From 6d599d2b8c64cd8e71802c53f732ec4a311fbdb8 Mon Sep 17 00:00:00 2001
From: Agetian <stavdev@mail.ru>
Date: Thu, 13 Sep 2018 11:27:56 +0300
Subject: [PATCH] - Basic SurveilAi logic, largely inspired with the ScryAi
 logic.

---
 .../main/java/forge/ai/ability/SurveilAi.java | 72 +++++++++++++++++--
 1 file changed, 66 insertions(+), 6 deletions(-)

diff --git a/forge-ai/src/main/java/forge/ai/ability/SurveilAi.java b/forge-ai/src/main/java/forge/ai/ability/SurveilAi.java
index 47c64349396..fe7b1671e67 100644
--- a/forge-ai/src/main/java/forge/ai/ability/SurveilAi.java
+++ b/forge-ai/src/main/java/forge/ai/ability/SurveilAi.java
@@ -1,9 +1,13 @@
 package forge.ai.ability;
 
 import forge.ai.SpellAbilityAi;
+import forge.game.phase.PhaseHandler;
+import forge.game.phase.PhaseType;
 import forge.game.player.Player;
 import forge.game.player.PlayerActionConfirmMode;
 import forge.game.spellability.SpellAbility;
+import forge.game.zone.ZoneType;
+import forge.util.MyRandom;
 
 public class SurveilAi extends SpellAbilityAi {
 
@@ -14,10 +18,8 @@ public class SurveilAi extends SpellAbilityAi {
     @Override
     protected boolean doTriggerAINoCost(Player ai, SpellAbility sa, boolean mandatory) {
 
-        if (sa.usesTargeting()) { // It doesn't appear that Scry ever targets
-            // ability is targeted
+        if (sa.usesTargeting()) { // TODO: It doesn't appear that Surveil ever targets, is this necessary?
             sa.resetTargets();
-
             sa.getTargets().add(ai);
         }
 
@@ -33,10 +35,68 @@ public class SurveilAi extends SpellAbilityAi {
         return doTriggerAINoCost(ai, sa, false);
     }
 
-    /*
-     * (non-Javadoc)
-     * @see forge.ai.SpellAbilityAi#confirmAction(forge.game.player.Player, forge.game.spellability.SpellAbility, forge.game.player.PlayerActionConfirmMode, java.lang.String)
+    /**
+     * Checks if the AI will play a SpellAbility based on its phase restrictions
      */
+    @Override
+    protected boolean checkPhaseRestrictions(final Player ai, final SpellAbility sa, final PhaseHandler ph) {
+        // if the Surveil ability requires tapping and has a mana cost, it's best done at the end of opponent's turn
+        // and right before the beginning of AI's turn, if possible, to avoid mana locking the AI and also to
+        // try to scry right before drawing a card. Also, avoid tapping creatures in the AI's turn, if possible,
+        // even if there's no mana cost.
+        if (sa.getPayCosts() != null) {
+            if (sa.getPayCosts().hasTapCost()
+                    && (sa.getPayCosts().hasManaCost() || (sa.getHostCard() != null && sa.getHostCard().isCreature()))
+                    && !SpellAbilityAi.isSorcerySpeed(sa)) {
+                return ph.getNextTurn() == ai && ph.is(PhaseType.END_OF_TURN);
+            }
+        }
+
+        // in the player's turn Surveil should only be done in Main1 or in Upkeep if able
+        if (ph.isPlayerTurn(ai)) {
+            if (SpellAbilityAi.isSorcerySpeed(sa)) {
+                return ph.is(PhaseType.MAIN1) || sa.hasParam("Planeswalker");
+            } else {
+                return ph.is(PhaseType.UPKEEP);
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Checks if the AI will play a SpellAbility with the specified AiLogic
+     */
+    @Override
+    protected boolean checkAiLogic(final Player ai, final SpellAbility sa, final String aiLogic) {
+        if ("Never".equals(aiLogic)) {
+            return false;
+        }
+
+        // TODO: add card-specific Surveil AI logic here when/if necessary
+
+        return true;
+    }
+
+    @Override
+    protected boolean checkApiLogic(Player ai, SpellAbility sa) {
+        // Makes no sense to do Surveil when there's nothing in the library
+        if (ai.getCardsIn(ZoneType.Library).isEmpty()) {
+            return false;
+        }
+
+        double chance = .4; // 40 percent chance for instant speed
+        if (SpellAbilityAi.isSorcerySpeed(sa)) {
+            chance = .667; // 66.7% chance for sorcery speed (since it will never activate EOT)
+        }
+
+        boolean randomReturn = MyRandom.getRandom().nextFloat() <= Math.pow(chance, sa.getActivationsThisTurn() + 1);
+        if (SpellAbilityAi.playReusable(ai, sa)) {
+            randomReturn = true;
+        }
+
+        return randomReturn;
+    }
+
     @Override
     public boolean confirmAction(Player player, SpellAbility sa, PlayerActionConfirmMode mode, String message) {
         return true;