refactor: improved search in stack

Mage.Server.Plugins/Mage.Player.AI.MA/src/mage/player/ai/ComputerPlayer6.java

@@ -398,7 +398,10 @@ public class ComputerPlayer6 extends ComputerPlayer {
     }
 
     protected void resolve(SimulationNode2 node, int depth, Game game) {
-        StackObject stackObject = game.getStack().getFirst();
+        StackObject stackObject = game.getStack().getFirstOrNull();
+        if (stackObject == null) {
+            throw new IllegalStateException("Catch empty stack on resolve (something wrong with sim code)");
+        }
         if (stackObject instanceof StackAbility) {
             // AI hint for search effects (calc all possible cards for best score)
             SearchEffect effect = getSearchEffect((StackAbility) stackObject);

Mage.Server.Plugins/Mage.Player.Human/src/mage/player/human/HumanPlayer.java

@@ -638,8 +638,8 @@ public class HumanPlayer extends PlayerImpl {
             // Check check if the spell being paid for cares about the color of mana being paid
             // See: https://github.com/magefree/mage/issues/9070
             boolean caresAboutManaColor = false;
-            if (!game.getStack().isEmpty() && game.getStack().getFirst() instanceof Spell) {
+            if (game.getStack().getFirstOrNull() instanceof Spell) {
-                Spell spellBeingCast = (Spell) game.getStack().getFirst();
+                Spell spellBeingCast = (Spell) game.getStack().getFirstOrNull();
                 if (!spellBeingCast.isResolving() && spellBeingCast.getControllerId().equals(this.getId())) {
                     CardImpl card = (CardImpl) game.getCard(spellBeingCast.getSourceId());
                     caresAboutManaColor = card.caresAboutManaColor(game);

Mage.Sets/src/mage/cards/a/AstralDrift.java

@@ -68,10 +68,7 @@ class AstralDriftTriggeredAbility extends TriggeredAbilityImpl {
 
     @Override
     public boolean checkTrigger(GameEvent event, Game game) {
-        if (game.getState().getStack().isEmpty()) {
+        StackObject item = game.getState().getStack().getFirstOrNull();
-            return false;
-        }
-        StackObject item = game.getState().getStack().getFirst();
         if (!(item instanceof StackAbility
                 && item.getStackAbility() instanceof CyclingAbility)) {
             return false;

Mage.Sets/src/mage/cards/c/CobraTrap.java

@@ -78,11 +78,9 @@ class CobraTrapWatcher extends Watcher {
         if (event.getType() == GameEvent.EventType.DESTROYED_PERMANENT) {
             Permanent perm = game.getPermanentOrLKIBattlefield(event.getTargetId()); // can regenerate or be indestructible
             if (perm != null && !perm.isCreature(game)) {
-                if (!game.getStack().isEmpty()) {
+                StackObject spell = game.getStack().getStackObject(event.getSourceId());
-                    StackObject spell = game.getStack().getStackObject(event.getSourceId());
+                if (spell != null && game.getOpponents(perm.getControllerId()).contains(spell.getControllerId())) {
-                    if (spell != null && game.getOpponents(perm.getControllerId()).contains(spell.getControllerId())) {
+                    players.add(perm.getControllerId());
-                        players.add(perm.getControllerId());
-                    }
                 }
             }
         }

Mage.Sets/src/mage/cards/r/RainOfGore.java

@@ -1,7 +1,5 @@
-
 package mage.cards.r;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.common.SimpleStaticAbility;
 import mage.abilities.effects.ReplacementEffectImpl;
@@ -10,20 +8,20 @@ import mage.cards.CardSetInfo;
 import mage.constants.CardType;
 import mage.constants.Duration;
 import mage.constants.Outcome;
-import mage.constants.Zone;
 import mage.game.Game;
 import mage.game.events.GameEvent;
 import mage.game.stack.StackObject;
 import mage.players.Player;
 
