fix issues related to airborne positioning

src/main/java/net/fretux/adaptivemobs/ai/goals/AdaptiveAirbornePositioningGoal.java

@@ -4,9 +4,11 @@ import net.fretux.adaptivemobs.ai.AdaptiveAIGoalUtils;
 import net.fretux.adaptivemobs.ai.AdaptivePositioningUtils;
 import net.fretux.adaptivemobs.ai.AdaptiveTargetingUtils;
 import net.fretux.adaptivemobs.config.AMConfig;
+import net.minecraft.core.BlockPos;
 import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.Mob;
 import net.minecraft.world.entity.ai.goal.Goal;
+import net.minecraft.world.phys.AABB;
 import net.minecraft.world.phys.Vec3;
 
 import java.util.EnumSet;
@@ -14,6 +16,8 @@ import java.util.function.IntSupplier;
 
 public class AdaptiveAirbornePositioningGoal extends Goal {
 
+    private static final double MIN_REPOSITION_DISTANCE_SQR = 4.0D;
+
     private final Mob mob;
     private final IntSupplier tierSupplier;
     private final double range;
@@ -25,7 +29,7 @@ public class AdaptiveAirbornePositioningGoal extends Goal {
         this.tierSupplier = tierSupplier;
         this.range = range;
         this.verticalOffset = verticalOffset;
-        setFlags(EnumSet.of(Flag.MOVE, Flag.LOOK));
+        setFlags(EnumSet.of(Flag.MOVE));
     }
 
     @Override
@@ -37,16 +41,49 @@ public class AdaptiveAirbornePositioningGoal extends Goal {
     public void start() {
         cooldown = AdaptiveAIGoalUtils.nextCooldown(mob);
         LivingEntity target = mob.getTarget();
-        if (target == null) {
+        if (target == null || !target.isAlive()) {
             return;
         }
         int tier = tierSupplier.getAsInt();
         boolean spread = tier >= 4 && AdaptiveTargetingUtils.nearbyAttackers(mob, target, range) > 1;
         double lead = tier >= 5 ? AMConfig.tierValue(AMConfig.AI_INTERCEPTION_STRENGTH.get(), tier) : 0.0D;
-        Vec3 dest = AdaptivePositioningUtils.sidePosition(mob, target, range,
+        Vec3 preferred = AdaptivePositioningUtils.sidePosition(mob, target, range,
                 spread && mob.getRandom().nextBoolean() ? -1.0D : 1.0D, lead).add(0.0D, verticalOffset, 0.0D);
+        Vec3 dest = safeDestination(preferred);
+        if (dest == null || mob.position().distanceToSqr(dest) < MIN_REPOSITION_DISTANCE_SQR) {
+            return;
+        }
         mob.getMoveControl().setWantedPosition(dest.x, dest.y, dest.z, 1.0D);
-        mob.getLookControl().setLookAt(target, 30.0F, 30.0F);
         AdaptiveAIGoalUtils.debug(mob, tierSupplier, "airborne reposition");
     }
+
+    private Vec3 safeDestination(Vec3 preferred) {
+        double minY = mob.level().getMinBuildHeight() + 1.0D;
+        double maxY = mob.level().getMaxBuildHeight() - Math.max(1.0D, mob.getBbHeight());
+        double y = Math.max(minY, Math.min(maxY, preferred.y));
+        Vec3 base = new Vec3(preferred.x, y, preferred.z);
+        if (isClear(base)) {
+            return base;
+        }
+        for (int offset = 1; offset <= 4; offset++) {
+            Vec3 above = base.add(0.0D, offset, 0.0D);
+            if (above.y <= maxY && isClear(above)) {
+                return above;
+            }
+            Vec3 below = base.add(0.0D, -offset, 0.0D);
+            if (below.y >= minY && isClear(below)) {
+                return below;
+            }
+        }
+        return null;
+    }
+
+    private boolean isClear(Vec3 pos) {
+        BlockPos blockPos = BlockPos.containing(pos);
+        if (!mob.level().getWorldBorder().isWithinBounds(blockPos)) {
+            return false;
+        }
+        AABB movedBox = mob.getBoundingBox().move(pos.subtract(mob.position()));
+        return mob.level().noCollision(mob, movedBox);
+    }
 }