Let world handle expedition leader changes

This should eliminate race conditions caused by zones trying to set
a leader when members in different zones quit at the same time

Zone still detects when leader goes offline to trigger a change
since it's easier than having world process expedition member status
updates and perform expedition lookups

world/expedition.cpp

@@ -20,26 +20,83 @@
 
 #include "expedition.h"
 #include "expedition_database.h"
+#include "cliententry.h"
+#include "clientlist.h"
 #include "zonelist.h"
 #include "zoneserver.h"
 #include "../common/eqemu_logsys.h"
 
+extern ClientList client_list;
 extern ZSList zoneserver_list;
 
 Expedition::Expedition(uint32_t expedition_id, uint32_t dz_id, uint32_t dz_instance_id,
-	uint32_t dz_zone_id, uint32_t start_time, uint32_t duration
+	uint32_t dz_zone_id, uint32_t start_time, uint32_t duration, uint32_t leader_id
 ) :
 	m_expedition_id(expedition_id),
 	m_dz_id(dz_id),
 	m_dz_instance_id(dz_instance_id),
 	m_dz_zone_id(dz_zone_id),
 	m_start_time(std::chrono::system_clock::from_time_t(start_time)),
-	m_duration(duration)
+	m_duration(duration),
+	m_leader_id(leader_id)
 {
 	m_expire_time = m_start_time + m_duration;
 	m_warning_cooldown_timer.Enable();
 }
 
+void Expedition::AddMember(uint32_t character_id)
+{
+	auto it = std::find_if(m_member_ids.begin(), m_member_ids.end(),
+		[&](uint32_t member_id) { return member_id == character_id; });
+
+	if (it == m_member_ids.end())
+	{
+		m_member_ids.emplace_back(character_id);
+	}
+}
+
+void Expedition::RemoveMember(uint32_t character_id)
+{
+	m_member_ids.erase(std::remove_if(m_member_ids.begin(), m_member_ids.end(),
+		[&](uint32_t member_id) { return member_id == character_id; }
+	), m_member_ids.end());
+
+	if (!m_member_ids.empty() && character_id == m_leader_id)
+	{
+		ChooseNewLeader();
+	}
+}
+
+void Expedition::ChooseNewLeader()
+{
+	// we don't track expedition member status in world so may choose a linkdead member
+	// this is fine since it will trigger another change when that member goes offline
+	auto it = std::find_if(m_member_ids.begin(), m_member_ids.end(), [&](uint32_t member_id) {
+		auto member_cle = (member_id != m_leader_id) ? client_list.FindCLEByCharacterID(member_id) : nullptr;
+		return (member_id != m_leader_id && member_cle && member_cle->GetOnline() == CLE_Status::InZone);
+	});
+
+	if (it == m_member_ids.end())
+	{
+		// no online members found, fallback to choosing any member
+		it = std::find_if(m_member_ids.begin(), m_member_ids.end(),
+			[&](uint32_t member_id) { return (member_id != m_leader_id); });
+	}
+
+	if (it != m_member_ids.end())
+	{
+		SetNewLeader(*it);
+	}
+}
+
+void Expedition::SetNewLeader(uint32_t character_id)
+{
+	LogExpeditionsModerate("Replacing [{}] leader [{}] with [{}]", m_expedition_id, m_leader_id, character_id);
+	ExpeditionDatabase::UpdateLeaderID(m_expedition_id, character_id);
+	m_leader_id = character_id;
+	SendZonesLeaderChanged();
+}
+
 void Expedition::SendZonesExpeditionDeleted()
 {
 	uint32_t pack_size = sizeof(ServerExpeditionID_Struct);
@@ -69,6 +126,16 @@ void Expedition::SendZonesExpireWarning(uint32_t minutes_remaining)
 	zoneserver_list.SendPacket(pack.get());
 }
 
