Turn under control reworked:

 - game: added support for human games (cards like Emrakul, the Promised End, #12878);
 - game: added support of 720.1. to reset control in the turn beginning instead cleanup step (related to #12115);
 - game: added game logs for priorities in cleanup step;
 - game: fixed game freezes and wrong skip settings usages (related to #12878);
 - gui: added playable and choose-able marks for controlling player's cards and permanents, including switched hands;
 - gui: added controlling player name in all choice dialogs;
 - info: control of computer players is it not yet supported;

Author: JayDi85

Mage.Client/src/main/java/mage/client/game/GamePanel.java

@@ -30,8 +30,10 @@
 import mage.game.events.PlayerQueryEvent;
 import mage.players.PlayableObjectStats;
 import mage.players.PlayableObjectsList;
+import mage.util.CardUtil;
 import mage.util.DebugUtil;
 import mage.util.MultiAmountMessage;
+import mage.util.StreamUtils;
 import mage.view.*;
 import org.apache.log4j.Logger;
 import org.mage.plugins.card.utils.impl.ImageManagerImpl;
@@ -53,6 +55,7 @@
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
 
 import static mage.client.dialog.PreferencesDialog.*;
 import static mage.constants.PlayerAction.*;
@@ -1810,6 +1813,7 @@ private void prepareSelectableView() {
 
         // hand
         if (needZone == Zone.HAND || needZone == Zone.ALL) {
+            // my hand
             for (CardView card : lastGameData.game.getMyHand().values()) {
                 if (needSelectable.contains(card.getId())) {
                     card.setChoosable(true);
@@ -1821,6 +1825,34 @@ private void prepareSelectableView() {
                     card.setPlayableStats(needPlayable.getStats(card.getId()));
                 }
             }
+
+            // opponent hands (switching by GUI's button with my hand)
+            List<SimpleCardView> list = lastGameData.game.getOpponentHands().values().stream().flatMap(s -> s.values().stream()).collect(Collectors.toList());
+            for (SimpleCardView card : list) {
+                if (needSelectable.contains(card.getId())) {
+                    card.setChoosable(true);
+                }
+                if (needChosen.contains(card.getId())) {
+                    card.setSelected(true);
+                }
+                if (needPlayable.containsObject(card.getId())) {
+                    card.setPlayableStats(needPlayable.getStats(card.getId()));
+                }
+            }
+
+            // watched hands (switching by GUI's button with my hand)
+            list = lastGameData.game.getWatchedHands().values().stream().flatMap(s -> s.values().stream()).collect(Collectors.toList());
+            for (SimpleCardView card : list) {
+                if (needSelectable.contains(card.getId())) {
+                    card.setChoosable(true);
+                }
+                if (needChosen.contains(card.getId())) {
+                    card.setSelected(true);
+                }
+                if (needPlayable.containsObject(card.getId())) {
+                    card.setPlayableStats(needPlayable.getStats(card.getId()));
+                }
+            }
         }
 
