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!

4 files changed, 78 insertions, 1 deletions

diff --git a/src/server/game/Groups/Group.cpp b/src/server/game/Groups/Group.cpp
index 3a63033575d..74fc5cbdfb7 100644
--- a/src/server/game/Groups/Group.cpp
+++ b/src/server/game/Groups/Group.cpp
@@ -63,7 +63,7 @@ Loot* Roll::getLoot()
 Group::Group() : m_leaderGuid(), m_leaderName(""), m_groupType(GROUPTYPE_NORMAL),
 m_dungeonDifficulty(DUNGEON_DIFFICULTY_NORMAL), m_raidDifficulty(RAID_DIFFICULTY_10MAN_NORMAL),
 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_counter(0), m_maxEnchantingLevel(0), m_dbStoreId(0)
+m_masterLooterGuid(), m_subGroupsCounts(nullptr), m_guid(), m_counter(0), m_maxEnchantingLevel(0), m_dbStoreId(0), m_isLeaderOffline(false)
 {
     for (uint8 i = 0; i < TARGETICONCOUNT; ++i)
         m_targetIcons[i].Clear();
@@ -99,6 +99,55 @@ Group::~Group()
     delete[] m_subGroupsCounts;
 }
 
+void Group::Update(uint32 diff)
+{
+    if (m_isLeaderOffline && (m_groupType == GROUPTYPE_NORMAL || m_groupType == GROUPTYPE_RAID))
+    {
+        m_leaderOfflineTimer.Update(diff);
+        if (m_leaderOfflineTimer.Passed())
+        {
+            SelectNewPartyOrRaidLeader();
+            m_isLeaderOffline = false;
+        }
+    }
+}
+
+void Group::SelectNewPartyOrRaidLeader()
+{
+    Player* newLeader = nullptr;
+
+    // Attempt to give leadership to main assistant first
+    if (m_groupType == GROUPTYPE_RAID)
+    {
+        for (auto 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 (auto 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();
@@ -2554,3 +2603,14 @@ void Group::ToggleGroupMemberFlag(member_witerator slot, uint8 flag, bool apply)
     else
         slot->flags &= ~flag;
 }
+
+void Group::StartLeaderOfflineTimer()
+{
+    m_isLeaderOffline = true;
+    m_leaderOfflineTimer.Reset(2 * MINUTE * IN_MILLISECONDS);
+}
+
+void Group::StopLeaderOfflineTimer()
+{
+    m_isLeaderOffline = false;
+}
diff --git a/src/server/game/Groups/Group.h b/src/server/game/Groups/Group.h
index 842c39cbcda..a7a962f5758 100644
--- a/src/server/game/Groups/Group.h
+++ b/src/server/game/Groups/Group.h
@@ -24,6 +24,7 @@
 #include "GroupRefManager.h"
 #include "Loot.h"
 #include "SharedDefines.h"
+#include "Timer.h"
 #include <map>
 
 class Battlefield;
@@ -184,6 +185,8 @@ class TC_GAME_API Group
         Group();
         ~Group();
 
+        void Update(uint32 diff);
+
         // group manipulation methods
         bool   Create(Player* leader);
         void   LoadGroupFromDB(Field* field);
@@ -327,6 +330,10 @@ class TC_GAME_API Group
         InstanceGroupBind* GetBoundInstance(Difficulty difficulty, uint32 mapId);
         BoundInstancesMap& GetBoundInstances(Difficulty difficulty);
 
+        void StartLeaderOfflineTimer();
+        void StopLeaderOfflineTimer();
+        void SelectNewPartyOrRaidLeader();
+
         // FG: evil hacks
         void BroadcastGroupUpdate(void);
 
@@ -363,5 +370,7 @@ class TC_GAME_API Group
         uint32              m_counter;                      // used only in SMSG_GROUP_LIST
         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;
 };
 #endif
diff --git a/src/server/game/Groups/GroupMgr.cpp b/src/server/game/Groups/GroupMgr.cpp
index 8f2a8917ba6..2d44ee3b955 100644
--- a/src/server/game/Groups/GroupMgr.cpp
+++ b/src/server/game/Groups/GroupMgr.cpp
@@ -109,6 +109,12 @@ Group* GroupMgr::GetGroupByGUID(ObjectGuid::LowType groupId) const
     return nullptr;
 }
 
+void GroupMgr::Update(uint32 diff)
+{
+    for (auto group : GroupStore)
+        group.second->Update(diff);
+}
+
 void GroupMgr::AddGroup(Group* group)
 {
     GroupStore[group->GetLowGUID()] = group;
diff --git a/src/server/game/Groups/GroupMgr.h b/src/server/game/Groups/GroupMgr.h
index b1cb956e8ad..68d176c8038 100644
--- a/src/server/game/Groups/GroupMgr.h
+++ b/src/server/game/Groups/GroupMgr.h
@@ -41,6 +41,8 @@ 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);