+import java.util.UUID;
+
 /**
- *
  * @author LevelX2
  */
 public final class RainOfGore extends CardImpl {
 
     public RainOfGore(UUID ownerId, CardSetInfo setInfo) {
-        super(ownerId,setInfo,new CardType[]{CardType.ENCHANTMENT},"{B}{R}");
+        super(ownerId, setInfo, new CardType[]{CardType.ENCHANTMENT}, "{B}{R}");
 
 
         // If a spell or ability would cause its controller to gain life, that player loses that much life instead.
@@ -71,13 +69,10 @@ class RainOfGoreEffect extends ReplacementEffectImpl {
     public boolean checksEventType(GameEvent event, Game game) {
         return event.getType() == GameEvent.EventType.GAIN_LIFE;
     }
-    
+
     @Override
     public boolean applies(GameEvent event, Ability source, Game game) {
-        if (!game.getStack().isEmpty()) {
+        StackObject stackObject = game.getStack().getFirstOrNull();
-            StackObject stackObject = game.getStack().getFirst();
+        return stackObject != null && stackObject.isControlledBy(event.getPlayerId());
-            return stackObject.isControlledBy(event.getPlayerId());
-        }
-        return false;
     }
 }

Mage.Sets/src/mage/cards/s/SoulSculptor.java

@@ -120,13 +120,8 @@ enum SoulSculptorCondition implements Condition {
 
     @Override
     public boolean apply(Game game, Ability source) {
-        if (!game.getStack().isEmpty()) {
+        StackObject stackObject = game.getStack().getFirstOrNull();
-            StackObject stackObject = game.getStack().getFirst();
+        return stackObject != null && !stackObject.getCardType(game).contains(CardType.CREATURE);
-            if (stackObject != null) {
-                return !stackObject.getCardType(game).contains(CardType.CREATURE);
-            }
-        }
-        return true;
     }
 
     @Override

Mage.Sets/src/mage/cards/s/SoulfireGrandMaster.java

@@ -21,6 +21,7 @@ import mage.game.Game;
 import mage.game.events.GameEvent;
 import mage.game.events.ZoneChangeEvent;
 import mage.game.stack.Spell;
+import mage.game.stack.StackObject;
 import mage.players.Player;
 
 import java.util.UUID;
@@ -94,18 +95,22 @@ class SoulfireGrandMasterCastFromHandReplacementEffect extends ReplacementEffect
 
     @Override
     public boolean replaceEvent(GameEvent event, Ability source, Game game) {
-        Spell spell = (Spell) game.getStack().getFirst();
+        StackObject stackObject = game.getStack().getFirstOrNull();
-        if (!spell.isCopy() && !spell.isCountered()) {
+        if (stackObject instanceof Spell) {
-            Card sourceCard = game.getCard(spellId);
+            Spell spell = (Spell) stackObject;
-            if (sourceCard != null && Zone.STACK.equals(game.getState().getZone(spellId))) {
+            if (!spell.isCopy() && !spell.isCountered()) {
-                Player player = game.getPlayer(sourceCard.getOwnerId());
+                Card sourceCard = game.getCard(spellId);
-                if (player != null) {
+                if (sourceCard != null && Zone.STACK.equals(game.getState().getZone(spellId))) {
-                    player.moveCards(sourceCard, Zone.HAND, source, game);
+                    Player player = game.getPlayer(sourceCard.getOwnerId());
-                    discard();
+                    if (player != null) {
-                    return true;
+                        player.moveCards(sourceCard, Zone.HAND, source, game);
+                        discard();
+                        return true;
+                    }
                 }
             }
         }
+
         return false;
     }
 
@@ -134,8 +139,8 @@ class SoulfireGrandMasterCastFromHandReplacementEffect extends ReplacementEffect
             if (zEvent.getFromZone() == Zone.STACK
                     && zEvent.getToZone() == Zone.GRAVEYARD
                     && event.getTargetId().equals(spellId)) {
-                if (game.getStack().getFirst() instanceof Spell) {
+                if (game.getStack().getFirstOrNull() instanceof Spell) {
-                    Card cardOfSpell = ((Spell) game.getStack().getFirst()).getCard();
+                    Card cardOfSpell = ((Spell) game.getStack().getFirstOrNull()).getCard();
                     return cardOfSpell.getMainCard().getId().equals(spellId);
                 }
             }