         // stack

Mage.Server.Plugins/Mage.Player.Human/src/mage/player/human/HumanPlayer.java

@@ -37,6 +37,7 @@
 import mage.players.Player;
 import mage.players.PlayerImpl;
 import mage.players.PlayerList;
+import mage.players.net.UserData;
 import mage.target.Target;
 import mage.target.TargetAmount;
 import mage.target.TargetCard;
@@ -93,7 +94,7 @@ public class HumanPlayer extends PlayerImpl {
     // * - GAME thread: open response for income command and wait (go to sleep by response.wait)
     // * - CALL thread: on closed response - waiting open status of player's response object (if it's too long then cancel the answer)
     // * - CALL thread: on opened response - save answer to player's response object and notify GAME thread about it by response.notifyAll
-    // * - GAME thread: on nofify from response - check new answer value and process it (if it bad then repeat and wait the next one);
+    // * - GAME thread: on notify from response - check new answer value and process it (if it bad then repeat and wait the next one);
     private transient Boolean responseOpenedForAnswer = false; // GAME thread waiting new answer
     private transient long responseLastWaitingThreadId = 0;
     private final transient PlayerResponse response = new PlayerResponse();
@@ -1159,25 +1160,27 @@ public boolean priority(Game game) {
         // TODO: change pass and other states like passedUntilStackResolved for controlling player, not for "this"
         // TODO: check and change all "this" to controling player calls, many bugs with hand, mana, skips - https://github.com/magefree/mage/issues/2088
         // TODO: use controlling player in all choose dialogs (and canRespond too, what's with take control of player AI?!)
+        UserData controllingUserData = this.userData;
         if (canRespond()) {
-            HumanPlayer controllingPlayer = this;
-            if (isGameUnderControl()) { // TODO: must be ! to get real controlling player
+            if (!isGameUnderControl()) {
                 Player player = game.getPlayer(getTurnControlledBy());
                 if (player instanceof HumanPlayer) {
-                    controllingPlayer = (HumanPlayer) player;
+                    controllingUserData = player.getUserData();
+                } else {
+                    // TODO: add computer opponent here?!
                 }
             }
 
             // TODO: check that all skips and stops used from real controlling player
             //  like holdingPriority (is it a bug here?)
             if (getJustActivatedType() != null && !holdingPriority) {
-                if (controllingPlayer.getUserData().isPassPriorityCast()
+                if (controllingUserData.isPassPriorityCast()
                         && getJustActivatedType() == AbilityType.SPELL) {
                     setJustActivatedType(null);
                     pass(game);
                     return false;
                 }
-                if (controllingPlayer.getUserData().isPassPriorityActivation()
+                if (controllingUserData.isPassPriorityActivation()
                         && getJustActivatedType().isNonManaActivatedAbility()) {
                     setJustActivatedType(null);
                     pass(game);
@@ -1252,7 +1255,7 @@ && getJustActivatedType().isNonManaActivatedAbility()) {
                             // it's main step
                             if (!skippedAtLeastOnce
                                     || (!playerId.equals(game.getActivePlayerId())
-                                    && !controllingPlayer.getUserData().getUserSkipPrioritySteps().isStopOnAllMainPhases())) {
+                                    && !controllingUserData.getUserSkipPrioritySteps().isStopOnAllMainPhases())) {
                                 skippedAtLeastOnce = true;
                                 if (passWithManaPoolCheck(game)) {
                                     return false;
@@ -1274,8 +1277,7 @@ && getJustActivatedType().isNonManaActivatedAbility()) {
                             // it's end of turn step
                             if (!skippedAtLeastOnce
                                     || (playerId.equals(game.getActivePlayerId())
-                                    && !controllingPlayer
-                                    .getUserData()
+                                    && !controllingUserData
                                     .getUserSkipPrioritySteps()
                                     .isStopOnAllEndPhases())) {
                                 skippedAtLeastOnce = true;
@@ -1295,7 +1297,7 @@ && getJustActivatedType().isNonManaActivatedAbility()) {
                     }
 
                     if (!dontCheckPassStep
-                            && checkPassStep(game, controllingPlayer)) {
+                            && checkPassStep(game, controllingUserData)) {
                         if (passWithManaPoolCheck(game)) {
                             return false;
                         }
@@ -1308,8 +1310,7 @@ && checkPassStep(game, controllingPlayer)) {
                     if (passedUntilStackResolved) {
                         if (haveNewObjectsOnStack
                                 && (playerId.equals(game.getActivePlayerId())
-                                && controllingPlayer
-                                .getUserData()
+                                && controllingUserData
                                 .getUserSkipPrioritySteps()
                                 .isStopOnStackNewObjects())) {
                             // new objects on stack -- disable "pass until stack resolved"
@@ -1433,17 +1434,17 @@ private UUID getFixedResponseUUID(Game game) {
         return response.getUUID();
     }
 
