[Loot] 50% player damage to mob reuired for reward

Unchanged TC backport. Not fully tested.

src/game/Object/Creature.cpp

@@ -150,7 +150,7 @@ Creature::Creature(CreatureSubtype subtype) : Unit(),
     m_AlreadyCallAssistance(false), m_AlreadySearchedAssistance(false),
     m_AI_locked(false), m_IsDeadByDefault(false), m_temporaryFactionFlags(TEMPFACTION_NONE),
     m_meleeDamageSchoolMask(SPELL_SCHOOL_MASK_NORMAL), m_originalEntry(0),
-    m_creatureInfo(NULL)
+    m_creatureInfo(NULL), m_PlayerDamageReq(0)
 {
     /* Loot data */
     hasBeenLootedOnce = false;
@@ -1251,6 +1251,8 @@ void Creature::SelectLevel(const CreatureInfo* cinfo, float percentHealth /*= 10
     else
         { SetHealthPercent(percentHealth); }
 
+    ResetPlayerDamageReq();
+
     SetModifierValue(UNIT_MOD_HEALTH, BASE_VALUE, float(health));
 
     // all power types
@@ -1335,6 +1337,12 @@ float Creature::_GetDamageMod(int32 Rank)
     }
 }
 
+void Creature::LowerPlayerDamageReq(uint32 unDamage)
+{
+    if (m_PlayerDamageReq)
+        m_PlayerDamageReq > unDamage ? m_PlayerDamageReq -= unDamage : m_PlayerDamageReq = 0;
+}
+
 float Creature::_GetSpellDamageMod(int32 Rank)
 {
     switch (Rank)                                           // define rates for each elite rank
@@ -1651,6 +1659,7 @@ void Creature::SetDeathState(DeathState s)
         // Dynamic flags must be set on Tapped by default.
         SetUInt32Value(UNIT_DYNAMIC_FLAGS, UNIT_DYNFLAG_NONE);
         LoadCreatureAddon(true);
+        ResetPlayerDamageReq();
 
         // Flags after LoadCreatureAddon. Any spell in *addon
         // will not be able to adjust these.

src/game/Object/Creature.h

@@ -684,6 +684,9 @@ class Creature : public Unit
         Player* GetLootRecipient() const;                   // use group cases as prefered
         Group* GetGroupLootRecipient() const;
         bool IsTappedBy(Player const* player) const;
+        bool IsDamageEnoughForLootingAndReward() const { return m_PlayerDamageReq == 0; }
+        void LowerPlayerDamageReq(uint32 unDamage);
+        void ResetPlayerDamageReq() { m_PlayerDamageReq = GetHealth() / 2; }
 
         /**
         * function indicating whether the whether the creature has a looter recipient defined (either a group ID, either a player GUID).
@@ -842,6 +845,7 @@ class Creature : public Unit
         MovementGeneratorType m_defaultMovementType;
         Cell m_currentCell;                                 // store current cell where creature listed
         uint32 m_equipmentId;
+        uint32 m_PlayerDamageReq;
 
         // below fields has potential for optimization
         bool m_AlreadyCallAssistance;

src/game/Object/CreatureAI.h

@@ -147,7 +147,7 @@ class CreatureAI
          * Called for reaction at stopping attack at no attackers or targets
          * This is called usually in Unit::SelectHostileTarget, if no more target exists
          */
-        virtual void EnterEvadeMode() {}
+        virtual void EnterEvadeMode() { m_creature->ResetPlayerDamageReq(); }
 
         /**
          * Called at reaching home after MoveTargetedHome

src/game/Object/CreatureEventAI.cpp

@@ -1163,6 +1163,7 @@ void CreatureEventAI::EnterEvadeMode()
         if (i->Event.event_type == EVENT_T_EVADE)
             { ProcessEvent(*i); }
     }
+    m_creature->ResetPlayerDamageReq();
 }
 
 void CreatureEventAI::JustDied(Unit* killer)

src/game/Object/Player.cpp

@@ -14071,8 +14071,8 @@ bool Player::IsTappedByMeOrMyGroup(Creature* creature)
  * Called from Object::BuildValuesUpdate */
 bool Player::isAllowedToLoot(Creature* creature)
 {
-    /* Nobody tapped the monster (solo kill by another NPC) */
-    if (!creature->HasFlag(UNIT_DYNAMIC_FLAGS, UNIT_DYNFLAG_TAPPED))
+    /* Nobody tapped the monster (kill either solo or mostly by another NPC) */
+    if (!creature->HasFlag(UNIT_DYNAMIC_FLAGS, UNIT_DYNFLAG_TAPPED) || !creature->IsDamageEnoughForLootingAndReward())
         { return false; }
 
