StaticFlags: Implement FOREVER_CORPSE_DURATION (#535)

* StaticFlags: Implement FOREVER_CORPSE_DURATION

* StaticFlags: Guard against CorpseDuration interference

src/game/Entities/Creature.cpp

@@ -1900,7 +1900,10 @@ void Creature::SetDeathState(DeathState s)
         else if (m_respawnOverrideOnce)
             m_respawnOverriden = false;
 
-        m_corpseExpirationTime = GetMap()->GetCurrentClockTime() + std::chrono::milliseconds(m_corpseDelay * IN_MILLISECONDS); // the max/default time for corpse decay (before creature is looted/AllLootRemovedFromCorpse() is called)
+        if (m_settings.HasFlag(CreatureStaticFlags3::FOREVER_CORPSE_DURATION))
+            m_corpseExpirationTime = GetMap()->GetCurrentClockTime() + std::chrono::hours(24*7);
+        else
+            m_corpseExpirationTime = GetMap()->GetCurrentClockTime() + std::chrono::seconds(m_corpseDelay); // the max/default time for corpse decay (before creature is looted/AllLootRemovedFromCorpse() is called)
         m_respawnTime = time(nullptr) + m_respawnDelay; // respawn delay (spawntimesecs)
 
         // always save boss respawn time at death to prevent crash cheating
@@ -2781,6 +2784,8 @@ void Creature::InspectingLoot()
 {
     // until multiple corpse for creature is not supported
     // this will not have effect after re spawn delay (corpse will be removed anyway)
+    if (m_settings.HasFlag(CreatureStaticFlags3::FOREVER_CORPSE_DURATION))
+        return;
 
     // check if player have enough time to inspect loot
     if (m_corpseExpirationTime < GetMap()->GetCurrentClockTime() + std::chrono::milliseconds(m_corpseAccelerationDecayDelay))
@@ -2793,6 +2798,9 @@ void Creature::ReduceCorpseDecayTimer()
     if (!IsInWorld())
         return;
 
+    if (m_settings.HasFlag(CreatureStaticFlags3::FOREVER_CORPSE_DURATION))
+        return;
+
     if (m_corpseExpirationTime > GetMap()->GetCurrentClockTime() + std::chrono::milliseconds(m_corpseAccelerationDecayDelay))
         m_corpseExpirationTime = GetMap()->GetCurrentClockTime() + std::chrono::milliseconds(m_corpseAccelerationDecayDelay);  // 2 minutes for a creature
 }