WIP - observability check rewrite.

omicron-api/src/main/java/com/lyndir/omicron/api/model/GameObservable.java

@@ -0,0 +1,21 @@
+package com.lyndir.omicron.api.model;
+
+import com.lyndir.omicron.api.util.Maybe;
+
+
+/**
+ * @author lhunath, 2/25/2014
+ */
+public interface GameObservable {
+
+    /**
+     * @return The player that has control over this observable, if any.
+     */
+    Maybe<? extends IPlayer> checkOwner();
+
+    /**
+     * @return The observable's location or {@link Maybe#unknown()} if the current player doesn't own the observable and none of its game objects can observe it.
+     */
+    Maybe<? extends ITile> checkLocation()
+            throws Security.NotAuthenticatedException;
+}

omicron-api/src/main/java/com/lyndir/omicron/api/model/GameObserver.java

@@ -15,14 +15,14 @@
 public interface GameObserver {
 
     /**
-     * Check whether the current object can observe the tile at the given location.
+     * Check whether the current object can observe given observable.
      *
-     * @param location The tile that this observer is trying to see.
+     * @param observable The observable that this observer is trying to see.
      *
-     * @return true if the current player is allowed to know and the given tile is visible to this observer.
+     * @return true if the current player is able and allowed to observe the target.
      */
     @Authenticated
-    Maybool canObserve(@Nonnull ITile location)
+    Maybool canObserve(@Nonnull GameObservable observable)
             throws Security.NotAuthenticatedException;
 
     /**
@@ -34,11 +34,4 @@ Maybool canObserve(@Nonnull ITile location)
     @Authenticated
     Iterable<? extends ITile> listObservableTiles()
             throws Security.NotAuthenticatedException, Security.NotObservableException;
-
-    /**
-     * @return The player that has control over this observer, if any.
-     */
-    @Nonnull
-    // TODO: This should return a Maybe to avoid being able to detect ownership changes on objects that are not observable.
-    Optional<? extends IPlayer> getOwner();
 }

omicron-api/src/main/java/com/lyndir/omicron/api/model/IGameObject.java

@@ -5,7 +5,6 @@
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableCollection;
 import com.lyndir.lhunath.opal.system.util.PredicateNN;
-import com.lyndir.omicron.api.util.Maybe;
 import java.util.List;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -16,7 +15,7 @@
  *
  * @author lhunath
  */
-public interface IGameObject extends GameObserver {
+public interface IGameObject extends GameObserver, GameObservable {
 
     @Nonnull
     IGameObjectController<? extends IGameObject> getController();
@@ -28,9 +27,6 @@ boolean isOwnedByCurrentPlayer()
 
     IGame getGame();
 
-    Maybe<? extends ITile> checkLocation()
-            throws NotAuthenticatedException;
-
     IUnitType getType();
 
     /**

omicron-api/src/main/java/com/lyndir/omicron/api/model/IPlayer.java

@@ -14,10 +14,6 @@ public interface IPlayer extends GameObserver {
     @Nonnull
     IPlayerController getController();
 
-    @Override
-    Maybool canObserve(@Nonnull ITile location)
-            throws Security.NotAuthenticatedException;
-
     int getPlayerID();
 
     boolean hasKey(PlayerKey playerKey);

omicron-api/src/main/java/com/lyndir/omicron/api/model/IPlayerController.java

@@ -19,7 +19,7 @@ public interface IPlayerController extends GameObserver {
      *
      * @return A list of game objects owned by this controller's player.
      */
-    ImmutableCollection<? extends IGameObject> listObjects()
+    ImmutableSet<? extends IGameObject> listObjects()
             throws NotAuthenticatedException;
 
     /**

omicron-api/src/main/java/com/lyndir/omicron/api/model/PublicGameObject.java

@@ -51,8 +51,8 @@ public IGameObjectController<? extends IGameObject> getController() {
 
     @Nonnull
     @Override
-    public Optional<? extends IPlayer> getOwner() {
-        return core.getOwner();
+    public Optional<? extends IPlayer> checkOwner() {
+        return core.checkOwner();
     }
 
     @Override

omicron-api/src/main/java/com/lyndir/omicron/api/model/Security.java

@@ -16,8 +16,10 @@
 
 package com.lyndir.omicron.api.model;
 
+import static com.google.common.base.Preconditions.checkArgument;
 import static com.lyndir.omicron.api.model.error.ExceptionUtils.*;
 
+import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.lyndir.lhunath.opal.system.util.Job;
 import com.lyndir.lhunath.opal.system.util.ObjectUtils;
@@ -76,13 +78,13 @@ static void playerRun(final IPlayer jobPlayer, final Runnable job) {
     }
 
     public static void authenticate(final IPlayer currentPlayer, final PlayerKey playerKey) {
-        Preconditions.checkArgument( currentPlayer.hasKey( playerKey ), "Cannot authenticate, key does not match player: ", currentPlayer );
+        checkArgument( currentPlayer.hasKey( playerKey ), "Cannot authenticate, key does not match player: ", currentPlayer );
 
         currentPlayerTL.set( currentPlayer );
     }
 
     public static void authenticatedRun(final IPlayer currentPlayer, final PlayerKey playerKey, final Runnable job) {
-        Preconditions.checkArgument( currentPlayer.hasKey( playerKey ), "Cannot authenticate, key does not match player: ", currentPlayer );
+        checkArgument( currentPlayer.hasKey( playerKey ), "Cannot authenticate, key does not match player: ", currentPlayer );
 
         playerRun( currentPlayer, job );
     }
@@ -95,6 +97,15 @@ static boolean isGod() {
         return !godTL.get().isEmpty() && godTL.get().peek();
     }
 
