Updates the arena rating system to use Matchmaker Rating.

The arena_team_stats sql in this commit sets all ratings to 0.
You start with 0 Team Rating and 1500 Matchmaker Rating.
Personal rating is moved to character_arena_stats, and will not reset when disbanding an arena team.
This new system is based on all the info I could get, but Blizzard didn't leak much info about the new system.
At least this system is really close to the official system.
Any issues found should be reported in an issue.
Huge thanks go to Aokromes for the intensive testing he has done with me.
Also thanks to Parzival for hearing me out and giving his ideas.
Fixes issue #3189

--HG--
branch : trunk

1 files changed, 115 insertions, 39 deletions

diff --git a/src/server/game/Battlegrounds/ArenaTeam.cpp b/src/server/game/Battlegrounds/ArenaTeam.cpp
index e2b2be9390c..0a4a5b7c11c 100644
--- a/src/server/game/Battlegrounds/ArenaTeam.cpp
+++ b/src/server/game/Battlegrounds/ArenaTeam.cpp
@@ -32,6 +32,14 @@ void ArenaTeamMember::ModifyPersonalRating(Player* plr, int32 mod, uint32 slot)
         plr->SetArenaTeamInfoField(slot, ARENA_TEAM_PERSONAL_RATING, personal_rating);
 }
 
+void ArenaTeamMember::ModifyMatchmakerRating(int32 mod, uint32 slot)
+{
+    if (int32(matchmaker_rating) + mod < 0)
+        matchmaker_rating = 0;
+    else
+        matchmaker_rating += mod;
+}
+
 ArenaTeam::ArenaTeam()
 {
     m_TeamId              = 0;
@@ -102,6 +110,8 @@ bool ArenaTeam::AddMember(const uint64& PlayerGuid)
 {
     std::string plName;
     uint8 plClass;
+    uint32 plPRating;
+    uint32 plMMRating;
 
     // arena team is full (can't have more than type * 2 players!)
     if (GetMembersSize() >= GetType() * 2)
@@ -137,6 +147,18 @@ bool ArenaTeam::AddMember(const uint64& PlayerGuid)
         }
     }
 
+    QueryResult_AutoPtr result = CharacterDatabase.PQuery("SELECT personal_rating, matchmaker_rating FROM character_arena_stats WHERE guid='%u' AND slot='%u'", GUID_LOPART(PlayerGuid), GetSlot());
+    if (!result)
+    {
+        plPRating = 0;
+        plMMRating = 1500;
+    }
+    else
+    {
+        plPRating = (*result)[0].GetUInt32();
+        plMMRating = (*result)[1].GetUInt32();
+    }
+
     // remove all player signs from another petitions
     // this will be prevent attempt joining player to many arenateams and corrupt arena team data integrity
     Player::RemovePetitionsAndSigns(PlayerGuid, GetType());
@@ -149,9 +171,10 @@ bool ArenaTeam::AddMember(const uint64& PlayerGuid)
     newmember.games_week        = 0;
     newmember.wins_season       = 0;
     newmember.wins_week         = 0;
-    newmember.personal_rating   = 0;
+    newmember.personal_rating   = plPRating;
+    newmember.matchmaker_rating = plMMRating;
 
-    if (sWorld.getIntConfig(CONFIG_ARENA_START_PERSONAL_RATING) > 0)
+/*    if (sWorld.getIntConfig(CONFIG_ARENA_START_PERSONAL_RATING) > 0)
         newmember.personal_rating = sWorld.getIntConfig(CONFIG_ARENA_START_PERSONAL_RATING);
     else
     {
@@ -160,17 +183,16 @@ bool ArenaTeam::AddMember(const uint64& PlayerGuid)
         else
             if (GetRating() >= 1000)
                 newmember.personal_rating = 1000;
-    }
+    }*/
 
     m_members.push_back(newmember);
 
-    CharacterDatabase.PExecute("INSERT INTO arena_team_member (arenateamid, guid, personal_rating) VALUES ('%u', '%u', '%u')", m_TeamId, GUID_LOPART(newmember.guid), newmember.personal_rating);
+    CharacterDatabase.PExecute("INSERT INTO arena_team_member (arenateamid, guid) VALUES ('%u', '%u')", m_TeamId, GUID_LOPART(newmember.guid));
 
     if (pl)
     {
         pl->SetInArenaTeam(m_TeamId, GetSlot(), GetType());
         pl->SetArenaTeamIdInvited(0);
-        pl->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_PERSONAL_RATING, newmember.personal_rating);
 
         // hide promote/remove buttons
         if (m_CaptainGuid != PlayerGuid)
@@ -233,15 +255,30 @@ bool ArenaTeam::LoadMembersFromDB(QueryResult_AutoPtr arenaTeamMembersResult)
             //we loaded all members for this arena_team already, break cycle
             break;
 
