- Implemented some rudimentary mana ritual AI.

- Marked Dark Ritual as AI-playable. Other similar cards can probably now also use AI ManaRitual for this purpose.

forge-ai/src/main/java/forge/ai/SpecialCardAi.java

@@ -180,6 +180,31 @@ public class SpecialCardAi {
         }
     }
         
+    // Dark Ritual and other similar instants/sorceries that add mana to mana pool
+    public static class DarkRitualOrSimilar {
+        public static boolean consider(Player ai, SpellAbility sa) {
+            PhaseHandler ph = ai.getGame().getPhaseHandler();
+
+            if (!(ph.getPlayerTurn().equals(ai) && ph.is(PhaseType.MAIN2))) {
+                return false;
+            }
+
+            CardCollection manaSources = ComputerUtilMana.getAvailableMana(ai, true);
+            int numManaSrcs = manaSources.size();
+            int manaReceived = Integer.parseInt(sa.getParam("Amount"));
+            int selfCost = sa.getPayCosts().getCostMana() != null ? sa.getPayCosts().getCostMana().getMana().getCMC() : 0;
+            byte producedColor = MagicColor.fromName(sa.getParam("Produced"));
+
+            // try to determine the number of permanents we can cast with this
+            int numPerms = CardLists.filter(ai.getCardsIn(ZoneType.Hand), 
+                    Predicates.and(CardPredicates.Presets.NONLAND_PERMANENTS, CardPredicates.lessCMC(numManaSrcs - selfCost + manaReceived),
+                            Predicates.or(CardPredicates.isColorless(), CardPredicates.isColor(producedColor)))).size();
+
+            // TODO: this will probably still waste the card from time to time. Somehow improve detection of castable material.
+            return numPerms > 0;
+        }
+    }
+    
     // Desecration Demon
     public static class DesecrationDemon {
         private static final int demonSacThreshold = Integer.MAX_VALUE; // if we're in dire conditions, sac everything from worst to best hoping to find an answer

forge-ai/src/main/java/forge/ai/ability/ManaEffectAi.java

@@ -2,6 +2,7 @@ package forge.ai.ability;
 
 
 import forge.ai.ComputerUtil;
+import forge.ai.SpecialCardAi;
 import forge.ai.SpellAbilityAi;
 import forge.game.phase.PhaseType;
 import forge.game.player.Player;
@@ -11,6 +12,9 @@ public class ManaEffectAi extends SpellAbilityAi {
 
     @Override
     protected boolean canPlayAI(Player ai, SpellAbility sa) {
+        if ("ManaRitual".equals(sa.getParam("AILogic"))) {
+            return SpecialCardAi.DarkRitualOrSimilar.consider(ai, sa);
+        }
         if (ai.getGame().getPhaseHandler().is(PhaseType.MAIN2) && ComputerUtil.activateForCost(sa, ai)) {
             return true;
         }

forge-game/src/main/java/forge/game/card/CardPredicates.java

@@ -218,6 +218,15 @@ public final class CardPredicates {
         };
     } // getColor()
 
+    public static final Predicate<Card> isColorless() {
+        return new Predicate<Card>() {
+            @Override
+            public boolean apply(final Card c) {
+                return CardUtil.getColors(c).isColorless();
+            }
+        };
+    }
+
     public static final Predicate<Card> isEquippedBy(final String name) {
         return new Predicate<Card>() {
             @Override
@@ -463,6 +472,24 @@ public final class CardPredicates {
                 return c.isLand();
             }
         };
+        /**
+         * a Predicate<Card> to get all permanents.
+         */
+        public static final Predicate<Card> PERMANENTS = new Predicate<Card>() {
+            @Override
+            public boolean apply(Card c) {
+                return c.isPermanent();
+            }
+        };
+        /**
+         * a Predicate<Card> to get all nonland permanents.
+         */
+        public static final Predicate<Card> NONLAND_PERMANENTS = new Predicate<Card>() {
+            @Override
+            public boolean apply(Card c) {
+                return c.isPermanent() && !c.isLand();
+            }
+        };
 
         public static final Predicate<Card> hasFirstStrike = new Predicate<Card>() {
             @Override

forge-gui/res/cardsfolder/d/dark_ritual.txt

@@ -1,7 +1,6 @@
 Name:Dark Ritual
 ManaCost:B
 Types:Instant
-A:SP$ Mana | Cost$ B | Produced$ B | Amount$ 3 | SpellDescription$ Add {B}{B}{B} to your mana pool.
-SVar:RemAIDeck:True
+A:SP$ Mana | Cost$ B | Produced$ B | Amount$ 3 | AILogic$ ManaRitual | SpellDescription$ Add {B}{B}{B} to your mana pool.
 SVar:Picture:http://www.wizards.com/global/images/magic/general/dark_ritual.jpg
 Oracle:Add {B}{B}{B} to your mana pool.