Rename Concelier Source modules to Connector

src/StellaOps.Concelier.Connector.Kisa/Internal/KisaCursor.cs

@@ -0,0 +1,120 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using MongoDB.Bson;
+
+namespace StellaOps.Concelier.Connector.Kisa.Internal;
+
+internal sealed record KisaCursor(
+    IReadOnlyCollection<Guid> PendingDocuments,
+    IReadOnlyCollection<Guid> PendingMappings,
+    IReadOnlyCollection<string> KnownIds,
+    DateTimeOffset? LastPublished,
+    DateTimeOffset? LastFetchAt)
+{
+    private static readonly IReadOnlyCollection<Guid> EmptyGuids = Array.Empty<Guid>();
+    private static readonly IReadOnlyCollection<string> EmptyStrings = Array.Empty<string>();
+
+    public static KisaCursor Empty { get; } = new(EmptyGuids, EmptyGuids, EmptyStrings, null, null);
+
+    public KisaCursor WithPendingDocuments(IEnumerable<Guid> documents)
+        => this with { PendingDocuments = Distinct(documents) };
+
+    public KisaCursor WithPendingMappings(IEnumerable<Guid> mappings)
+        => this with { PendingMappings = Distinct(mappings) };
+
+    public KisaCursor WithKnownIds(IEnumerable<string> ids)
+        => this with { KnownIds = ids?.Distinct(StringComparer.OrdinalIgnoreCase).ToArray() ?? EmptyStrings };
+
+    public KisaCursor WithLastPublished(DateTimeOffset? published)
+        => this with { LastPublished = published };
+
+    public KisaCursor WithLastFetch(DateTimeOffset? timestamp)
+        => this with { LastFetchAt = timestamp };
+
+    public BsonDocument ToBsonDocument()
+    {
+        var document = new BsonDocument
+        {
+            ["pendingDocuments"] = new BsonArray(PendingDocuments.Select(id => id.ToString())),
+            ["pendingMappings"] = new BsonArray(PendingMappings.Select(id => id.ToString())),
+            ["knownIds"] = new BsonArray(KnownIds),
+        };
+
+        if (LastPublished.HasValue)
+        {
+            document["lastPublished"] = LastPublished.Value.UtcDateTime;
+        }
+
+        if (LastFetchAt.HasValue)
+        {
+            document["lastFetchAt"] = LastFetchAt.Value.UtcDateTime;
+        }
+
+        return document;
+    }
+
+    public static KisaCursor FromBson(BsonDocument? document)
+    {
+        if (document is null || document.ElementCount == 0)
+        {
+            return Empty;
+        }
+
+        var pendingDocuments = ReadGuidArray(document, "pendingDocuments");
+        var pendingMappings = ReadGuidArray(document, "pendingMappings");
+        var knownIds = ReadStringArray(document, "knownIds");
+        var lastPublished = document.TryGetValue("lastPublished", out var publishedValue)
+            ? ParseDate(publishedValue)
+            : null;
+        var lastFetch = document.TryGetValue("lastFetchAt", out var fetchValue)
+            ? ParseDate(fetchValue)
+            : null;
+
+        return new KisaCursor(pendingDocuments, pendingMappings, knownIds, lastPublished, lastFetch);
+    }
+
+    private static IReadOnlyCollection<Guid> Distinct(IEnumerable<Guid>? values)
+        => values?.Distinct().ToArray() ?? EmptyGuids;
+
+    private static IReadOnlyCollection<Guid> ReadGuidArray(BsonDocument document, string field)
+    {
+        if (!document.TryGetValue(field, out var value) || value is not BsonArray array)
+        {
+            return EmptyGuids;
+        }
+
+        var items = new List<Guid>(array.Count);
+        foreach (var element in array)
+        {
+            if (Guid.TryParse(element?.ToString(), out var id))
+            {
+                items.Add(id);
+            }
+        }
+
+        return items;
+    }
+
+    private static IReadOnlyCollection<string> ReadStringArray(BsonDocument document, string field)
+    {
+        if (!document.TryGetValue(field, out var value) || value is not BsonArray array)
+        {
+            return EmptyStrings;
+        }
+
+        return array
+            .Select(element => element?.ToString() ?? string.Empty)
+            .Where(static s => !string.IsNullOrWhiteSpace(s))
+            .Distinct(StringComparer.OrdinalIgnoreCase)
+            .ToArray();
+    }
+
+    private static DateTimeOffset? ParseDate(BsonValue value)
+        => value.BsonType switch
+        {
+            BsonType.DateTime => DateTime.SpecifyKind(value.ToUniversalTime(), DateTimeKind.Utc),
+            BsonType.String when DateTimeOffset.TryParse(value.AsString, out var parsed) => parsed.ToUniversalTime(),
+            _ => null,
+        };
+}