refactor(battlenode): rename mode-id field off BattleType, add BattleModes (§D)

Behavior-preserving; 271 BattleNode/Matching/Services tests green, full solution builds.

"BattleType" meant two things: the Sessions.BattleType enum (Pvp/Bot) and an int
"mode id" field. Renamed the int field on MatchContext AND the BattleStartBody wire
DTO to BattleModeId (wire key stays "battleType" via JsonPropertyName), so BattleType
now means only the enum project-wide.

New Bridge/BattleModes.cs (TakeTwo = 11) replaces every 11 literal — both prod
MatchContextBuilder sites and the test fixtures/assertions. The arbitrary-passthrough
42 and bot 0 stay literal.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

SVSim.BattleNode/Bridge/BattleModes.cs

@@ -0,0 +1,14 @@
+namespace SVSim.BattleNode.Bridge;
+
+/// <summary>
+/// Known values for <see cref="MatchContext.BattleModeId"/> — the prod do_matching battle-mode id,
+/// forwarded verbatim onto the wire (<c>battleType</c> field on BattleStart). Names the otherwise
+/// magic <c>11</c>. Distinct from the <see cref="Sessions.BattleType"/> enum (Pvp/Bot), which is the
+/// session topology, not the game mode.
+/// </summary>
+public static class BattleModes
+{
+    /// <summary>Take Two (TK2) — the two-pick draft mode the v1 captures were taken from. Prod
+    /// rank-battle frames carry the same value (see <c>MatchContextBuilder</c>).</summary>
+    public const int TakeTwo = 11;
+}

SVSim.BattleNode/Bridge/MatchContext.cs

@@ -25,5 +25,8 @@ public sealed record MatchContext(
     int    FieldId,
     int    IsOfficial,      // 0 or 1
 
-    // Battle-mode hint, currently TK2 == 11. Future modes populate their own value.
+    // Battle-mode hint (the prod do_matching mode id). Named BattleModeId, NOT BattleType, to
-    int    BattleType);
+    // avoid colliding with the <see cref="Sessions.BattleType"/> enum (Pvp/Bot) — a different axis.
+    // Known values live in <see cref="BattleModes"/> (currently just TK2 == 11). Future modes add
+    // their own constant.
+    int    BattleModeId);

SVSim.BattleNode/Lifecycle/ServerBattleFrames.cs

@@ -55,7 +55,7 @@ public static class ServerBattleFrames
         EnvelopeForPush(NetworkBattleUri.BattleStart,
             new BattleStartBody(
                 TurnState: turnState,    // First = this side goes first, Second = second. Caller decides.
-                BattleType: selfCtx.BattleType,
+                BattleModeId: selfCtx.BattleModeId,
                 SelfInfo: new BattleStartSelfInfo(
                     Rank: BattleFrameDefaults.PlayerRank,
                     BattlePoint: BattleFrameDefaults.PlayerBattlePoint,

SVSim.BattleNode/Protocol/Bodies/BattleStartBody.cs

@@ -5,7 +5,9 @@ namespace SVSim.BattleNode.Protocol.Bodies;
 public sealed record BattleStartBody(
     [property: JsonPropertyName("turnState")]
     [property: JsonConverter(typeof(JsonNumberEnumConverter<TurnState>))] TurnState TurnState,
-    [property: JsonPropertyName("battleType")] int BattleType,
+    // Wire key stays "battleType" (the client's contract); the CLR name is BattleModeId so the
+    // project keeps one meaning of "BattleType" — the Sessions.BattleType enum (Pvp/Bot).
+    [property: JsonPropertyName("battleType")] int BattleModeId,
     [property: JsonPropertyName("selfInfo")] BattleStartSelfInfo SelfInfo,
     [property: JsonPropertyName("oppoInfo")] BattleStartOppoInfo OppoInfo,
     [property: JsonPropertyName("resultCode")] int ResultCode = (int)ReceiveNodeResultCode.Success) : IMsgBody;

SVSim.BattleNode/Sessions/Participants/NoOpBotParticipant.cs

@@ -23,7 +23,7 @@ public sealed class NoOpBotParticipant : IBattleParticipant
         ClassId: "0", CharaId: "0", CardMasterName: BotCardMasterName,
         CountryCode: "", UserName: "Bot", SleeveId: "0",
         EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0,
-        BattleType: 0);
+        BattleModeId: 0);
 
     // Required by IBattleParticipant, but a silent bot never raises it — suppress the
     // "event is never used" warning rather than keeping a dead null-emitting method.

