Reworked Assist ability (#768)

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

@@ -5,21 +5,37 @@ import mage.abilities.Ability;
 import mage.abilities.SpecialAction;
 import mage.abilities.common.SimpleStaticAbility;
 import mage.abilities.costs.Cost;
+import mage.abilities.costs.mana.ActivationManaAbilityStep;
 import mage.abilities.costs.mana.AlternateManaPaymentAbility;
 import mage.abilities.costs.mana.ManaCost;
 import mage.abilities.effects.OneShotEffect;
+import mage.abilities.mana.ManaOptions;
 import mage.constants.*;
 import mage.filter.FilterPlayer;
 import mage.game.Game;
+import mage.game.stack.Spell;
 import mage.players.ManaPool;
 import mage.players.Player;
 import mage.target.Target;
 import mage.target.TargetPlayer;
 import mage.util.ManaUtil;
 
-/*
- * @author emerald000
+import java.util.UUID;
+
+/**
+ * 702.131. Assist
+ * <p>
+ * 702.131a Assist is a static ability that modifies the rules of paying for the spell with assist (see rules 601.2g-h).
+ * If the total cost to cast a spell with assist includes a generic mana component, before you activate mana
+ * abilities while casting it, you may choose another player. That player has a chance to activate mana abilities.
+ * Once that player chooses not to activate any more mana abilities, you have a chance to activate mana abilities.
+ * Before you begin to pay the total cost of the spell, the player you chose may pay for any amount of the generic
+ * mana in the spell’s total cost.
+ *
+ * @author emerald000, JayDi85
  */
+
+
 public class AssistAbility extends SimpleStaticAbility implements AlternateManaPaymentAbility {
 
     private static final FilterPlayer filter = new FilterPlayer("another player");
@@ -29,7 +45,7 @@ public class AssistAbility extends SimpleStaticAbility implements AlternateManaP
     }
 
     public AssistAbility() {
-        super(Zone.STACK, null);
+        super(Zone.ALL, null);
         this.setRuleAtTheTop(true);
     }
 
@@ -42,14 +58,24 @@ public class AssistAbility extends SimpleStaticAbility implements AlternateManaP
         return new AssistAbility(this);
     }
 
+    @Override
+    public String getRule() {
+        return "Assist <i>(Another player can help pay the generic mana of this spell's cost.)</i>";
+    }
+
+    @Override
+    public ActivationManaAbilityStep useOnActivationManaAbilityStep() {
+        return ActivationManaAbilityStep.BEFORE;
+    }
+
     @Override
     public void addSpecialAction(Ability source, Game game, ManaCost unpaid) {
         Player controller = game.getPlayer(source.getControllerId());
         if (controller != null
                 && source.getAbilityType() == AbilityType.SPELL
                 && unpaid.getMana().getGeneric() >= 1
-                && game.getState().getValue(source.getSourceId().toString() + game.getState().getZoneChangeCounter(source.getSourceId())) == null) {
-            SpecialAction specialAction = new AssistSpecialAction(unpaid);
+                && game.getState().getValue(source.getSourceId().toString() + game.getState().getZoneChangeCounter(source.getSourceId()) + "_assisted") == null) {
+            SpecialAction specialAction = new AssistSpecialAction(unpaid, this);
             specialAction.setControllerId(source.getControllerId());
             specialAction.setSourceId(source.getSourceId());
             Target target = new TargetPlayer(1, 1, true, filter);
@@ -61,15 +87,47 @@ public class AssistAbility extends SimpleStaticAbility implements AlternateManaP
     }
 
