From ae5090a69a05d46a96e85e2282d3a3747ca9fec7 Mon Sep 17 00:00:00 2001
From: Agetian <stavdev@mail.ru>
Date: Tue, 4 Dec 2018 14:33:46 +0300
Subject: [PATCH] - More careful use of Buyback spells without Buyback.

---
 .../src/main/java/forge/ai/AiController.java  | 86 +++++++++++--------
 1 file changed, 50 insertions(+), 36 deletions(-)

diff --git a/forge-ai/src/main/java/forge/ai/AiController.java b/forge-ai/src/main/java/forge/ai/AiController.java
index 4b708ec5863..537a7666e93 100644
--- a/forge-ai/src/main/java/forge/ai/AiController.java
+++ b/forge-ai/src/main/java/forge/ai/AiController.java
@@ -801,48 +801,62 @@ public class AiController {
         if ("True".equals(card.getSVar("NonStackingEffect")) && isNonDisabledCardInPlay(card.getName())) {
             return AiPlayDecision.NeedsToPlayCriteriaNotMet;
         }
+
         // Trying to play a card that has Buyback without a Buyback cost
-
-        if (card.hasStartOfKeyword("Buyback")) {
-            //if (card.getBuybackAbility()!=null) {
-            if (!sa.isBuyBackAbility()) {
-                boolean wasteBuybackAllowed = false;
-                // About to lose game : allow
-                if (ComputerUtil.aiLifeInDanger(player, true, 0)) {
-                    wasteBuybackAllowed = true;
-                }
-                int copies = CardLists.filter(player.getCardsIn(ZoneType.Hand), CardPredicates.nameEquals(card.getName())).size();
-                // Have two copies : allow
-                if (copies >= 2) {
-                    wasteBuybackAllowed = true;
-                }
-                // Won't be able to afford buyback any time soon
-                // If Buyback cost includes sacrifice, life, discard
-                int neededMana = 0;
-                for (SpellAbility sa2 : GameActionUtil.getOptionalCosts(sa)) {
-                    if (sa2.isOptionalCostPaid(OptionalCost.Buyback)) {
-                        Cost sac = sa2.getPayCosts();
-                        CostAdjustment.adjust(sac, sa2); // Does not recognize Memory Crystal anyway???
-                        neededMana = sac.getCostMana().getMana().getCMC();
-                        if (sac.hasSpecificCostType(CostPayLife.class)
-                                || (sac.hasSpecificCostType(CostDiscard.class)) ||
-                                (sac.hasSpecificCostType(CostSacrifice.class))) {
-                            neededMana = 999;
-                        }
-                    }
-                }
-                int hasMana = ComputerUtilMana.getAvailableManaEstimate(player, false);
-                if (hasMana < neededMana - 1) {
-                    wasteBuybackAllowed = true;
-                }
-
-                if (!wasteBuybackAllowed) return AiPlayDecision.NeedsToPlayCriteriaNotMet;
-            }
+        if (card.hasKeyword(Keyword.BUYBACK) && !sa.isBuyBackAbility() && !canPlaySpellWithoutBuyback(card, sa)) {
+            return AiPlayDecision.NeedsToPlayCriteriaNotMet;
         }
+
         // add any other necessary logic to play a basic spell here
         return ComputerUtilCard.checkNeedsToPlayReqs(card, sa);
     }
 
+    private boolean canPlaySpellWithoutBuyback(Card card, SpellAbility sa) {
+        boolean wasteBuybackAllowed = false;
+
+        // About to lose game : allow
+        if (ComputerUtil.aiLifeInDanger(player, true, 0)) {
+            wasteBuybackAllowed = true;
+        }
+
+        int copies = CardLists.filter(player.getCardsIn(ZoneType.Hand), CardPredicates.nameEquals(card.getName())).size();
+        // Have two copies : allow
+        if (copies >= 2) {
+            wasteBuybackAllowed = true;
+
+        }
+
+        int neededMana = 0;
+        boolean dangerousRecurringCost = false;
+        for (SpellAbility sa2 : GameActionUtil.getOptionalCosts(sa)) {
+            if (sa2.isOptionalCostPaid(OptionalCost.Buyback)) {
+                Cost sac = sa2.getPayCosts();
+                CostAdjustment.adjust(sac, sa2); // TODO: Does not recognize Memory Crystal
+                if (sac.getCostMana() != null) {
+                    neededMana = sac.getCostMana().getMana().getCMC();
+                }
+                if (sac.hasSpecificCostType(CostPayLife.class)
+                        || sac.hasSpecificCostType(CostDiscard.class)
+                        || sac.hasSpecificCostType(CostSacrifice.class)) {
+                    dangerousRecurringCost = true;
+                }
+            }
+        }
+
+        // won't be able to afford buyback any time soon
+        // if Buyback cost includes sacrifice, life, discard
+        if (dangerousRecurringCost) {
+            wasteBuybackAllowed = true;
+        }
+
+        int hasMana = ComputerUtilMana.getAvailableManaEstimate(player, false);
+        if (hasMana < neededMana - 1) {
+            wasteBuybackAllowed = true;
+        }
+
+        return wasteBuybackAllowed;
+    }
+
     // not sure "playing biggest spell" matters?
     private final static Comparator<SpellAbility> saComparator = new Comparator<SpellAbility>() {
         @Override