feat(server): implement sealed share lifecycle

Signed-off-by: JustMe <mr.toing@outlook.com>

server/tests/WebDrop.Core.Tests/TestEnv.cs

@@ -0,0 +1,105 @@
+using System.Buffers.Binary;
+using System.Security.Cryptography;
+using WebDrop.Core;
+using WebDrop.Storage;
+
+namespace WebDrop.Core.Tests;
+
+public sealed class FakeClock : IClock
+{
+    public long NowMs { get; set; } = 1_700_000_000_000;
+    public void Advance(TimeSpan span) => NowMs += (long)span.TotalMilliseconds;
+}
+
+public sealed class RecordingEvents : IChannelEvents
+{
+    public List<(Id16 Channel, long Seq)> Advances { get; } = [];
+    public int Settings, Seats, Deleted;
+    public void Advanced(Id16 channelId, long seq) { lock (Advances) Advances.Add((channelId, seq)); }
+    public void SettingsChanged(Id16 channelId) => Interlocked.Increment(ref Settings);
+    public void SeatsChanged(Id16 channelId) => Interlocked.Increment(ref Seats);
+    public void ChannelDeleted(Id16 channelId) => Interlocked.Increment(ref Deleted);
+}
+
+/// <summary>一个频道的全部凭据,模拟客户端从 K / A 派生出的令牌。</summary>
+public sealed class TestChannel(Id16 id, ChannelMode mode, byte[] read, byte[] write, byte[] owner)
+{
+    public Id16 Id { get; } = id;
+    public ChannelMode Mode { get; } = mode;
+    public byte[] ReadToken { get; } = read;
+    public byte[] WriteToken { get; } = write;
+    public byte[] OwnerToken { get; } = owner;
+
+    public Credentials Owner(byte[] endpoint) => new(Role.Owner, OwnerToken, endpoint);
+    public Credentials Member(byte[] endpoint) => new(Role.Write, WriteToken, endpoint);
+    public Credentials Reader(byte[] endpoint) => new(Role.Read, ReadToken, endpoint);
+}
+
+public sealed class TestEnv : IDisposable
+{
+    public string Dir { get; } = Path.Combine(Path.GetTempPath(), "webdrop-tests-" + Guid.NewGuid().ToString("N"));
+    public FakeClock Clock { get; } = new();
+    public RecordingEvents Events { get; } = new();
+    public ServerLimits Limits { get; } = new();
+    public SqliteChannelStore Store { get; }
+    public DiskBlobStore Blobs { get; }
+    public ChannelService Service { get; private set; }
+
+    public TestEnv()
+    {
+        Directory.CreateDirectory(Dir);
+        Store = new SqliteChannelStore(Path.Combine(Dir, "test.db"));
+        Blobs = new DiskBlobStore(Path.Combine(Dir, "blobs"));
+        Service = new ChannelService(Store, Blobs, Clock, Limits, Events);
+    }
+
+    public static byte[] Random(int n) => RandomNumberGenerator.GetBytes(n);
+    public static byte[] Endpoint() => TokenHash.Compute(Random(32));
+    public static Id16 NewId() => Id16.FromBytes(Random(16));
+
+    public TestChannel Create(
+        byte[] ownerEndpoint,
+        ChannelMode mode = ChannelMode.Enc,
+        ChannelSettings? settings = null,
+        bool withWriteHash = true)
+    {
+        var id = NewId();
+        var read = Random(32);
+        var write = Random(32);
+        var owner = Random(32);
+
+        Service.CreateChannel(new CreateChannelRequest
+        {
+            Id = id.ToBase64Url(),
+            Mode = mode,
+            Settings = settings,
+            ReadHash = mode == ChannelMode.Enc ? Codec.Encode(TokenHash.Compute(read)) : null,
+            WriteHash = withWriteHash ? Codec.Encode(TokenHash.Compute(write)) : null,
+            OwnerHash = Codec.Encode(TokenHash.Compute(owner)),
+        }, ownerEndpoint);
+
+        return new TestChannel(id, mode, read, write, owner);
+    }
+
+    /// <summary>构造一个封装。enc 模式的负载长度必须是 档位+16。</summary>
+    public static byte[] Frame(Id16 item, uint index, FrameFlags flags, int payloadLength, byte fill = 0x42)
+    {
+        var bytes = new byte[Envelope.HeaderSize + payloadLength];
+        bytes[0] = Envelope.Version;
+        bytes[1] = (byte)flags;
+        item.WriteTo(bytes.AsSpan(2));
+        BinaryPrimitives.WriteUInt32BigEndian(bytes.AsSpan(18), index);
+        BinaryPrimitives.WriteUInt32BigEndian(bytes.AsSpan(22), (uint)payloadLength);
+        bytes.AsSpan(Envelope.HeaderSize).Fill(fill);
+        return bytes;
+    }
+
+    public const int EncPayload = 1024 + 16;
+    public const FrameFlags SmallEnc = FrameFlags.Final | FrameFlags.Enc;
+
+    public void Dispose()
+    {
+        Store.Dispose();
+        try { Directory.Delete(Dir, recursive: true); } catch (IOException) { }
+    }
+}