+        uint32 player_guid = fields[1].GetUInt32();
+
+        QueryResult_AutoPtr result = CharacterDatabase.PQuery(
+            "SELECT personal_rating, matchmaker_rating FROM character_arena_stats WHERE guid = '%u' AND slot = '%u'", player_guid, GetSlot());
+
+        uint32 personalrating = 0;
+        uint32 matchmakerrating = 1500;
+
+        if (result)
+        {
+            personalrating = (*result)[0].GetUInt32();
+            matchmakerrating = (*result)[1].GetUInt32();
+        }
+
         ArenaTeamMember newmember;
-        newmember.guid            = MAKE_NEW_GUID(fields[1].GetUInt32(), 0, HIGHGUID_PLAYER);
-        newmember.games_week      = fields[2].GetUInt32();
-        newmember.wins_week       = fields[3].GetUInt32();
-        newmember.games_season    = fields[4].GetUInt32();
-        newmember.wins_season     = fields[5].GetUInt32();
-        newmember.personal_rating = fields[6].GetUInt32();
-        newmember.name            = fields[7].GetCppString();
-        newmember.Class           = fields[8].GetUInt8();
+        newmember.guid              = MAKE_NEW_GUID(player_guid, 0, HIGHGUID_PLAYER);
+        newmember.games_week        = fields[2].GetUInt32();
+        newmember.wins_week         = fields[3].GetUInt32();
+        newmember.games_season      = fields[4].GetUInt32();
+        newmember.wins_season       = fields[5].GetUInt32();
+        newmember.name              = fields[6].GetCppString();
+        newmember.Class             = fields[7].GetUInt8();
+        newmember.personal_rating   = personalrating;
+        newmember.matchmaker_rating = matchmakerrating;
 
         //check if member exists in characters table
         if (newmember.name.empty())
@@ -563,6 +600,22 @@ uint32 ArenaTeam::GetPoints(uint32 MemberRating)
     return (uint32) points;
 }
 
+uint32 ArenaTeam::GetAverageMMR(Group *group) const
+{
+    if (!group) //should never happen
+        return 0;
+    uint32 matchmakerrating = 0;
+    for (MemberList::const_iterator itr = m_members.begin(); itr != m_members.end(); ++itr)
+    {
+        if (group->IsMember(itr->guid))
+            matchmakerrating += itr->matchmaker_rating;
+    }
+
+    matchmakerrating /= GetType();
+
+    return matchmakerrating;
+}
+
 float ArenaTeam::GetChanceAgainst(uint32 own_rating, uint32 enemy_rating)
 {
     // returns the chance to win against a team with the given rating, used in the rating adjustment calculation
@@ -598,9 +651,13 @@ int32 ArenaTeam::WonAgainst(uint32 againstRating)
     // called when the team has won
     // 'chance' calculation - to beat the opponent
     float chance = GetChanceAgainst(m_stats.rating, againstRating);
-    float K = (m_stats.rating < 1000) ? 48.0f : 32.0f;
-    // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)
-    int32 mod = (int32)floor(K* (1.0f - chance));
+    // calculate the rating modification
+    // simulation on how it works. Not much info on how it really works
+    int32 mod;
+    if (m_stats.rating < 1500)
+        mod = (int32)ceil(48.0f * (1.0f - chance) * (1.0f - chance));
+    else
+        mod = (int32)ceil(24.0f * (1.0f - chance));
 
     // modify the team stats accordingly
     FinishGame(mod);
@@ -611,7 +668,7 @@ int32 ArenaTeam::WonAgainst(uint32 againstRating)
     return mod;
 }
 
-int32 ArenaTeam::LostAgainst(uint32 againstRating)
+int32 ArenaTeam::LostAgainst(uint32 againstRating, bool winnerlowrating)
 {
     // called when the team has lost
     //'chance' calculation - to loose to the opponent
@@ -621,9 +678,14 @@ int32 ArenaTeam::LostAgainst(uint32 againstRating)
         FinishGame(0);
         return 0;
     }
+    // calculate the rating lost
+    // there is not much info on the formula, but this is a very good simulation
+    int32 mod;
+    if (winnerlowrating)
+        mod = (int32)floor(48.0f * chance * chance) * -1;
+    else
+        mod = (int32)floor(24.0f * (0.0f - chance));
 
-    float K = 32.0f;
-    int32 mod = (int32)ceil(K * (0.0f - chance));
     // modify the team stats accordingly
     FinishGame(mod);
 
@@ -631,7 +693,7 @@ int32 ArenaTeam::LostAgainst(uint32 againstRating)
     return mod;
 }
 
-void ArenaTeam::MemberLost(Player * plr, uint32 againstRating)
+void ArenaTeam::MemberLost(Player * plr, uint32 againstMatchmakerRating)
 {
     // called for each participant of a match after losing
     for (MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)
@@ -639,11 +701,15 @@ void ArenaTeam::MemberLost(Player * plr, uint32 againstRating)
         if (itr->guid == plr->GetGUID())
         {
             // update personal rating
-            float chance = GetChanceAgainst(itr->personal_rating, againstRating);
-            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;
-            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)
-            int32 mod = (int32)ceil(K * (0.0f - chance));
+            float chance = GetChanceAgainst(itr->personal_rating, m_stats.rating);
+            // calculate the rating modification
+            int32 mod = (int32)floor(24.0f * (0.0f - chance));
             itr->ModifyPersonalRating(plr, mod, GetSlot());
+            // update matchmaker rating
+            chance = GetChanceAgainst(itr->matchmaker_rating, againstMatchmakerRating);
+            // calculate the rating modification
+            mod = (int32)floor(24.0f * (0.0f - chance));
+            itr->ModifyMatchmakerRating(mod, GetSlot());
             // update personal played stats
             itr->games_week +=1;
             itr->games_season +=1;
@@ -655,7 +721,7 @@ void ArenaTeam::MemberLost(Player * plr, uint32 againstRating)
     }
 }
 
