Core/Player: fix some PCT_MOD charge consumption

By xinef1

Closes #18516

2 files changed, 22 insertions, 5 deletions

diff --git a/src/server/game/Entities/Player/Player.cpp b/src/server/game/Entities/Player/Player.cpp
index a827ed46edf..32b026da160 100644
--- a/src/server/game/Entities/Player/Player.cpp
+++ b/src/server/game/Entities/Player/Player.cpp
@@ -20901,6 +20901,14 @@ void Player::RestoreAllSpellMods(uint32 ownerAuraId /*= 0*/, Aura* aura /*= null
             RestoreSpellMods(spell, ownerAuraId, aura);
 }
 
+bool Player::HasSpellModApplied(SpellModifier* mod, Spell* spell)
+{
+    if (!spell)
+        return false;
+
+    return spell->m_appliedMods.count(mod->ownerAura) != 0;
+}
+
 void Player::ApplyModToSpell(SpellModifier* mod, Spell* spell)
 {
     if (!spell)
diff --git a/src/server/game/Entities/Player/Player.h b/src/server/game/Entities/Player/Player.h
index dcaa2199496..51bfb112b93 100644
--- a/src/server/game/Entities/Player/Player.h
+++ b/src/server/game/Entities/Player/Player.h
@@ -1610,6 +1610,7 @@ class TC_GAME_API Player : public Unit, public GridObject<Player>
         void RestoreSpellMods(Spell* spell, uint32 ownerAuraId = 0, Aura* aura = nullptr);
         void RestoreAllSpellMods(uint32 ownerAuraId = 0, Aura* aura = nullptr);
         static void ApplyModToSpell(SpellModifier* mod, Spell* spell);
+        static bool HasSpellModApplied(SpellModifier* mod, Spell* spell);
         void SetSpellModTakingSpell(Spell* spell, bool apply);
 
         void RemoveArenaSpellCooldowns(bool removeActivePetCooldowns = false);
@@ -2634,7 +2635,7 @@ void Player::ApplySpellMod(uint32 spellId, T& basevalue, Spell* spell /*= nullpt
         case SPELLMOD_CASTING_TIME:
         {
             SpellModifier* modInstantSpell = nullptr;
-            for (SpellModifier* mod : m_spellMods[SPELLMOD_CASTING_TIME])
+            for (SpellModifier* mod : m_spellMods[op])
             {
                 if (!IsAffectedBySpellmod(spellInfo, mod, spell))
                     continue;
@@ -2658,7 +2659,7 @@ void Player::ApplySpellMod(uint32 spellId, T& basevalue, Spell* spell /*= nullpt
         case SPELLMOD_CRITICAL_CHANCE:
         {
             SpellModifier* modCritical = nullptr;
-            for (SpellModifier* mod : m_spellMods[SPELLMOD_CRITICAL_CHANCE])
+            for (SpellModifier* mod : m_spellMods[op])
             {
                 if (!IsAffectedBySpellmod(spellInfo, mod, spell))
                     continue;
@@ -2694,14 +2695,22 @@ void Player::ApplySpellMod(uint32 spellId, T& basevalue, Spell* spell /*= nullpt
                 break;
             case SPELLMOD_PCT:
             {
-                // skip percent mods for null basevalue (most important for spell mods with charges)
+                // skip percent mods with null basevalue (most important for spell mods with charges)
                 if (basevalue == T(0))
                     continue;
 
                 // special case (skip > 10sec spell casts for instant cast setting)
-                if (op == SPELLMOD_CASTING_TIME)
+                if (op == SPELLMOD_CASTING_TIME && mod->value <= -100 && basevalue >= T(10000))
+                    continue;
+                else if (!Player::HasSpellModApplied(mod, spell))
                 {
-                    if (mod->value <= -100 && basevalue >= T(10000))
+                    // special case for Surge of Light, don't apply critical chance reduction if other mods not applied (ie procs while casting another spell)
+                    // (Surge of Light is the only PCT_MOD on critical chance)
+                    if (op == SPELLMOD_CRITICAL_CHANCE)
+                        continue;
+                    // special case for Backdraft, dont' apply GCD reduction if cast time reduction wasn't applied (ie when Backlash is consumed first)
+                    // (Backdraft is the only PCT_MOD on global cooldown)
+                    else if (op == SPELLMOD_GLOBAL_COOLDOWN)
                         continue;
                 }