SVSim.EmulatedEntrypoint/Services/MatchContextBuilder.cs

@@ -67,7 +67,7 @@ public class MatchContextBuilder : IMatchContextBuilder
             // Hardcoded v1; needs equipped-MyPageBackground lookup (see spec §Deferred).
             FieldId: 43,
             IsOfficial: viewer.Info.IsOfficial ? 1 : 0,
-            BattleType: 11);
+            BattleModeId: BattleModes.TakeTwo);
     }
 
     public async Task<MatchContext> BuildForRankBattleAsync(long viewerId, Format format, int deckNo)
@@ -114,6 +114,6 @@ public class MatchContextBuilder : IMatchContextBuilder
             DegreeId: degreeId,
             FieldId: 43,
             IsOfficial: viewer.Info.IsOfficial ? 1 : 0,
-            BattleType: 11);
+            BattleModeId: BattleModes.TakeTwo);
     }
 }

SVSim.UnitTests/BattleNode/Bridge/MatchingBridgeTests.cs

@@ -96,5 +96,5 @@ public class MatchingBridgeTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 }

SVSim.UnitTests/BattleNode/Hosting/WaitingRoomTests.cs

@@ -72,7 +72,7 @@ public class WaitingRoomTests
             ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
             CountryCode: "KOR", UserName: "Player", SleeveId: "0",
             EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0,
-            BattleType: 11);
+            BattleModeId: BattleModes.TakeTwo);
         return new RealParticipant(ws, viewerId, ctx, NullLogger<RealParticipant>.Instance);
     }
 }

SVSim.UnitTests/BattleNode/Integration/BattleNodeFlowTests.cs

@@ -26,7 +26,7 @@ public class BattleNodeFlowTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     /// <summary>
     /// End-to-end: a viewer with a real TK2 run sees their drafted card-ids in the Matched

SVSim.UnitTests/BattleNode/Lifecycle/ServerBattleFramesTests.cs

@@ -69,22 +69,22 @@ public class ServerBattleFramesTests
     }
 
     [Test]
-    public void BuildBattleStart_HasTurnStateZero_AndUsesContextBattleType()
+    public void BuildBattleStart_HasTurnStateZero_AndUsesContextBattleModeId()
     {
         var env = ServerBattleFrames.BuildBattleStart(FixtureCtx(), FakeOpponentCtx(), selfViewerId: 1, turnState: TurnState.First);
         var body = (BattleStartBody)env.Body;
         Assert.That(body.TurnState, Is.EqualTo(TurnState.First));
-        Assert.That(body.BattleType, Is.EqualTo(11));
+        Assert.That(body.BattleModeId, Is.EqualTo(BattleModes.TakeTwo));
     }
 
     [Test]
-    public void BuildBattleStart_class_chara_cardMaster_battleType_flow_from_context()
+    public void BuildBattleStart_class_chara_cardMaster_battleModeId_flow_from_context()
     {
         var ctx = FixtureCtx() with
         {
             ClassId = "7", CharaId = "5000123",
             CardMasterName = "card_master_test_v2",
-            BattleType = 42,
+            BattleModeId = 42,
         };
 
         var env = ServerBattleFrames.BuildBattleStart(ctx, FakeOpponentCtx(), selfViewerId: 1, turnState: TurnState.First);
@@ -93,7 +93,7 @@ public class ServerBattleFramesTests
         Assert.That(body.SelfInfo.ClassId, Is.EqualTo("7"));
         Assert.That(body.SelfInfo.CharaId, Is.EqualTo("5000123"));
         Assert.That(body.SelfInfo.CardMasterName, Is.EqualTo("card_master_test_v2"));
-        Assert.That(body.BattleType, Is.EqualTo(42));
+        Assert.That(body.BattleModeId, Is.EqualTo(42));
     }
 
     [Test]
@@ -171,7 +171,7 @@ public class ServerBattleFramesTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     // A prod-captured opponent MatchContext fixture that the BuildMatched/BuildBattleStart
     // helpers read from for the oppo half.
@@ -180,5 +180,5 @@ public class ServerBattleFramesTests
         ClassId: "8", CharaId: "8", CardMasterName: "card_master_node_10015",
         CountryCode: "JPN", UserName: "Opponent", SleeveId: "704141010",
         EmblemId: "400001100", DegreeId: "120027", FieldId: 5, IsOfficial: 0,
-        BattleType: 0);
+        BattleModeId: 0);
 }

SVSim.UnitTests/BattleNode/Lifecycle/TypedBodyWireShapeTests.cs

@@ -158,7 +158,7 @@ public class TypedBodyWireShapeTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     // Prod-captured opponent fixture — 30-card deck and the prod-captured opponent
     // cosmetics (ClassId/CharaId "8") so the wire bytes asserted below (oppoInfo classId/charaId,
@@ -169,5 +169,5 @@ public class TypedBodyWireShapeTests
         ClassId: "8", CharaId: "8", CardMasterName: "card_master_node_10015",
         CountryCode: "JPN", UserName: "Opponent", SleeveId: "704141010",
         EmblemId: "400001100", DegreeId: "120027", FieldId: 5, IsOfficial: 0,
-        BattleType: 0);
+        BattleModeId: 0);
 }

