Phase 3b: Repository-Schicht im Core (Interfaces + Mongo-Impl + DI)

- Interfaces: IAccountRepository, IMarketRepository, IPositionRepository
  (IPositionRepository kapselt das Collection-per-Account-Muster).
- Mongo-Implementierungen bilden die bisherige Shim-Semantik 1:1 mit direkten
  MongoDB.Driver-Aufrufen nach (kein App-Shim-Bezug im Core).
- AddCorePersistence()-Erweiterung + Registrierung in Program.cs.
- Noch keine Call-Sites umgestellt; Build 0 Fehler.

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

Program.cs

@@ -8,6 +8,7 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Options;
 using PolyTrader.Core.Configuration;
+using PolyTrader.Core.DependencyInjection;
 using PolyTraderSharp.Models;
 using PolyTraderSharp.Services;
 
@@ -33,6 +34,7 @@ internal static class Program
 					var client = new MongoClient(dbOptions.ConnectionString);
 					return client.GetDatabase(dbOptions.DatabaseName);
 				});
+				services.AddCorePersistence();
 				services.AddSingleton((IServiceProvider sp) => ServerSettings.Load("server_settings.xml"));
 				services.AddSingleton<TradingState>();
 				services.AddSingleton(copySignalChannel.Writer);

src/PolyTrader.Core/DependencyInjection/ServiceCollectionExtensions.cs

@@ -0,0 +1,21 @@
+using Microsoft.Extensions.DependencyInjection;
+using PolyTrader.Core.Persistence;
+using PolyTrader.Core.Persistence.Mongo;
+
+namespace PolyTrader.Core.DependencyInjection
+{
+    public static class ServiceCollectionExtensions
+    {
+        /// <summary>
+        /// Registriert die Core-Persistenzschicht (Repository-Interfaces + Mongo-Implementierungen).
+        /// Setzt eine registrierte IMongoDatabase voraus.
+        /// </summary>
+        public static IServiceCollection AddCorePersistence(this IServiceCollection services)
+        {
+            services.AddSingleton<IAccountRepository, MongoAccountRepository>();
+            services.AddSingleton<IMarketRepository, MongoMarketRepository>();
+            services.AddSingleton<IPositionRepository, MongoPositionRepository>();
+            return services;
+        }
+    }
+}

src/PolyTrader.Core/Persistence/IAccountRepository.cs

@@ -0,0 +1,15 @@
+using System.Collections.Generic;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence
+{
+    /// <summary>
+    /// Zugriff auf die eigenen Trading-Accounts (Collection "accounts").
+    /// </summary>
+    public interface IAccountRepository
+    {
+        List<AccountState> GetAll();
+        void Upsert(AccountState account);
+        void Delete(int accountId);
+    }
+}

src/PolyTrader.Core/Persistence/IMarketRepository.cs

@@ -0,0 +1,27 @@
+using System.Collections.Generic;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence
+{
+    /// <summary>
+    /// Zugriff auf die Markt-Metadaten (Collection "markets").
+    /// </summary>
+    public interface IMarketRepository
+    {
+        MarketData? GetById(string id);
+
+        /// <summary>Findet den Markt, dessen ClobTokenIds die angegebene TokenId enthalten.</summary>
+        MarketData? FindByTokenId(string tokenId);
+
+        /// <summary>Alle nicht geschlossenen Märkte.</summary>
+        List<MarketData> GetActive();
+
+        void Upsert(MarketData market);
+        void Insert(MarketData market);
+
+        /// <summary>Aktualisiert einen vorhandenen Markt ohne Upsert.</summary>
+        void Update(MarketData market);
+
+        void EnsureIndexes();
+    }
+}

src/PolyTrader.Core/Persistence/IPositionRepository.cs

@@ -0,0 +1,27 @@
+using System.Collections.Generic;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence
+{
+    /// <summary>
+    /// Zugriff auf die offenen Positionen je Account. Kapselt das aktuelle
+    /// Collection-per-Account-Muster ("open_positions_{id}" / "demo_positions_{id}").
+    /// In der späteren MySQL-Migration wird daraus eine Tabelle mit account_id/is_demo.
+    /// </summary>
+    public interface IPositionRepository
+    {
+        List<Position> GetLive(int accountId);
+        List<Position> GetDemo(int accountId);
+
+        Position? FindLive(int accountId, string tokenId);
+        Position? FindDemo(int accountId, string tokenId);
+
+        void UpsertLive(int accountId, Position position);
+        void UpsertDemo(int accountId, Position position);
+
+        void DeleteLive(int accountId, string tokenId);
+        void DeleteDemo(int accountId, string tokenId);
+
+        void DropDemo(int accountId);
+    }
+}

