Implement State component and systems

Closes #10

artbox/src/main/java/com/whoshuu/artbox/WorldView.java

@@ -11,9 +11,11 @@
 import com.whoshuu.artbox.R;
 import com.whoshuu.artbox.artemis.EntitySystem;
 import com.whoshuu.artbox.system.AnimationSystem;
+import com.whoshuu.artbox.system.AnimationStateSystem;
 import com.whoshuu.artbox.system.BodyPositionSystem;
 import com.whoshuu.artbox.system.DebugBodyRenderSystem;
 import com.whoshuu.artbox.system.SpriteRenderSystem;
+import com.whoshuu.artbox.system.SpriteStateSystem;
 import com.whoshuu.artbox.system.SystemType;
 import com.whoshuu.artbox.system.TouchUpdateSystem;
 
@@ -42,6 +44,8 @@ public WorldView(Context context, AttributeSet attrs) {
         setFocusable(true);
 
         addSystem(new BodyPositionSystem(), SystemType.BASE_LOGIC);
+        addSystem(new AnimationStateSystem(), SystemType.BASE_LOGIC);
+        addSystem(new SpriteStateSystem(), SystemType.BASE_LOGIC);
         addSystem(new AnimationSystem(), SystemType.BASE_LOGIC);
         addSystem(new SpriteRenderSystem(), SystemType.BASE_RENDER);
         addSystem(new DebugBodyRenderSystem(), SystemType.BASE_RENDER);

artbox/src/main/java/com/whoshuu/artbox/component/StateComponent.java

@@ -0,0 +1,52 @@
+package com.whoshuu.artbox.component;
+
+import java.util.ArrayList;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import com.whoshuu.artbox.artemis.utils.JSONComponent;
+
+public class StateComponent extends JSONComponent {
+
+    public StateComponent() {
+        states = new ArrayList<String>();
+    }
+
+    public String getState() {
+        return current;
+    }
+
+    public void setState(String state) {
+        if (states.contains(state)) {
+            current = state;
+        }
+    }
+
+    @Override
+    public void fromJSON(JSONObject json, float x, float y, float angle) throws JSONException {
+    	/* 
+    	 * "type": "com.whoshuu.artbox.component.StateComponent",
+         * "states": [
+         *   "name_of_first_state",
+         *   "name_of_second_state",
+         *   ...
+         *   "name_of_last_state"
+         * ]
+         *
+         * The first state is assumed to be the first activated state.
+         */
+        JSONArray jsonStates = json.getJSONArray("states");
+        for (int i = 0; i < jsonStates.length(); i++) {
+            String state = jsonStates.getString(i);
+            states.add(state);
+            if (i == 0) {
+                setState(state);
+            }
+        }
+    }
+
+    private ArrayList<String> states;
+    private String current;
+}

artbox/src/main/java/com/whoshuu/artbox/system/AnimationStateSystem.java

@@ -0,0 +1,41 @@
+package com.whoshuu.artbox.system;
+
+import com.whoshuu.artbox.artemis.ComponentMapper;
+import com.whoshuu.artbox.artemis.Entity;
+import com.whoshuu.artbox.artemis.EntitySystem;
+import com.whoshuu.artbox.component.AnimationComponent;
+import com.whoshuu.artbox.component.StateComponent;
+
+public class AnimationStateSystem extends EntitySystem {
+
+    @SuppressWarnings("unchecked")
+    public AnimationStateSystem() {
+        super(AnimationComponent.class, StateComponent.class);
+    }
+
+    @Override
+    protected void initialize() {
+        this.animations = new ComponentMapper<AnimationComponent>(AnimationComponent.class,
+                this.world);
+        this.states = new ComponentMapper<StateComponent>(StateComponent.class, this.world);
+        super.initialize();
+    }
+
+    @Override
+    protected void processEntity(Entity entity) {
+        StateComponent stateComponent = states.get(entity);
+        AnimationComponent animation = animations.get(entity);
+
+        if (!animation.getState().equals(stateComponent.getState())) {
+            animation.setState(stateComponent.getState());
+        }
+    }
+
+    @Override
+    protected boolean checkProcessing() {
+        return true;
+    }
+
+    private ComponentMapper<AnimationComponent> animations;
+    private ComponentMapper<StateComponent> states;
+}

artbox/src/main/java/com/whoshuu/artbox/system/SpriteStateSystem.java

@@ -0,0 +1,40 @@
+package com.whoshuu.artbox.system;
+
+import com.whoshuu.artbox.artemis.ComponentMapper;
+import com.whoshuu.artbox.artemis.Entity;
+import com.whoshuu.artbox.artemis.EntitySystem;
+import com.whoshuu.artbox.component.SpriteComponent;
+import com.whoshuu.artbox.component.StateComponent;
+
+public class SpriteStateSystem extends EntitySystem {
+
+    @SuppressWarnings("unchecked")
+    public SpriteStateSystem() {
+        super(SpriteComponent.class, StateComponent.class);
+    }
+
+    @Override
+    protected void initialize() {
+        this.sprites = new ComponentMapper<SpriteComponent>(SpriteComponent.class, this.world);
+        this.states = new ComponentMapper<StateComponent>(StateComponent.class, this.world);
+        super.initialize();
+    }
+
+    @Override
+    protected void processEntity(Entity entity) {
+        StateComponent stateComponent = states.get(entity);
+        SpriteComponent sprite = sprites.get(entity);
+
+        if (!sprite.getState().equals(stateComponent.getState())) {
+            sprite.setState(stateComponent.getState());
+        }
+    }
+
+    @Override
+    protected boolean checkProcessing() {
+        return true;
+    }
+
+    private ComponentMapper<SpriteComponent> sprites;
+    private ComponentMapper<StateComponent> states;
+}