Core/Scenarios: Allow scripts to set instance scenario by id (#31104)

* add example at Stratholme service entrance

8 files changed, 58 insertions, 18 deletions

diff --git a/sql/updates/world/master/2025_07_08_00_world.sql b/sql/updates/world/master/2025_07_08_00_world.sql
new file mode 100644
index 00000000000..106e98b1120
--- /dev/null
+++ b/sql/updates/world/master/2025_07_08_00_world.sql
@@ -0,0 +1,3 @@
+DELETE FROM `areatrigger_scripts` WHERE `entry` IN (10107);
+INSERT INTO `areatrigger_scripts` (`entry`, `ScriptName`) VALUES
+(10107, 'at_stratholme_service_entrance');
diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index 41d19ba4e4c..2382850e9f8 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -2809,7 +2809,7 @@ template TC_GAME_API void Map::RemoveFromMap(Conversation*, bool);
 InstanceMap::InstanceMap(uint32 id, time_t expiry, uint32 InstanceId, Difficulty SpawnMode, TeamId InstanceTeam, InstanceLock* instanceLock,
     Optional<uint32> lfgDungeonsId)
   : Map(id, expiry, InstanceId, SpawnMode),
-    i_data(nullptr), i_script_id(0), i_scenario(nullptr), i_instanceLock(instanceLock), i_lfgDungeonsId(lfgDungeonsId)
+    i_data(nullptr), i_script_id(0), i_instanceLock(instanceLock), i_lfgDungeonsId(lfgDungeonsId)
 {
     //lets initialize visibility distance for dungeons
     InstanceMap::InitVisibilityDistance();
@@ -2834,7 +2834,6 @@ InstanceMap::~InstanceMap()
         i_instanceLock->SetInUse(false);
 
     delete i_data;
-    delete i_scenario;
 }
 
 void InstanceMap::InitVisibilityDistance()
@@ -3081,6 +3080,23 @@ std::string const& InstanceMap::GetScriptName() const
     return sObjectMgr->GetScriptName(i_script_id);
 }
 
+void InstanceMap::SetInstanceScenario(InstanceScenario* scenario)
+{
+    i_scenario.reset(); // sends exit packets to all players
+
+    if (scenario)
+    {
+        i_scenario.reset(scenario);
+
+        scenario->LoadInstanceData();
+
+        DoOnPlayers([scenario](Player* player)
+        {
+            scenario->OnPlayerEnter(player);
+        });
+    }
+}
+
 void InstanceMap::UpdateInstanceLock(UpdateBossStateSaveDataEvent const& updateSaveDataEvent)
 {
     if (i_instanceLock)
diff --git a/src/server/game/Maps/Map.h b/src/server/game/Maps/Map.h
index f16d95e5687..af10a1850a8 100644
--- a/src/server/game/Maps/Map.h
+++ b/src/server/game/Maps/Map.h
@@ -904,9 +904,9 @@ class TC_GAME_API InstanceMap : public Map
         std::string const& GetScriptName() const;
         InstanceScript* GetInstanceScript() { return i_data; }
         InstanceScript const* GetInstanceScript() const { return i_data; }
-        InstanceScenario* GetInstanceScenario() { return i_scenario; }
-        InstanceScenario const* GetInstanceScenario() const { return i_scenario; }
-        void SetInstanceScenario(InstanceScenario* scenario) { i_scenario = scenario; }
+        InstanceScenario* GetInstanceScenario() { return i_scenario.get(); }
+        InstanceScenario const* GetInstanceScenario() const { return i_scenario.get(); }
+        void SetInstanceScenario(InstanceScenario* scenario);
         InstanceLock const* GetInstanceLock() const { return i_instanceLock; }
         void UpdateInstanceLock(UpdateBossStateSaveDataEvent const& updateSaveDataEvent);
         void UpdateInstanceLock(UpdateAdditionalSaveDataEvent const& updateSaveDataEvent);
@@ -928,7 +928,7 @@ class TC_GAME_API InstanceMap : public Map
         Optional<SystemTimePoint> i_instanceExpireEvent;
         InstanceScript* i_data;
         uint32 i_script_id;
-        InstanceScenario* i_scenario;
+        std::unique_ptr<InstanceScenario> i_scenario;
         InstanceLock* i_instanceLock;
         GroupInstanceReference i_owningGroupRef;
         Optional<uint32> i_lfgDungeonsId;
diff --git a/src/server/game/Maps/MapManager.cpp b/src/server/game/Maps/MapManager.cpp
index 4332c5a52e2..7d06b19153e 100644
--- a/src/server/game/Maps/MapManager.cpp
+++ b/src/server/game/Maps/MapManager.cpp
@@ -114,7 +114,7 @@ InstanceMap* MapManager::CreateInstance(uint32 mapId, uint32 instanceId, Instanc
         map->TrySetOwningGroup(group);
 
     map->CreateInstanceData();
-    map->SetInstanceScenario(sScenarioMgr->CreateInstanceScenario(map, team));
+    map->SetInstanceScenario(sScenarioMgr->CreateInstanceScenarioForTeam(map, team));
     map->InitSpawnGroupState();
 
     if (sWorld->getBoolConfig(CONFIG_INSTANCEMAP_LOAD_GRIDS))
diff --git a/src/server/game/Scenarios/InstanceScenario.cpp b/src/server/game/Scenarios/InstanceScenario.cpp
index c477cf69fb7..a40a17ecc77 100644
--- a/src/server/game/Scenarios/InstanceScenario.cpp
+++ b/src/server/game/Scenarios/InstanceScenario.cpp
@@ -28,13 +28,6 @@
 
