From 0f9be64904734c217792002c1b2636ff42aec0ea Mon Sep 17 00:00:00 2001
From: Alexei Kotov <alexdobrohotov@yandex.ru>
Date: Tue, 4 Feb 2025 09:17:31 +0300
Subject: [PATCH] Use the final effect cost to calculate enchantment price
 (#8340)

---
 apps/openmw/mwmechanics/enchanting.cpp | 27 ++++++++++++++++++++------
 apps/openmw/mwmechanics/enchanting.hpp |  2 ++
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/apps/openmw/mwmechanics/enchanting.cpp b/apps/openmw/mwmechanics/enchanting.cpp
index 7d0007f9e3..66bef89e2c 100644
--- a/apps/openmw/mwmechanics/enchanting.cpp
+++ b/apps/openmw/mwmechanics/enchanting.cpp
@@ -185,18 +185,18 @@ namespace MWMechanics
      *
      *  Formula on UESPWiki is not entirely correct.
      */
-    float Enchanting::getEnchantPoints(bool precise) const
+    std::vector<float> Enchanting::getEffectCosts() const
     {
+        std::vector<float> costs;
         if (mEffectList.mList.empty())
-            // No effects added, cost = 0
-            return 0;
+            return costs;
 
+        costs.reserve(mEffectList.mList.size());
         const MWWorld::ESMStore& store = *MWBase::Environment::get().getESMStore();
         const float fEffectCostMult = store.get<ESM::GameSetting>().find("fEffectCostMult")->mValue.getFloat();
         const float fEnchantmentConstantDurationMult
             = store.get<ESM::GameSetting>().find("fEnchantmentConstantDurationMult")->mValue.getFloat();
 
-        float enchantmentCost = 0.f;
         float cost = 0.f;
         for (const ESM::IndexedENAMstruct& effect : mEffectList.mList)
         {
@@ -215,9 +215,18 @@ namespace MWMechanics
             if (effect.mData.mRange == ESM::RT_Target)
                 cost *= 1.5f;
 
-            enchantmentCost += precise ? cost : std::floor(cost);
+            costs.push_back(cost);
         }
 
+        return costs;
+    }
+
+    float Enchanting::getEnchantPoints(bool precise) const
+    {
+        float enchantmentCost = 0.f;
+        for (float cost : getEffectCosts())
+            enchantmentCost += precise ? cost : std::floor(cost);
+
         return enchantmentCost;
     }
 
@@ -278,13 +287,19 @@ namespace MWMechanics
         if (mEnchanter.isEmpty())
             return 0;
 
+        // Use the final effect's accumulated cost
+        float finalEffectCost = 0.f;
+        std::vector<float> effectCosts = getEffectCosts();
+        if (!effectCosts.empty())
+            finalEffectCost = effectCosts.back();
+
         float priceMultipler = MWBase::Environment::get()
                                    .getESMStore()
                                    ->get<ESM::GameSetting>()
                                    .find("fEnchantmentValueMult")
                                    ->mValue.getFloat();
         int price = MWBase::Environment::get().getMechanicsManager()->getBarterOffer(
-            mEnchanter, static_cast<int>(getEnchantPoints() * priceMultipler), true);
+            mEnchanter, static_cast<int>(finalEffectCost * priceMultipler), true);
         price *= count * getTypeMultiplier();
         return std::max(1, price);
     }
diff --git a/apps/openmw/mwmechanics/enchanting.hpp b/apps/openmw/mwmechanics/enchanting.hpp
index 5db02b8cba..98e0982f7c 100644
--- a/apps/openmw/mwmechanics/enchanting.hpp
+++ b/apps/openmw/mwmechanics/enchanting.hpp
@@ -2,6 +2,7 @@
 #define GAME_MWMECHANICS_ENCHANTING_H
 
 #include <string>
+#include <vector>
 
 #include <components/esm3/effectlist.hpp>
 #include <components/esm3/loadench.hpp>
@@ -32,6 +33,7 @@ namespace MWMechanics
         float getTypeMultiplier() const;
         void payForEnchantment(int count) const;
         int getEnchantPrice(int count) const;
+        std::vector<float> getEffectCosts() const;
 
     public:
         Enchanting();