Only deduct energy when elemental burst actually fires

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

@@ -327,6 +327,7 @@ public enum Type {
         public String srcKey, dstKey;
 
         public int skillID;
+        public int resistanceListID;
 
         public AbilityModifierAction[] actions;
         public AbilityModifierAction[] successActions;

src/main/java/emu/grasscutter/game/ability/Ability.java

@@ -2,6 +2,7 @@
 
 import emu.grasscutter.data.GameData;
 import emu.grasscutter.data.binout.AbilityData;
+import emu.grasscutter.data.binout.AbilityModifier.AbilityModifierAction;
 import emu.grasscutter.game.entity.GameEntity;
 import emu.grasscutter.game.player.Player;
 import emu.grasscutter.net.proto.AbilityStringOuterClass.AbilityString;
@@ -24,6 +25,7 @@ public class Ability {
     private static Map<String, Object2FloatMap<String>> abilitySpecialsModified = new HashMap<>();
 
     @Getter private int hash;
+    @Getter private Set<Integer> avatarSkillStartIds;
 
     public Ability(AbilityData data, GameEntity owner, Player playerOwner) {
         this.data = data;
@@ -44,6 +46,30 @@ public Ability(AbilityData data, GameEntity owner, Player playerOwner) {
         hash = Utils.abilityHash(data.abilityName);
 
         data.initialize();
+
+        //
+        // Collect skill IDs referenced by AvatarSkillStart modifier actions
+        // in onAbilityStart and in every modifier's onAdded action set.
+        // These skill IDs will be used by AbilityManager to determine whether
+        // an elemental burst has fired correctly.
+        //
+        avatarSkillStartIds = new HashSet<>();
+        if (data.onAbilityStart != null) {
+            avatarSkillStartIds.addAll(Arrays.stream(data.onAbilityStart)
+                                        .filter(action ->
+                                                action.type == AbilityModifierAction.Type.AvatarSkillStart)
+                                        .map(action -> action.skillID)
+                                        .toList());
+        }
+        avatarSkillStartIds.addAll(data.modifiers.values()
+                                        .stream()
+                                        .map(m -> (List<AbilityModifierAction>)(m.onAdded == null ?
+                                                                                Collections.emptyList() :
+                                                                                Arrays.asList(m.onAdded)))
+                                        .flatMap(List::stream)
+                                        .filter(action -> action.type == AbilityModifierAction.Type.AvatarSkillStart)
+                                        .map(action -> action.skillID)
+                                        .toList());
     }
 
     public static String getAbilityName(AbilityString abString) {

src/main/java/emu/grasscutter/game/ability/AbilityManager.java

@@ -21,8 +21,9 @@
 import emu.grasscutter.net.proto.ModifierActionOuterClass.ModifierAction;
 import emu.grasscutter.server.event.player.PlayerUseSkillEvent;
 import io.netty.util.concurrent.FastThreadLocalThread;
-import java.util.HashMap;
+import java.util.*;
 import java.util.concurrent.*;
+import java.util.function.Consumer;
 import lombok.Getter;
 
 public final class AbilityManager extends BasePlayerManager {
@@ -48,9 +49,56 @@ public final class AbilityManager extends BasePlayerManager {
     }
 
     @Getter private boolean abilityInvulnerable = false;
+    @Getter private Consumer<Integer> clearBurstEnergy;
+    private int burstCasterId;
+    private int burstSkillId;
 
