purpur-stealth/src/nativeTest/java/games/dmg/spigotstealth/NativePotionDamageTest.java

package games.dmg.spigotstealth;

import static org.junit.jupiter.api.Assertions.*;
import static org.mockito.Mockito.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.UUID;
import net.minecraft.core.RegistryAccess;
import net.minecraft.core.registries.Registries;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.server.level.ServerPlayer;
import net.minecraft.world.damagesource.DamageSource;
import net.minecraft.world.damagesource.DamageSources;
import net.minecraft.world.effect.MobEffectInstance;
import net.minecraft.world.effect.MobEffects;
import net.minecraft.world.entity.LivingEntity;
import org.bukkit.Bukkit;
import org.bukkit.craftbukkit.CraftRegistry;
import org.bukkit.craftbukkit.damage.CraftDamageSource;
import org.bukkit.craftbukkit.entity.CraftPlayer;
import org.bukkit.event.entity.EntityDamageEvent;
import org.bukkit.event.entity.EntityPotionEffectEvent;
import org.bukkit.plugin.PluginManager;
import org.junit.jupiter.api.BeforeAll;

class NativePotionDamageTest {
    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }

    @org.junit.jupiter.params.ParameterizedTest
    @org.junit.jupiter.params.provider.ValueSource(booleans = {false, true})
    @SuppressWarnings("try")
    void actualNativeApplicationAndDamageTickKeepTheObservedPlayerSource(boolean wither) throws Exception {
        var manager = mock(PluginManager.class);
        try (var platform = mockStatic(Bukkit.class, call -> switch (call.getMethod().getName()) {
            case "getPluginManager" -> manager;
            case "isPrimaryThread" -> true;
            default -> call.callRealMethod();
        })) {
            var victim = mock(CraftPlayer.class);
            var attacker = mock(CraftPlayer.class);
            UUID victimId = UUID.randomUUID(), attackerId = UUID.randomUUID();
            when(victim.getUniqueId()).thenReturn(victimId);
            when(attacker.getUniqueId()).thenReturn(attackerId);
            var nativeVictim = mock(ServerPlayer.class);
            var nativeAttacker = mock(ServerPlayer.class);
            when(victim.getHandle()).thenReturn(nativeVictim);
            when(nativeVictim.getBukkitEntity()).thenReturn(victim);
            when(nativeVictim.getBukkitLivingEntity()).thenReturn(victim);
            when(nativeAttacker.getBukkitEntity()).thenReturn(attacker);
            var active = new HashMap<net.minecraft.core.Holder<net.minecraft.world.effect.MobEffect>, MobEffectInstance>();
            var field = LivingEntity.class.getDeclaredField("activeEffects");
            field.setAccessible(true);
            field.set(nativeVictim, active);
            when(nativeVictim.canBeAffected(any(MobEffectInstance.class))).thenReturn(true);
            when(nativeVictim.getEffect(any())).thenAnswer(call -> active.get(call.getArgument(0)));
            when(nativeVictim.addEffect(any(MobEffectInstance.class), any(net.minecraft.world.entity.Entity.class), any(EntityPotionEffectEvent.Cause.class), anyBoolean())).thenCallRealMethod();
            var failures = new ArrayList<Throwable>();
            var attribution = new PotionDamageListener(id -> id.equals(attackerId) ? attacker : null, failures::add);
            var applications = new ArrayList<EntityPotionEffectEvent>();
            doAnswer(call -> {
                if (call.getArgument(0) instanceof EntityPotionEffectEvent event) {
                    applications.add(event);
                    attribution.onEffect(event);
                }
                return null;
            }).when(manager).callEvent(any());
            var type = wither ? MobEffects.WITHER : MobEffects.POISON;
            var potion = new MobEffectInstance(type, wither ? 80 : 100, 0);
            assertTrue(nativeVictim.addEffect(potion, nativeAttacker, EntityPotionEffectEvent.Cause.POTION_SPLASH, true));
            assertSame(attacker, applications.getFirst().getSource());
            assertSame(potion, active.get(type));
            var world = mock(ServerLevel.class);
            var config = mock(org.purpurmc.purpur.PurpurWorldConfig.class);
            config.entityMinimalHealthPoison = 1;
            config.entityPoisonDegenerationAmount = 1;
            config.entityWitherDegenerationAmount = 1;
            var worldConfig = net.minecraft.world.level.Level.class.getField("purpurConfig");
            worldConfig.setAccessible(true);
            worldConfig.set(world, config);
            when(nativeVictim.level()).thenReturn(world);
            when(nativeVictim.getHealth()).thenReturn(10f);
            var sources = new DamageSources(new RegistryAccess.ImmutableRegistryAccess(List.of(CraftRegistry.getMinecraftRegistry(Registries.DAMAGE_TYPE))));
            when(nativeVictim.damageSources()).thenReturn(sources);
            var resolved = new ArrayList<UUID>();
            doAnswer(call -> {
                DamageSource raw = call.getArgument(1);
                assertNull(raw.getEntity(), "native delayed damage does not carry the applying player's identity");
                var event = new EntityDamageEvent(victim, wither ? EntityDamageEvent.DamageCause.WITHER : EntityDamageEvent.DamageCause.POISON,
                        new CraftDamageSource(raw), ((Float) call.getArgument(2)).doubleValue());
                var responsible = attribution.apply(event);
                assertNotNull(responsible, "observed native potion provenance must resolve the responsible player");
                resolved.add(responsible.getUniqueId());
                return true;
            }).when(nativeVictim).hurtServer(eq(world), any(DamageSource.class), anyFloat());
            assertTrue(potion.tickServer(world, nativeVictim, () -> { }));
            assertEquals(List.of(attackerId), resolved);
            attribution.onQuit(new org.bukkit.event.player.PlayerQuitEvent(victim, net.kyori.adventure.text.Component.empty()));
            assertNull(attribution.apply(new EntityDamageEvent(victim, wither ? EntityDamageEvent.DamageCause.WITHER : EntityDamageEvent.DamageCause.POISON,
                    new CraftDamageSource(wither ? sources.wither() : sources.magic()), 1.0)), "disconnect must discard runtime-only victim provenance");
            assertTrue(failures.isEmpty(), failures.toString());
        }
    }
}