Refactor CancelReason event firing, NPCs should teleport if no path can be found

src/main/java/net/citizensnpcs/npc/ai/CitizensNavigator.java

@@ -25,8 +25,10 @@ public class CitizensNavigator implements Navigator {
             .range(Setting.DEFAULT_PATHFINDING_RANGE.asFloat())
             .stationaryTicks(Setting.DEFAULT_STATIONARY_TICKS.asInt());
     private PathStrategy executing;
+    int lastX, lastY, lastZ;
     private NavigatorParameters localParams = defaultParams;
     private final CitizensNPC npc;
+
     private int stationaryTicks;
 
     private boolean updatedAvoidWater = false;
@@ -37,9 +39,7 @@ public class CitizensNavigator implements Navigator {
 
     @Override
     public void cancelNavigation() {
-        if (isNavigating())
+        stopNavigating(CancelReason.PLUGIN);
-            Bukkit.getPluginManager().callEvent(new NavigationCancelEvent(this, CancelReason.PLUGIN));
-        stopNavigating();
     }
 
     @Override
@@ -138,6 +138,18 @@ public class CitizensNavigator implements Navigator {
         stationaryTicks = 0;
     }
 
+    private void stopNavigating(CancelReason reason) {
+        if (!isNavigating())
+            return;
+        if (reason == CancelReason.STUCK) {
+            StuckAction action = localParams.stuckAction();
+            if (action != null)
+                action.run(npc, this);
+        }
+        Bukkit.getPluginManager().callEvent(new NavigationCancelEvent(this, reason));
+        stopNavigating();
+    }
+
     private void switchStrategyTo(PathStrategy newStrategy) {
         if (executing != null)
             Bukkit.getPluginManager().callEvent(new NavigationReplaceEvent(this));
@@ -150,7 +162,11 @@ public class CitizensNavigator implements Navigator {
         if (!isNavigating() || !npc.isSpawned() || updateStationaryStatus())
             return;
         boolean finished = executing.update();
-        if (finished) {
+        if (!finished)
+            return;
+        if (executing.getCancelReason() != null)
+            stopNavigating(executing.getCancelReason());
+        else {
             Bukkit.getPluginManager().callEvent(new NavigationCompleteEvent(this));
             stopNavigating();
         }
@@ -160,19 +176,13 @@ public class CitizensNavigator implements Navigator {
         NMS.updatePathfindingRange(npc, localParams.range());
     }
 
-    int lastX, lastY, lastZ;
-
     private boolean updateStationaryStatus() {
         if (localParams.stationaryTicks() < 0)
             localParams.stationaryTicks(100);// return false;
         EntityLiving handle = npc.getHandle();
         if (lastX == (int) handle.locX && lastY == (int) handle.locY && lastZ == (int) handle.locZ) {
             if (++stationaryTicks >= localParams.stationaryTicks()) {
-                StuckAction action = localParams.stuckAction();
+                stopNavigating(CancelReason.STUCK);
-                if (action != null)
-                    action.run(npc, this);
-                Bukkit.getPluginManager().callEvent(new NavigationCancelEvent(this, CancelReason.STUCK));
-                stopNavigating();
                 return true;
             }
         } else

src/main/java/net/citizensnpcs/npc/ai/MCNavigationStrategy.java

@@ -2,6 +2,7 @@ package net.citizensnpcs.npc.ai;
 
 import net.citizensnpcs.api.ai.NavigatorParameters;
 import net.citizensnpcs.api.ai.TargetType;
+import net.citizensnpcs.api.ai.event.CancelReason;
 import net.citizensnpcs.npc.CitizensNPC;
 import net.minecraft.server.EntityPlayer;
 import net.minecraft.server.Navigation;
@@ -9,6 +10,7 @@ import net.minecraft.server.Navigation;
 import org.bukkit.Location;
 
 public class MCNavigationStrategy implements PathStrategy {
+    private CancelReason cancelReason;
     private final Navigation navigation;
     private final NavigatorParameters parameters;
     private final Location target;
@@ -25,6 +27,12 @@ public class MCNavigationStrategy implements PathStrategy {
         navigation = npc.getHandle().getNavigation();
         navigation.a(parameters.avoidWater());
         navigation.a(dest.getX(), dest.getY(), dest.getZ(), parameters.speed());
+        if (navigation.f())
+            cancelReason = CancelReason.STUCK;
+    }
+
+    public CancelReason getCancelReason() {
+        return cancelReason;
     }
 
     @Override

src/main/java/net/citizensnpcs/npc/ai/MCTargetStrategy.java

@@ -3,6 +3,7 @@ package net.citizensnpcs.npc.ai;
 import net.citizensnpcs.api.ai.EntityTarget;
 import net.citizensnpcs.api.ai.NavigatorParameters;
 import net.citizensnpcs.api.ai.TargetType;
+import net.citizensnpcs.api.ai.event.CancelReason;
 import net.citizensnpcs.npc.CitizensNPC;
 import net.citizensnpcs.util.Util;
 import net.minecraft.server.EntityLiving;
@@ -18,6 +19,7 @@ import org.bukkit.entity.LivingEntity;
 public class MCTargetStrategy implements PathStrategy, EntityTarget {
     private final boolean aggro;
     private int attackTicks;
+    private CancelReason cancelReason;
     private final EntityLiving handle, target;
     private final Navigation navigation;
     private final NavigatorParameters parameters;
@@ -41,6 +43,11 @@ public class MCTargetStrategy implements PathStrategy, EntityTarget {
         return handle.getBukkitEntity().getLocation().distanceSquared(target.getBukkitEntity().getLocation());
     }
 
+    @Override
+    public CancelReason getCancelReason() {
+        return cancelReason;
+    }
+
     @Override
     public LivingEntity getTarget() {
         return (LivingEntity) target.getBukkitEntity();
@@ -68,8 +75,12 @@ public class MCTargetStrategy implements PathStrategy, EntityTarget {
 
     @Override
     public boolean update() {
-        if (target == null || target.dead)
+        if (target == null)
             return true;
+        if (target.dead) {
+            cancelReason = CancelReason.TARGET_DIED;
+            return true;
+        }
         navigation.a(target, parameters.speed());
         handle.getControllerLook().a(target, 10.0F, handle.bf());
         if (aggro && canAttack()) {

src/main/java/net/citizensnpcs/npc/ai/PathStrategy.java

@@ -1,10 +1,13 @@
 package net.citizensnpcs.npc.ai;
 
 import net.citizensnpcs.api.ai.TargetType;
+import net.citizensnpcs.api.ai.event.CancelReason;
 
 import org.bukkit.Location;
 
 public interface PathStrategy {
+    CancelReason getCancelReason();
+
     Location getTargetAsLocation();
 
     TargetType getTargetType();