new filters for entities

docs/scarpet/api/Entities.md

@@ -29,21 +29,46 @@ but obviously using UUIDs takes more memory and compute.
 Returns global lists of entities in the current dimension of a specified type. Currently the following 
 selectors are available:
 
-*   `*`: all entites
-*   `living`
-*   `items`
-*   `players`
-*   `!players`
+*  `*`: all entities, even `!valid`
+*  `valid` - all entities that are not dead (health > 0). All main categories below also return only 
+entities in the `valid` category.
+*  `living` - all entities that resemble a creature of any sort
+*  `projectile` - all entities that are not living that can be throw or projected
+*  `undead`, `arthropod`, `aquatic`, `regular`, `illager` - all entities that belong to any of these groups. Every 
+living entity belongs to one and only one of these.
+*  `monster`, `creature`, `ambient`, `water_creature`, `water_ambient`, `misc` - another categorization of 
+living entites based on their spawn group.
+*  Any of the following standard entity types (equivalent to selection from `/summon` vanilla command: 
+`area_effect_cloud`, `armor_stand`, `arrow`, `bat`, `bee`, `blaze`, `boat`, `cat`, `cave_spider`, `chest_minecart`, 
+`chicken`, `cod`, `command_block_minecart`, `cow`, `creeper`, `dolphin`, `donkey`, `dragon_fireball`, `drowned`, `egg`,
+`elder_guardian`, `end_crystal`, `ender_dragon`, `ender_pearl`, `enderman`, `endermite`, `evoker`, `evoker_fangs`,
+`experience_bottle`, `experience_orb`, `eye_of_ender`, `falling_block`, `fireball`, `firework_rocket`, 
+`fishing_bobber`, `fox`, `furnace_minecart`, `ghast`, `giant`, `guardian`, `hopper_minecart`, `horse`, `husk`,
+`illusioner`, `iron_golem`, `item`, `item_frame`, `leash_knot`, `lightning_bolt`, `llama`, `llama_spit`, 
+`magma_cube`, `minecart`, `mooshroom`, `mule`, `ocelot`, `painting`, `panda`, `parrot`, `phantom`, `pig`, `pillager`, 
+`player`, `polar_bear`, `potion`, `pufferfish`, `rabbit`, `ravager`, `salmon`, `sheep`, `shulker`, `shulker_bullet`, 
+`silverfish`, `skeleton`, `skeleton_horse`, `slime`, `small_fireball`, `snow_golem`, `snowball`, `spawner_minecart`, 
+`spectral_arrow`, `spider`, `squid`, `stray`, `tnt`, `tnt_minecart`, `trader_llama`, `trident`, `tropical_fish`, 
+`turtle`, `vex`, `villager`, `vindicator`, `wandering_trader`, `witch`, `wither`, `wither_skeleton`, `wither_skull`, 
+`wolf`, `zombie`, `zombie_horse`, `zombie_pigman`, `zombie_villager`
+
+All categories can be preceeded with `'!'` which will fetch all entites that are valid (health > 0) but not belonging to
+that group. Calls to `entity_list` always fetch entites from the current world that the script executes. 
 
 ### `entity_area(type, cx, cy, cz, dx, dy, dz)`
 
 Returns entities of a specified type in an area centered on `cx, cy, cz` and at most `dx, dy, dz` blocks away from 
 the center point. Uses the same selectors as `entities_list`.
 
+entity_area is simpler than `entity_selector` and runs about 20% faster, but is limited to predefined selectors and 
+cuboid search area.
+
 ### `entity_selector(selector)`
 
 Returns entities satisifying given vanilla entity selector. Most complex among all the methods of selecting entities, 
-but the most capable. Selectors are cached so it should be as fast as other methods of selecting entities.
+but the most capable. Selectors are cached so it should be as fast as other methods of selecting entities. Unlike other
+entities fetching / filtering method, this one doesn't guarantee to return entities from current dimension, since
+selectors can return any loaded entity in the world.
 
