Core/Creatures: added sparring system for creatures

src/server/game/Entities/Unit/Unit.cpp

@@ -675,6 +675,17 @@ void Unit::DealDamageMods(Unit const* victim, uint32 &damage, uint32* absorb) co
 
 uint32 Unit::DealDamage(Unit* victim, uint32 damage, CleanDamage const* cleanDamage, DamageEffectType damagetype, SpellSchoolMask damageSchoolMask, SpellInfo const* spellProto, bool durabilityLoss)
 {
+    // Sparring Checks
+    if (Creature* me = ToCreature())
+        if (Creature* target = victim->ToCreature())
+            if (me->CanSparrWith(target))
+            {
+                if (damage >= victim->GetHealth()) // safety check to prevent creatures getting accidentally killed when the percentage is small
+                    damage = victim->GetHealth() - 1;
+                else if (target->GetHealthPct() <= me->GetSparringHealthLimitPctFor(target))
+                    damage = 0;
+            }
+
     if (victim->IsAIEnabled)
         victim->GetAI()->DamageTaken(this, damage);
 
@@ -1871,6 +1882,13 @@ void Unit::CalcAbsorbResist(DamageInfo& damageInfo)
             uint32 split_absorb = 0;
             DealDamageMods(caster, splitDamage, &split_absorb);
 
+            // Sparring Checks
+            if (Creature* me = caster->ToCreature())
+                if (Creature* target = damageInfo.GetVictim()->ToCreature())
+                    if (me->CanSparrWith(target))
+                        if (target->GetHealthPct() <= me->GetSparringHealthLimitPctFor(target))
+                            damageInfo.ModifyDamage(damageInfo.GetDamage() * -1);
+
             SendSpellNonMeleeDamageLog(caster, (*itr)->GetSpellInfo()->Id, splitDamage, damageInfo.GetSchoolMask(), split_absorb, 0, false, 0, false);
 
             CleanDamage cleanDamage = CleanDamage(splitDamage, 0, BASE_ATTACK, MELEE_HIT_NORMAL);
@@ -1977,6 +1995,14 @@ void Unit::AttackerStateUpdate(Unit* victim, WeaponAttackType attType, bool extr
         CalculateMeleeDamage(victim, 0, &damageInfo, attType);
         // Send log damage message to client
         DealDamageMods(victim, damageInfo.damage, &damageInfo.absorb);
+
+        // Sparring Checks
+        if (Creature* me = ToCreature())
+            if (Creature* target = victim->ToCreature())
+                if (me->CanSparrWith(target))
+                    if (target->GetHealthPct() <= me->GetSparringHealthLimitPctFor(target))
+                        damageInfo.HitInfo |= HITINFO_FAKE_DAMAGE;
+
         SendAttackStateUpdate(&damageInfo);
 
         DealMeleeDamage(&damageInfo, true);