Restructure solution layout by module

src/Policy/StellaOps.Policy.Engine/Services/InMemoryPolicyPackRepository.cs

@@ -0,0 +1,93 @@
+using System.Collections.Concurrent;
+using StellaOps.Policy.Engine.Domain;
+
+namespace StellaOps.Policy.Engine.Services;
+
+internal sealed class InMemoryPolicyPackRepository : IPolicyPackRepository
+{
+    private readonly ConcurrentDictionary<string, PolicyPackRecord> packs = new(StringComparer.OrdinalIgnoreCase);
+
+    public Task<PolicyPackRecord> CreateAsync(string packId, string? displayName, CancellationToken cancellationToken)
+    {
+        ArgumentNullException.ThrowIfNull(packId);
+
+        var created = packs.GetOrAdd(packId, id => new PolicyPackRecord(id, displayName, DateTimeOffset.UtcNow));
+        return Task.FromResult(created);
+    }
+
+    public Task<IReadOnlyList<PolicyPackRecord>> ListAsync(CancellationToken cancellationToken)
+    {
+        IReadOnlyList<PolicyPackRecord> list = packs.Values
+            .OrderBy(pack => pack.PackId, StringComparer.Ordinal)
+            .ToList();
+        return Task.FromResult(list);
+    }
+
+    public Task<PolicyRevisionRecord> UpsertRevisionAsync(string packId, int version, bool requiresTwoPersonApproval, PolicyRevisionStatus initialStatus, CancellationToken cancellationToken)
+    {
+        var pack = packs.GetOrAdd(packId, id => new PolicyPackRecord(id, null, DateTimeOffset.UtcNow));
+        int revisionVersion = version > 0 ? version : pack.GetNextVersion();
+        var revision = pack.GetOrAddRevision(
+            revisionVersion,
+            v => new PolicyRevisionRecord(v, requiresTwoPersonApproval, initialStatus, DateTimeOffset.UtcNow));
+
+        if (revision.Status != initialStatus)
+        {
+            revision.SetStatus(initialStatus, DateTimeOffset.UtcNow);
+        }
+
+        return Task.FromResult(revision);
+    }
+
+    public Task<PolicyRevisionRecord?> GetRevisionAsync(string packId, int version, CancellationToken cancellationToken)
+    {
+        if (!packs.TryGetValue(packId, out var pack))
+        {
+            return Task.FromResult<PolicyRevisionRecord?>(null);
+        }
+
+        return Task.FromResult(pack.TryGetRevision(version, out var revision) ? revision : null);
+    }
+
+    public Task<PolicyActivationResult> RecordActivationAsync(string packId, int version, string actorId, DateTimeOffset timestamp, string? comment, CancellationToken cancellationToken)
+    {
+        if (!packs.TryGetValue(packId, out var pack))
+        {
+            return Task.FromResult(new PolicyActivationResult(PolicyActivationResultStatus.PackNotFound, null));
+        }
+
+        if (!pack.TryGetRevision(version, out var revision))
+        {
+            return Task.FromResult(new PolicyActivationResult(PolicyActivationResultStatus.RevisionNotFound, null));
+        }
+
+        if (revision.Status == PolicyRevisionStatus.Active)
+        {
+            return Task.FromResult(new PolicyActivationResult(PolicyActivationResultStatus.AlreadyActive, revision));
+        }
+
+        if (revision.Status != PolicyRevisionStatus.Approved)
+        {
+            return Task.FromResult(new PolicyActivationResult(PolicyActivationResultStatus.NotApproved, revision));
+        }
+
+        var approvalStatus = revision.AddApproval(new PolicyActivationApproval(actorId, timestamp, comment));
+        return Task.FromResult(approvalStatus switch
+        {
+            PolicyActivationApprovalStatus.Duplicate => new PolicyActivationResult(PolicyActivationResultStatus.DuplicateApproval, revision),
+            PolicyActivationApprovalStatus.Pending when revision.RequiresTwoPersonApproval
+                => new PolicyActivationResult(PolicyActivationResultStatus.PendingSecondApproval, revision),
+            PolicyActivationApprovalStatus.Pending =>
+                ActivateRevision(revision, timestamp),
+            PolicyActivationApprovalStatus.ThresholdReached =>
+                ActivateRevision(revision, timestamp),
+            _ => throw new InvalidOperationException("Unknown activation approval status.")
+        });
+    }
+
+    private static PolicyActivationResult ActivateRevision(PolicyRevisionRecord revision, DateTimeOffset timestamp)
+    {
+        revision.SetStatus(PolicyRevisionStatus.Active, timestamp);
+        return new PolicyActivationResult(PolicyActivationResultStatus.Activated, revision);
+    }
+}