Create AI scaffolding

api/src/main/java/com/bartlomiejpluta/base/api/game/ai/AI.java

@@ -0,0 +1,8 @@
+package com.bartlomiejpluta.base.api.game.ai;
+
+import com.bartlomiejpluta.base.api.game.map.layer.object.ObjectLayer;
+
+@FunctionalInterface
+public interface AI {
+   void nextActivity(ObjectLayer layer, float dt);
+}

api/src/main/java/com/bartlomiejpluta/base/api/game/ai/NPC.java

@@ -0,0 +1,7 @@
+package com.bartlomiejpluta.base.api.game.ai;
+
+import com.bartlomiejpluta.base.api.game.entity.Entity;
+
+public interface NPC extends Entity {
+   AI getStrategy();
+}

api/src/main/java/com/bartlomiejpluta/base/api/game/ai/RandomMovementAI.java

@@ -0,0 +1,34 @@
+package com.bartlomiejpluta.base.api.game.ai;
+
+import com.bartlomiejpluta.base.api.game.entity.Direction;
+import com.bartlomiejpluta.base.api.game.map.layer.object.ObjectLayer;
+
+import java.util.Random;
+
+public class RandomMovementAI implements AI {
+   private final Random random = new Random();
+   private final NPC npc;
+
+   private final float intervalSeconds;
+   private float accumulator = 0.0f;
+   private float threshold = 0.0f;
+
+   public RandomMovementAI(NPC npc, float intervalSeconds) {
+      this.npc = npc;
+      this.intervalSeconds = intervalSeconds;
+   }
+
+   @Override
+   public void nextActivity(ObjectLayer layer, float dt) {
+      if (!npc.isMoving()) {
+         if (accumulator > threshold) {
+            Direction direction = Direction.values()[random.nextInt(4)];
+            layer.pushMovement(npc.prepareMovement(direction));
+            accumulator = 0.0f;
+            threshold = random.nextFloat() * intervalSeconds;
+         }
+
+         accumulator += dt;
+      }
+   }
+}

api/src/main/java/com/bartlomiejpluta/base/api/game/entity/Entity.java

@@ -36,4 +36,8 @@ public interface Entity extends Placeable, Renderable, Updatable {
    void onAdd(ObjectLayer layer);
 
    void onRemove(ObjectLayer layer);
+
+   boolean isBlocking();
+
+   void setBlocking(boolean blocking);
 }

api/src/main/java/com/bartlomiejpluta/base/api/game/entity/EntityDelegate.java

@@ -171,6 +171,16 @@ public abstract class EntityDelegate implements Entity {
       entity.onRemove(layer);
    }
 
+   @Override
+   public boolean isBlocking() {
+      return entity.isBlocking();
+   }
+
+   @Override
+   public void setBlocking(boolean blocking) {
+      entity.setBlocking(blocking);
+   }
+
    @Override
    public void update(float dt) {
       entity.update(dt);

engine/src/main/java/com/bartlomiejpluta/base/engine/world/entity/model/DefaultEntity.java

@@ -10,6 +10,7 @@ import com.bartlomiejpluta.base.engine.world.entity.config.EntitySpriteConfigura
 import com.bartlomiejpluta.base.engine.world.movement.MovableSprite;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
+import lombok.Setter;
 import org.joml.Vector2f;
 import org.joml.Vector2i;
 
@@ -35,6 +36,10 @@ public class DefaultEntity extends MovableSprite implements Entity {
       return isMoving();
    }
 
+   @Getter
+   @Setter
+   private boolean blocking;
+
    @Override
    public Vector2f[] getSpriteAnimationFramesPositions() {
       var row = spriteDirectionRows.get(faceDirection);

engine/src/main/java/com/bartlomiejpluta/base/engine/world/map/layer/object/DefaultObjectLayer.java

@@ -1,5 +1,6 @@
 package com.bartlomiejpluta.base.engine.world.map.layer.object;
 
+import com.bartlomiejpluta.base.api.game.ai.NPC;
 import com.bartlomiejpluta.base.api.game.camera.Camera;
 import com.bartlomiejpluta.base.api.game.entity.Direction;
 import com.bartlomiejpluta.base.api.game.entity.Entity;
@@ -108,6 +109,12 @@ public class DefaultObjectLayer implements ObjectLayer {
          default -> true;
       };
 
+      for (var entity : entities) {
+         if (entity.isBlocking() && entity.getCoordinates().equals(target)) {
+            return false;
+         }
+      }
+
       return isTargetReachable && canMoveFromCurrentTile;
    }
 
@@ -131,6 +138,10 @@ public class DefaultObjectLayer implements ObjectLayer {
          }
 
          entity.update(dt);
+
+         if (entity instanceof NPC) {
+            ((NPC) entity).getStrategy().nextActivity(this, dt);
+         }
       }
    }