Added potion effects for switching tribes

src/main/java/com/minelittlepony/unicopia/Race.java

@@ -6,6 +6,8 @@ import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import javax.annotation.Nullable;
+
 import com.google.common.base.Strings;
 import com.minelittlepony.common.client.gui.sprite.TextureSprite;
 import com.minelittlepony.common.client.gui.style.Style;
@@ -80,7 +82,7 @@ public enum Race implements Affine {
         return String.format("unicopia.race.%s", name().toLowerCase());
     }
 
-    public boolean isPermitted(PlayerEntity sender) {
+    public boolean isPermitted(@Nullable PlayerEntity sender) {
         if (isOp() && (sender == null || !sender.abilities.creativeMode)) {
             return false;
         }

src/main/java/com/minelittlepony/unicopia/Unicopia.java

@@ -6,6 +6,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 import com.minelittlepony.unicopia.command.Commands;
+import com.minelittlepony.unicopia.entity.effect.UPotions;
 import com.minelittlepony.unicopia.item.UItems;
 import com.minelittlepony.unicopia.network.Channel;
 
@@ -35,5 +36,6 @@ public class Unicopia implements ModInitializer {
         ServerTickEvents.END_WORLD_TICK.register(AwaitTickQueue::tick);
 
         UItems.bootstrap();
+        UPotions.bootstrap();
     }
 }

src/main/java/com/minelittlepony/unicopia/entity/effect/RaceChangeStatusEffect.java

@@ -0,0 +1,146 @@
+package com.minelittlepony.unicopia.entity.effect;
+
+import javax.annotation.Nullable;
+
+import com.minelittlepony.unicopia.Race;
+import com.minelittlepony.unicopia.entity.Equine;
+import com.minelittlepony.unicopia.entity.PonyContainer;
+import com.minelittlepony.unicopia.entity.player.MagicReserves;
+import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.util.MagicalDamageSource;
+
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.damage.DamageSource;
+import net.minecraft.entity.effect.StatusEffect;
+import net.minecraft.entity.effect.StatusEffectInstance;
+import net.minecraft.entity.effect.StatusEffectType;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.particle.ParticleTypes;
+import net.minecraft.text.Text;
+import net.minecraft.text.TranslatableText;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.registry.Registry;
+
+public class RaceChangeStatusEffect extends StatusEffect {
+    public static final int STAGE_DURATION = 50;
+    public static final int MAX_DURATION = Stage.VALUES.length * STAGE_DURATION + 1;
+
+    public static final RaceChangeStatusEffect CHANGE_RACE_EARTH = new RaceChangeStatusEffect(0x886F0F, Race.EARTH);
+    public static final RaceChangeStatusEffect CHANGE_RACE_UNICORN = new RaceChangeStatusEffect(0x88FFFF, Race.UNICORN);
+    public static final RaceChangeStatusEffect CHANGE_RACE_PEGASUS = new RaceChangeStatusEffect(0x00FFFF, Race.PEGASUS);
+    public static final RaceChangeStatusEffect CHANGE_RACE_BAT = new RaceChangeStatusEffect(0x0FFF00, Race.BAT);
+    public static final RaceChangeStatusEffect CHANGE_RACE_CHANGELING = new RaceChangeStatusEffect(0xFFFF00, Race.CHANGELING);
+
+    private final Race species;
+
+    protected RaceChangeStatusEffect(int color, Race species) {
+        super(StatusEffectType.NEUTRAL, color);
+        this.species = species;
+
+        Registry.register(Registry.STATUS_EFFECT, new Identifier("unicopia", "change_race_" + species.name().toLowerCase()), this);
+    }
+
+    public Race getSpecies() {
+        return species;
+    }
+
+    @Override
+    public void applyUpdateEffect(LivingEntity entity, int amplifier) {
+        StatusEffectInstance state = entity.getStatusEffect(this);
+
+        if (state == null) {
+            return;
+        }
+
+        Equine<?> eq = Equine.of(entity);
+
+        if (eq == null) {
+            return;
+        }
+
+        int ticks = Math.max(0, MAX_DURATION - state.getDuration());
+
+        Stage stage = Stage.forDuration(ticks / STAGE_DURATION);
+
+        if (stage == Stage.INITIAL) {
+            return;
+        }
+
+        int progression = ticks % (stage.ordinal() * STAGE_DURATION);
+
+        if (eq.getSpecies() == species || !species.isPermitted(entity instanceof PlayerEntity ? (PlayerEntity)entity : null)) {
+            if (progression == 0 && entity instanceof PlayerEntity && stage == Stage.CRAWLING) {
+                ((PlayerEntity)entity).sendMessage(Stage.INITIAL.getMessage(species), true);
+            }
+            return;
+        }
+
+        if (progression == 0) {
+            if (stage != Stage.DEATH && entity instanceof PlayerEntity) {
+                ((PlayerEntity)entity).sendMessage(stage.getMessage(species), true);
+            }
+
+            float hitAmount = entity.getHealth() / 2;
+
+            if (hitAmount > 1) {
+                entity.damage(DamageSource.MAGIC, hitAmount);
+            }
+        }
+
+        if (entity instanceof PlayerEntity) {
+            Pony pony  = (Pony)eq;
+            MagicReserves magic = pony.getMagicalReserves();
+            magic.addExertion(50);
+            magic.addEnergy(3);
+
+            if (state.shouldShowParticles()) {
+                pony.spawnParticles(ParticleTypes.TOTEM_OF_UNDYING, 5);
+            }
+        }
+
+        if (stage == Stage.DEATH) {
+            PonyContainer.of(entity).map(PonyContainer::get).ifPresent(e -> {
+                e.setSpecies(species);
+                if (e instanceof Pony) {
+                    ((Pony)e).setDirty();
+                }
+            });
+            entity.damage(MagicalDamageSource.TRIBE_SWAP, Float.MAX_VALUE);
+        }
+    }
+
+    @Override
+    public void applyInstantEffect(@Nullable Entity source, @Nullable Entity attacker, LivingEntity target, int amplifier, double proximity) {
+        this.applyUpdateEffect(target, amplifier);
+    }
+
+    @Override
+    public boolean canApplyUpdateEffect(int duration, int amplifier) {
+        return duration > 0;
+    }
+
+    enum Stage {
+        INITIAL,
+        CRAWLING,
+        DETERMINATION,
+        RESURECTION,
+        DEATH;
+
+        static Stage[] VALUES = values();
+
+        public static Stage forDuration(int duration) {
+            return VALUES[duration % VALUES.length];
+        }
+
+        public String getTranslationKey() {
+            return String.format("unicopia.effect.tribe.stage.%s", name().toLowerCase());
+        }
+
+        public Text getMessage(Race species) {
+            return new TranslatableText(getTranslationKey(), new TranslatableText(species.getTranslationKey()));
+        }
+    }
+
+    static void bootstrap() { }
+}

