Add local position provider

Author: ErrorCraft

src/main/java/errorcraft/entitymodifiers/world/position/provider/PositionProviderTypes.java

@@ -1,6 +1,7 @@
 package errorcraft.entitymodifiers.world.position.provider;
 
 import errorcraft.entitymodifiers.mixin.registry.RegistryAccessor;
+import errorcraft.entitymodifiers.world.position.provider.providers.LocalPositionProvider;
 import errorcraft.entitymodifiers.world.position.provider.providers.WorldPositionProvider;
 import net.minecraft.util.Identifier;
 import net.minecraft.util.JsonSerializing;
@@ -12,6 +13,7 @@ public class PositionProviderTypes {
     public static final Registry<PositionProviderType> POSITION_PROVIDER_TYPE = RegistryAccessor.create(POSITION_PROVIDER_TYPE_KEY, registry -> PositionProviderTypes.WORLD);
 
     public static final PositionProviderType WORLD = register("world", new WorldPositionProvider.Serialiser());
+    public static final PositionProviderType LOCAL = register("local", new LocalPositionProvider.Serialiser());
 
     public static Object createGsonAdapter() {
         return JsonSerializing.createSerializerBuilder(POSITION_PROVIDER_TYPE, "type", "type", PositionProvider::getType).build();

src/main/java/errorcraft/entitymodifiers/world/position/provider/providers/LocalPositionProvider.java

@@ -0,0 +1,59 @@
+package errorcraft.entitymodifiers.world.position.provider.providers;
+
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonSerializationContext;
+import errorcraft.entitymodifiers.world.position.provider.PositionProvider;
+import errorcraft.entitymodifiers.world.position.provider.PositionProviderType;
+import errorcraft.entitymodifiers.world.position.provider.PositionProviderTypes;
+import net.minecraft.command.argument.LookingPosArgument;
+import net.minecraft.loot.context.LootContext;
+import net.minecraft.loot.provider.number.LootNumberProvider;
+import net.minecraft.server.command.ServerCommandSource;
+import net.minecraft.util.JsonHelper;
+import net.minecraft.util.math.Vec2f;
+import net.minecraft.util.math.Vec3d;
+
+public class LocalPositionProvider implements PositionProvider {
+    private final LootNumberProvider left;
+    private final LootNumberProvider up;
+    private final LootNumberProvider forwards;
+
+    public LocalPositionProvider(LootNumberProvider left, LootNumberProvider up, LootNumberProvider forwards) {
+        this.left = left;
+        this.up = up;
+        this.forwards = forwards;
+    }
+
+    @Override
+    public PositionProviderType getType() {
+        return PositionProviderTypes.LOCAL;
+    }
+
+    @Override
+    public Vec3d getPosition(Vec3d currentPosition, Vec2f rotation, LootContext lootContext) {
+        double leftOffset = this.left.nextFloat(lootContext);
+        double upOffset = this.up.nextFloat(lootContext);
+        double forwardsOffset = this.forwards.nextFloat(lootContext);
+        LookingPosArgument argument = new LookingPosArgument(leftOffset, upOffset, forwardsOffset);
+        ServerCommandSource commandSource = new ServerCommandSource(null, currentPosition, rotation, null, 0, null, null, null, null);
+        return argument.toAbsolutePos(commandSource);
+    }
+
+    public static class Serialiser implements PositionProvider.Serialiser<LocalPositionProvider> {
+        @Override
+        public void toJson(JsonObject json, LocalPositionProvider object, JsonSerializationContext context) {
+            json.add("left", context.serialize(object.left));
+            json.add("up", context.serialize(object.up));
+            json.add("forwards", context.serialize(object.forwards));
+        }
+
+        @Override
+        public LocalPositionProvider fromJson(JsonObject json, JsonDeserializationContext context) {
+            LootNumberProvider left = JsonHelper.deserialize(json, "left", context, LootNumberProvider.class);
+            LootNumberProvider up = JsonHelper.deserialize(json, "up", context, LootNumberProvider.class);
+            LootNumberProvider forwards = JsonHelper.deserialize(json, "forwards", context, LootNumberProvider.class);
+            return new LocalPositionProvider(left, up, forwards);
+        }
+    }
+}