From 0b38b82b47249f0b04866b798ade550e629b2c0b Mon Sep 17 00:00:00 2001
From: halgari <tbaldridge@gmail.com>
Date: Fri, 12 Jan 2024 15:01:06 -0700
Subject: [PATCH] WIP

---
 .../RocksDBEventStore.cs                      | 34 ++++++++++---------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/src/NexusMods.EventSourcing.RocksDB/RocksDBEventStore.cs b/src/NexusMods.EventSourcing.RocksDB/RocksDBEventStore.cs
index 18223667..594020df 100644
--- a/src/NexusMods.EventSourcing.RocksDB/RocksDBEventStore.cs
+++ b/src/NexusMods.EventSourcing.RocksDB/RocksDBEventStore.cs
@@ -3,12 +3,13 @@
 using System.Buffers.Binary;
 using System.Collections.Generic;
 using NexusMods.EventSourcing.Abstractions;
+using NexusMods.EventSourcing.Serialization;
 using Reloaded.Memory.Extensions;
 using RocksDbSharp;
 
 namespace NexusMods.EventSourcing.RocksDB;
 
-public class RocksDBEventStore<TSerializer> : IEventStore
+public sealed class RocksDBEventStore<TSerializer> : AEventStore
     where TSerializer : IEventSerializer
 {
     private readonly ColumnFamilies _families;
@@ -18,8 +19,9 @@ public class RocksDBEventStore<TSerializer> : IEventStore
     private readonly ColumnFamilyHandle _entityIndexColumn;
     private readonly TSerializer _serializer;
     private readonly SpanDeserializer<TSerializer> _deserializer;
+    private readonly ColumnFamilyHandle _snapshotColumn;
 
-    public RocksDBEventStore(TSerializer serializer, Settings settings)
+    public RocksDBEventStore(TSerializer serializer, Settings settings, SerializationRegistry serializationRegistry) : base(serializationRegistry)
     {
         _serializer = serializer;
         _families = new ColumnFamilies();
@@ -31,20 +33,20 @@ public RocksDBEventStore(TSerializer serializer, Settings settings)
             settings.StorageLocation.ToString(), new ColumnFamilies());
         _eventsColumn = _db.CreateColumnFamily(new ColumnFamilyOptions(), "events");
         _entityIndexColumn = _db.CreateColumnFamily(new ColumnFamilyOptions(), "entityIndex");
-        //_eventsColumn = _db.GetColumnFamily("events");
-        //_entityIndexColumn = _db.GetColumnFamily("entityIndex");
+        _snapshotColumn = _db.CreateColumnFamily(new ColumnFamilyOptions(), "snapshots");
         _tx = TransactionId.From(0);
 
         _deserializer = new SpanDeserializer<TSerializer>(serializer);
     }
 
 
-    public TransactionId Add<T>(T eventValue) where T : IEvent
+    public override TransactionId Add<T>(T eventValue)
     {
         lock (this)
         {
              _tx = _tx.Next();
 
+             // Write the event itself
              {
                  Span<byte> keySpan = stackalloc byte[8];
                  _tx.WriteTo(keySpan);
@@ -52,6 +54,7 @@ public TransactionId Add<T>(T eventValue) where T : IEvent
                  _db.Put(keySpan, span, _eventsColumn);
              }
 
+             // Update the entity indexes to mark them as having this event
              {
                  var ingester = new ModifiedEntitiesIngester();
                  eventValue.Apply(ingester);
@@ -67,20 +70,14 @@ public TransactionId Add<T>(T eventValue) where T : IEvent
         }
     }
 
-    public void EventsForEntity<TIngester>(EntityId entityId, TIngester ingester, TransactionId fromId, TransactionId toId) where TIngester : IEventIngester
-    {
-        throw new NotImplementedException();
-    }
-
-
-
-    public void EventsForEntity<TIngester>(EntityId entityId, TIngester ingester) where TIngester : IEventIngester
+    public override void EventsForEntity<TIngester>(EntityId entityId, TIngester ingester, TransactionId fromId, TransactionId toId)
     {
         Span<byte> startKey = stackalloc byte[24];
         entityId.TryWriteBytes(startKey);
+        BinaryPrimitives.WriteUInt64BigEndian(startKey.SliceFast(16), fromId.Value);
         Span<byte> endKey = stackalloc byte[24];
         entityId.TryWriteBytes(endKey);
-        BinaryPrimitives.WriteUInt64BigEndian(endKey[16..], ulong.MaxValue);
+        BinaryPrimitives.WriteUInt64BigEndian(endKey.SliceFast(16), toId.Value);
 
         var options = new ReadOptions();
         unsafe
@@ -113,8 +110,13 @@ public TransactionId GetSnapshot(TransactionId asOf, EntityId entityId, out IAcc
         throw new NotImplementedException();
     }
 
-    public void SetSnapshot(TransactionId txId, EntityId id, IDictionary<IAttribute, IAccumulator> attributes)
+    public override void SetSnapshot(TransactionId txId, EntityId id, IDictionary<IAttribute, IAccumulator> attributes)
     {
-        throw new NotImplementedException();
+        var span = SerializeSnapshot(id, attributes);
+
+        Span<byte> keySpan = stackalloc byte[24];
+        id.TryWriteBytes(keySpan);
+        BinaryPrimitives.WriteUInt64BigEndian(keySpan.SliceFast(16), txId.Value);
+        _db.Put(keySpan, span, _snapshotColumn);
     }
 }