Add arcane protection spell

src/main/java/com/minelittlepony/unicopia/ability/UnicornCastingAbility.java

@@ -52,6 +52,9 @@ public class UnicornCastingAbility implements Ability<Hit> {
     @Override
     @Nullable
     public Hit tryActivate(Pony player) {
+        if (!player.canCast()) {
+            return null;
+        }
         return Hit.of(player.getMagicalReserves().getMana().get() >= getCostEstimate(player));
     }
 
@@ -77,6 +80,10 @@ public class UnicornCastingAbility implements Ability<Hit> {
 
     @Override
     public void apply(Pony player, Hit data) {
+        if (!player.canCast()) {
+            return;
+        }
+
         TypedActionResult<ItemStack> amulet = getAmulet(player);
 
         if (amulet.getResult().isAccepted()) {

src/main/java/com/minelittlepony/unicopia/ability/UnicornTeleportAbility.java

@@ -66,6 +66,11 @@ public class UnicornTeleportAbility implements Ability<Pos> {
 
     @Override
     public Pos tryActivate(Pony player) {
+
+        if (!player.canCast()) {
+            return null;
+        }
+
         int maxDistance = player.getMaster().isCreative() ? 1000 : 100;
         HitResult ray = RayTraceHelper.doTrace(player.getMaster(), maxDistance, 1, EntityPredicates.EXCEPT_CREATIVE_OR_SPECTATOR).getResult();
 
@@ -130,6 +135,10 @@ public class UnicornTeleportAbility implements Ability<Pos> {
 
     protected void teleport(Pony teleporter, Caster<?> teleportee, Pos destination) {
 
+        if (!teleporter.canCast()) {
+            return;
+        }
+
         LivingEntity player = teleportee.getMaster();
 
         if (player == null) {

src/main/java/com/minelittlepony/unicopia/ability/magic/Caster.java

@@ -8,6 +8,7 @@ import org.jetbrains.annotations.Nullable;
 
 import com.minelittlepony.unicopia.EquinePredicates;
 import com.minelittlepony.unicopia.Owned;
+import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
 import com.minelittlepony.unicopia.entity.Physics;
 import com.minelittlepony.unicopia.entity.PonyContainer;
 import com.minelittlepony.unicopia.particle.ParticleSource;
@@ -18,6 +19,7 @@ import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.sound.SoundEvent;
 import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.GameRules;
 import net.minecraft.world.World;
 
@@ -61,6 +63,11 @@ public interface Caster<E extends LivingEntity> extends Owned<E>, Levelled, Affi
     }
 
     default boolean canModifyAt(BlockPos pos) {
+
+        if (!canCastAt(Vec3d.ofCenter(pos))) {
+            return false;
+        }
+
         if (getMaster() instanceof PlayerEntity) {
             return getReferenceWorld().canPlayerModifyAt((PlayerEntity)getMaster(), pos);
         }
@@ -94,6 +101,18 @@ public interface Caster<E extends LivingEntity> extends Owned<E>, Levelled, Affi
         return findAllEntitiesInRange(radius, null);
     }
 
+    default boolean canCast() {
+        return canCastAt(getOriginVector());
+    }
+
+    default boolean canCastAt(Vec3d pos) {
+        return findAllSpellsInRange(500, SpellType.ARCANE_PROTECTION::isOn).noneMatch(caster -> caster
+                .getSpellSlot().get(SpellType.ARCANE_PROTECTION, false)
+                .filter(spell -> spell.blocksMagicFor(caster, this, pos))
+                .isPresent()
+        );
+    }
+
     static Stream<Caster<?>> stream(Stream<Entity> entities) {
         return entities.map(Caster::of).flatMap(Optional::stream);
     }