Mage.Sets/src/mage/cards/t/TheTwelfthDoctor.java

@@ -99,12 +99,10 @@ enum FirstSpellCastFromNotHandEachTurnCondition implements Condition {
 
     @Override
     public boolean apply(Game game, Ability source) {
-        if (game.getStack().isEmpty()) {
-            return false;
-        }
         TheTwelfthDoctorWatcher watcher = game.getState().getWatcher(TheTwelfthDoctorWatcher.class);
-        StackObject so = game.getStack().getFirst();
+        StackObject so = game.getStack().getFirstOrNull();
-        return watcher != null
+        return so != null
+                && watcher != null
                 && TheTwelfthDoctorWatcher.checkSpell(so, game);
     }
 }

Mage.Sets/src/mage/cards/v/ValiantRescuer.java

@@ -74,12 +74,11 @@ class ValiantRescuerTriggeredAbility extends TriggeredAbilityImpl {
         ValiantRescuerWatcher watcher = game.getState().getWatcher(ValiantRescuerWatcher.class);
         if (watcher == null
                 || !watcher.checkSpell(event.getPlayerId(), event.getSourceId())
-                || game.getState().getStack().isEmpty()
                 || !event.getPlayerId().equals(this.getControllerId())
                 || event.getSourceId().equals(this.getSourceId())) {
             return false;
         }
-        StackObject item = game.getState().getStack().getFirst();
+        StackObject item = game.getState().getStack().getFirstOrNull();
         return item instanceof StackAbility
                 && item.getStackAbility() instanceof CyclingAbility;
     }
@@ -106,11 +105,10 @@ class ValiantRescuerWatcher extends Watcher {
 
     @Override
     public void watch(GameEvent event, Game game) {
-        if (event.getType() != GameEvent.EventType.ACTIVATED_ABILITY
+        if (event.getType() != GameEvent.EventType.ACTIVATED_ABILITY) {
-                || game.getState().getStack().isEmpty()) {
             return;
         }
-        StackObject item = game.getState().getStack().getFirst();
+        StackObject item = game.getState().getStack().getFirstOrNull();
         if (item instanceof StackAbility
                 && item.getStackAbility() instanceof CyclingAbility) {
             playerMap.computeIfAbsent(event.getPlayerId(), u -> new HashMap<>());

Mage.Sets/src/mage/cards/w/WildMagicSorcerer.java

@@ -2,7 +2,10 @@ package mage.cards.w;
 
 import mage.MageInt;
 import mage.MageObjectReference;
+import mage.abilities.Ability;
 import mage.abilities.common.SimpleStaticAbility;
+import mage.abilities.condition.Condition;
+import mage.abilities.effects.ContinuousEffectImpl;
 import mage.abilities.keyword.CascadeAbility;
 import mage.cards.CardImpl;
 import mage.cards.CardSetInfo;
@@ -11,14 +14,12 @@ import mage.game.Game;
 import mage.game.events.GameEvent;
 import mage.game.stack.Spell;
 import mage.game.stack.StackObject;
+import mage.players.Player;
 import mage.watchers.Watcher;
+
 import java.util.HashMap;
 import java.util.Map;
 import java.util.UUID;
-import mage.abilities.Ability;
-import mage.abilities.condition.Condition;
-import mage.abilities.effects.ContinuousEffectImpl;
-import mage.players.Player;
 
 /**
  * @author TheElk801
@@ -35,7 +36,7 @@ public final class WildMagicSorcerer extends CardImpl {
 
