1  using GUNRPG.Application.Backend;
 2  using LiteDB;
 3  
 4  namespace GUNRPG.Infrastructure.Persistence;
 5  
 6  public sealed class LiteDbOfflineSyncHeadStore : IOfflineSyncHeadStore
 7  {
 8      private readonly ILiteCollection<OfflineSyncHeadDocument> _heads;
 9      private readonly object _syncLock = new();
10  
11      public LiteDbOfflineSyncHeadStore(LiteDatabase database)
12      {
13          _heads = database.GetCollection<OfflineSyncHeadDocument>("offline_sync_heads");
14          _heads.EnsureIndex(x => x.OperatorId, true);
15      }
16  
17      public Task<OfflineSyncHead?> GetAsync(Guid operatorId)
18      {
19          lock (_syncLock)
20          {
21              var doc = _heads.FindById(operatorId.ToString());
22              if (doc == null)
23              {
24                  return Task.FromResult<OfflineSyncHead?>(null);
25              }
26  
27              return Task.FromResult<OfflineSyncHead?>(new OfflineSyncHead
28              {
29                  OperatorId = doc.OperatorId,
30                  SequenceNumber = doc.SequenceNumber,
31                  ResultOperatorStateHash = doc.ResultOperatorStateHash
32              });
33          }
34      }
35  
36      public Task UpsertAsync(OfflineSyncHead head)
37      {
38          lock (_syncLock)
39          {
40              _heads.Upsert(new OfflineSyncHeadDocument
41              {
42                  Id = head.OperatorId.ToString(),
43                  OperatorId = head.OperatorId,
44                  SequenceNumber = head.SequenceNumber,
45                  ResultOperatorStateHash = head.ResultOperatorStateHash
46              });
47          }
48  
49          return Task.CompletedTask;
50      }
51  
52      private sealed class OfflineSyncHeadDocument
53      {
54          public string Id { get; init; } = string.Empty;
55          public Guid OperatorId { get; init; }
56          public long SequenceNumber { get; init; }
57          public string ResultOperatorStateHash { get; init; } = string.Empty;
58      }
59  }