+		}
+		Random randy = new Random();
+
+		return possibleFields.get(randy.nextInt(possibleFields.size() - 1));
 	}
 
 }

src/test/java/de/tims/fleetstorm/ai/LogicTest.java

@@ -1,16 +1,35 @@
 package de.tims.fleetstorm.ai;
 
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 import org.junit.jupiter.api.Test;
 
+import de.tims.fleetstorm.matchfield.Matchfield;
+
 class LogicTest {
 	Logic logic = new Logic();
+	int size = 3;
+	private Matchfield matchfield = new Matchfield(size);
 
 	@Test
-	void testFielIsNotNull() {
-		int[] calcResult = logic.chooseField();
+	void testFieldIsNotNull() {
+		int[] calcResult = logic.chooseField(matchfield);
 		assertNotNull(calcResult);
 	}
 
+	@Test
+	void testChoosenFieldHasNotStateShot() {
+		matchfield.createMatchfield();
+		for (int x = 0; x < size; x++) {
+			for (int y = 0; y < size; y++) {
+				// matchfield.setState(x, y, Matchfield.SHOT);
+			}
+		}
+		// matchfield.setState(0, 0, Matchfield.EMPTY);
+
+		int[] choosenField = logic.chooseField(matchfield);
+		int calcState = matchfield.getState(choosenField[0], choosenField[1]);
+		assertNotEquals(calcState, Matchfield.SHOT);
+	}
 }