From db1839c4029a8c7ce4fe6a01d408cbd69173a394 Mon Sep 17 00:00:00 2001
From: Agetian <stavdev@mail.ru>
Date: Mon, 2 Oct 2017 04:50:46 +0000
Subject: [PATCH] - A less invasive Thought Lash hack for the AI.

---
 .../java/forge/ai/PlayerControllerAi.java     |  4 +--
 .../java/forge/game/cost/CostPayment.java     | 29 ++-----------------
 2 files changed, 5 insertions(+), 28 deletions(-)

diff --git a/forge-ai/src/main/java/forge/ai/PlayerControllerAi.java b/forge-ai/src/main/java/forge/ai/PlayerControllerAi.java
index a422c1f19d8..828dc36a4b5 100644
--- a/forge-ai/src/main/java/forge/ai/PlayerControllerAi.java
+++ b/forge-ai/src/main/java/forge/ai/PlayerControllerAi.java
@@ -465,8 +465,8 @@ public class PlayerControllerAi extends PlayerController {
         ability.setActivatingPlayer(c.getController());
 
         // FIXME: This is a hack to check if the AI can play the "exile from library" pay costs (Cumulative Upkeep,
-        // e.g. Thought Lash). We have to do it early since the cost will later be reconsolidated into a single
-        // payment for the AI, to avoid cheating (otherwise the AI repeatedly "exiles" the same card multiple times)
+        // e.g. Thought Lash). We have to do it and bail early if the AI can't pay, because otherwise the AI will
+        // pay the cost partially, which should not be possible
         int nExileLib = 0;
         List<CostPart> parts = CostAdjustment.adjust(cost, sa).getCostParts();
         for (final CostPart part : parts) {
diff --git a/forge-game/src/main/java/forge/game/cost/CostPayment.java b/forge-game/src/main/java/forge/game/cost/CostPayment.java
index 6f66362dbba..9785a12a49b 100644
--- a/forge-game/src/main/java/forge/game/cost/CostPayment.java
+++ b/forge-game/src/main/java/forge/game/cost/CostPayment.java
@@ -170,38 +170,15 @@ public class CostPayment {
 
         final Game game = decisionMaker.getPlayer().getGame();
 
-        // FIXME: This is a hack which is necessary to make the AI pay the Cumulative Upkeep with "Exile a card from
-        // the top of your library" (Thought Lash) without cheating. Otherwise the AI pays only one card, no matter
-        // the age counters. We need a better solution here.
-        int nExileLib = 0;
-        List<CostPart> partsToChange = Lists.newArrayList();
-        CostExile primeExile = null;
-        for (final CostPart part : parts) {
-            if (part instanceof CostExile) {
-                CostExile exile = (CostExile) part;
-                if (exile.from == ZoneType.Library) {
-                    nExileLib += exile.convertAmount();
-                    if (nExileLib == 1) {
-                        primeExile = exile;
-                    } else {
-                        partsToChange.add(exile);
-                    }
-                }
-            }
-        }
-        if (nExileLib > 1 && primeExile != null) {
-            parts.removeAll(partsToChange);
-            primeExile.setAmount(String.valueOf(nExileLib));
-        }
-        // - End of hack for Cumulative Upkeep: Exile a card from the top of your library -
-
         for (final CostPart part : parts) {
             PaymentDecision decision = part.accept(decisionMaker);
+            // the AI will try to exile the same card repeatedly unless it does it immediately
+            final boolean payImmediately = part instanceof CostExile && ((CostExile) part).from == ZoneType.Library;
             if (null == decision) return false;
 
             // wrap the payment and push onto the cost stack
             game.costPaymentStack.push(part, this);
-            if (decisionMaker.paysRightAfterDecision() && !part.payAsDecided(decisionMaker.getPlayer(), decision, ability)) {
+            if ((decisionMaker.paysRightAfterDecision() || payImmediately) && !part.payAsDecided(decisionMaker.getPlayer(), decision, ability)) {
                 game.costPaymentStack.pop(); // cost is resolved
                 return false;
             }