refactor(Script/Command): learn spell (#24319)

Co-authored-by: Treeston <14020072+Treeston@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

src/server/game/Entities/Creature/Trainer.cpp

@@ -130,7 +130,7 @@ namespace Trainer
         return nullptr;
     }
 
-    bool Trainer::CanTeachSpell(Player const* player, Spell const* trainerSpell)
+    bool Trainer::CanTeachSpell(Player const* player, Spell const* trainerSpell) const
     {
         SpellState state = GetSpellState(player, trainerSpell);
         if (state != SpellState::Available)

src/server/game/Entities/Creature/Trainer.h

@@ -70,7 +70,7 @@ namespace Trainer
             [[nodiscard]] Spell const* GetSpell(uint32 spellId) const;
             [[nodiscard]] std::vector<Spell> const& GetSpells() const { return _spells; }
             void SendSpells(Creature* npc, Player* player, LocaleConstant locale) const;
-            bool CanTeachSpell(Player const* player, Spell const* trainerSpell);
+            bool CanTeachSpell(Player const* player, Spell const* trainerSpell) const;
             void TeachSpell(Creature* npc, Player* player, uint32 spellId);
 
             [[nodiscard]] Type GetTrainerType() const { return _type; }

src/server/game/Globals/ObjectMgr.cpp

@@ -9719,6 +9719,7 @@ void ObjectMgr::LoadTrainers()
 
     // For reload case
     _trainers.clear();
+    _classTrainers.clear();
 
     std::unordered_map<int32, std::vector<Trainer::Spell>> spellsByTrainer;
     if (QueryResult trainerSpellsResult = WorldDatabase.Query("SELECT TrainerId, SpellId, MoneyCost, ReqSkillLine, ReqSkillRank, ReqAbility1, ReqAbility2, ReqAbility3, ReqLevel FROM trainer_spell"))
@@ -9795,7 +9796,18 @@ void ObjectMgr::LoadTrainers()
                 spellsByTrainer.erase(spellsItr);
             }
 
-            _trainers.emplace(std::piecewise_construct, std::forward_as_tuple(trainerId), std::forward_as_tuple(trainerId, trainerType, requirement, std::move(greeting), std::move(spells)));
+            auto [it, isNew] = _trainers.emplace(std::piecewise_construct, std::forward_as_tuple(trainerId), std::forward_as_tuple(trainerId, trainerType, requirement, std::move(greeting), std::move(spells)));
+            ASSERT(isNew);
+            if (trainerType == Trainer::Type::Class)
+            {
+                if (!requirement || requirement >= MAX_CLASSES)
+                    LOG_ERROR("sql.sql", "Table `trainer` has invalid class requirement for trainer {}, ignoring");
+                else
+                {
+                    uint8 classId = static_cast<uint8>(requirement);
+                    _classTrainers[classId].push_back(&it->second);
+                }
+            }
         } while (trainersResult->NextRow());
     }
 

src/server/game/Globals/ObjectMgr.h

@@ -1418,6 +1418,7 @@ public:
     bool DeleteGameTele(std::string_view name);
 
     Trainer::Trainer* GetTrainer(uint32 creatureId);
+    std::vector<Trainer::Trainer const*> const& GetClassTrainers(uint8 classId) const { return _classTrainers.at(classId); }
 
     [[nodiscard]] VendorItemData const* GetNpcVendorItemList(uint32 entry) const
     {
@@ -1666,6 +1667,7 @@ private:
 
     CacheVendorItemContainer _cacheVendorItemStore;
     std::unordered_map<uint32, Trainer::Trainer> _trainers;
+    std::unordered_map<uint8, std::vector<Trainer::Trainer const*>> _classTrainers;
     std::unordered_map<uint32, uint32> _creatureDefaultTrainers;
 
     std::set<uint32> _difficultyEntries[MAX_DIFFICULTY - 1]; // already loaded difficulty 1 value in creatures, used in CheckCreatureTemplate