-    private boolean checkPassStep(Game game, HumanPlayer controllingPlayer) {
+    private boolean checkPassStep(Game game, UserData controllingUserData) {
         try {
 
             if (playerId.equals(game.getActivePlayerId())) {
-                return !controllingPlayer.getUserData().getUserSkipPrioritySteps().getYourTurn().isPhaseStepSet(game.getTurnStepType());
+                return !controllingUserData.getUserSkipPrioritySteps().getYourTurn().isPhaseStepSet(game.getTurnStepType());
             } else {
-                return !controllingPlayer.getUserData().getUserSkipPrioritySteps().getOpponentTurn().isPhaseStepSet(game.getTurnStepType());
+                return !controllingUserData.getUserSkipPrioritySteps().getOpponentTurn().isPhaseStepSet(game.getTurnStepType());
             }
         } catch (NullPointerException ex) {
-            if (controllingPlayer.getUserData() != null) {
-                if (controllingPlayer.getUserData().getUserSkipPrioritySteps() != null) {
+            if (controllingUserData != null) {
+                if (controllingUserData.getUserSkipPrioritySteps() != null) {
                     if (game.getStep() != null) {
                         if (game.getTurnStepType() == null) {
                             logger.error("game.getTurnStepType() == null");
@@ -2929,19 +2930,8 @@ private void setTriggerAutoOrder(PlayerAction playerAction, Game game, Object da
     protected boolean passWithManaPoolCheck(Game game) {
         if (userData.confirmEmptyManaPool()
                 && game.getStack().isEmpty() && getManaPool().count() > 0 && getManaPool().canLostManaOnEmpty()) {
-            String activePlayerText;
-            if (game.isActivePlayer(playerId)) {
-                activePlayerText = "Your turn";
-            } else {
-                activePlayerText = game.getPlayer(game.getActivePlayerId()).getName() + "'s turn";
-            }
-            String priorityPlayerText = "";
-            if (!isGameUnderControl()) {
-                priorityPlayerText = " / priority " + game.getPlayer(game.getPriorityPlayerId()).getName();
-            }
-            // TODO: chooseUse and other dialogs must be under controlling player
-            if (!chooseUse(Outcome.Detriment, GameLog.getPlayerConfirmColoredText("You still have mana in your mana pool and it will be lose. Pass anyway?")
-                    + GameLog.getSmallSecondLineText(activePlayerText + " / " + game.getTurnStepType().toString() + priorityPlayerText), null, game)) {
+            String message = GameLog.getPlayerConfirmColoredText("You still have mana in your mana pool and it will be lose. Pass anyway?");
+            if (!chooseUse(Outcome.Detriment, message, null, game)) {
                 sendPlayerAction(PlayerAction.PASS_PRIORITY_CANCEL_ALL_ACTIONS, game, null);
                 return false;
             }

Mage.Server/src/main/java/mage/server/game/GameController.java

@@ -906,14 +906,14 @@ private synchronized void multiAmount(UUID playerId, final List<MultiAmountMessa
         perform(playerId, playerId1 -> getGameSession(playerId1).getMultiAmount(messages, min, max, options));
     }
 
-    private void informOthers(UUID playerId) {
+    private void informOthers(UUID waitingPlayerId) {
         StringBuilder message = new StringBuilder();
         if (game.getStep() != null) {
             message.append(game.getTurnStepType().toString()).append(" - ");
         }
-        message.append("Waiting for ").append(game.getPlayer(playerId).getLogName());
+        message.append("Waiting for ").append(game.getPlayer(waitingPlayerId).getLogName());
         for (final Entry<UUID, GameSessionPlayer> entry : getGameSessionsMap().entrySet()) {
-            if (!entry.getKey().equals(playerId)) {
+            if (!entry.getKey().equals(waitingPlayerId)) {
                 entry.getValue().inform(message.toString());
             }
         }
@@ -1030,7 +1030,7 @@ private void perform(UUID playerId, Command command, boolean informOthers) {
         // TODO: if watcher disconnects then game freezes with active timer, must be fix for such use case
         //  same for another player (can be fixed by super-duper connection)
         if (informOthers) {
-            informOthers(playerId);
+            informOthers(realPlayerController.getId());
         }
     }
 