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/AreaProtectionSpell.java

@@ -0,0 +1,75 @@
+package com.minelittlepony.unicopia.ability.magic.spell.effect;
+
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.ability.magic.spell.AbstractAreaEffectSpell;
+import com.minelittlepony.unicopia.ability.magic.spell.Situation;
+import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
+import com.minelittlepony.unicopia.ability.magic.spell.trait.Trait;
+import com.minelittlepony.unicopia.entity.UEntities;
+import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.item.FriendshipBraceletItem;
+import com.minelittlepony.unicopia.particle.MagicParticleEffect;
+import com.minelittlepony.unicopia.util.shape.Sphere;
+
+import net.minecraft.entity.Entity;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Vec3d;
+
+public class AreaProtectionSpell extends AbstractAreaEffectSpell {
+    public static final SpellTraits DEFAULT_TRAITS = new SpellTraits.Builder()
+            .with(Trait.FOCUS, 50)
+            .with(Trait.STRENGTH, 30)
+            .build();
+
+    protected AreaProtectionSpell(CustomisedSpellType<?> type) {
+        super(type);
+    }
+
+    @Override
+    public boolean tick(Caster<?> source, Situation situation) {
+
+        if (situation == Situation.PROJECTILE || situation == Situation.BODY) {
+            return false;
+        }
+
+        float radius = (float)getDrawDropOffRange(source);
+
+        if (source.isClient()) {
+            Vec3d origin = source.getOriginVector();
+
+            source.spawnParticles(origin, new Sphere(true, radius), (int)(radius * 6), pos -> {
+                if (!source.getReferenceWorld().isAir(new BlockPos(pos))) {
+                    source.addParticle(new MagicParticleEffect(getType().getColor()), pos, Vec3d.ZERO);
+                }
+            });
+        }
+
+        source.findAllSpellsInRange(radius, e -> isValidTarget(source, e)).filter(caster -> !caster.hasCommonOwner(source)).forEach(caster -> {
+            caster.getEntity().kill();
+        });
+
+        return !isDead();
+    }
+
+    /**
+     * Calculates the maximum radius of the shield. aka The area of effect.
+     */
+    public double getDrawDropOffRange(Caster<?> source) {
+        float multiplier = source instanceof Pony pony && pony.getMaster().isSneaking() ? 1 : 2;
+        float min = 4 + getTraits().get(Trait.POWER);
+        double range = (min + (source.getLevel().getScaled(4) * 2)) / multiplier;
+        if (source instanceof Pony && range > 2) {
+            range = Math.sqrt(range);
+        }
+        return range;
+    }
+
+    public boolean blocksMagicFor(Caster<?> source, Caster<?> other, Vec3d position) {
+        return !FriendshipBraceletItem.isComrade(other, other.getEntity())
+                && source.getOriginVector().distanceTo(position) <= getDrawDropOffRange(source);
+    }
+
+    protected boolean isValidTarget(Caster<?> source, Entity entity) {
+        return entity.getType() == UEntities.MAGIC_BEAM;
+    }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/SpellType.java