         // The first spell you cast from exile each turn has cascade.
         this.addAbility(new SimpleStaticAbility(
-                new WildMagicSorcererGainCascadeFirstSpellCastFromExileEffect()),
+                        new WildMagicSorcererGainCascadeFirstSpellCastFromExileEffect()),
                 new WildMagicSorcererWatcher());
     }
 
@@ -96,12 +97,10 @@ enum FirstSpellCastFromExileEachTurnCondition implements Condition {
 
     @Override
     public boolean apply(Game game, Ability source) {
-        if (game.getStack().isEmpty()) {
-            return false;
-        }
         WildMagicSorcererWatcher watcher = game.getState().getWatcher(WildMagicSorcererWatcher.class);
-        StackObject so = game.getStack().getFirst();
+        StackObject so = game.getStack().getFirstOrNull();
-        return watcher != null
+        return so != null
+                && watcher != null
                 && WildMagicSorcererWatcher.checkSpell(so, game);
     }
 }

Mage.Tests/src/test/java/org/mage/test/cards/abilities/keywords/DisguiseTest.java

@@ -55,7 +55,7 @@ public class DisguiseTest extends CardTestPlayerBase {
         castSpell(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Dog Walker using Disguise");
         runCode("face up on stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, (info, player, game) -> {
             Assert.assertEquals("stack, server - can't find spell", 1, currentGame.getStack().size());
-            SpellAbility spellAbility = (SpellAbility) currentGame.getStack().getFirst().getStackAbility();
+            SpellAbility spellAbility = (SpellAbility) currentGame.getStack().getFirstOrNull().getStackAbility();
             Assert.assertEquals("stack, server - can't find spell", "Cast Dog Walker using Disguise", spellAbility.getName());
             CardView spellView = getGameView(playerA).getStack().values().stream().findFirst().orElse(null);
             Assert.assertNotNull("stack, client: can't find spell", spellView);

Mage.Tests/src/test/java/org/mage/test/cards/abilities/keywords/DisturbTest.java

@@ -40,7 +40,7 @@ public class DisturbTest extends CardTestPlayerBase {
         checkStackObject("on stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, "Cast Hook-Haunt Drifter using Disturb", 1);
         runCode("check stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, (info, player, game) -> {
             // Stack must contain another card side, so spell/card characteristics must be diff from main side (only mana value is same)
-            Spell spell = (Spell) game.getStack().getFirst();
+            Spell spell = (Spell) game.getStack().getFirstOrNull();
             Assert.assertEquals("Hook-Haunt Drifter", spell.getName());
             Assert.assertEquals(1, spell.getCardType(game).size());
             Assert.assertEquals(CardType.CREATURE, spell.getCardType(game).get(0));
@@ -91,7 +91,7 @@ public class DisturbTest extends CardTestPlayerBase {
         checkStackObject("on stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, "Cast Waildrifter using Disturb", 1);
         runCode("check stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, (info, player, game) -> {
             // Stack must contain another card side, so spell/card characteristics must be diff from main side (only mana value is same)
-            Spell spell = (Spell) game.getStack().getFirst();
+            Spell spell = (Spell) game.getStack().getFirstOrNull();
             Assert.assertEquals("Waildrifter", spell.getName());
             Assert.assertEquals(1, spell.getCardType(game).size());
             Assert.assertEquals(CardType.CREATURE, spell.getCardType(game).get(0));
@@ -187,7 +187,7 @@ public class DisturbTest extends CardTestPlayerBase {
         // cast with disturb
         activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Cast Hook-Haunt Drifter using Disturb");
         runCode("check stack", 1, PhaseStep.PRECOMBAT_MAIN, playerA, (info, player, game) -> {
-            Spell spell = (Spell) game.getStack().getFirst();
+            Spell spell = (Spell) game.getStack().getFirstOrNull();
             Assert.assertEquals("mana value must be from main side", 2, spell.getManaValue());
             Assert.assertEquals("mana cost to pay must be modified", "{U}", spell.getSpellAbility().getManaCostsToPay().getText());
         });