src/main/java/com/minelittlepony/unicopia/entity/effect/UPotions.java

@@ -0,0 +1,26 @@
+package com.minelittlepony.unicopia.entity.effect;
+
+import net.minecraft.entity.effect.StatusEffectInstance;
+import net.minecraft.potion.Potion;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.registry.Registry;
+
+public interface UPotions {
+    Potion TRIBE_SWAP_EARTH_PONY = registerRacePotion(RaceChangeStatusEffect.CHANGE_RACE_EARTH);
+    Potion TRIBE_SWAP_UNICORN = registerRacePotion(RaceChangeStatusEffect.CHANGE_RACE_UNICORN);
+    Potion TRIBE_SWAP_PEGASUS = registerRacePotion(RaceChangeStatusEffect.CHANGE_RACE_PEGASUS);
+    Potion TRIBE_SWAP_BAT = registerRacePotion(RaceChangeStatusEffect.CHANGE_RACE_BAT);
+    Potion TRIBE_SWAP_CHANGELING = registerRacePotion(RaceChangeStatusEffect.CHANGE_RACE_CHANGELING);
+
+    static Potion registerRacePotion(RaceChangeStatusEffect effect) {
+        String name = "tribe_swap_" + effect.getSpecies().name().toLowerCase();
+        return register(name, new Potion("unicopia." + name,
+                new StatusEffectInstance(effect, RaceChangeStatusEffect.MAX_DURATION)));
+    }
+
+    static Potion register(String name, Potion potion) {
+        return Registry.register(Registry.POTION, new Identifier("unicopia", name), potion);
+    }
+
+    static void bootstrap() {}
+}

src/main/java/com/minelittlepony/unicopia/util/MagicalDamageSource.java

@@ -17,6 +17,7 @@ public class MagicalDamageSource extends EntityDamageSource {
 
     public static final DamageSource EXHAUSTION = new MagicalDamageSource("magical_exhaustion", true, true);
     public static final DamageSource FOOD_POISONING = mundane("food_poisoning");
+    public static final DamageSource TRIBE_SWAP = mundane("tribe_swap");
     public static final DamageSource ZAP_APPLE = create("zap");
 
     public static DamageSource mundane(String type) {

src/main/resources/assets/unicopia/lang/en_us.json

@@ -21,6 +21,41 @@
   "item.unicopia.music_disc_funk": "Music Disc",
   "item.unicopia.music_disc_funk.desc": "funk, just funk",
 
