AI improves:

* AI: fixed that AI was able to targeting an invalid player targets in some use cases (#5630);
* AI: fixed that AI was able to ignore targeted triggers in some use cases;
* AI: improved player targeting for not own chooses (if it's make a choice for another player);

Mage.Client/src/main/java/mage/client/remote/CallbackClientImpl.java

@@ -318,7 +318,6 @@ public class CallbackClientImpl implements CallbackClient {
                         // uses for client side only (example: update after scrollbars support)
                         GamePanel panel = MageFrame.getGame(callback.getObjectId());
                         if (panel != null) {
-                            logger.info("redraw");
                             panel.updateGame();
                         }
                         break;

Mage.Server.Plugins/Mage.Player.AI.MA/src/mage/player/ai/ComputerPlayer6.java

@@ -391,6 +391,7 @@ public class ComputerPlayer6 extends ComputerPlayer /*implements Player*/ {
     protected void resolve(SimulationNode2 node, int depth, Game game) {
         StackObject stackObject = game.getStack().getFirst();
         if (stackObject instanceof StackAbility) {
+            // AI hint for search effects (calc all possible cards for best score)
             SearchEffect effect = getSearchEffect((StackAbility) stackObject);
             if (effect != null
                     && stackObject.getControllerId().equals(playerId)) {

Mage.Server.Plugins/Mage.Player.AI/src/main/java/mage/player/ai/ComputerPlayer.java

@@ -2893,27 +2893,38 @@ public class ComputerPlayer extends PlayerImpl implements Player {
     }
 
     /**
-     * Sets a possible target player
+     * Sets a possible target player. Depends on bad/good outcome
+     *
+     * @param source null on choose and non-null on chooseTarget
      */
     private boolean setTargetPlayer(Outcome outcome, Target target, Ability source, UUID sourceId, UUID abilityControllerId, UUID randomOpponentId, Game game, boolean required) {
+        Outcome affectedOutcome;
+        if (abilityControllerId == this.playerId) {
+            // selects for itself
+            affectedOutcome = outcome;
+        } else {
+            // selects for another player
+            affectedOutcome = Outcome.inverse(outcome);
+        }
+
         if (target.getOriginalTarget() instanceof TargetOpponent) {
             if (source == null) {
                 if (target.canTarget(randomOpponentId, game)) {
                     target.add(randomOpponentId, game);
                     return true;
                 }
-            } else if (target.canTarget(randomOpponentId, source, game)) {
+            } else if (target.canTarget(abilityControllerId, randomOpponentId, source, game)) {
-                target.add(randomOpponentId, game);
+                target.addTarget(randomOpponentId, source, game);
                 return true;
             }
-            for (UUID currentId : game.getOpponents(abilityControllerId)) {
+            for (UUID possibleOpponentId : game.getOpponents(abilityControllerId)) {
                 if (source == null) {
-                    if (target.canTarget(currentId, game)) {
+                    if (target.canTarget(possibleOpponentId, game)) {
-                        target.add(currentId, game);
+                        target.add(possibleOpponentId, game);
                         return true;
                     }
-                } else if (target.canTarget(currentId, source, game)) {
+                } else if (target.canTarget(abilityControllerId, possibleOpponentId, source, game)) {
-                    target.add(currentId, game);
+                    target.addTarget(possibleOpponentId, source, game);
                     return true;
                 }
             }
@@ -2921,8 +2932,9 @@ public class ComputerPlayer extends PlayerImpl implements Player {
         }
 
         if (target.getOriginalTarget() instanceof TargetPlayer) {
-            if (outcome.isGood()) {
+            if (affectedOutcome.isGood()) {
                 if (source == null) {
+                    // good
                     if (target.canTarget(abilityControllerId, game)) {
                         target.add(abilityControllerId, game);
                         return true;
@@ -2934,19 +2946,20 @@ public class ComputerPlayer extends PlayerImpl implements Player {
                         }
                     }
                 } else {
+                    // good
                     if (target.canTarget(abilityControllerId, abilityControllerId, source, game)) {
-                        target.addTarget(playerId, source, game);
+                        target.addTarget(abilityControllerId, source, game);
                         return true;
                     }
                     if (target.isRequired(sourceId, game)) {
-                        if (target.canTarget(randomOpponentId, game)) {
+                        if (target.canTarget(abilityControllerId, randomOpponentId, source, game)) {
-                            target.add(randomOpponentId, game);
+                            target.addTarget(randomOpponentId, source, game);
                             return true;
                         }
                     }
                 }
-
             } else if (source == null) {
+                // bad
                 if (target.canTarget(randomOpponentId, game)) {
                     target.add(randomOpponentId, game);
                     return true;
@@ -2958,13 +2971,14 @@ public class ComputerPlayer extends PlayerImpl implements Player {
                     }
                 }
             } else {
-                if (target.canTarget(randomOpponentId, game)) {
+                // bad
-                    target.add(randomOpponentId, game);
+                if (target.canTarget(abilityControllerId, randomOpponentId, source, game)) {
+                    target.addTarget(randomOpponentId, source, game);
                     return true;
                 }
                 if (required) {
-                    if (target.canTarget(abilityControllerId, game)) {
+                    if (target.canTarget(abilityControllerId, abilityControllerId, source, game)) {
-                        target.add(abilityControllerId, game);
+                        target.addTarget(abilityControllerId, source, game);
                         return true;
                     }
                 }