Mage.Tests/src/test/java/org/mage/test/player/TestPlayer.java

@@ -334,11 +334,8 @@ public class TestPlayer implements Player {
             return true;
         } else if (groups[2].startsWith("spellOnTopOfStack=")) {
             String spellOnTopOFStack = groups[2].substring(18);
-            if (!game.getStack().isEmpty()) {
+            StackObject stackObject = game.getStack().getFirstOrNull();
-                StackObject stackObject = game.getStack().getFirst();
+            return stackObject != null && stackObject.getStackAbility().toString().contains(spellOnTopOFStack);
-                return stackObject != null && stackObject.getStackAbility().toString().contains(spellOnTopOFStack);
-            }
-            return false;
         } else if (groups[2].startsWith("manaInPool=")) {
             String manaInPool = groups[2].substring(11);
             int amountOfMana = Integer.parseInt(manaInPool);

Mage/src/main/java/mage/abilities/SpecialAction.java

@@ -53,11 +53,9 @@ public abstract class SpecialAction extends ActivatedAbilityImpl {
         if (isManaAction()) {
             // limit play mana abilities by steps
             int currentStepOrder = 0;
-            if (!game.getStack().isEmpty()) {
+            StackObject stackObject = game.getStack().getFirstOrNull();
-                StackObject stackObject = game.getStack().getFirst();
+            if (stackObject instanceof Spell) {
-                if (stackObject instanceof Spell) {
+                currentStepOrder = ((Spell) stackObject).getCurrentActivatingManaAbilitiesStep().getStepOrder();
-                    currentStepOrder = ((Spell) stackObject).getCurrentActivatingManaAbilitiesStep().getStepOrder();
-                }
             }
             if (currentStepOrder > manaAbility.useOnActivationManaAbilityStep().getStepOrder()) {
                 return ActivationStatus.getFalse();

Mage/src/main/java/mage/abilities/common/CycleAllTriggeredAbility.java

@@ -31,10 +31,7 @@ public class CycleAllTriggeredAbility extends TriggeredAbilityImpl {
 
     @Override
     public boolean checkTrigger(GameEvent event, Game game) {
-        if (game.getState().getStack().isEmpty()) {
+        StackObject item = game.getState().getStack().getFirstOrNull();
-            return false;
-        }
-        StackObject item = game.getState().getStack().getFirst();
         return item instanceof StackAbility
                 && item.getStackAbility() instanceof CyclingAbility;
     }

Mage/src/main/java/mage/abilities/common/CycleControllerTriggeredAbility.java

@@ -42,12 +42,11 @@ public class CycleControllerTriggeredAbility extends TriggeredAbilityImpl {
 
     @Override
     public boolean checkTrigger(GameEvent event, Game game) {
-        if (game.getState().getStack().isEmpty()
+        if (!event.getPlayerId().equals(this.getControllerId())
-                || !event.getPlayerId().equals(this.getControllerId())
                 || (event.getSourceId().equals(this.getSourceId()) && excludeSource)) {
             return false;
         }
-        StackObject item = game.getState().getStack().getFirst();
+        StackObject item = game.getState().getStack().getFirstOrNull();
         return item instanceof StackAbility
                 && item.getStackAbility() instanceof CyclingAbility;
     }