SVSim.UnitTests/BattleNode/Protocol/Bodies/BattleStartBodyTests.cs

@@ -1,6 +1,7 @@
 using System.Text.Json;
 using System.Text.Json.Nodes;
 using NUnit.Framework;
+using SVSim.BattleNode.Bridge;
 using SVSim.BattleNode.Protocol;
 using SVSim.BattleNode.Protocol.Bodies;
 
@@ -13,7 +14,7 @@ public class BattleStartBodyTests
     public void Serializes_TopLevelFields_WithCorrectWireKeys()
     {
         var body = new BattleStartBody(
-            TurnState: TurnState.First, BattleType: 11,
+            TurnState: TurnState.First, BattleModeId: BattleModes.TakeTwo,
             SelfInfo: new BattleStartSelfInfo("10", "6270", "1", "1", "card_master_node_10015"),
             OppoInfo: new BattleStartOppoInfo("1", "0", 0, "0", "8", "8", "card_master_node_10015"));
 

SVSim.UnitTests/BattleNode/Sessions/BattleSessionDispatchConcurrencyTests.cs

@@ -64,13 +64,13 @@ public class BattleSessionDispatchConcurrencyTests
         SelfDeckCardIds: Enumerable.Range(1, 30).Select(_ => 100_011_010L).ToList(),
         ClassId: "3", CharaId: "3", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "PlayerA", SleeveId: "3000011",
-        EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0, BattleType: 11);
+        EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);
 
     private static MatchContext CtxB() => new(
         SelfDeckCardIds: Enumerable.Range(1, 30).Select(_ => 200_011_010L).ToList(),
         ClassId: "5", CharaId: "5", CardMasterName: "card_master_node_10015",
         CountryCode: "JPN", UserName: "PlayerB", SleeveId: "3000022",
-        EmblemId: "701441022", DegreeId: "300004", FieldId: 44, IsOfficial: 0, BattleType: 11);
+        EmblemId: "701441022", DegreeId: "300004", FieldId: 44, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);
 
     /// <summary>Tracks the peak number of dispatches in flight at once. Records the count under a
     /// short lock, then holds (outside the lock) to widen the overlap window so a serialization bug

SVSim.UnitTests/BattleNode/Sessions/BattleSessionDispatchTests.cs

@@ -894,7 +894,7 @@ public class BattleSessionDispatchTests
         SelfDeckCardIds: Array.Empty<long>(),
         ClassId: "0", CharaId: "0", CardMasterName: "card_master_node_10015",
         CountryCode: "", UserName: "Bot", SleeveId: "0",
-        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 0);
+        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleModeId: 0);
 
     [Test]
     public void Bot_InitNetwork_acks_to_sender()
@@ -1051,21 +1051,21 @@ public class BattleSessionDispatchTests
         ClassId: "3", CharaId: "3", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "PlayerA", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     private static MatchContext PlayerBCtx() => new(
         SelfDeckCardIds: Enumerable.Range(1, 30).Select(_ => 200_011_010L).ToList(),
         ClassId: "5", CharaId: "5", CardMasterName: "card_master_node_10015",
         CountryCode: "JPN", UserName: "PlayerB", SleeveId: "3000022",
         EmblemId: "701441022", DegreeId: "300004", FieldId: 44, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     private static MatchContext FixtureCtx() => new(
         SelfDeckCardIds: Enumerable.Range(1, 30).Select(_ => 100_011_010L).ToList(),
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     private static MsgEnvelope NewEnvelope(NetworkBattleUri uri) =>
         new(uri, ViewerId: 1, Uuid: "u", Bid: null, RetryAttempt: 0,

SVSim.UnitTests/BattleNode/Sessions/BattleSessionStateTests.cs

@@ -24,7 +24,7 @@ public class BattleSessionStateTests
     private static MatchContext Ctx(params long[] deck) => new(
         SelfDeckCardIds: deck, ClassId: "1", CharaId: "1", CardMasterName: "cm",
         CountryCode: "KOR", UserName: "P", SleeveId: "0", EmblemId: "0", DegreeId: "0",
-        FieldId: 0, IsOfficial: 0, BattleType: 11);
+        FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);
 
     [Test]
     public void GetOrSeedDeckMap_maps_idx_1based_to_the_shuffled_order()

SVSim.UnitTests/BattleNode/Sessions/BattleSessionTerminateCascadeTests.cs

@@ -54,5 +54,5 @@ public class BattleSessionTerminateCascadeTests
         SelfDeckCardIds: Array.Empty<long>(),
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "JP", UserName: "Test", SleeveId: "0",
-        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 11);
+        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);
 }