Mage.Server/src/main/java/mage/server/game/GameSessionPlayer.java

@@ -212,13 +212,14 @@ public static GameView prepareGameView(Game game, UUID playerId, UUID userId) {
         // game view calculation can take some time and can be called from non-game thread,
         // so use copy for thread save (protection from ConcurrentModificationException)
         Game sourceGame = game.copy();
+        GameView gameView = new GameView(sourceGame.getState(), sourceGame, playerId, null);
 
+        // playable info (if opponent under control then show opponent's playable)
         Player player = sourceGame.getPlayer(playerId); // null for watcher
-        GameView gameView = new GameView(sourceGame.getState(), sourceGame, playerId, null);
-        if (player != null) {
-            if (gameView.getPriorityPlayerName().equals(player.getName())) {
-                gameView.setCanPlayObjects(player.getPlayableObjects(sourceGame, Zone.ALL));
-            }
+        Player priorityPlayer = sourceGame.getPlayer(sourceGame.getPriorityPlayerId());
+        Player controllingPlayer = priorityPlayer == null ? null : sourceGame.getPlayer(priorityPlayer.getTurnControlledBy());
+        if (controllingPlayer != null && player == controllingPlayer) {
+            gameView.setCanPlayObjects(priorityPlayer.getPlayableObjects(sourceGame, Zone.ALL));
         }
 
         processControlledPlayers(sourceGame, player, gameView);

Mage.Tests/src/test/java/org/mage/test/load/LoadCallbackClient.java

@@ -104,18 +104,17 @@ public void onCallback(ClientCallback callback) {
                 GameClientMessage message = (GameClientMessage) callback.getData();
                 this.gameView = message.getGameView();
                 log.info(getLogStartInfo() + " target: " + message.getMessage());
-                switch (message.getMessage()) {
-                    case "Select a starting player":
-                        session.sendPlayerUUID(gameId, playerId);
-                        return;
-                    case "Select a card to discard":
-                        log.info(getLogStartInfo() + "hand size: " + gameView.getMyHand().size());
-                        SimpleCardView card = gameView.getMyHand().values().iterator().next();
-                        session.sendPlayerUUID(gameId, card.getId());
-                        return;
-                    default:
-                        log.error(getLogStartInfo() + "unknown GAME_TARGET message: " + message.toString());
-                        return;
+                if (message.getMessage().startsWith("Select a starting player")) {
+                    session.sendPlayerUUID(gameId, playerId);
+                    return;
+                } else if (message.getMessage().startsWith("Select a card to discard")) {
+                    log.info(getLogStartInfo() + "hand size: " + gameView.getMyHand().size());
+                    SimpleCardView card = gameView.getMyHand().values().iterator().next();
+                    session.sendPlayerUUID(gameId, card.getId());
+                    return;
+                } else {
+                    log.error(getLogStartInfo() + "unknown GAME_TARGET message: " + message.toString());
+                    return;
                 }
             }
 

Mage/src/main/java/mage/abilities/common/delayed/AtTheEndOfTurnStepPostDelayedTriggeredAbility.java

@@ -550,6 +550,12 @@ default boolean isOpponent(Player player, UUID playerToCheckId) {
     @Deprecated // TODO: must research usage and remove it from all non engine code (example: Bestow ability, ProcessActions must be used instead)
     boolean checkStateAndTriggered();
 
+    /**
+     * Play priority by all players
+     *
+     * @param activePlayerId starting priority player
+     * @param resuming false to reset passed priority and ask it again
+     */
     void playPriority(UUID activePlayerId, boolean resuming);
 
     void resetControlAfterSpellResolve(UUID topId);