+void Expedition::SendZonesLeaderChanged()
+{
+	uint32_t pack_size = sizeof(ServerExpeditionLeaderID_Struct);
+	auto pack = std::unique_ptr<ServerPacket>(new ServerPacket(ServerOP_ExpeditionLeaderChanged, pack_size));
+	auto buf = reinterpret_cast<ServerExpeditionLeaderID_Struct*>(pack->pBuffer);
+	buf->expedition_id = GetID();
+	buf->leader_id = m_leader_id;
+	zoneserver_list.SendPacket(pack.get());
+}
+
 void Expedition::UpdateDzSecondsRemaining(uint32_t seconds_remaining)
 {
 	auto now = std::chrono::system_clock::now();

world/expedition.h

@@ -24,19 +24,20 @@
 #include "../common/timer.h"
 #include <chrono>
 #include <cstdint>
-#include <unordered_set>
+#include <vector>
 
 class Expedition
 {
 public:
 	Expedition() = default;
 	Expedition(uint32_t expedition_id, uint32_t dz_id, uint32_t dz_instance_id,
-		uint32_t dz_zone_id, uint32_t expire_time, uint32_t duration);
+		uint32_t dz_zone_id, uint32_t expire_time, uint32_t duration, uint32_t leader_id);
 
-	void AddMember(uint32_t character_id) { m_member_ids.emplace(character_id); }
-	void RemoveMember(uint32_t character_id) { m_member_ids.erase(character_id); }
+	void AddMember(uint32_t character_id);
+	void RemoveMember(uint32_t character_id);
 	void RemoveAllMembers() { m_member_ids.clear(); }
 	void CheckExpireWarning();
+	void ChooseNewLeader();
 	uint32_t GetID() const { return m_expedition_id; }
 	uint16_t GetInstanceID() const { return static_cast<uint16_t>(m_dz_instance_id); }
 	uint16_t GetZoneID() const { return static_cast<uint16_t>(m_dz_zone_id); }
@@ -47,18 +48,22 @@ public:
 	void SendZonesDurationUpdate();
 	void SendZonesExpeditionDeleted();
 	void SendZonesExpireWarning(uint32_t minutes_remaining);
+	void SetNewLeader(uint32_t new_leader_id);
 	void SetPendingDelete(bool pending) { m_pending_delete = pending; }
 	void UpdateDzSecondsRemaining(uint32_t seconds_remaining);
 	std::chrono::system_clock::duration GetRemainingDuration() const;
 
 private:
+	void SendZonesLeaderChanged();
+
 	uint32_t m_expedition_id  = 0;
 	uint32_t m_dz_id          = 0;
 	uint32_t m_dz_instance_id = 0;
 	uint32_t m_dz_zone_id     = 0;
+	uint32_t m_leader_id      = 0;
 	bool     m_pending_delete = false;
 	Timer    m_warning_cooldown_timer;
-	std::unordered_set<uint32_t> m_member_ids;
+	std::vector<uint32_t> m_member_ids;
 	std::chrono::seconds m_duration;
 	std::chrono::time_point<std::chrono::system_clock> m_start_time;
 	std::chrono::time_point<std::chrono::system_clock> m_expire_time;

world/expedition_database.cpp

@@ -77,6 +77,7 @@ std::vector<Expedition> ExpeditionDatabase::LoadExpeditions(uint32_t select_expe
 			instance_list.zone,
 			instance_list.start_time,
 			instance_list.duration,
+			expeditions.leader_id,
 			expedition_members.character_id
 		FROM expeditions
 			INNER JOIN dynamic_zones ON expeditions.dynamic_zone_id = dynamic_zones.id
@@ -110,13 +111,14 @@ std::vector<Expedition> ExpeditionDatabase::LoadExpeditions(uint32_t select_expe
 					static_cast<uint32_t>(strtoul(row[2], nullptr, 10)), // dz_instance_id
 					static_cast<uint32_t>(strtoul(row[3], nullptr, 10)), // dz_zone_id
 					static_cast<uint32_t>(strtoul(row[4], nullptr, 10)), // start_time
-					static_cast<uint32_t>(strtoul(row[5], nullptr, 10))  // duration
+					static_cast<uint32_t>(strtoul(row[5], nullptr, 10)), // duration
+					static_cast<uint32_t>(strtoul(row[6], nullptr, 10))  // leader_id
 				);
 			}
 
 			last_expedition_id = expedition_id;
 
