Core/Auras: Implemented helper function to estimate total damage/healing done by a periodic effect

2 files changed, 62 insertions, 16 deletions

diff --git a/src/server/game/Spells/Auras/SpellAuraEffects.cpp b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
index 93276151f8f..73dc1ee087a 100644
--- a/src/server/game/Spells/Auras/SpellAuraEffects.cpp
+++ b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
@@ -711,25 +711,66 @@ int32 AuraEffect::CalculateAmount(Unit* caster)
     if (!GetSpellEffectInfo().EffectAttributes.HasFlag(SpellEffectAttributes::NoScaleWithStack))
         amount *= GetBase()->GetStackAmount();
 
-    if (caster && GetBase()->GetType() == UNIT_AURA_TYPE)
-    {
-        uint32 stackAmountForBonuses = !GetSpellEffectInfo().EffectAttributes.HasFlag(SpellEffectAttributes::NoScaleWithStack) ? GetBase()->GetStackAmount() : 1;
+    _estimatedAmount = CalculateEstimatedAmount(caster, amount);
 
-        switch (GetAuraType())
-        {
-            case SPELL_AURA_PERIODIC_DAMAGE:
-            case SPELL_AURA_PERIODIC_LEECH:
-                _estimatedAmount = caster->SpellDamageBonusDone(GetBase()->GetUnitOwner(), GetSpellInfo(), amount, DOT, GetSpellEffectInfo(), stackAmountForBonuses);
-                break;
-            case SPELL_AURA_PERIODIC_HEAL:
-                _estimatedAmount = caster->SpellHealingBonusDone(GetBase()->GetUnitOwner(), GetSpellInfo(), amount, DOT, GetSpellEffectInfo(), stackAmountForBonuses);
-                break;
-            default:
-                break;
-        }
+    return amount;
+}
+
+Optional<float> AuraEffect::CalculateEstimatedAmount(Unit const* caster, Unit* target, SpellInfo const* spellInfo, SpellEffectInfo const& spellEffectInfo,
+    int32 amount, uint8 stack)
+{
+    uint32 stackAmountForBonuses = !spellEffectInfo.EffectAttributes.HasFlag(SpellEffectAttributes::NoScaleWithStack) ? stack : 1;
+
+    switch (spellEffectInfo.ApplyAuraName)
+    {
+        case SPELL_AURA_PERIODIC_DAMAGE:
+        case SPELL_AURA_PERIODIC_LEECH:
+            return caster->SpellDamageBonusDone(target, spellInfo, amount, DOT, spellEffectInfo, stackAmountForBonuses);
+        case SPELL_AURA_PERIODIC_HEAL:
+            return caster->SpellHealingBonusDone(target, spellInfo, amount, DOT, spellEffectInfo, stackAmountForBonuses);
+        default:
+            break;
     }
 
-    return amount;
+    return {};
+}
+
+Optional<float> AuraEffect::CalculateEstimatedAmount(Unit const* caster, int32 amount) const
+{
+    if (!caster || GetBase()->GetType() != UNIT_AURA_TYPE)
+        return {};
+
+    return CalculateEstimatedAmount(caster, GetBase()->GetUnitOwner(), GetSpellInfo(), GetSpellEffectInfo(), amount, GetBase()->GetStackAmount());
+}
+
+float AuraEffect::CalculateEstimatedfTotalPeriodicAmount(Unit* caster, Unit* target, SpellInfo const* spellInfo, SpellEffectInfo const& spellEffectInfo,
+    float amount, uint8 stack)
+{
+    int32 maxDuration = Aura::CalcMaxDuration(spellInfo, caster);
+    if (maxDuration <= 0)
+        return 0.0f;
+
+    int32 period = spellEffectInfo.ApplyAuraPeriod;
+    if (!period)
+        return 0.0f;
+
+    if (Player* modOwner = caster->GetSpellModOwner())
+        modOwner->ApplySpellMod(spellInfo, SpellModOp::Period, period);
+
+    // Haste modifies periodic time of channeled spells
+    if (spellInfo->IsChanneled())
+        caster->ModSpellDurationTime(spellInfo, period);
+    else if (spellInfo->HasAttribute(SPELL_ATTR5_SPELL_HASTE_AFFECTS_PERIODIC))
+        period = int32(period * caster->m_unitData->ModCastingSpeed);
+
+    if (!period)
+        return 0.0f;
+
+    float totalTicks = float(maxDuration) / period;
+    if (spellInfo->HasAttribute(SPELL_ATTR5_EXTRA_INITIAL_PERIOD))
+        totalTicks += 1.0f;
+
+    return totalTicks * CalculateEstimatedAmount(caster, target, spellInfo, spellEffectInfo, amount, stack).value_or(amount);
 }
 
 uint32 AuraEffect::GetTotalTicks() const
diff --git a/src/server/game/Spells/Auras/SpellAuraEffects.h b/src/server/game/Spells/Auras/SpellAuraEffects.h
index 9342c8956a1..032b8987ebd 100644
--- a/src/server/game/Spells/Auras/SpellAuraEffects.h
+++ b/src/server/game/Spells/Auras/SpellAuraEffects.h
@@ -22,6 +22,7 @@
 
 class AuraEffect;
 class Unit;
+class WorldObject;
 
 typedef void(AuraEffect::*pAuraEffectHandler)(AuraApplication const* aurApp, uint8 mode, bool apply) const;
 
@@ -64,6 +65,9 @@ class TC_GAME_API AuraEffect
         void SetPeriodicTimer(int32 periodicTimer) { _periodicTimer = periodicTimer; }
 
         int32 CalculateAmount(Unit* caster);
+        static Optional<float> CalculateEstimatedAmount(Unit const* caster, Unit* target, SpellInfo const* spellInfo, SpellEffectInfo const& spellEffectInfo, int32 amount, uint8 stack);
+        Optional<float> CalculateEstimatedAmount(Unit const* caster, int32 amount) const;
+        static float CalculateEstimatedfTotalPeriodicAmount(Unit* caster, Unit* target, SpellInfo const* spellInfo, SpellEffectInfo const& spellEffectInfo, float amount, uint8 stack);
         void CalculatePeriodic(Unit* caster, bool resetPeriodicTimer = true, bool load = false);
         void CalculateSpellMod();
         void ChangeAmount(int32 newAmount, bool mark = true, bool onStackOrReapply = false, AuraEffect const* triggeredBy = nullptr);
@@ -83,6 +87,7 @@ class TC_GAME_API AuraEffect
         void ResetPeriodic(bool resetPeriodicTimer = false);
         void ResetTicks() { _ticksDone = 0; }
 
+
         bool IsPeriodic() const { return m_isPeriodic; }
         void SetPeriodic(bool isPeriodic) { m_isPeriodic = isPeriodic; }
         bool IsAffectingSpell(SpellInfo const* spell) const;