Core/Group: implement automatic party/raid leader change when the leader has been offline for two minutes (#23398)

* Core/Group: implement automatic party/raid leader change when the leader has been offline for two minutes.

* Add #23396 to make testing easier.

* Prioritize assistants in raids.

* Fix dumb mistake and apply suggested change, thanks VincentVanclef and jackpoz!

(cherry picked from commit e906a2fe7d71fc17de9f7ea4778970beb3f9265e)

7 files changed, 90 insertions, 25 deletions

diff --git a/src/server/game/Groups/Group.cpp b/src/server/game/Groups/Group.cpp
index b69beb76ebe..7cbcbecc934 100644
--- a/src/server/game/Groups/Group.cpp
+++ b/src/server/game/Groups/Group.cpp
@@ -62,7 +62,7 @@ Loot* Roll::getLoot()
 Group::Group() : m_leaderGuid(), m_leaderName(""), m_groupFlags(GROUP_FLAG_NONE), m_groupCategory(GROUP_CATEGORY_HOME),
 m_dungeonDifficulty(DIFFICULTY_NORMAL), m_raidDifficulty(DIFFICULTY_NORMAL_RAID), m_legacyRaidDifficulty(DIFFICULTY_10_N),
 m_bgGroup(nullptr), m_bfGroup(nullptr), m_lootMethod(FREE_FOR_ALL), m_lootThreshold(ITEM_QUALITY_UNCOMMON), m_looterGuid(),
-m_masterLooterGuid(), m_subGroupsCounts(nullptr), m_guid(), m_maxEnchantingLevel(0), m_dbStoreId(0),
+m_masterLooterGuid(), m_subGroupsCounts(nullptr), m_guid(), m_maxEnchantingLevel(0), m_dbStoreId(0), m_isLeaderOffline(false),
 m_readyCheckStarted(false), m_readyCheckTimer(Milliseconds::zero()), m_activeMarkers(0)
 {
     for (uint8 i = 0; i < TARGET_ICONS_COUNT; ++i)
@@ -102,6 +102,57 @@ Group::~Group()
     delete[] m_subGroupsCounts;
 }
 
+void Group::Update(uint32 diff)
+{
+    if (m_isLeaderOffline)
+    {
+        m_leaderOfflineTimer.Update(diff);
+        if (m_leaderOfflineTimer.Passed())
+        {
+            SelectNewPartyOrRaidLeader();
+            m_isLeaderOffline = false;
+        }
+    }
+
+    UpdateReadyCheck(diff);
+}
+
+void Group::SelectNewPartyOrRaidLeader()
+{
+    Player* newLeader = nullptr;
+
+    // Attempt to give leadership to main assistant first
+    if (isRaidGroup())
+    {
+        for (Group::MemberSlot const& memberSlot : m_memberSlots)
+        {
+            if ((memberSlot.flags & MEMBER_FLAG_ASSISTANT) == MEMBER_FLAG_ASSISTANT)
+                if (Player* player = ObjectAccessor::FindPlayer(memberSlot.guid))
+                {
+                    newLeader = player;
+                    break;
+                }
+        }
+    }
+
+    // If there aren't assistants in raid, or if the group is not a raid, pick the first available member
+    if (!newLeader)
+    {
+        for (Group::MemberSlot const& memberSlot : m_memberSlots)
+            if (Player* player = ObjectAccessor::FindPlayer(memberSlot.guid))
+            {
+                newLeader = player;
+                break;
+            }
+    }
+
+    if (newLeader)
+    {
+        ChangeLeader(newLeader->GetGUID());
+        SendUpdate();
+    }
+}
+
 bool Group::Create(Player* leader)
 {
     ObjectGuid leaderGuid = leader->GetGUID();
@@ -2265,11 +2316,6 @@ uint8 Group::GetLfgRoles(ObjectGuid guid)
     return slot->roles;
 }
 
-void Group::Update(uint32 diff)
-{
-    UpdateReadyCheck(diff);
-}
-
 void Group::UpdateReadyCheck(uint32 diff)
 {
     if (!m_readyCheckStarted)
@@ -2681,6 +2727,17 @@ void Group::ToggleGroupMemberFlag(member_witerator slot, uint8 flag, bool apply)
         slot->flags &= ~flag;
 }
 
+void Group::StartLeaderOfflineTimer()
+{
+    m_isLeaderOffline = true;
+    m_leaderOfflineTimer.Reset(2 * MINUTE * IN_MILLISECONDS);
+}
+
+void Group::StopLeaderOfflineTimer()
+{
+    m_isLeaderOffline = false;
+}
+
 void Group::SetEveryoneIsAssistant(bool apply)
 {
     if (apply)
diff --git a/src/server/game/Groups/Group.h b/src/server/game/Groups/Group.h
index 734931b4646..e8aac473ca9 100644
--- a/src/server/game/Groups/Group.h
+++ b/src/server/game/Groups/Group.h
@@ -24,6 +24,7 @@
 #include "Loot.h"
 #include "Object.h"
 #include "SharedDefines.h"
+#include "Timer.h"
 #include <map>
 
 class Battlefield;
@@ -243,6 +244,8 @@ class TC_GAME_API Group
         Group();
         ~Group();
 
+        void Update(uint32 diff);
+
         // group manipulation methods
         bool   Create(Player* leader);
         void   LoadGroupFromDB(Field* field);
@@ -266,7 +269,6 @@ class TC_GAME_API Group
         void   SetEveryoneIsAssistant(bool apply);
 
         // Update
-        void   Update(uint32 diff);
         void   UpdateReadyCheck(uint32 diff);
 