SVSim.UnitTests/BattleNode/Sessions/InMemoryBattleSessionStoreTests.cs

@@ -48,5 +48,5 @@ public class InMemoryBattleSessionStoreTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 }

SVSim.UnitTests/BattleNode/Sessions/Participants/RealParticipantHandEventTests.cs

@@ -150,5 +150,5 @@ public class RealParticipantHandEventTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 }

SVSim.UnitTests/BattleNode/Sessions/Participants/RealParticipantTests.cs

@@ -174,7 +174,7 @@ public class RealParticipantTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 
     private static MsgEnvelope NewEnvelope(NetworkBattleUri uri) =>
         new(uri, ViewerId: 1, Uuid: "u", Bid: null, RetryAttempt: 0,

SVSim.UnitTests/Matching/BotRosterTests.cs

@@ -14,7 +14,7 @@ public class BotRosterTests
         SelfDeckCardIds: Array.Empty<long>(),
         ClassId: classId, CharaId: classId, CardMasterName: "card_master_node_10015",
         CountryCode: "JP", UserName: userName, SleeveId: "0",
-        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 11);
+        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo);
 
     private static async Task<BotRoster> NewRosterAsync(SVSimTestFactory factory)
     {

SVSim.UnitTests/Matching/InProcessPairUpRankFallbackTests.cs

@@ -48,7 +48,7 @@ public class InProcessPairUpRankFallbackTests
             SelfDeckCardIds: Array.Empty<long>(), ClassId: "0", CharaId: "0",
             CardMasterName: "card_master_node_10015",
             CountryCode: "JP", UserName: $"P{id}", SleeveId: "0",
-            EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 11));
+            EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo));
 
     [Test]
     public async Task TK2_policy_is_PvpOnly_no_fallback_regression()

SVSim.UnitTests/Matching/InProcessPairUpTests.cs

@@ -94,5 +94,5 @@ public class InProcessPairUpTests
         ClassId: "1", CharaId: "1", CardMasterName: "card_master_node_10015",
         CountryCode: "KOR", UserName: "Player", SleeveId: "3000011",
         EmblemId: "701441011", DegreeId: "300003", FieldId: 43, IsOfficial: 0,
-        BattleType: 11);
+        BattleModeId: BattleModes.TakeTwo);
 }

SVSim.UnitTests/Matching/MatchingResolverTests.cs

@@ -31,7 +31,7 @@ public class MatchingResolverTests
             SelfDeckCardIds: Array.Empty<long>(), ClassId: "0", CharaId: "0",
             CardMasterName: "card_master_node_10015",
             CountryCode: "JP", UserName: $"P{vid}", SleeveId: "0",
-            EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 11));
+            EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleModeId: BattleModes.TakeTwo));
 
     [Test]
     public async Task When_neither_flag_set_calls_pairUp_and_parks_returns_3002_with_empty_url()

SVSim.UnitTests/Services/MatchContextBuilderTests.cs

@@ -64,7 +64,7 @@ public class MatchContextBuilderTests
         Assert.That(ctx.EmblemId, Is.EqualTo(emblemId.ToString()));
         Assert.That(ctx.DegreeId, Is.EqualTo(degreeId.ToString()));
         Assert.That(ctx.IsOfficial, Is.EqualTo(0));
-        Assert.That(ctx.BattleType, Is.EqualTo(11));
+        Assert.That(ctx.BattleModeId, Is.EqualTo(BattleModes.TakeTwo));
         // Hardcoded v1 fixtures (see spec §Deferred plumbing)
         Assert.That(ctx.CardMasterName, Is.EqualTo("card_master_node_10015"));
         Assert.That(ctx.FieldId, Is.EqualTo(43));
@@ -131,7 +131,7 @@ public class MatchContextBuilderTests
         var ctx = await builder.BuildForRankBattleAsync(viewerId, Format.Rotation, deckNo: 1);
 
         Assert.That(ctx.UserName, Is.EqualTo("Ranker"));
-        Assert.That(ctx.BattleType, Is.EqualTo(11), "BattleType=11 matches the prod rank-battle wire value (same as TK2).");
+        Assert.That(ctx.BattleModeId, Is.EqualTo(BattleModes.TakeTwo), "rank-battle carries the same mode id as TK2 on the wire.");
         Assert.That(ctx.ClassId, Is.Not.Null.And.Not.Empty, "ClassId from the selected deck's class.");
         Assert.That(ctx.CardMasterName, Is.EqualTo("card_master_node_10015"));
         Assert.That(ctx.FieldId, Is.EqualTo(43));