@@ -50,13 +50,14 @@ public final class SpellType<T extends Spell> implements Affine, SpellPredicate<
     public static final SpellType<FireSpell> FLAME = register("flame", Affinity.GOOD, 0xFFBB99, true, FireSpell.DEFAULT_TRAITS, FireSpell::new);
     public static final SpellType<InfernoSpell> INFERNAL = register("infernal", Affinity.BAD, 0xFFAA00, true, InfernoSpell.DEFAULT_TRAITS, InfernoSpell::new);
     public static final SpellType<ShieldSpell> SHIELD = register("shield", Affinity.NEUTRAL, 0x66CDAA, true, ShieldSpell.DEFAULT_TRAITS, ShieldSpell::new);
+    public static final SpellType<AreaProtectionSpell> ARCANE_PROTECTION = register("arcane_protection", Affinity.BAD, 0x99CDAA, true, AreaProtectionSpell.DEFAULT_TRAITS, AreaProtectionSpell::new);
     public static final SpellType<AttractiveSpell> VORTEX = register("vortex", Affinity.NEUTRAL, 0xFFEA88, true, AttractiveSpell.DEFAULT_TRAITS, AttractiveSpell::new);
     public static final SpellType<DarkVortexSpell> DARK_VORTEX = register("dark_vortex", Affinity.BAD, 0xA33333, true, DarkVortexSpell.DEFAULT_TRAITS, DarkVortexSpell::new);
-    public static final SpellType<NecromancySpell> NECROMANCY = register("necromancy", Affinity.BAD, 0xFA3A3A, true, NecromancySpell::new);
+    public static final SpellType<NecromancySpell> NECROMANCY = register("necromancy", Affinity.BAD, 0xFA3A3A, true, SpellTraits.EMPTY, NecromancySpell::new);
-    public static final SpellType<SiphoningSpell> SIPHONING = register("siphoning", Affinity.NEUTRAL, 0xFFA3AA, true, SiphoningSpell::new);
+    public static final SpellType<SiphoningSpell> SIPHONING = register("siphoning", Affinity.NEUTRAL, 0xFFA3AA, true, SpellTraits.EMPTY, SiphoningSpell::new);
-    public static final SpellType<DisperseIllusionSpell> REVEALING = register("reveal", Affinity.GOOD, 0xFFFFAF, true, DisperseIllusionSpell::new);
+    public static final SpellType<DisperseIllusionSpell> REVEALING = register("reveal", Affinity.GOOD, 0xFFFFAF, true, SpellTraits.EMPTY, DisperseIllusionSpell::new);
-    public static final SpellType<AwkwardSpell> AWKWARD = register("awkward", Affinity.GOOD, 0x3A59FF, true, AwkwardSpell::new);
+    public static final SpellType<AwkwardSpell> AWKWARD = register("awkward", Affinity.GOOD, 0x3A59FF, true, SpellTraits.EMPTY, AwkwardSpell::new);
-    public static final SpellType<TransformationSpell> TRANSFORMATION = register("transformation", Affinity.GOOD, 0x19E48E, true, TransformationSpell::new);
+    public static final SpellType<TransformationSpell> TRANSFORMATION = register("transformation", Affinity.GOOD, 0x19E48E, true, SpellTraits.EMPTY, TransformationSpell::new);
     public static final SpellType<FeatherFallSpell> FEATHER_FALL = register("feather_fall", Affinity.GOOD, 0x00EEFF, true, FeatherFallSpell.DEFAULT_TRAITS, FeatherFallSpell::new);
     public static final SpellType<CatapultSpell> CATAPULT = register("catapult", Affinity.GOOD, 0x22FF00, true, CatapultSpell.DEFAULT_TRAITS, CatapultSpell::new);
     public static final SpellType<FireBoltSpell> FIRE_BOLT = register("fire_bolt", Affinity.GOOD, 0xFF8811, true, FireBoltSpell.DEFAULT_TRAITS, FireBoltSpell::new);
@@ -159,11 +160,6 @@ public final class SpellType<T extends Spell> implements Affine, SpellPredicate<
         return "SpellType[" + getTranslationKey() + "]";
     }
 
-    @Deprecated(forRemoval = true)
-    public static <T extends Spell> SpellType<T> register(String name, Affinity affinity, int color, boolean obtainable, Factory<T> factory) {
-        return register(name, affinity, color, obtainable, SpellTraits.EMPTY, factory);
-    }
-
     public static <T extends Spell> SpellType<T> register(String name, Affinity affinity, int color, boolean obtainable, SpellTraits traits, Factory<T> factory) {
         return register(Unicopia.id(name), affinity, color, obtainable, traits, factory);
     }

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

@@ -146,6 +146,8 @@
   "spell.unicopia.fire_bolt.lore": "Produces several burning projectiles",
   "spell.unicopia.shield": "Protection",
   "spell.unicopia.shield.lore": "Casts a protective shield around the user",
+  "spell.unicopia.arcane_protection": "Arcane Protections",
+  "spell.unicopia.arcane_protection.lore": "Creates a protective shroud over an area in which no other spells can be cast",
   "spell.unicopia.vortex": "Arcane Attraction",
   "spell.unicopia.vortex.lore": "Creates a magnetic force that pulls in other targets",
   "spell.unicopia.dark_vortex": "Dark Vortex",

src/main/resources/data/unicopia/recipes/spells/arcane_protection.json

@@ -0,0 +1,14 @@
+{
+  "type": "unicopia:spellbook/crafting",
+  "material": { "item": "unicopia:gemstone", "spell": "unicopia:none" },
+  "traits": {
+    "strength": 10, "knowledge": 18
+  },
+  "ingredients": [
+    { "item": "unicopia:gemstone", "spell": "unicopia:shield" }
+  ],
+  "result": {
+    "item": "unicopia:gemstone",
+    "spell": "unicopia:arcane_protection"
+  }
+}