-void ArenaTeam::OfflineMemberLost(uint64 guid, uint32 againstRating)
+void ArenaTeam::OfflineMemberLost(uint64 guid, uint32 againstMatchmakerRating)
 {
     // called for offline player after ending rated arena match!
     for (MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)
@@ -663,14 +729,15 @@ void ArenaTeam::OfflineMemberLost(uint64 guid, uint32 againstRating)
         if (itr->guid == guid)
         {
             // update personal rating
-            float chance = GetChanceAgainst(itr->personal_rating, againstRating);
-            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;
-            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)
-            int32 mod = (int32)ceil(K * (0.0f - chance));
-            if (int32(itr->personal_rating) + mod < 0)
-                itr->personal_rating = 0;
-            else
-                itr->personal_rating += mod;
+            float chance = GetChanceAgainst(itr->personal_rating, m_stats.rating);
+            // calculate the rating modification
+            int32 mod = (int32)ceil(24.0f * (0.0f - chance));
+            itr->ModifyPersonalRating(NULL, mod, GetSlot());
+            // update matchmaker rating
+            chance = GetChanceAgainst(itr->matchmaker_rating, againstMatchmakerRating);
+            // calculate the rating modification
+            mod = (int32)ceil(24.0f * (0.0f - chance));
+            itr->ModifyMatchmakerRating(mod, GetSlot());
             // update personal played stats
             itr->games_week +=1;
             itr->games_season +=1;
@@ -679,19 +746,25 @@ void ArenaTeam::OfflineMemberLost(uint64 guid, uint32 againstRating)
     }
 }
 
-void ArenaTeam::MemberWon(Player * plr, uint32 againstRating)
+void ArenaTeam::MemberWon(Player * plr, uint32 againstMatchmakerRating)
 {
     // called for each participant after winning a match
     for (MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)
     {
         if (itr->guid == plr->GetGUID())
         {
+            uint32 matchmakerrating = itr->matchmaker_rating;
             // update personal rating
-            float chance = GetChanceAgainst(itr->personal_rating, againstRating);
-            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;
-            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)
-            int32 mod = (int32)floor(K* (1.0f - chance));
+            float chance = GetChanceAgainst(itr->personal_rating, m_stats.rating);
+            // calculate the rating modification
+            int32 mod = (int32)ceil(24.0f * (1.0f - chance));
             itr->ModifyPersonalRating(plr, mod, GetSlot());
+            // update matchmaker rating
+            chance = GetChanceAgainst(matchmakerrating, againstMatchmakerRating);
+            // calculate the rating modification
+            mod = (int32)ceil(24.0f * (1.0f - chance));
+            itr->ModifyMatchmakerRating(mod, GetSlot());
+
             // update personal stats
             itr->games_week +=1;
             itr->games_season +=1;
@@ -741,7 +814,10 @@ void ArenaTeam::SaveToDB()
     SQLTransaction trans = CharacterDatabase.BeginTransaction();
     trans->PAppend("UPDATE arena_team_stats SET rating = '%u',games = '%u',played = '%u',rank = '%u',wins = '%u',wins2 = '%u' WHERE arenateamid = '%u'", m_stats.rating, m_stats.games_week, m_stats.games_season, m_stats.rank, m_stats.wins_week, m_stats.wins_season, GetId());
     for (MemberList::const_iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)
-        trans->PAppend("UPDATE arena_team_member SET played_week = '%u', wons_week = '%u', played_season = '%u', wons_season = '%u', personal_rating = '%u' WHERE arenateamid = '%u' AND guid = '%u'", itr->games_week, itr->wins_week, itr->games_season, itr->wins_season, itr->personal_rating, m_TeamId, GUID_LOPART(itr->guid));
+    {
+        trans->PAppend("UPDATE arena_team_member SET played_week = '%u', wons_week = '%u', played_season = '%u', wons_season = '%u' WHERE arenateamid = '%u' AND guid = '%u'", itr->games_week, itr->wins_week, itr->games_season, itr->wins_season, m_TeamId, GUID_LOPART(itr->guid));
+        trans->PAppend("REPLACE INTO character_arena_stats (guid,slot,personal_rating,matchmaker_rating) VALUES ('%u', '%u', '%u', '%u')", GUID_LOPART(itr->guid), GetSlot(), itr->personal_rating, itr->matchmaker_rating);
+    }
     CharacterDatabase.CommitTransaction(trans);
 }