src/PolyTrader.Core/Persistence/Mongo/MongoAccountRepository.cs

@@ -0,0 +1,24 @@
+using System.Collections.Generic;
+using System.Linq;
+using MongoDB.Driver;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence.Mongo
+{
+    public class MongoAccountRepository : IAccountRepository
+    {
+        private readonly IMongoCollection<AccountState> _col;
+
+        public MongoAccountRepository(IMongoDatabase db)
+        {
+            _col = db.GetCollection<AccountState>("accounts");
+        }
+
+        public List<AccountState> GetAll() => _col.Find(_ => true).ToList();
+
+        public void Upsert(AccountState account) =>
+            _col.ReplaceOne(x => x.AccountId == account.AccountId, account, new ReplaceOptions { IsUpsert = true });
+
+        public void Delete(int accountId) => _col.DeleteMany(x => x.AccountId == accountId);
+    }
+}

src/PolyTrader.Core/Persistence/Mongo/MongoMarketRepository.cs

@@ -0,0 +1,41 @@
+using System.Collections.Generic;
+using System.Linq;
+using MongoDB.Driver;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence.Mongo
+{
+    public class MongoMarketRepository : IMarketRepository
+    {
+        private readonly IMongoCollection<MarketData> _col;
+
+        public MongoMarketRepository(IMongoDatabase db)
+        {
+            _col = db.GetCollection<MarketData>("markets");
+        }
+
+        public MarketData? GetById(string id) => _col.Find(x => x.Id == id).FirstOrDefault();
+
+        public MarketData? FindByTokenId(string tokenId) =>
+            _col.Find(x => x.ClobTokenIds != null && x.ClobTokenIds.Contains(tokenId)).FirstOrDefault();
+
+        public List<MarketData> GetActive() => _col.Find(x => !x.Closed).ToList();
+
+        public void Upsert(MarketData market) =>
+            _col.ReplaceOne(x => x.Id == market.Id, market, new ReplaceOptions { IsUpsert = true });
+
+        public void Insert(MarketData market) => _col.InsertOne(market);
+
+        public void Update(MarketData market) => _col.ReplaceOne(x => x.Id == market.Id, market);
+
+        public void EnsureIndexes()
+        {
+            try
+            {
+                var keys = Builders<MarketData>.IndexKeys.Ascending(x => x.Id);
+                _col.Indexes.CreateOne(new CreateIndexModel<MarketData>(keys));
+            }
+            catch { }
+        }
+    }
+}

src/PolyTrader.Core/Persistence/Mongo/MongoPositionRepository.cs

@@ -0,0 +1,46 @@
+using System.Collections.Generic;
+using System.Linq;
+using MongoDB.Driver;
+using PolyTraderSharp.Models;
+
+namespace PolyTrader.Core.Persistence.Mongo
+{
+    public class MongoPositionRepository : IPositionRepository
+    {
+        private readonly IMongoDatabase _db;
+
+        public MongoPositionRepository(IMongoDatabase db)
+        {
+            _db = db;
+        }
+
+        private IMongoCollection<Position> Live(int accountId) =>
+            _db.GetCollection<Position>($"open_positions_{accountId}");
+
+        private IMongoCollection<Position> Demo(int accountId) =>
+            _db.GetCollection<Position>($"demo_positions_{accountId}");
+
+        public List<Position> GetLive(int accountId) => Live(accountId).Find(_ => true).ToList();
+        public List<Position> GetDemo(int accountId) => Demo(accountId).Find(_ => true).ToList();
+
+        public Position? FindLive(int accountId, string tokenId) =>
+            Live(accountId).Find(x => x.TokenId == tokenId).FirstOrDefault();
+
+        public Position? FindDemo(int accountId, string tokenId) =>
+            Demo(accountId).Find(x => x.TokenId == tokenId).FirstOrDefault();
+
+        public void UpsertLive(int accountId, Position position) =>
+            Live(accountId).ReplaceOne(x => x.TokenId == position.TokenId, position, new ReplaceOptions { IsUpsert = true });
+
+        public void UpsertDemo(int accountId, Position position) =>
+            Demo(accountId).ReplaceOne(x => x.TokenId == position.TokenId, position, new ReplaceOptions { IsUpsert = true });
+
+        public void DeleteLive(int accountId, string tokenId) =>
+            Live(accountId).DeleteOne(x => x.TokenId == tokenId);
+
+        public void DeleteDemo(int accountId, string tokenId) =>
+            Demo(accountId).DeleteOne(x => x.TokenId == tokenId);
+
+        public void DropDemo(int accountId) => _db.DropCollection($"demo_positions_{accountId}");
+    }
+}

src/PolyTrader.Core/PolyTrader.Core.csproj

@@ -8,6 +8,7 @@
 
   <ItemGroup>
     <PackageReference Include="MongoDB.Driver" Version="2.24.0" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.0" />
   </ItemGroup>
 
 </Project>