-			uint32_t member_id = static_cast<uint32_t>(strtoul(row[6], nullptr, 10));
+			uint32_t member_id = static_cast<uint32_t>(strtoul(row[7], nullptr, 10));
 			expeditions.back().AddMember(member_id);
 		}
 	}
@@ -167,3 +169,14 @@ void ExpeditionDatabase::UpdateDzDuration(uint16_t instance_id, uint32_t new_dur
 
 	database.QueryDatabase(query);
 }
+
+void ExpeditionDatabase::UpdateLeaderID(uint32_t expedition_id, uint32_t leader_id)
+{
+	LogExpeditionsDetail("Updating leader [{}] for expedition [{}]", leader_id, expedition_id);
+
+	auto query = fmt::format(SQL(
+		UPDATE expeditions SET leader_id = {} WHERE id = {};
+	), leader_id, expedition_id);
+
+	database.QueryDatabase(query);
+}

world/expedition_database.h

@@ -34,6 +34,7 @@ namespace ExpeditionDatabase
 	void PurgeExpiredExpeditions();
 	void PurgeExpiredCharacterLockouts();
 	void UpdateDzDuration(uint16_t instance_id, uint32_t new_duration);
+	void UpdateLeaderID(uint32_t expedition_id, uint32_t leader_id);
 };
 
 #endif

world/expedition_message.cpp

@@ -18,6 +18,7 @@
  *
  */
 
+#include "expedition.h"
 #include "expedition_message.h"
 #include "expedition_state.h"
 #include "cliententry.h"
@@ -34,6 +35,11 @@ void ExpeditionMessage::HandleZoneMessage(ServerPacket* pack)
 {
 	switch (pack->opcode)
 	{
+	case ServerOP_ExpeditionChooseNewLeader:
+	{
+		ExpeditionMessage::ChooseNewLeader(pack);
+		break;
+	}
 	case ServerOP_ExpeditionCreate:
 	{
 		auto buf = reinterpret_cast<ServerExpeditionID_Struct*>(pack->pBuffer);
@@ -51,8 +57,8 @@ void ExpeditionMessage::HandleZoneMessage(ServerPacket* pack)
 	case ServerOP_ExpeditionMemberSwap:
 	{
 		auto buf = reinterpret_cast<ServerExpeditionMemberSwap_Struct*>(pack->pBuffer);
-		expedition_state.MemberChange(buf->expedition_id, buf->remove_char_id, true);
 		expedition_state.MemberChange(buf->expedition_id, buf->add_char_id, false);
+		expedition_state.MemberChange(buf->expedition_id, buf->remove_char_id, true);
 		zoneserver_list.SendPacket(pack);
 		break;
 	}
@@ -141,6 +147,12 @@ void ExpeditionMessage::MakeLeader(ServerPacket* pack)
 		buf->is_char_online = true;
 		new_leader_zs = new_leader_cle->Server();
 		new_leader_zs->SendPacket(pack);
+
+		auto expedition = expedition_state.GetExpedition(buf->expedition_id);
+		if (expedition)
+		{
+			expedition->SetNewLeader(new_leader_cle->CharID());
+		}
 	}
 
 	// if old and new leader are in the same zone only send one message
@@ -205,3 +217,13 @@ void ExpeditionMessage::RequestInvite(ServerPacket* pack)
 		}
 	}
 }
+
+void ExpeditionMessage::ChooseNewLeader(ServerPacket* pack)
+{
+	auto buf = reinterpret_cast<ServerExpeditionID_Struct*>(pack->pBuffer);
+	auto expedition = expedition_state.GetExpedition(buf->expedition_id);
+	if (expedition)
+	{
+		expedition->ChooseNewLeader();
+	}
+}

world/expedition_message.h

@@ -26,6 +26,7 @@ class ServerPacket;
 namespace ExpeditionMessage
 {
 	void AddPlayer(ServerPacket* pack);
+	void ChooseNewLeader(ServerPacket* pack);
 	void GetOnlineMembers(ServerPacket* pack);
 	void HandleZoneMessage(ServerPacket* pack);
 	void MakeLeader(ServerPacket* pack);

world/expedition_state.cpp

@@ -30,6 +30,14 @@ extern ZSList zoneserver_list;
 
