Implement GenerateElemBall action

src/main/java/emu/grasscutter/data/binout/AbilityModifier.java

@@ -327,6 +327,11 @@ public class AbilityModifier implements Serializable {
         public AbilityModifierAction[] successActions;
         public AbilityModifierAction[] failActions;
 
+        public int dropType;
+        public DynamicFloat baseEnergy;
+        public DynamicFloat ratio;
+        public int configID;
+
         public int param1;
         public int param2;
         public int param3;

src/main/java/emu/grasscutter/data/binout/config/ConfigLevelEntity.java

@@ -1,9 +1,10 @@
 package emu.grasscutter.data.binout.config;
 
 import emu.grasscutter.data.binout.config.fields.ConfigAbilityData;
-import java.util.List;
 import lombok.Getter;
 
+import java.util.List;
+
 public class ConfigLevelEntity {
 
     @Getter private List<ConfigAbilityData> abilities;
@@ -11,4 +12,6 @@ public class ConfigLevelEntity {
     @Getter private List<ConfigAbilityData> avatarAbilities;
     @Getter private List<ConfigAbilityData> teamAbilities;
     @Getter private List<Integer> preloadMonsterEntityIDs;
+
+    @Getter private String dropElemControlType;
 }

src/main/java/emu/grasscutter/game/ability/actions/ActionGenerateElemBall.java

@@ -0,0 +1,86 @@
+package emu.grasscutter.game.ability.actions;
+
+import com.google.protobuf.ByteString;
+import com.google.protobuf.InvalidProtocolBufferException;
+
+import emu.grasscutter.Grasscutter;
+import emu.grasscutter.data.GameData;
+import emu.grasscutter.data.binout.AbilityModifier.AbilityModifierAction;
+import emu.grasscutter.data.binout.config.ConfigLevelEntity;
+import emu.grasscutter.game.ability.Ability;
+import emu.grasscutter.game.entity.EntityAvatar;
+import emu.grasscutter.game.entity.EntityItem;
+import emu.grasscutter.game.entity.GameEntity;
+import emu.grasscutter.game.props.ItemUseOp;
+import emu.grasscutter.game.props.SceneType;
+import emu.grasscutter.net.proto.AbilityActionGenerateElemBallOuterClass.AbilityActionGenerateElemBall;
+import emu.grasscutter.utils.Position;
+
+@AbilityAction(AbilityModifierAction.Type.GenerateElemBall)
+public class ActionGenerateElemBall extends AbilityActionHandler {
+    @Override
+    public boolean execute(Ability ability, AbilityModifierAction action, ByteString abilityData, GameEntity target) {
+        GameEntity owner = ability.getOwner();
+
+        AbilityActionGenerateElemBall generateElemBall;
+        try {
+            generateElemBall = AbilityActionGenerateElemBall.parseFrom(abilityData);
+        } catch (InvalidProtocolBufferException e) {
+            return false;
+        }
+
+        //Check if we should allow elem ball generation
+        if(action.dropType == 0x0) {
+            String levelEntityConfig = owner.getScene().getSceneData().getLevelEntityConfig();
+            ConfigLevelEntity config = GameData.getConfigLevelEntityDataMap().get(levelEntityConfig);
+            if(config != null && config.getDropElemControlType() != null && config.getDropElemControlType().compareTo("None") == 0) {
+                Grasscutter.getLogger().warn("This level config don't allow element balls");
+                return true;
+            }
+        } else if(action.dropType == 0x1) {
+            if(owner.getScene().getSceneData().getSceneType() != SceneType.SCENE_WORLD) {
+                Grasscutter.getLogger().warn("This level config only allows element balls on big world");
+                return true;
+            }
+        } //Else the drop is forced
+
+        var energy = action.baseEnergy.get(ability) * action.ratio.get(ability);
+        if(energy <= 0.0) return true;
+
+        var itemData = GameData.getItemDataMap().get(action.configID);
+        if(itemData == null) {
+            Grasscutter.getLogger().warn("configID {} not found", action.configID);
+            return false;
+        }
+
+        if(itemData.getItemUse() == null || itemData.getItemUse().isEmpty()) {
+            Grasscutter.getLogger().warn("Item {} has no item use array", action.configID);
+            return true;
+        }
+
+        var itemUse = itemData.getItemUse().get(0);
+        double requiredEnergy;
+        switch(itemUse.getUseOp()) {
+            case ITEM_USE_ADD_ELEM_ENERGY: requiredEnergy = Integer.parseInt(itemUse.getUseParam()[1]); break;
+            case ITEM_USE_ADD_ALL_ENERGY: requiredEnergy = Integer.parseInt(itemUse.getUseParam()[0]); break;
+            default:
+                Grasscutter.getLogger().warn("UseOp not implemented", itemUse.getUseOp());
+                return false;
+        }
+
+        var amountGenerated = (int)Math.ceil(energy / requiredEnergy);
+        if(amountGenerated >= 21) {
+            Grasscutter.getLogger().warn("Attempt to generate more than 20 element balls {}", amountGenerated);
+            return false;
+        }
+
+        Grasscutter.getLogger().debug("Generating {} of {} element balls", amountGenerated, action.configID);
+        for(int i = 0; i < amountGenerated; i++) {
+            EntityItem energyBall = new EntityItem(owner.getScene(), (owner instanceof EntityAvatar avatar) ? avatar.getPlayer() : null, itemData, new Position(generateElemBall.getPos()), new Position(generateElemBall.getRot()), 1);
+            owner.getScene().addEntity(energyBall);
+        }
+
+        return true;
+    }
+}
+

src/main/java/emu/grasscutter/game/entity/EntityItem.java

@@ -37,14 +37,19 @@ public class EntityItem extends EntityBaseGadget {
         this(scene, player, itemData, pos, count, true);
     }
 
-    // In official game, some drop items are shared to all players, and some other items are
+    public EntityItem(Scene scene, Player player, ItemData itemData, Position pos, Position rotation, int count) {
-    // independent to all players
+        this(scene, player, itemData, pos, rotation, count, true);
-    // For example, if you killed a monster in MP mode, all players could get drops but rarity and
+    }
-    // number of them are different
+
+    public EntityItem(Scene scene, Player player, ItemData itemData, Position pos, int count, boolean share) {
+        this(scene, player, itemData, pos, null, count, share);
+    }
+
+    // In official game, some drop items are shared to all players, and some other items are independent to all players
+    // For example, if you killed a monster in MP mode, all players could get drops but rarity and number of them are different
     // but if you broke regional mine, when someone picked up the drop then it disappeared
-    public EntityItem(
+    public EntityItem(Scene scene, Player player, ItemData itemData, Position pos, Position rotation, int count, boolean share) {
-            Scene scene, Player player, ItemData itemData, Position pos, int count, boolean share) {
+        super(scene, pos, rotation);
-        super(scene, pos, null);
         this.id = getScene().getWorld().getNextEntityId(EntityIdType.GADGET);
         this.guid =
                 player == null ? scene.getWorld().getHost().getNextGameGuid() : player.getNextGameGuid();