Team nerf

ffa-server/src/main/java/gg/norisk/ffa/server/mixin/ServerPlayerEntityMixin.java

@@ -3,6 +3,9 @@
 import com.mojang.authlib.GameProfile;
 import gg.norisk.ffa.server.mechanics.KitEditor;
 import gg.norisk.ffa.server.mechanics.SoupHealing;
+import gg.norisk.ffa.server.mechanics.TeamNerf;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.damage.DamageSource;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.item.Items;
 import net.minecraft.server.network.ServerPlayerEntity;
@@ -13,17 +16,15 @@
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 @Mixin(ServerPlayerEntity.class)
 public abstract class ServerPlayerEntityMixin extends PlayerEntity {
     public ServerPlayerEntityMixin(World world, BlockPos blockPos, float f, GameProfile gameProfile) {
         super(world, blockPos, f, gameProfile);
     }
 
-    @Inject(
-            method = "swingHand",
-            at = @At("HEAD")
-    )
+    @Inject(method = "swingHand", at = @At("HEAD"))
     public void onSwing(Hand hand, CallbackInfo ci) {
         if (!KitEditor.INSTANCE.isUHC()) {
             ServerPlayerEntity player = (ServerPlayerEntity) (Object) this;
@@ -33,4 +34,18 @@ public void onSwing(Hand hand, CallbackInfo ci) {
             }
         }
     }
+
+    @Inject(method = "attack", at = @At("HEAD"))
+    public void onAttack(Entity target, CallbackInfo ci) {
+        if (target instanceof PlayerEntity) {
+            TeamNerf.INSTANCE.onAttack(this, (PlayerEntity) target);
+        }
+    }
+
+    @Inject(method = "getDamageAgainst", at = @At("RETURN"), cancellable = true)
+    public void onGetDamageAgainst(Entity target, float baseDamage, DamageSource damageSource, CallbackInfoReturnable<Float> cir) {
+        if (target instanceof ServerPlayerEntity) {
+            cir.setReturnValue(TeamNerf.INSTANCE.getDamageAgainst((PlayerEntity) target, cir.getReturnValue()));
+        }
+    }
 }

ffa-server/src/main/kotlin/gg/norisk/ffa/server/FFAServer.kt

@@ -9,6 +9,7 @@ import gg.norisk.ffa.server.mechanics.Bounty
 import gg.norisk.ffa.server.mechanics.CombatTag
 import gg.norisk.ffa.server.mechanics.KillManager
 import gg.norisk.ffa.server.mechanics.KitEditor
+import gg.norisk.ffa.server.mechanics.TeamNerf
 import gg.norisk.ffa.server.selector.SelectorServerManager
 import gg.norisk.ffa.server.world.MapPlacer
 import gg.norisk.ffa.server.world.WorldManager
@@ -35,6 +36,7 @@ object FFAServer : ModInitializer {
         CombatTag.init()
         KillManager.init()
         InvseeCommand.init()
+        TeamNerf.init()
     }
 
     const val FFA_KEY = "hero-ffa"

ffa-server/src/main/kotlin/gg/norisk/ffa/server/mechanics/TeamNerf.kt

@@ -0,0 +1,51 @@
+package gg.norisk.ffa.server.mechanics
+
+import net.minecraft.entity.player.PlayerEntity
+import net.silkmc.silk.core.task.mcCoroutineTask
+import kotlin.math.pow
+import kotlin.time.DurationUnit
+import kotlin.time.toDuration
+
+object TeamNerf {
+    val hits: MutableMap<PlayerEntity, MutableMap<PlayerEntity, Long>> = mutableMapOf()
+
+    fun init() {
+        mcCoroutineTask(sync = true, client = false, period = 1.toDuration(DurationUnit.SECONDS)) {
+            hits.forEach {
+                val player = it.key
+                if (!player.isAlive) {
+                    hits.remove(player)
+                    return@forEach
+                }
+                val hitMap = it.value
+                hitMap.forEach { target, time ->
+                    if (!target.isAlive || player.world != target.world || player.distanceTo(target) > 20) {
+                        hitMap.remove(target)
+                    }
+                }
+            }
+        }
+    }
+
+    fun onAttack(player: PlayerEntity, target: PlayerEntity) {
+        if (player == target) {
+            return
+        }
+        if (!hits.contains(player)) {
+            hits[player] = mutableMapOf()
+        }
+        val hits = hits[player]!!
+        hits[target] = System.currentTimeMillis()
+    }
+
+    fun getDamageAgainst(target: PlayerEntity, damage: Float): Float {
+        val hits = hits[target] ?: mapOf()
+        var teamSize = 0
+        for (hit in hits) {
+            if (hit.value + 1000*10 > System.currentTimeMillis()) {
+                teamSize++
+            }
+        }
+        return if (teamSize > 1) damage * teamSize.toFloat().pow(-0.8f) else damage
+    }
+}