+    /**
+     * @return true if the current player is god or can observe the target.
+     *
+     * @see IPlayer#canObserve(GameObservable)
+     */
+    static boolean currentPlayerCanObserve(final GameObservable gameObservable) {
+        return isGod() || currentPlayer().canObserve( gameObservable ).isTrue();
+    }
+
     @Nonnull
     static IPlayer currentPlayer()
             throws NotAuthenticatedException {
@@ -109,31 +120,23 @@ static IPlayer currentPlayer()
         return currentPlayer;
     }
 
-    public static void assertOwned(final GameObserver observer)
+    public static void assertOwned(final GameObservable observable)
             throws NotAuthenticatedException, NotOwnedException {
         if (isGod())
             return;
 
-        assertSecure( observer.getOwner().isPresent() && ObjectUtils.equals( observer.getOwner().get(), currentPlayer() ), //
-                      NotOwnedException.class, observer );
-    }
-
-    public static void assertObservable(final ITile location)
-            throws NotAuthenticatedException, NotObservableException {
-        if (isGod())
-            return;
-
-        assertSecure( currentPlayer().canObserve( location ).isTrue(), //
-                      NotObservableException.class, location );
+        Maybe<? extends IPlayer> owner = observable.checkOwner();
+        assertSecure( owner.presence() == Maybe.Presence.PRESENT && ObjectUtils.equals( owner.get(), currentPlayer() ), //
+                      NotOwnedException.class, observable );
     }
 
-    public static void assertObservable(final IGameObject gameObject)
+    public static void assertObservable(final GameObservable observable)
             throws NotAuthenticatedException, NotObservableException {
         if (isGod())
             return;
 
-        assertSecure( gameObject.checkLocation().presence() == Maybe.Presence.PRESENT, //
-                      NotObservableException.class, gameObject );
+        assertSecure( currentPlayer().canObserve( observable ).isTrue(), //
+                      NotObservableException.class, observable );
     }
 
     public static class NotAuthenticatedException extends OmicronSecurityException {

omicron-api/src/main/java/com/lyndir/omicron/api/util/Maybe.java

@@ -36,14 +36,23 @@ public static <T> Maybe<T> unknown() {
         return new Unknown<>();
     }
 
+    /**
+     * @return {@link Presence#ABSENT} if reference is null, otherwise {@link Presence#PRESENT}.
+     */
     public static <T> Maybe<T> fromNullable(@Nullable final T reference) {
         return reference == null? Maybe.<T>absent(): new Present<>( reference );
     }
 
+    /**
+     * @return {@link Presence#ABSENT} if reference is {@link Optional#absent()}, otherwise {@link Presence#PRESENT}.
+     */
     public static <T> Maybe<T> fromOptional(final Optional<T> reference) {
         return reference.isPresent()? new Present<>( reference.get() ): Maybe.<T>absent();
     }
 
+    /**
+     * @return Always {@link Presence#PRESENT}.
+     */
     public static <T> Maybe<T> of(@Nonnull final T reference) {
         return new Present<>( reference );
     }

omicron-api/src/main/java/com/lyndir/omicron/api/util/Maybool.java

@@ -1,5 +1,8 @@
 package com.lyndir.omicron.api.util;
 
+import javax.annotation.Nullable;
+
+
 /**
  * @author lhunath, 2013-08-17
  */
@@ -40,4 +43,18 @@ public boolean isKnown() {
     public abstract boolean isTrue();
 
     public abstract boolean isKnown();
+
+    /**
+     * @return YES if value is true, NO if value is false.
+     */
+    public static Maybool from(final boolean value) {
+        return value? YES: NO;
+    }
+
+    /**
+     * @return UNKNOWN if value is null, YES if value is true, NO if value is false.
+     */
+    public static Maybool fromNullable(@Nullable final Boolean value) {
+        return value == null? UNKNOWN : value? YES: NO;
+    }
 }

omicron-cli/src/main/java/com/lyndir/omicron/cli/command/ListCommand.java

@@ -1,7 +1,5 @@
 package com.lyndir.omicron.cli.command;
 
-import static com.lyndir.lhunath.opal.system.util.ObjectUtils.*;
-
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
 import com.lyndir.omicron.api.model.*;
@@ -70,7 +68,7 @@ public void objects(final Iterator<String> tokens) {
         for (final IGameObject gameObject : gameObjectBuilder.build()) {
             ITile location = gameObject.checkLocation().get();
             inf( "%5s | %20s | (%7s: %3d, %3d) | %s", //
-                 gameObject.getObjectID(), ifNotNullElse( IPlayer.class, gameObject.getOwner().orNull(), "-" ).getName(),
+                 gameObject.getObjectID(), ifNotNullElse( IPlayer.class, gameObject.checkOwner().orNull(), "-" ).getName(),
                  location.getLevel().getType().getName(), location.getPosition().getX(), location.getPosition().getY(),
                  gameObject.getType().getTypeName() );
         }