Refactor leaderboard logic: incorporate room context into leaderboard stats and channel metadata handling

DorkNet.Server/Data/DorkNetDbContext.cs

@@ -497,11 +497,12 @@ public class DorkNetDbContext(DbContextOptions<DorkNetDbContext> options) : DbCo
         modelBuilder.Entity<LeaderboardStatEntity>(e =>
         {
             e.HasKey(s => s.Id);
-            // One row per (player, channel) — enforced unique so
+            // One row per (room, player, channel) — enforced unique so
             // SetStats can upsert without race conditions.
-            e.HasIndex(s => new { s.PlayerId, s.StatChannel }).IsUnique();
-            // Rank computation: ORDER BY Value DESC over a channel.
-            e.HasIndex(s => new { s.StatChannel, s.Value });
+            e.HasIndex(s => new { s.RoomId, s.PlayerId, s.StatChannel }).IsUnique();
+            // Rank computation: ORDER BY Value over a room/channel
+            // (direction is chosen by leaderboard metadata).
+            e.HasIndex(s => new { s.RoomId, s.StatChannel, s.Value });
         });
 
         modelBuilder.Entity<PlayerEloEntity>(e =>
@@ -672,11 +673,9 @@ public class DorkNetDbContext(DbContextOptions<DorkNetDbContext> options) : DbCo
 
         modelBuilder.Entity<LeaderboardChannelMetaEntity>(e =>
         {
-            // Channel int IS the primary key — there's only one
-            // metadata row per stat-channel id, and the channel id
-            // is what the watch reports on POST /SetStats.
-            e.HasKey(c => c.Channel);
-            e.Property(c => c.Channel).ValueGeneratedNever();
+            // Channel ids are reused between rooms; a leaderboard is
+            // identified by (RoomId, Channel), not the channel alone.
+            e.HasKey(c => new { c.RoomId, c.Channel });
             e.HasIndex(c => c.RoomId);
         });
     }

DorkNet.Server/Data/Entities/LeaderboardChannelMetaEntity.cs

@@ -1,7 +1,8 @@
 namespace DorkNet.Server.Data.Entities;
 
 /// <summary>
-/// Admin-curated metadata for a leaderboard <c>StatChannel</c> id. The
+/// Admin-curated metadata for a room-scoped leaderboard
+/// <c>StatChannel</c> id. The
 /// 2020 watch reports raw integer channel ids via
 /// <c>POST api/Leaderboard/v1/SetStats</c>; this table lets admins map
 /// each channel to a specific room (so the room detail page can list
@@ -9,22 +10,19 @@ namespace DorkNet.Server.Data.Entities;
 /// here override the hardcoded <c>AdminController.KnownStatChannels</c>
 /// fallback. Channels with no row stay listed as "Channel N".
 ///
-/// One channel id, one row. Repeated <c>SetStats</c> calls for the same
-/// channel from any room write to that channel's value rows; the meta
-/// row only changes when an admin renames or re-maps it.
+/// One row per (room, channel). Repeated <c>SetStats</c> calls for the
+/// same channel in different rooms do not share metadata or values.
 /// </summary>
 public class LeaderboardChannelMetaEntity
 {
-    /// <summary>Same int the watch reports for this channel. Primary
-    /// key — there's only ever one meta row per channel.</summary>
-    public int Channel { get; set; }
-
     /// <summary>Room this channel "belongs to" for the per-room detail
-    /// view. 0 = global / unscoped (e.g. cross-room player progression
-    /// counters). The same room can own many channels (e.g. Stunt
-    /// Runner has one channel per course).</summary>
+    /// view. 0 = global / unscoped legacy bucket.</summary>
     public long RoomId { get; set; }
 
+    /// <summary>Same int the watch reports for this channel. Only unique
+    /// together with <see cref="RoomId"/>.</summary>
+    public int Channel { get; set; }
+
     public string Name { get; set; } = string.Empty;
 
     /// <summary>When true, a lower stored value is a better score (race

DorkNet.Server/Data/Entities/StatsEntities.cs

@@ -3,7 +3,7 @@ using System.ComponentModel.DataAnnotations;
 namespace DorkNet.Server.Data.Entities;
 
 /// <summary>
-/// One leaderboard stat row per (player, statChannel). Backs
+/// One leaderboard stat row per (room, player, statChannel). Backs
 /// <c>api/Leaderboard/v1/SetStats</c> + <c>api/Leaderboard/v2/getPlayerRank</c>.
 ///
 /// The 2020 watch's <c>RecNet.Leaderboards</c> uses an int channel
@@ -17,6 +17,11 @@ public class LeaderboardStatEntity
     public long Id { get; set; }
     public long PlayerId { get; set; }
 
+    /// <summary>Room the score was reported from. The same stat channel
+    /// id is reused by different rooms, so room scope is part of the
+    /// leaderboard identity. 0 means legacy/global/unscoped.</summary>
+    public long RoomId { get; set; }
+
     /// <summary>RecNet stat channel id (small int per game mode +
     /// stat type — e.g. paintball-CTF-wins, dodgeball-hits).</summary>
     public int StatChannel { get; set; }