         // Ready check
@@ -414,6 +416,10 @@ class TC_GAME_API Group
         BoundInstancesMap::iterator GetBoundInstances(Difficulty difficulty);
         BoundInstancesMap::iterator GetBoundInstanceEnd();
 
+        void StartLeaderOfflineTimer();
+        void StopLeaderOfflineTimer();
+        void SelectNewPartyOrRaidLeader();
+
         // FG: evil hacks
         void BroadcastGroupUpdate(void);
 
@@ -451,6 +457,8 @@ class TC_GAME_API Group
         ObjectGuid          m_guid;
         uint32              m_maxEnchantingLevel;
         uint32              m_dbStoreId;                    // Represents the ID used in database (Can be reused by other groups if group was disbanded)
+        bool                m_isLeaderOffline;
+        TimeTrackerSmall    m_leaderOfflineTimer;
 
         // Ready Check
         bool                m_readyCheckStarted;
diff --git a/src/server/game/Groups/GroupMgr.cpp b/src/server/game/Groups/GroupMgr.cpp
index b884890c0ba..8d58eb07a86 100644
--- a/src/server/game/Groups/GroupMgr.cpp
+++ b/src/server/game/Groups/GroupMgr.cpp
@@ -109,6 +109,12 @@ Group* GroupMgr::GetGroupByGUID(ObjectGuid const& groupId) const
     return nullptr;
 }
 
+void GroupMgr::Update(uint32 diff)
+{
+    for (std::pair<ObjectGuid::LowType const, Group*> const& group : GroupStore)
+        group.second->Update(diff);
+}
+
 void GroupMgr::AddGroup(Group* group)
 {
     GroupStore[group->GetGUID().GetCounter()] = group;
@@ -244,10 +250,3 @@ void GroupMgr::LoadGroups()
         TC_LOG_INFO("server.loading", ">> Loaded %u group-instance saves in %u ms", count, GetMSTimeDiffToNow(oldMSTime));
     }
 }
-
-void GroupMgr::Update(uint32 diff)
-{
-    for (GroupContainer::iterator itr = GroupStore.begin(); itr != GroupStore.end(); itr++)
-        if (itr->second)
-            itr->second->Update(diff);
-}
diff --git a/src/server/game/Groups/GroupMgr.h b/src/server/game/Groups/GroupMgr.h
index 5d95b291291..781264b78f7 100644
--- a/src/server/game/Groups/GroupMgr.h
+++ b/src/server/game/Groups/GroupMgr.h
@@ -41,14 +41,13 @@ public:
     Group* GetGroupByDbStoreId(uint32 storageId) const;
     void   SetGroupDbStoreSize(uint32 newSize) { GroupDbStore.resize(newSize); }
 
+    void Update(uint32 diff);
+
     void   LoadGroups();
     ObjectGuid::LowType GenerateGroupId();
     void   AddGroup(Group* group);
     void   RemoveGroup(Group* group);
 
-    void   Update(uint32 diff);
-
-
 protected:
     ObjectGuid::LowType           NextGroupId;
     uint32           NextGroupDbStoreId;
diff --git a/src/server/game/Handlers/CharacterHandler.cpp b/src/server/game/Handlers/CharacterHandler.cpp
index 7006ff0d2cc..16aa7a09625 100644
--- a/src/server/game/Handlers/CharacterHandler.cpp
+++ b/src/server/game/Handlers/CharacterHandler.cpp
@@ -1189,6 +1189,8 @@ void WorldSession::HandlePlayerLogin(LoginQueryHolder* holder)
         //pCurrChar->groupInfo.group->SendInit(this); // useless
         group->SendUpdate();
         group->ResetMaxEnchantingLevel();
+        if (group->GetLeaderGUID() == pCurrChar->GetGUID())
+            group->StopLeaderOfflineTimer();
     }
 
     // friend status
diff --git a/src/server/game/Server/WorldSession.cpp b/src/server/game/Server/WorldSession.cpp
index a1416d18410..3c5206e6c27 100644
--- a/src/server/game/Server/WorldSession.cpp
+++ b/src/server/game/Server/WorldSession.cpp
@@ -607,16 +607,13 @@ void WorldSession::LogoutPlayer(bool save)
         ///- If the player is in a group (or invited), remove him. If the group if then only 1 person, disband the group.
         _player->UninviteFromGroup();
 
-        // remove player from the group if he is:
-        // a) in group; b) not in raid group; c) logging out normally (not being kicked or disconnected)
-        if (_player->GetGroup() && !_player->GetGroup()->isRaidGroup() && m_Socket[CONNECTION_TYPE_REALM])
-            _player->RemoveFromGroup();
-
         //! Send update to group and reset stored max enchanting level
-        if (_player->GetGroup())
+        if (Group* group = _player->GetGroup())
         {
-            _player->GetGroup()->SendUpdate();
-            _player->GetGroup()->ResetMaxEnchantingLevel();
+            group->SendUpdate();
+            group->ResetMaxEnchantingLevel();
+            if (group->GetLeaderGUID() == _player->GetGUID())
+                group->StartLeaderOfflineTimer();
         }
 
         //! Broadcast a logout message to the player's friends
diff --git a/src/server/game/World/World.cpp b/src/server/game/World/World.cpp
index 2756ca2afc4..2e83c4365a7 100644
--- a/src/server/game/World/World.cpp
+++ b/src/server/game/World/World.cpp
@@ -2633,6 +2633,9 @@ void World::Update(uint32 diff)
         Player::DeleteOldCharacters();
     }
 
+    sGroupMgr->Update(diff);
+    sWorldUpdateTime.RecordUpdateTimeDuration("UpdateGroupMgr");
+
     sLFGMgr->Update(diff);
     sWorldUpdateTime.RecordUpdateTimeDuration("UpdateLFGMgr");