+  "unicopia.effect.tribe.stage.initial": "It appears to have no effect.",
+  "unicopia.effect.tribe.stage.crawling": "You feel the skin crawling on your back.",
+  "unicopia.effect.tribe.stage.determination": "As your bones realign you are filled determination.",
+  "unicopia.effect.tribe.stage.resurection": "Knowing you will return to this world as a %s",
+
+  "effect.unicopia.change_race_earth": "Earth Pony Metamorphosis",
+  "item.minecraft.potion.effect.unicopia.tribe_swap_earth": "Potion of Earth Pony Metamorphosis",
+  "item.minecraft.splash_potion.effect.unicopia.tribe_swap_earth": "Splash Potion of Earth Pony Metamorphosis",
+  "item.minecraft.lingering_potion.effect.unicopia.tribe_swap_earth": "Lingering Potion of Earth Pony Metamorphosis",
+  "item.minecraft.tipped_arrow.effect.unicopia.tribe_swap_earth": "Arrow of Earth Pony Metamorphosis",
+
+  "effect.unicopia.change_race_unicorn": "Unicorn Metamorphosis",
+  "item.minecraft.potion.effect.unicopia.tribe_swap_unicorn": "Potion of Unicorn Metamorphosis",
+  "item.minecraft.splash_potion.effect.unicopia.tribe_swap_unicorn": "Splash Potion of Unicorn Metamorphosis",
+  "item.minecraft.lingering_potion.effect.unicopia.tribe_swap_unicorn": "Lingering Potion of Unicorn Metamorphosis",
+  "item.minecraft.tipped_arrow.effect.unicopia.tribe_swap_unicorn": "Arrow of Unicorn Metamorphosis",
+
+  "effect.unicopia.change_race_pegasus": "Pegasus Metamorphosis",
+  "item.minecraft.potion.effect.unicopia.tribe_swap_pegasus": "Potion of Pegasus Metamorphosis",
+  "item.minecraft.splash_potion.effect.unicopia.tribe_swap_pegasus": "Splash Potion of Pegasus Metamorphosis",
+  "item.minecraft.lingering_potion.effect.unicopia.tribe_swap_pegasus": "Lingering Potion of Pegasus Metamorphosis",
+  "item.minecraft.tipped_arrow.effect.unicopia.tribe_swap_pegasus": "Arrow of Pegasus Metamorphosis",
+
+  "effect.unicopia.change_race_changeling": "Changeling Metamorphosis",
+  "item.minecraft.potion.effect.unicopia.tribe_swap_changeling": "Potion of Changeling Metamorphosis",
+  "item.minecraft.splash_potion.effect.unicopia.tribe_swap_changeling": "Splash Potion of Changeling Metamorphosis",
+  "item.minecraft.lingering_potion.effect.unicopia.tribe_swap_changeling": "Lingering Potion of Changeling Metamorphosis",
+  "item.minecraft.tipped_arrow.effect.unicopia.tribe_swap_changeling": "Arrow of Changeling Metamorphosis",
+  
+  "effect.unicopia.change_race_bat": "Bat Pony Metamorphosis",
+  "item.minecraft.potion.effect.unicopia.tribe_swap_bat": "Potion of Bat Pony Metamorphosis",
+  "item.minecraft.splash_potion.effect.unicopia.tribe_swap_bat": "Splash Potion of Bat Pony Metamorphosis",
+  "item.minecraft.lingering_potion.effect.unicopia.tribe_swap_bat": "Lingering Potion of Bat Pony Metamorphosis",
+  "item.minecraft.tipped_arrow.effect.unicopia.tribe_swap_bat": "Arrow of Bat Pony Metamorphosis",
+
   "affinity.good": "Pure",
   "affinity.neutral": "Neutral",
   "affinity.curse": "Corrupt",
@@ -178,6 +213,7 @@
   "key.unicopia.tertiary": "Tertiary Ability",
   "key.unicopia.passive": "Passive Ability",
 
+  "death.attack.tribe_swap": "%1$s was reborn into a different tribe",
   "death.attack.magical_exhaustion": "%1$s exhausted themselves",
   "death.attack.alicorn_amulet": "%1$s was driven insane",
   "death.attack.darkness": "%1$s went missing",