BauSystem_Main/src/de/steamwar/bausystem/features/tracer/Trace.java

@@ -34,6 +34,7 @@ import java.util.function.Function;
 import java.util.stream.Collectors;
 
 public class Trace { // TODO: Add UUID for file saving and so on!
+
     /**
      * Region this trace has been recorded in
      */
@@ -225,25 +226,6 @@ public class Trace { // TODO: Add UUID for file saving and so on!
         return bundles;
     }
 
-    /**
-     * Makes the first passed player follow the trace render of the second passed player
-     *
-     * @param player
-     * @param toFollow
-     */
-    public void follow(Player player, Player toFollow) {
-        throw new UnsupportedOperationException();
-    }
-
-    /**
-     * Makes the passed player stop following any other players trace render
-     *
-     * @param player
-     */
-    public void unfollow(Player player) {
-        throw new UnsupportedOperationException();
-    }
-
     /**
      * Hides this trail for the given player
      *
@@ -252,8 +234,7 @@ public class Trace { // TODO: Add UUID for file saving and so on!
     public void hide(Player player) {
         REntityServer entityServer = entityServerMap.remove(player);
         if (entityServer == null) return;
-        entityServer.removePlayer(player);
-        if (entityServer.getPlayers().isEmpty()) entityServer.close();
+        entityServer.close();
     }
 
     @Override

BauSystem_Main/src/de/steamwar/bausystem/features/tracer/TraceCommand.java

@@ -155,18 +155,18 @@ public class TraceCommand extends SWCommand {
 
     @Register(value = "follow", description = "TRACE_COMMAND_HELP_SHOW")
     public void follow(@Validator Player player, Player toFollow) {
-        // TODO: Implement
-        for (Trace trace : manager.getAll()) {
-            trace.follow(player, toFollow);
+        if (player == toFollow) {
+            // TODO: Implement message
+            return;
         }
+        manager.follow(player, toFollow);
+        // TODO: Implement message
     }
 
     @Register(value = "unfollow", description = "TRACE_COMMAND_HELP_SHOW")
     public void unfollow(@Validator Player player) {
-        // TODO: Implement
-        for (Trace trace : manager.getAll()) {
-            trace.unfollow(player);
-        }
+        manager.unfollow(player);
+        // TODO: Implement message
     }
 
     @ClassMapper(value = Trace.class, local = true)

BauSystem_Main/src/de/steamwar/bausystem/features/tracer/TraceManager.java

@@ -40,6 +40,8 @@ public class TraceManager implements Listener {
 
     private final Map<Region, Map<Player, PlayerTraceShowData>> showDataPerRegionPerPlayer = new HashMap<>();
 
+    private final Map<Player, Set<Player>> followerMap = new HashMap<>();
+
     /**
      * Utility variable to keep track of the next open trace id;
      */
@@ -54,6 +56,9 @@ public class TraceManager implements Listener {
     protected int add(Trace trace) {
         showDataPerRegionPerPlayer.getOrDefault(trace.getRegion(), Collections.emptyMap()).forEach((player, playerTraceShowData) -> {
             trace.render(player, playerTraceShowData);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(follower -> {
+                trace.render(follower, playerTraceShowData);
+            });
         });
         traces.put(nextOpenId, trace);
         tracesByRegion.computeIfAbsent(trace.getRegion(), region -> new HashMap<>()).put(nextOpenId, trace);
@@ -63,7 +68,16 @@ public class TraceManager implements Listener {
 
     protected void addAll(Trace trace, List<TNTPoint> TNTPoints) {
         trace.addAll(TNTPoints, player -> {
-            return showDataPerRegionPerPlayer.getOrDefault(trace.getRegion(), Collections.emptyMap()).get(player);
+            Map.Entry<Player, Set<Player>> entry = followerMap.entrySet()
+                    .stream()
+                    .filter(playerSetEntry -> playerSetEntry.getValue().contains(player))
+                    .findFirst()
+                    .orElse(null);
+            if (entry == null) {
+                return showDataPerRegionPerPlayer.getOrDefault(trace.getRegion(), Collections.emptyMap()).get(player);
+            } else {
+                return showDataPerRegionPerPlayer.getOrDefault(trace.getRegion(), Collections.emptyMap()).get(entry.getKey());
+            }
         });
     }
 
