[MOM] Implement Zephyr Singer

Mage/src/main/java/mage/abilities/keyword/ConvokeAbility.java

@@ -30,6 +30,7 @@ import mage.players.ManaPool;
 import mage.players.Player;
 import mage.target.Target;
 import mage.target.common.TargetControlledCreaturePermanent;
+import mage.watchers.common.ConvokeWatcher;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -79,6 +80,7 @@ public class ConvokeAbility extends SimpleStaticAbility implements AlternateMana
     public ConvokeAbility() {
         super(Zone.ALL, null); // all AlternateManaPaymentAbility must use ALL zone to calculate playable abilities
         this.setRuleAtTheTop(true);
+        this.addWatcher(new ConvokeWatcher());
         this.addHint(new ValueHint("Untapped creatures you control", new PermanentsOnBattlefieldCount(filterUntapped)));
     }
 

Mage/src/main/java/mage/filter/predicate/permanent/ConvokedSourcePredicate.java

@@ -0,0 +1,28 @@
+package mage.filter.predicate.permanent;
+
+import mage.MageObjectReference;
+import mage.filter.predicate.ObjectSourcePlayer;
+import mage.filter.predicate.ObjectSourcePlayerPredicate;
+import mage.game.Game;
+import mage.game.permanent.Permanent;
+import mage.watchers.common.ConvokeWatcher;
+
+/**
+ * @author TheElk801
+ */
+public enum ConvokedSourcePredicate implements ObjectSourcePlayerPredicate<Permanent> {
+    PERMANENT(-1),
+    SPELL(0);
+    private final int offset;
+
+    ConvokedSourcePredicate(int offset) {
+        this.offset = offset;
+    }
+
+    @Override
+    public boolean apply(ObjectSourcePlayer<Permanent> input, Game game) {
+        return ConvokeWatcher.checkConvoke(
+                new MageObjectReference(input.getSource(), offset), input.getObject(), game
+        );
+    }
+}

Mage/src/main/java/mage/watchers/common/ConvokeWatcher.java

@@ -16,11 +16,11 @@ import java.util.Set;
 /**
  * @author LevelX2
  */
-public class EachCreatureThatConvokedSourceWatcher extends Watcher {
+public class ConvokeWatcher extends Watcher {
 
     private final Map<MageObjectReference, Set<MageObjectReference>> convokingCreatures = new HashMap<>();
 
-    public EachCreatureThatConvokedSourceWatcher() {
+    public ConvokeWatcher() {
         super(WatcherScope.GAME);
     }
 
@@ -29,26 +29,28 @@ public class EachCreatureThatConvokedSourceWatcher extends Watcher {
         if (event.getType() != GameEvent.EventType.CONVOKED) {
             return;
         }
-
         Spell spell = game.getSpell(event.getSourceId());
         Permanent tappedCreature = game.getPermanentOrLKIBattlefield(event.getTargetId());
         if (spell == null || tappedCreature == null) {
             return;
         }
-
-        MageObjectReference convokedSpell = new MageObjectReference(spell.getSourceId(), game);
-        Set<MageObjectReference> creatures;
-        if (convokingCreatures.containsKey(convokedSpell)) {
-            creatures = convokingCreatures.get(convokedSpell);
-        } else {
-            creatures = new HashSet<>();
-            convokingCreatures.put(convokedSpell, creatures);
-        }
-        creatures.add(new MageObjectReference(tappedCreature, game));
+        convokingCreatures
+                .computeIfAbsent(new MageObjectReference(spell.getSourceId(), game), x -> new HashSet<>())
+                .add(new MageObjectReference(tappedCreature, game));
     }
 
-    public Set<MageObjectReference> getConvokingCreatures(MageObjectReference mor) {
-        return convokingCreatures.get(mor);
+    public static Set<MageObjectReference> getConvokingCreatures(MageObjectReference mor, Game game) {
+        return game
+                .getState()
+                .getWatcher(ConvokeWatcher.class)
+                .convokingCreatures
+                .get(mor);
+    }
+
+    public static boolean checkConvoke(MageObjectReference mor, Permanent permanent, Game game) {
+        return getConvokingCreatures(mor, game)
+                .stream()
+                .anyMatch(m -> m.refersTo(permanent, game));
     }
 
     @Override