Implement Mayhem mechanic (#13877)

Mage.Sets/src/mage/sets/MarvelsSpiderMan.java

@@ -4,15 +4,11 @@ import mage.cards.ExpansionSet;
 import mage.constants.Rarity;
 import mage.constants.SetType;
 
-import java.util.Arrays;
-import java.util.List;
-
 /**
  * @author TheElk801
  */
 public final class MarvelsSpiderMan extends ExpansionSet {
 
-    private static final List<String> unfinished = Arrays.asList("Electro's Bolt", "Spider-Islanders");
     private static final MarvelsSpiderMan instance = new MarvelsSpiderMan();
 
     public static MarvelsSpiderMan getInstance() {
@@ -98,7 +94,5 @@ public final class MarvelsSpiderMan extends ExpansionSet {
         cards.add(new SetCardInfo("Web-Warriors", 203, Rarity.UNCOMMON, mage.cards.w.WebWarriors.class, NON_FULL_USE_VARIOUS));
         cards.add(new SetCardInfo("Whoosh!", 48, Rarity.COMMON, mage.cards.w.Whoosh.class));
         cards.add(new SetCardInfo("Wild Pack Squad", 23, Rarity.COMMON, mage.cards.w.WildPackSquad.class));
-
-        cards.removeIf(setCardInfo -> unfinished.contains(setCardInfo.getName()));
     }
 }

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

@@ -0,0 +1,89 @@
+package org.mage.test.cards.abilities.keywords;
+
+import mage.constants.PhaseStep;
+import mage.constants.Zone;
+import org.junit.Assert;
+import org.junit.Test;
+import org.mage.test.serverside.base.CardTestPlayerBase;
+
+/**
+ * @author TheElk801
+ */
+public class MayhemTest extends CardTestPlayerBase {
+
+    private static final String islanders = "Spider-Islanders";
+
+    @Test
+    public void testCastRegular() {
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 4);
+        addCard(Zone.HAND, playerA, islanders);
+
+        castSpell(1, PhaseStep.PRECOMBAT_MAIN, playerA, islanders);
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+
+        assertPermanentCount(playerA, islanders, 1);
+    }
+
+    private static final String imp = "Putrid Imp";
+
+    @Test
+    public void testCastDiscarded() {
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 2);
+        addCard(Zone.BATTLEFIELD, playerA, imp);
+        addCard(Zone.HAND, playerA, islanders);
+
+        activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Discard");
+        setChoice(playerA, islanders);
+        castSpell(1, PhaseStep.POSTCOMBAT_MAIN, playerA, islanders + " with Mayhem");
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+
+        assertPermanentCount(playerA, islanders, 1);
+    }
+
+    @Test
+    public void testCantCastGraveyard() {
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 2);
+        addCard(Zone.GRAVEYARD, playerA, islanders);
+
+        castSpell(1, PhaseStep.PRECOMBAT_MAIN, playerA, islanders + " with Mayhem");
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        try {
+            execute();
+        } catch (Throwable e) {
+            Assert.assertEquals(
+                    "Should fail to be able to cast " + islanders + " with mayhem as it wasn't discarded this turn",
+                    "Can't find ability to activate command: Cast " + islanders + " with Mayhem", e.getMessage()
+            );
+        }
+    }
+
+    @Test
+    public void testCantCastDiscardedPreviously() {
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 2);
+        addCard(Zone.BATTLEFIELD, playerA, imp);
+        addCard(Zone.HAND, playerA, islanders);
+
+        activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Discard");
+        setChoice(playerA, islanders);
+        castSpell(3, PhaseStep.POSTCOMBAT_MAIN, playerA, islanders + " with Mayhem");
+
+        setStrictChooseMode(true);
+        setStopAt(3, PhaseStep.END_TURN);
+        try {
+            execute();
+        } catch (Throwable e) {
+            Assert.assertEquals(
+                    "Should fail to be able to cast " + islanders + " with mayhem as it wasn't discarded this turn",
+                    "Can't find ability to activate command: Cast " + islanders + " with Mayhem", e.getMessage()
+            );
+        }
+    }
+}

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

@@ -1,16 +1,19 @@
 package mage.abilities.keyword;
 
-import mage.ApprovingObject;
 import mage.MageIdentifier;
+import mage.MageObjectReference;
 import mage.abilities.SpellAbility;
 import mage.abilities.costs.mana.ManaCostsImpl;
 import mage.cards.Card;
 import mage.constants.SpellAbilityType;
+import mage.constants.WatcherScope;
 import mage.constants.Zone;
 import mage.game.Game;
-import mage.players.Player;
-import mage.watchers.common.CastSpellLastTurnWatcher;
+import mage.game.events.DiscardedCardsEvent;
+import mage.game.events.GameEvent;
+import mage.watchers.Watcher;
 
+import java.util.HashSet;
 import java.util.Set;
 import java.util.UUID;
 
@@ -33,9 +36,9 @@ public class MayhemAbility extends SpellAbility {
         this.clearManaCosts();
         this.clearManaCostsToPay();
         this.addCost(new ManaCostsImpl<>(manaString));
-
+        this.addWatcher(new MayhemWatcher());
         this.setRuleAtTheTop(true);
-        this.rule = "Surge " + manaString +
+        this.rule = "Mayhem " + manaString +
                 " <i>(You may cast this card from your graveyard for " + manaString +
                 " if you discarded it this turn. Timing rules still apply.)</i>";
     }
@@ -47,7 +50,10 @@ public class MayhemAbility extends SpellAbility {
 
     @Override
     public ActivationStatus canActivate(UUID playerId, Game game) {
-        // TODO: Implement this
+        if (!Zone.GRAVEYARD.match(game.getState().getZone(getSourceId()))
+                || !MayhemWatcher.checkCard(getSourceId(), game)) {
+            return ActivationStatus.getFalse();
+        }
         return super.canActivate(playerId, game);
     }
 
@@ -69,5 +75,38 @@ public class MayhemAbility extends SpellAbility {
     public String getRule() {
         return rule;
     }
-
+}
+
+class MayhemWatcher extends Watcher {
+
+    private final Set<MageObjectReference> set = new HashSet<>();
+
+    MayhemWatcher() {
+        super(WatcherScope.GAME);
+    }
+
+    @Override
+    public void watch(GameEvent event, Game game) {
+        if (event.getType() != GameEvent.EventType.DISCARDED_CARDS) {
+            return;
+        }
+        for (Card card : ((DiscardedCardsEvent) event).getDiscardedCards().getCards(game)) {
+            set.add(new MageObjectReference(card, game));
+        }
+    }
+
+    @Override
+    public void reset() {
+        super.reset();
+        set.clear();
+    }
+
+    static boolean checkCard(UUID cardId, Game game) {
+        return game
+                .getState()
+                .getWatcher(MayhemWatcher.class)
+                .set
+                .stream()
+                .anyMatch(mor -> mor.refersTo(cardId, game));
+    }
 }