     @Override
-    public String getRule() {
-        return "Assist <i>(Another player can help pay the generic mana of this spell's cost.)</i>";
+    public ManaOptions getManaOptions(Ability source, Game game, ManaCost unpaid) {
+        ManaOptions options = new ManaOptions();
+        if (unpaid.getMana().getGeneric() == 0) {
+            // nothing to pay
+            return options;
+        }
+
+        // AI can't use assist (can't ask another player to help), maybe in teammode it can be enabled, but tests must works all the time
+        Player controller = game.getPlayer(source.getControllerId());
+        if (controller != null && !controller.isTestMode() && !controller.isHuman()) {
+            return options;
+        }
+
+        // search opponents who can help with generic pay
+        int opponentCanPayMax = 0;
+        for (UUID opponentId : game.getOpponents(source.getControllerId())) {
+            Player opponent = game.getPlayer(opponentId);
+            if (opponent != null) {
+                // basic and pool, but no coditional mana
+                ManaOptions availableMana = opponent.getManaAvailable(game);
+                availableMana.addMana(opponent.getManaPool().getMana());
+                for (Mana mana : availableMana) {
+                    if (mana.count() > 0) {
+                        opponentCanPayMax = Math.max(opponentCanPayMax, mana.count());
+                    }
+                }
+            }
+        }
+
+        if (opponentCanPayMax > 0) {
+            options.addMana(Mana.GenericMana(Math.min(unpaid.getMana().getGeneric(), opponentCanPayMax)));
+        }
+
+        return options;
     }
 }
 
 class AssistSpecialAction extends SpecialAction {
 
-    AssistSpecialAction(ManaCost unpaid) {
-        super(Zone.ALL, true);
+    AssistSpecialAction(ManaCost unpaid, AlternateManaPaymentAbility manaAbility) {
+        super(Zone.ALL, manaAbility);
         setRuleVisible(false);
         this.addEffect(new AssistEffect(unpaid));
     }
@@ -108,17 +166,28 @@ class AssistEffect extends OneShotEffect {
     public boolean apply(Game game, Ability source) {
         Player controller = game.getPlayer(source.getControllerId());
         Player targetPlayer = game.getPlayer(this.getTargetPointer().getFirst(game, source));
-        if (controller != null && targetPlayer != null) {
-            int amountToPay = targetPlayer.announceXMana(0, unpaid.getMana().getGeneric(), "How much mana to pay?", game, source);
+        Spell spell = game.getStack().getSpell(source.getSourceId());
+        if (controller != null && spell != null && targetPlayer != null) {
+            // AI can't assist other players, maybe for teammates only (but tests must work as normal)
+            int amountToPay = 0;
+            if (targetPlayer.isHuman() || targetPlayer.isTestMode()) {
+                amountToPay = targetPlayer.announceXMana(0, unpaid.getMana().getGeneric(),
+                        "How much mana to pay as assist for " + controller.getName() + "?", game, source);
+            }
+
             if (amountToPay > 0) {
                 Cost cost = ManaUtil.createManaCost(amountToPay, false);
                 if (cost.pay(source, game, source.getSourceId(), targetPlayer.getId(), false)) {
                     ManaPool manaPool = controller.getManaPool();
                     manaPool.addMana(Mana.ColorlessMana(amountToPay), game, source);
-                    manaPool.unlockManaType(ManaType.COLORLESS);
-                    game.informPlayers(targetPlayer.getLogName() + " paid {" + amountToPay + "}.");
-                    game.getState().setValue(source.getSourceId().toString() + game.getState().getZoneChangeCounter(source.getSourceId()), true);
+                    manaPool.unlockManaType(ManaType.COLORLESS); // it's unlock mana for one use/click, but it can gives more
+                    game.informPlayers(targetPlayer.getLogName() + " paid {" + amountToPay + "} for " + controller.getLogName());
+                    game.getState().setValue(source.getSourceId().toString() + game.getState().getZoneChangeCounter(source.getSourceId()) + "_assisted", true);
                 }
+
+                // assist must be used before activating mana abilities, so no need to switch step after usage
+                // (mana and other special abilities can be used after assist)
+                //spell.setCurrentActivatingManaAbilitiesStep(ActivationManaAbilityStep.NORMAL);
             }
             return true;
         }