[Bleeding] Added Potions API. Fixes BUKKIT-389

By: fullwall <fullwall@optusnet.com>

paper-server/src/main/java/org/bukkit/craftbukkit/potion/CraftPotionBrewer.java

@@ -0,0 +1,47 @@
+package org.bukkit.craftbukkit.potion;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+import net.minecraft.server.MobEffect;
+
+import org.bukkit.potion.PotionEffectType;
+import org.bukkit.potion.PotionBrewer;
+import org.bukkit.potion.PotionEffect;
+
+import com.google.common.collect.Maps;
+
+public class CraftPotionBrewer implements PotionBrewer {
+    private static final Map<Integer, Collection<PotionEffect>> cache = Maps.newHashMap();
+
+    public Collection<PotionEffect> getEffectsFromDamage(int damage) {
+        if (cache.containsKey(damage))
+            return cache.get(damage);
+
+        List<?> mcEffects = net.minecraft.server.PotionBrewer.a(damage, false);
+        List<PotionEffect> effects = new ArrayList<PotionEffect>();
+        if (mcEffects == null)
+            return effects;
+
+        for (Object raw : mcEffects) {
+            if (raw == null || !(raw instanceof MobEffect))
+                continue;
+            MobEffect mcEffect = (MobEffect) raw;
+            PotionEffect effect = new PotionEffect(PotionEffectType.getById(mcEffect.getEffectId()),
+                    mcEffect.getDuration(), mcEffect.getAmplifier());
+            // Minecraft PotionBrewer applies duration modifiers automatically.
+            effects.add(effect);
+        }
+
+        cache.put(damage, effects);
+
+        return effects;
+    }
+
+    public PotionEffect createEffect(PotionEffectType potion, int duration, int amplifier) {
+        return new PotionEffect(potion, potion.isInstant() ? 1 : (int) (duration * potion.getDurationModifier()),
+                amplifier);
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/potion/CraftPotionEffectType.java

@@ -0,0 +1,74 @@
+package org.bukkit.craftbukkit.potion;
+
+import net.minecraft.server.MobEffectList;
+
+import org.bukkit.potion.PotionEffectType;
+
+public class CraftPotionEffectType extends PotionEffectType {
+    private final MobEffectList handle;
+
+    public CraftPotionEffectType(MobEffectList handle) {
+        super(handle.id);
+        this.handle = handle;
+    }
+
+    @Override
+    public double getDurationModifier() {
+        return handle.d();
+    }
+
+    public MobEffectList getHandle() {
+        return handle;
+    }
+
+    @Override
+    public String getName() {
+        switch (handle.id) {
+        case 1:
+            return "SPEED";
+        case 2:
+            return "SLOW";
+        case 3:
+            return "FAST_DIGGING";
+        case 4:
+            return "SLOW_DIGGING";
+        case 5:
+            return "INCREASE_DAMAGE";
+        case 6:
+            return "HEAL";
+        case 7:
+            return "HARM";
+        case 8:
+            return "JUMP";
+        case 9:
+            return "CONFUSION";
+        case 10:
+            return "REGENERATION";
+        case 11:
+            return "DAMAGE_RESISTANCE";
+        case 12:
+            return "FIRE_RESISTANCE";
+        case 13:
+            return "WATER_BREATHING";
+        case 14:
+            return "INVISIBILITY";
+        case 15:
+            return "BLINDNESS";
+        case 16:
+            return "NIGHT_VISION";
+        case 17:
+            return "HUNGER";
+        case 18:
+            return "WEAKNESS";
+        case 19:
+            return "POISON";
+        default:
+            return "UNKNOWN_EFFECT_TYPE_" + handle.id;
+        }
+    }
+
+    @Override
+    public boolean isInstant() {
+        return handle.b();
+    }
+}