     public AbilityManager(Player player) {
         super(player);
+        removePendingEnergyClear();
+    }
+
+    public void removePendingEnergyClear() {
+        this.clearBurstEnergy = null;
+        this.burstCasterId = 0;
+        this.burstSkillId = 0;
+    }
+
+    private void onPossibleElementalBurst(Ability ability, AbilityModifier modifier, int entityId) {
+        //
+        // Possibly clear avatar energy spent on elemental burst
+        // and set invulnerability.
+        //
+        // Problem: Burst can misfire occasionally, like hitting Q when
+        // dashing, doing E, or switching avatars. The client would
+        // still send EvtDoSkillSuccNotify, but the burst may not
+        // actually happen. We don't know when to clear avatar energy.
+        //
+        // When burst does happen, a number of AbilityInvokeEntry will
+        // come in. Use the Ability it references and search for any
+        // modifier with type=AvatarSkillStart, skillID=burst skill ID.
+        //
+        // If that is missing, search for modifier action that sets
+        // invulnerability as a fallback.
+        //
+        if (this.burstCasterId == 0) return;
+
+        boolean skillInvincibility = modifier.state == AbilityModifier.State.Invincible;
+        if (modifier.onAdded != null) {
+            skillInvincibility |= Arrays.stream(modifier.onAdded)
+                                            .filter(action ->
+                                                    action.type == AbilityModifierAction.Type.AttachAbilityStateResistance &&
+                                                    action.resistanceListID == 11002)
+                                            .toList().size() > 0;
+        }
+
+        if (this.clearBurstEnergy != null && this.burstCasterId == entityId &&
+                    (ability.getAvatarSkillStartIds().contains(this.burstSkillId) || skillInvincibility)) {
+            Grasscutter.getLogger().trace("Caster ID's {} burst successful, clearing energy and setting invulnerability", entityId);
+            this.abilityInvulnerable = true;
+            this.clearBurstEnergy.accept(entityId);
+            this.removePendingEnergyClear();
+        }
     }
 
     public static void registerHandlers() {
@@ -280,8 +328,12 @@ public void onSkillStart(Player player, int skillId, int casterId) {
             return;
         }
 
-        // Set the player as invulnerable.
-        this.abilityInvulnerable = true;
+        // Track this elemental burst to possibly clear avatar energy later.
+        this.clearBurstEnergy = (ignored) ->
+                player.getEnergyManager().handleEvtDoSkillSuccNotify(
+                        player.getSession(), skillId, casterId);
+        this.burstCasterId = casterId;
+        this.burstSkillId = skillId;
     }
 
     /**
@@ -454,6 +506,8 @@ private void handleModifierChange(AbilityInvokeEntry invoke) throws Exception {
                                 modifierData);
             }
 
+            onPossibleElementalBurst(instancedAbility, modifierData, invoke.getEntityId());
+
             AbilityModifierController modifier =
                     new AbilityModifierController(instancedAbility, instancedAbilityData, modifierData);
 

src/main/java/emu/grasscutter/game/managers/energy/EnergyManager.java

@@ -259,8 +259,14 @@ private void handleBurstCast(Avatar avatar, int skillId) {
             return;
         }
 
+        // Also reference AvatarSkillData in case the burst gets a different skill ID
+        // when the avatar is in a different state. For example, Wanderer's burst is
+        // 10755 usually but when he floats, it becomes 10753.
+        var skillData = GameData.getAvatarSkillDataMap().get(skillId);
+
         // If the cast skill was a burst, consume energy.
-        if (avatar.getSkillDepot() != null && skillId == avatar.getSkillDepot().getEnergySkill()) {
+        if ((avatar.getSkillDepot() != null && skillId == avatar.getSkillDepot().getEnergySkill()) ||
+                    (skillData != null && skillData.getCostElemVal() > 0)) {
             avatar.getAsEntity().clearEnergy(ChangeEnergyReason.CHANGE_ENERGY_REASON_SKILL_START);
         }
     }

src/main/java/emu/grasscutter/server/packet/recv/HandlerEvtDoSkillSuccNotify.java

@@ -21,7 +21,6 @@ public void handle(GameSession session, byte[] header, byte[] payload) throws Ex
 
         // Handle skill notify in other managers.
         player.getStaminaManager().handleEvtDoSkillSuccNotify(session, skillId, casterId);
-        player.getEnergyManager().handleEvtDoSkillSuccNotify(session, skillId, casterId);
         player.getQuestManager().queueEvent(QuestContent.QUEST_CONTENT_SKILL, skillId);
     }
 }