 InstanceScenario::InstanceScenario(InstanceMap* map, ScenarioData const* scenarioData) : Scenario(map, scenarioData)
 {
-    ASSERT(_map);
-    LoadInstanceData();
-
-    Map::PlayerList const& players = map->GetPlayers();
-    for (Map::PlayerList::const_iterator itr = players.begin(); itr != players.end(); ++itr)
-        if (Player* player = itr->GetSource()->ToPlayer())
-            SendScenarioState(player);
 }
 
 void InstanceScenario::LoadInstanceData()
@@ -60,7 +53,7 @@ void InstanceScenario::LoadInstanceData()
                 if (isDespawned)
                     for (auto const& [spawnGroupId, spawn] : sObjectMgr->GetSpawnMetadataForGroup(spawnGroup.SpawnGroupId))
                         if (SpawnData const* spawnData = spawn->ToSpawnData())
-                        ++despawnedCreatureCountsById[spawnData->id];
+                            ++despawnedCreatureCountsById[spawnData->id];
             }
 
             for (Criteria const* criteria : killCreatureCriteria)
diff --git a/src/server/game/Scenarios/ScenarioMgr.cpp b/src/server/game/Scenarios/ScenarioMgr.cpp
index 15bee12f12d..9f4cabbab66 100644
--- a/src/server/game/Scenarios/ScenarioMgr.cpp
+++ b/src/server/game/Scenarios/ScenarioMgr.cpp
@@ -33,7 +33,7 @@ ScenarioMgr* ScenarioMgr::Instance()
     return &instance;
 }
 
-InstanceScenario* ScenarioMgr::CreateInstanceScenario(InstanceMap* map, TeamId team) const
+InstanceScenario* ScenarioMgr::CreateInstanceScenarioForTeam(InstanceMap* map, TeamId team) const
 {
     auto dbDataItr = _scenarioDBData.find(std::make_pair(map->GetId(), map->GetDifficultyID()));
     // No scenario registered for this map and difficulty in the database
@@ -53,10 +53,15 @@ InstanceScenario* ScenarioMgr::CreateInstanceScenario(InstanceMap* map, TeamId t
             break;
     }
 
+    return CreateInstanceScenario(map, scenarioID);
+}
+
+InstanceScenario* ScenarioMgr::CreateInstanceScenario(InstanceMap* map, uint32 scenarioID) const
+{
     auto itr = _scenarioData.find(scenarioID);
     if (itr == _scenarioData.end())
     {
-        TC_LOG_ERROR("scenario", "Table `scenarios` contained data linking scenario (Id: {}) to map (Id: {}), difficulty (Id: {}) but no scenario data was found related to that scenario Id.", scenarioID, map->GetId(), map->GetDifficultyID());
+        TC_LOG_ERROR("scenario", "No scenario data was found related to scenario (Id: {}) for map (Id: {}), difficulty (Id: {}).", scenarioID, map->GetId(), map->GetDifficultyID());
         return nullptr;
     }
 
diff --git a/src/server/game/Scenarios/ScenarioMgr.h b/src/server/game/Scenarios/ScenarioMgr.h
index 96711a998e2..644ad9e4d67 100644
--- a/src/server/game/Scenarios/ScenarioMgr.h
+++ b/src/server/game/Scenarios/ScenarioMgr.h
@@ -110,7 +110,8 @@ public:
 
     static ScenarioMgr* Instance();
 
-    InstanceScenario* CreateInstanceScenario(InstanceMap* map, TeamId team) const;
+    InstanceScenario* CreateInstanceScenarioForTeam(InstanceMap* map, TeamId team) const;
+    InstanceScenario* CreateInstanceScenario(InstanceMap* map, uint32 scenarioID) const;
 
     void LoadDBData();
     void LoadDB2Data();
diff --git a/src/server/scripts/EasternKingdoms/Stratholme/stratholme.cpp b/src/server/scripts/EasternKingdoms/Stratholme/stratholme.cpp
index 0d092af1082..920d2f1d0b2 100644
--- a/src/server/scripts/EasternKingdoms/Stratholme/stratholme.cpp
+++ b/src/server/scripts/EasternKingdoms/Stratholme/stratholme.cpp
@@ -33,7 +33,9 @@ EndContentData */
 #include "GameObject.h"
 #include "GameObjectAI.h"
 #include "Group.h"
+#include "ScenarioMgr.h"
 #include "InstanceScript.h"
+#include "Map.h"
 #include "MotionMaster.h"
 #include "ObjectAccessor.h"
 #include "Player.h"
@@ -388,6 +390,25 @@ class spell_stratholme_haunting_phantoms : public AuraScript
     }
 };
 
+static constexpr uint32 StratholmeLfgDungeonServiceEntrance = 274;
+static constexpr uint32 StratholmeScenarioServiceEntrance = 637;
+
+// 10107 - Areatrigger
+class at_stratholme_service_entrance : public OnlyOnceAreaTriggerScript
+{
+public:
+    at_stratholme_service_entrance() : OnlyOnceAreaTriggerScript("at_stratholme_service_entrance") { }
+
+    bool TryHandleOnce(Player* player, AreaTriggerEntry const* /*areaTrigger*/) override
+    {
+        if (InstanceMap* map = player->GetMap()->ToInstanceMap())
+            if (map->GetLfgDungeonsId() == StratholmeLfgDungeonServiceEntrance)
+                map->SetInstanceScenario(sScenarioMgr->CreateInstanceScenario(map, StratholmeScenarioServiceEntrance));
+
+        return true;
+    }
+};
+
 void AddSC_stratholme()
 {
     new go_gauntlet_gate();
@@ -395,4 +416,5 @@ void AddSC_stratholme()
     new npc_spectral_ghostly_citizen();
     RegisterSpellScript(spell_ysida_saved_credit);
     RegisterSpellScript(spell_stratholme_haunting_phantoms);
+    new at_stratholme_service_entrance();
 }