[40K] Implemented Nexos

Mage/src/main/java/mage/abilities/mana/conditional/XCostManaCondition.java

@@ -0,0 +1,36 @@
+package mage.abilities.mana.conditional;
+
+import mage.abilities.Ability;
+import mage.abilities.costs.Cost;
+import mage.abilities.costs.mana.ManaCosts;
+import mage.abilities.costs.mana.VariableManaCost;
+import mage.game.Game;
+
+import java.util.UUID;
+
+/**
+ * @author TheElk801
+ */
+public class XCostManaCondition extends ManaCondition {
+
+    /*
+    A “cost that contains {X}” may be a spell’s total cost, an activated ability’s cost, a suspend cost, or a cost you’re
+    asked to pay as part of the resolution of a spell or ability (such as Condescend). A spell’s total cost includes either
+    its mana cost (printed in the upper right corner) or its alternative cost (such as flashback), as well as any additional
+    costs (such as kicker). If it’s something you can spend mana on, it’s a cost. If that cost includes the {X} symbol in it,
+    you can spend mana generated by Rosheen on that cost. (2017-11-17)
+     */
+    @Override
+    public boolean apply(Game game, Ability source, UUID originalId, Cost costToPay) {
+        boolean result;
+        if (costToPay instanceof ManaCosts) {
+            result = !((ManaCosts<?>) costToPay).getVariableCosts().isEmpty();
+        } else {
+            result = costToPay instanceof VariableManaCost;
+        }
+        if (!result && game != null && game.inCheckPlayableState()) {
+            return true; // TODO: Check the card if there are related abilities with {X} costs.
+        }
+        return result;
+    }
+}