@@ -78,6 +92,7 @@ public class TraceManager implements Listener {
         Trace trace = traces.remove(id);
         showDataPerRegionPerPlayer.get(trace.getRegion()).forEach((player, playerTraceShowData) -> {
             trace.hide(player);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(trace::hide);
         });
         tracesByRegion.get(trace.getRegion()).remove(id);
         return true;
@@ -92,8 +107,10 @@ public class TraceManager implements Listener {
                 .flatMap(map -> map.entrySet().stream())
                 .map(Map.Entry::getKey)
                 .forEach(player -> {
+                    Set<Player> players = followerMap.getOrDefault(player, Collections.emptySet());
                     traces.values().forEach(trace -> {
                         trace.hide(player);
+                        players.forEach(trace::hide);
                     });
                 });
         traces.clear();
@@ -144,10 +161,15 @@ public class TraceManager implements Listener {
      * @param playerTraceShowData
      */
     public void show(Player player, PlayerTraceShowData playerTraceShowData) {
+        unfollow(player);
+
         Region region = Region.getRegion(player.getLocation());
         showDataPerRegionPerPlayer.computeIfAbsent(region, ignored -> new HashMap<>()).put(player, playerTraceShowData);
         tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
             trace.render(player, playerTraceShowData);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(follower -> {
+                trace.render(follower, playerTraceShowData);
+            });
         });
     }
 
@@ -157,11 +179,56 @@ public class TraceManager implements Listener {
      * @param player
      */
     public void hide(Player player) {
+        unfollow(player);
+
         Region region = Region.getRegion(player.getLocation());
         PlayerTraceShowData previous = showDataPerRegionPerPlayer.getOrDefault(region, Collections.emptyMap()).remove(player);
         if (previous == null) return;
-        tracesByRegion.getOrDefault(player, Collections.emptyMap()).forEach((integer, trace) -> {
+        tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
             trace.hide(player);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(trace::hide);
+        });
+    }
+
+    public boolean hasFollower(Player player) {
+        return followerMap.containsKey(player);
+    }
+
+    public boolean follow(Player follower, Player following) {
+        if (followerMap.containsKey(follower)) return false;
+        followerMap.computeIfAbsent(following, ignored -> new HashSet<>()).add(follower);
+
+        showDataPerRegionPerPlayer.forEach((region, playerPlayerTraceShowDataMap) -> {
+            if (playerPlayerTraceShowDataMap.containsKey(follower)) {
+                tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
+                    trace.hide(follower);
+                });
+            }
+
+            PlayerTraceShowData playerTraceShowData = playerPlayerTraceShowDataMap.get(following);
+            if (playerTraceShowData == null) return;
+            tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
+                trace.render(follower, playerTraceShowData);
+            });
+        });
+        return true;
+    }
+
+    public void unfollow(Player follower) {
+        if (followerMap.containsKey(follower)) return;
+        List<Player> toRemove = new ArrayList<>();
+        followerMap.forEach((player, players) -> {
+            players.remove(player);
+            if (players.isEmpty()) toRemove.add(player);
+        });
+        toRemove.forEach(followerMap::remove);
+
+        showDataPerRegionPerPlayer.forEach((region, playerPlayerTraceShowDataMap) -> {
+            PlayerTraceShowData playerTraceShowData = playerPlayerTraceShowDataMap.get(follower);
+            if (playerTraceShowData == null) return;
+            tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
+                trace.render(follower, playerTraceShowData);
+            });
         });
     }
 
@@ -173,6 +240,8 @@ public class TraceManager implements Listener {
      * @param to     end of time interval
      */
     public void renderAt(Player player, int from, int to) {
+        unfollow(player);
+
         Region region = Region.getRegion(player.getLocation());
         PlayerTraceShowData playerTraceShowData = showDataPerRegionPerPlayer.computeIfAbsent(region, ignored -> new HashMap<>()).computeIfAbsent(player, ignored -> new PlayerTraceShowData(BundleFilter.STRICT));
 
@@ -186,6 +255,9 @@ public class TraceManager implements Listener {
 
         tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
             trace.render(player, playerTraceShowData);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(follower -> {
+                trace.render(follower, playerTraceShowData);
+            });
         });
     }
 
@@ -196,6 +268,8 @@ public class TraceManager implements Listener {
      * @param records the record for which isolation is toggled
      */
     public void isolate(Player player, TNTPoint... records) {
+        unfollow(player);
+
         Region region = Region.getRegion(player.getLocation());
         PlayerTraceShowData playerTraceShowData = showDataPerRegionPerPlayer.computeIfAbsent(region, ignored -> new HashMap<>()).computeIfAbsent(player, ignored -> new PlayerTraceShowData(BundleFilter.STRICT));
 
@@ -219,6 +293,9 @@ public class TraceManager implements Listener {
         PlayerTraceShowData finalPlayerTraceShowData = playerTraceShowData;
         tracesByRegion.getOrDefault(region, Collections.emptyMap()).forEach((integer, trace) -> {
             trace.render(player, finalPlayerTraceShowData);
+            followerMap.getOrDefault(player, Collections.emptySet()).forEach(follower -> {
+                trace.render(follower, finalPlayerTraceShowData);
+            });
         });
     }
 }