Mage/src/main/java/mage/abilities/dynamicvalue/common/SunburstCount.java

@@ -18,25 +18,24 @@ public enum SunburstCount implements DynamicValue {
     @Override
     public int calculate(Game game, Ability sourceAbility, Effect effect) {
         int count = 0;
-        if (!game.getStack().isEmpty()) {
+
-            StackObject spell = game.getStack().getFirst();
+        StackObject spell = game.getStack().getFirstOrNull();
-            if (spell instanceof Spell && ((Spell) spell).getSourceId().equals(sourceAbility.getSourceId())) {
+        if (spell instanceof Spell && spell.getSourceId().equals(sourceAbility.getSourceId())) {
-                Mana mana = ((Spell) spell).getSpellAbility().getManaCostsToPay().getUsedManaToPay();
+            Mana mana = ((Spell) spell).getSpellAbility().getManaCostsToPay().getUsedManaToPay();
-                if (mana.getBlack() > 0) {
+            if (mana.getBlack() > 0) {
-                    count++;
+                count++;
-                }
+            }
-                if (mana.getBlue() > 0) {
+            if (mana.getBlue() > 0) {
-                    count++;
+                count++;
-                }
+            }
-                if (mana.getGreen() > 0) {
+            if (mana.getGreen() > 0) {
-                    count++;
+                count++;
-                }
+            }
-                if (mana.getRed() > 0) {
+            if (mana.getRed() > 0) {
-                    count++;
+                count++;
-                }
+            }
-                if (mana.getWhite() > 0) {
+            if (mana.getWhite() > 0) {
-                    count++;
+                count++;
-                }
             }
         }
         return count;

Mage/src/main/java/mage/abilities/effects/ContinuousEffectImpl.java

@@ -513,13 +513,10 @@ public abstract class ContinuousEffectImpl extends EffectImpl implements Continu
         // If the top card of your library changes while you’re casting a spell, playing a land, or activating an ability,
         // you can’t look at the new top card until you finish doing so. This means that if you cast the top card of
         // your library, you can’t look at the next one until you’re done paying for that spell. (2019-05-03)
-        if (!game.getStack().isEmpty()) {
+        StackObject stackObject = game.getStack().getFirstOrNull();
-            StackObject stackObject = game.getStack().getFirst();
+        return !(stackObject instanceof Spell)
-            return !(stackObject instanceof Spell)
+                || !Zone.LIBRARY.equals(((Spell) stackObject).getFromZone())
-                    || !Zone.LIBRARY.equals(((Spell) stackObject).getFromZone())
+                || stackObject.getStackAbility().getManaCostsToPay().isPaid(); // mana payment finished
-                    || stackObject.getStackAbility().getManaCostsToPay().isPaid(); // mana payment finished
-        }
-        return true;
     }
 
     @Override

Mage/src/main/java/mage/abilities/mana/ActivatedManaAbilityImpl.java

@@ -44,19 +44,16 @@ public abstract class ActivatedManaAbilityImpl extends ActivatedAbilityImpl impl
     public ActivationStatus canActivate(UUID playerId, Game game) {
         // check if player is in the process of playing spell costs and they are no longer allowed to use
         // activated mana abilities (e.g. because they started to use improvise or convoke)
-        if (!game.getStack().isEmpty()) {
+        StackObject stackObject = game.getStack().getFirstOrNull();
-            StackObject stackObject = game.getStack().getFirst();
+        if (stackObject instanceof Spell) {
-            if (stackObject instanceof Spell) {
+            switch (((Spell) stackObject).getCurrentActivatingManaAbilitiesStep()) {
-                switch (((Spell) stackObject).getCurrentActivatingManaAbilitiesStep()) {
+                case BEFORE:
-                    case BEFORE:
+                case NORMAL:
-                    case NORMAL:
+                    break;
-                        break;
+                case AFTER:
-                    case AFTER:
+                    return ActivationStatus.getFalse();
-                        return ActivationStatus.getFalse();
-                }
             }
         }
-
         return super.canActivate(playerId, game);
     }
 

Mage/src/main/java/mage/game/stack/SpellStack.java

@@ -51,6 +51,16 @@ public class SpellStack extends ArrayDeque<StackObject> {
         }
     }
 
+    @Override
+    @Deprecated // must use getFirstOrNull instead
+    public StackObject getFirst() {
+        return super.getFirst();
+    }
+
+    public StackObject getFirstOrNull() {
+        return this.isEmpty() ? null : this.getFirst();
+    }
+
     public boolean remove(StackObject object, Game game) {
         for (StackObject spell : this) {
             if (spell.getId().equals(object.getId())) {