     /* If we there is a loot recipient, assign it to recipient */

src/game/Object/Unit.cpp

@@ -631,8 +631,14 @@ uint32 Unit::DealDamage(Unit* pVictim, uint32 damage, CleanDamage const* cleanDa
             { SetContestedPvP(attackedPlayer); }
     }
 
-    if (pVictim->GetTypeId() == TYPEID_UNIT && !((Creature*)pVictim)->IsPet() && !((Creature*)pVictim)->HasLootRecipient())
-        { ((Creature*)pVictim)->SetLootRecipient(this); }
+    if (Creature* victim = pVictim->ToCreature())
+    {
+        if (!victim->IsPet() && !victim->HasLootRecipient())
+            victim->SetLootRecipient(this);
+
+        if (IsControlledByPlayer()) // more narrow: IsPet(), IsGuardian() ?
+            victim->LowerPlayerDamageReq(health < damage ? health : damage);
+    }
 
     if (health <= damage)
     {
@@ -681,23 +687,36 @@ uint32 Unit::DealDamage(Unit* pVictim, uint32 damage, CleanDamage const* cleanDa
         /*
          *                      Generic Actions (ProcEvents, Combat-Log, Kill Rewards, Stop Combat)
          */
+        bool isRewardAllowed = true;
+        if (Creature* creature = pVictim->ToCreature())
+        {
+            isRewardAllowed = creature->IsDamageEnoughForLootingAndReward();
+            if (!isRewardAllowed)
+                creature->SetLootRecipient(NULL);
+        }
+
         // call kill spell proc event (before real die and combat stop to triggering auras removed at death/combat stop)
         if (player_tap && player_tap != pVictim)
         {
             player_tap->ProcDamageAndSpell(pVictim, PROC_FLAG_KILL, PROC_FLAG_KILLED, PROC_EX_NONE, 0);
 
-            WorldPacket data(SMSG_PARTYKILLLOG, (8 + 8));   // send event PARTY_KILL
-            data << player_tap->GetObjectGuid();            // player with killing blow
-            data << pVictim->GetObjectGuid();               // victim
+            if (isRewardAllowed)
+            {
+                WorldPacket data(SMSG_PARTYKILLLOG, (8 + 8));   // send event PARTY_KILL
+                data << player_tap->GetObjectGuid();            // player with killing blow
+                data << pVictim->GetObjectGuid();               // victim
 
-            if (group_tap)
-                { group_tap->BroadcastPacket(&data, false, group_tap->GetMemberGroup(player_tap->GetObjectGuid()), player_tap->GetObjectGuid()); }
+                if (group_tap)
+                {
+                    group_tap->BroadcastPacket(&data, false, group_tap->GetMemberGroup(player_tap->GetObjectGuid()), player_tap->GetObjectGuid());
+                }
 
-            player_tap->SendDirectMessage(&data);
+                player_tap->SendDirectMessage(&data);
+            }
         }
 
         // Reward player, his pets, and group/raid members
-        if (player_tap != pVictim)
+        if (isRewardAllowed && player_tap != pVictim)
         {
             if (group_tap)
                 { group_tap->RewardGroupAtKill(pVictim, player_tap); }

src/game/WorldHandlers/Spell.cpp

@@ -962,6 +962,9 @@ void Spell::DoAllEffectOnTarget(TargetInfo* target)
         {
             DoSpellHitOnUnit(m_caster, mask, true);
             unitTarget = m_caster;
+
+            if (m_caster->GetTypeId() == TYPEID_UNIT)
+                m_caster->ToCreature()->LowerPlayerDamageReq(target->damage);
         }
     }
     else                                                    // in 1.12.1 we need explicit miss info