Mage.Server.Plugins/Mage.Player.AIMinimax/src/mage/player/ai/ComputerPlayer2.java

@@ -351,6 +351,7 @@ public class ComputerPlayer2 extends ComputerPlayer implements Player {
     }
 
     protected int simulatePriority(SimulationNode node, Game game, int alpha, int beta) {
+        // NOT USED in real AI, see ComputerPlayer6
         if (Thread.interrupted()) {
             Thread.currentThread().interrupt();
             logger.debug(indent(node.depth) + "interrupted");

Mage.Tests/src/test/java/org/mage/test/cards/abilities/keywords/HexproofTest.java

@@ -3,6 +3,7 @@ package org.mage.test.cards.abilities.keywords;
 import mage.abilities.keyword.HexproofAbility;
 import mage.constants.PhaseStep;
 import mage.constants.Zone;
+import mage.counters.CounterType;
 import org.junit.Assert;
 import org.junit.Test;
 import org.mage.test.serverside.base.CardTestPlayerBaseWithAIHelps;
@@ -127,6 +128,7 @@ public class HexproofTest extends CardTestPlayerBaseWithAIHelps {
         assertAllCommandsUsed();
 
         assertGraveyardCount(playerA, "Swamp", 1);
+        assertCounterCount(playerA, "Liliana Vess", CounterType.LOYALTY, 5 + 1);
     }
 
     @Test
@@ -158,7 +160,7 @@ public class HexproofTest extends CardTestPlayerBaseWithAIHelps {
     }
 
     @Test
-    public void test_AI_MustTargetOnlyValid() {
+    public void test_AI_MustTargetOnlyValid_1() {
         // +1: Target player discards a card.
         addCard(Zone.BATTLEFIELD, playerA, "Liliana Vess", 1);
         addCard(Zone.HAND, playerA, "Balduvian Bears", 1);
@@ -180,6 +182,54 @@ public class HexproofTest extends CardTestPlayerBaseWithAIHelps {
         // no discarded cards
         assertGraveyardCount(playerA, 0);
         assertGraveyardCount(playerB, 0);
+        // no activated abilities
+        assertCounterCount(playerA, "Liliana Vess", CounterType.LOYALTY, 5 - 2); // search library for -2
+    }
+
+    @Test
+    public void test_AI_MustTargetOnlyValid_2() {
+        // +1: Target player discards a card.
+        addCard(Zone.BATTLEFIELD, playerA, "Liliana Vess", 1);
+        addCard(Zone.HAND, playerA, "Balduvian Bears", 1);
+        addCard(Zone.HAND, playerA, "Swamp", 1);
+        addCard(Zone.HAND, playerB, "Matter Reshaper", 1);
+        addCard(Zone.HAND, playerB, "Mountain", 1);
+        //
+        // You and permanents you control gain hexproof from blue and from black until end of turn.
+        addCard(Zone.HAND, playerB, "Veil of Summer", 1); // instant {G}
+        addCard(Zone.BATTLEFIELD, playerB, "Forest", 1);
+
+        // prepare hexproof
+        castSpell(1, PhaseStep.UPKEEP, playerB, "Veil of Summer");
+
+        // ai must not use +1 on itself (due bad score) and must not use on opponent (due hexproof)
+        aiPlayStep(1, PhaseStep.PRECOMBAT_MAIN, playerA);
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+        assertAllCommandsUsed();
+
+        // no discarded cards
+        assertGraveyardCount(playerA, 0);
+        assertGraveyardCount(playerB, 1); // Veil of Summer
+        // no activated abilities
+        assertCounterCount(playerA, "Liliana Vess", CounterType.LOYALTY, 5 - 2); // search library for -2
+    }
+
+    @Test
+    public void test_AI_Logs() {
+        addCard(Zone.HAND, playerA, "Lightning Bolt", 3);
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 3);
+
+        aiPlayStep(1, PhaseStep.PRECOMBAT_MAIN, playerA);
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+        assertAllCommandsUsed();
+
+        assertLife(playerB, 20 - 3 * 3);
     }
 
     @Test