Restructure solution layout by module

src/Policy/StellaOps.Policy.Engine/Domain/PolicyPackRecord.cs

@@ -0,0 +1,101 @@
+using System.Collections.Concurrent;
+using System.Collections.Immutable;
+
+namespace StellaOps.Policy.Engine.Domain;
+
+internal sealed class PolicyPackRecord
+{
+    private readonly ConcurrentDictionary<int, PolicyRevisionRecord> revisions = new();
+
+    public PolicyPackRecord(string packId, string? displayName, DateTimeOffset createdAt)
+    {
+        PackId = packId ?? throw new ArgumentNullException(nameof(packId));
+        DisplayName = displayName;
+        CreatedAt = createdAt;
+    }
+
+    public string PackId { get; }
+
+    public string? DisplayName { get; }
+
+    public DateTimeOffset CreatedAt { get; }
+
+    public ImmutableArray<PolicyRevisionRecord> GetRevisions()
+        => revisions.Values
+            .OrderBy(r => r.Version)
+            .ToImmutableArray();
+
+    public PolicyRevisionRecord GetOrAddRevision(int version, Func<int, PolicyRevisionRecord> factory)
+        => revisions.GetOrAdd(version, factory);
+
+    public bool TryGetRevision(int version, out PolicyRevisionRecord revision)
+        => revisions.TryGetValue(version, out revision!);
+
+    public int GetNextVersion()
+        => revisions.IsEmpty ? 1 : revisions.Keys.Max() + 1;
+}
+
+internal sealed class PolicyRevisionRecord
+{
+    private readonly ConcurrentDictionary<string, PolicyActivationApproval> approvals = new(StringComparer.OrdinalIgnoreCase);
+
+    public PolicyRevisionRecord(int version, bool requiresTwoPerson, PolicyRevisionStatus status, DateTimeOffset createdAt)
+    {
+        Version = version;
+        RequiresTwoPersonApproval = requiresTwoPerson;
+        Status = status;
+        CreatedAt = createdAt;
+    }
+
+    public int Version { get; }
+
+    public bool RequiresTwoPersonApproval { get; }
+
+    public PolicyRevisionStatus Status { get; private set; }
+
+    public DateTimeOffset CreatedAt { get; }
+
+    public DateTimeOffset? ActivatedAt { get; private set; }
+
+    public ImmutableArray<PolicyActivationApproval> Approvals
+        => approvals.Values
+            .OrderBy(approval => approval.ApprovedAt)
+            .ToImmutableArray();
+
+    public void SetStatus(PolicyRevisionStatus status, DateTimeOffset timestamp)
+    {
+        Status = status;
+        if (status == PolicyRevisionStatus.Active)
+        {
+            ActivatedAt = timestamp;
+        }
+    }
+
+    public PolicyActivationApprovalStatus AddApproval(PolicyActivationApproval approval)
+    {
+        if (!approvals.TryAdd(approval.ActorId, approval))
+        {
+            return PolicyActivationApprovalStatus.Duplicate;
+        }
+
+        return approvals.Count >= 2
+            ? PolicyActivationApprovalStatus.ThresholdReached
+            : PolicyActivationApprovalStatus.Pending;
+    }
+}
+
+internal enum PolicyRevisionStatus
+{
+    Draft,
+    Approved,
+    Active
+}
+
+internal sealed record PolicyActivationApproval(string ActorId, DateTimeOffset ApprovedAt, string? Comment);
+
+internal enum PolicyActivationApprovalStatus
+{
+    Pending,
+    ThresholdReached,
+    Duplicate
+}