Core/Spells: Fix potions cooldown in combat

Fix a cooldown issue related to potions allowing Players in combat to use more than 1 potion in a row, especially with high latency.
This also fixes an exploit about using infinite potions in combat just by skipping the client-side check.
The original implementation c064c2e2e1eebd43b273365583dd181293bafa22 was missing a check in Spell::CheckCast() about this particular case since Potion cooldown is added only after the Player goes out of combat.
Fixes #1259 .

2 files changed, 5 insertions, 0 deletions

diff --git a/src/server/game/Entities/Player/Player.h b/src/server/game/Entities/Player/Player.h
index 457f5af8361..f04f485fa1e 100644
--- a/src/server/game/Entities/Player/Player.h
+++ b/src/server/game/Entities/Player/Player.h
@@ -1643,6 +1643,7 @@ class Player : public Unit, public GridObject<Player>
         void RemoveAllSpellCooldown();
         void _LoadSpellCooldowns(PreparedQueryResult result);
         void _SaveSpellCooldowns(SQLTransaction& trans);
+        uint32 GetLastPotionId() { return m_lastPotionId; }
         void SetLastPotionId(uint32 item_id) { m_lastPotionId = item_id; }
         void UpdatePotionCooldown(Spell* spell = NULL);
 
diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index 4aedc1a95eb..49eed70f57d 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -4760,6 +4760,10 @@ SpellCastResult Spell::CheckCast(bool strict)
             else
                 return SPELL_FAILED_NOT_READY;
         }
+
+        // check if we are using a potion in combat for the 2nd+ time. Cooldown is added only after caster gets out of combat
+        if (m_caster->ToPlayer()->GetLastPotionId() && m_CastItem && (m_CastItem->IsPotion() || m_spellInfo->IsCooldownStartedOnEvent()))
+            return SPELL_FAILED_NOT_READY;
     }
 
     if (m_spellInfo->AttributesEx7 & SPELL_ATTR7_IS_CHEAT_SPELL && !m_caster->HasFlag(UNIT_FIELD_FLAGS_2, UNIT_FLAG2_ALLOW_CHEAT_SPELLS))