 ### `spawn(name, pos, nbt?)`
 

src/main/java/carpet/script/value/EntityValue.java

@@ -12,10 +12,14 @@ import carpet.script.CarpetContext;
 import carpet.script.EntityEventsGroup;
 import carpet.script.argument.Vector3Argument;
 import carpet.script.exception.InternalExpressionException;
+import com.google.common.collect.ImmutableMap;
 import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import net.minecraft.entity.EntityCategory;
+import net.minecraft.entity.EntityGroup;
 import net.minecraft.entity.ai.brain.MemoryModuleType;
 import net.minecraft.entity.ai.pathing.Path;
+import net.minecraft.entity.projectile.Projectile;
 import net.minecraft.nbt.StringTag;
 import net.minecraft.nbt.Tag;
 import net.minecraft.network.packet.s2c.play.EntityPassengersSetS2CPacket;
@@ -191,14 +195,47 @@ public class EntityValue extends Value
         return res; //TODO add more here like search by tags, or type
         //if (who.startsWith('tag:'))
     }
+
+    private static Map<String, EntityGroup> entityGroupMap = ImmutableMap.of(
+            "undead", EntityGroup.UNDEAD,
+            "arthropod", EntityGroup.ARTHROPOD,
+            "aquatic", EntityGroup.AQUATIC,
+            "regular", EntityGroup.DEFAULT,
+            "illager", EntityGroup.ILLAGER
+    );
+
     private static final Map<String, Pair<EntityType<?>, Predicate<? super Entity>>> entityPredicates =
             new HashMap<String, Pair<EntityType<?>, Predicate<? super Entity>>>()
     {{
-        put("*", Pair.of(null, EntityPredicates.VALID_ENTITY));
+        put("*", Pair.of(null, e -> true));
+        put("valid", Pair.of(null, EntityPredicates.VALID_ENTITY));
+        put("!valid", Pair.of(null, e -> !e.isAlive()));
+
         put("living", Pair.of(null, (e) -> e instanceof LivingEntity && e.isAlive()));
-        put("items", Pair.of(EntityType.ITEM, EntityPredicates.VALID_ENTITY));
-        put("players", Pair.of(EntityType.PLAYER, EntityPredicates.VALID_ENTITY));
-        put("!players", Pair.of(null, (e) -> !(e instanceof PlayerEntity) ));
+        put("!living", Pair.of(null, (e) -> !(e instanceof LivingEntity) && e.isAlive()));
+
+        put("projectile", Pair.of(null, (e) -> e instanceof Projectile && e.isAlive()));
+        put("!projectile", Pair.of(null, (e) -> !(e instanceof Projectile) && e.isAlive()));
+
+        for (String groupStr : entityGroupMap.keySet())
+        {
+            EntityGroup group = entityGroupMap.get(groupStr);
+            put(    groupStr, Pair.of(null,  e -> ((e instanceof LivingEntity) && ((LivingEntity) e).getGroup() == group && e.isAlive())));
+            put("!"+groupStr, Pair.of(null,  e -> ((e instanceof LivingEntity) && ((LivingEntity) e).getGroup() != group && e.isAlive())));
+        }
+        for (Identifier typeId : Registry.ENTITY_TYPE.getIds())
+        {
+            EntityType type  = Registry.ENTITY_TYPE.get(typeId);
+            String mobType = ValueConversions.simplify(typeId);
+            put(    mobType, Pair.of(type, EntityPredicates.VALID_ENTITY));
+            put("!"+mobType, Pair.of(null, (e) -> e.getType() != type  && e.isAlive()));
+        }
+        for (EntityCategory catId : EntityCategory.values())
+        {
+            String catStr = catId.getName();
+            put(    catStr, Pair.of(null, e -> (e.getType().getCategory() == catId) && e.isAlive()));
+            put("!"+catStr, Pair.of(null, e -> (e.getType().getCategory() != catId) && e.isAlive()));
+        }
     }};
     public Value get(String what, Value arg)
     {

src/main/java/carpet/script/value/ValueConversions.java

@@ -45,6 +45,16 @@ public class ValueConversions
             return new StringValue(id.getPath());
         return new StringValue(id.toString());
     }
+
+    public static String simplify(Identifier id)
+    {
+        if (id == null) // should be Value.NULL
+            return "";
+        if (id.getNamespace().equals("minecraft"))
+            return id.getPath();
+        return id.toString();
+    }
+
     public static Value ofGlobalPos(GlobalPos pos)
     {
         return ListValue.of(