 ExpeditionState expedition_state;
 
+Expedition* ExpeditionState::GetExpedition(uint32_t expedition_id)
+{
+	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(),
+		[&](const Expedition& expedition) { return expedition.GetID() == expedition_id; });
+
+	return (it != m_expeditions.end()) ? &(*it) : nullptr;
+}
+
 void ExpeditionState::LoadActiveExpeditions()
 {
 	BenchTimer benchmark;
@@ -51,11 +59,8 @@ void ExpeditionState::AddExpedition(uint32_t expedition_id)
 
 	if (expedition.IsValid())
 	{
-		auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
-			return expedition.GetID() == expedition_id;
-		});
-
-		if (it == m_expeditions.end())
+		auto existing_expedition = GetExpedition(expedition_id);
+		if (!existing_expedition)
 		{
 			m_expeditions.emplace_back(expedition);
 		}
@@ -73,41 +78,32 @@ void ExpeditionState::RemoveExpedition(uint32_t expedition_id)
 
 void ExpeditionState::MemberChange(uint32_t expedition_id, uint32_t character_id, bool remove)
 {
-	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
-		return expedition.GetID() == expedition_id;
-	});
-
-	if (it != m_expeditions.end())
+	auto expedition = GetExpedition(expedition_id);
+	if (expedition)
 	{
 		if (remove) {
-			it->RemoveMember(character_id);
+			expedition->RemoveMember(character_id);
 		} else {
-			it->AddMember(character_id);
+			expedition->AddMember(character_id);
 		}
 	}
 }
 
 void ExpeditionState::RemoveAllMembers(uint32_t expedition_id)
 {
-	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
-		return expedition.GetID() == expedition_id;
-	});
-
-	if (it != m_expeditions.end())
+	auto expedition = GetExpedition(expedition_id);
+	if (expedition)
 	{
-		it->RemoveAllMembers();
+		expedition->RemoveAllMembers();
 	}
 }
 
 void ExpeditionState::SetSecondsRemaining(uint32_t expedition_id, uint32_t seconds_remaining)
 {
-	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
-		return expedition.GetID() == expedition_id;
-	});
-
-	if (it != m_expeditions.end())
+	auto expedition = GetExpedition(expedition_id);
+	if (expedition)
 	{
-		it->UpdateDzSecondsRemaining(seconds_remaining);
+		expedition->UpdateDzSecondsRemaining(seconds_remaining);
 	}
 }
 

world/expedition_state.h

@@ -34,6 +34,7 @@ class ExpeditionState
 {
 public:
 	void AddExpedition(uint32_t expedition_id);
+	Expedition* GetExpedition(uint32_t expedition_id);
 	void LoadActiveExpeditions();
 	void MemberChange(uint32_t expedition_id, uint32_t character_id, bool remove);
 	void Process();

world/zoneserver.cpp

@@ -1362,7 +1362,6 @@ void ZoneServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p) {
 		client_list.SendPacket(buf->character_name, pack);
 		break;
 	}
-	case ServerOP_ExpeditionLeaderChanged:
 	case ServerOP_ExpeditionLockout:
 	case ServerOP_ExpeditionLockoutDuration:
 	case ServerOP_ExpeditionLockState:
@@ -1376,6 +1375,7 @@ void ZoneServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p) {
 		zoneserver_list.SendPacket(pack);
 		break;
 	}
+	case ServerOP_ExpeditionChooseNewLeader:
 	case ServerOP_ExpeditionCreate:
 	case ServerOP_ExpeditionGetOnlineMembers:
 	case ServerOP_ExpeditionMemberChange: