feat(ui): server-side streaming CSV export of Audit Log (#23 M7)

tests/ScadaLink.CentralUI.Tests/Pages/AuditLogPageExportUrlTests.cs

@@ -0,0 +1,77 @@
+using Microsoft.AspNetCore.WebUtilities;
+using ScadaLink.Commons.Types.Audit;
+using ScadaLink.Commons.Types.Enums;
+using AuditLogPage = ScadaLink.CentralUI.Components.Pages.Audit.AuditLogPage;
+
+namespace ScadaLink.CentralUI.Tests.Pages;
+
+/// <summary>
+/// Unit tests for <see cref="AuditLogPage.BuildExportUrl"/> (#23 M7-T14 /
+/// Bundle F). Builds the <c>?...</c> querystring the Export-CSV link points
+/// at; the same conversion is round-tripped on the server side by
+/// <see cref="ScadaLink.CentralUI.Audit.AuditExportEndpoints.ParseFilter"/>.
+/// These tests pin the no-filter base path + the round-trip back through
+/// <see cref="QueryHelpers.ParseQuery"/> so the link contract stays stable.
+/// </summary>
+public class AuditLogPageExportUrlTests
+{
+    [Fact]
+    public void BuildExportUrl_NullFilter_ReturnsBasePath()
+    {
+        var url = AuditLogPage.BuildExportUrl(null);
+        Assert.Equal("/api/centralui/audit/export", url);
+    }
+
+    [Fact]
+    public void BuildExportUrl_EmptyFilter_ReturnsBasePath()
+    {
+        // Defensive: a filter where every column is null should still render
+        // as the bare path — no trailing "?" so the URL stays clean.
+        var url = AuditLogPage.BuildExportUrl(new AuditLogQueryFilter());
+        Assert.Equal("/api/centralui/audit/export", url);
+    }
+
+    [Fact]
+    public void BuildExportUrl_AllFiltersSet_RoundTrips()
+    {
+        var corr = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+        var filter = new AuditLogQueryFilter(
+            Channel: AuditChannel.ApiOutbound,
+            Kind: AuditKind.ApiCall,
+            Status: AuditStatus.Failed,
+            SourceSiteId: "plant-a",
+            Target: "PaymentApi",
+            Actor: "apikey-1",
+            CorrelationId: corr,
+            FromUtc: new DateTime(2026, 5, 20, 0, 0, 0, DateTimeKind.Utc),
+            ToUtc: new DateTime(2026, 5, 20, 23, 59, 59, DateTimeKind.Utc));
+
+        var url = AuditLogPage.BuildExportUrl(filter);
+
+        Assert.StartsWith("/api/centralui/audit/export?", url);
+        var query = QueryHelpers.ParseQuery(new Uri("http://x" + url).Query);
+
+        Assert.Equal("ApiOutbound", query["channel"]);
+        Assert.Equal("ApiCall", query["kind"]);
+        Assert.Equal("Failed", query["status"]);
+        Assert.Equal("plant-a", query["site"]);
+        Assert.Equal("PaymentApi", query["target"]);
+        Assert.Equal("apikey-1", query["actor"]);
+        Assert.Equal(corr.ToString(), query["correlationId"]);
+        Assert.Equal("2026-05-20T00:00:00.0000000Z", query["from"]);
+        Assert.Equal("2026-05-20T23:59:59.0000000Z", query["to"]);
+    }
+
+    [Fact]
+    public void BuildExportUrl_OnlyChannelSet_OmitsOtherParams()
+    {
+        var filter = new AuditLogQueryFilter(Channel: AuditChannel.Notification);
+
+        var url = AuditLogPage.BuildExportUrl(filter);
+
+        Assert.StartsWith("/api/centralui/audit/export?", url);
+        var query = QueryHelpers.ParseQuery(new Uri("http://x" + url).Query);
+        Assert.Single(query);
+        Assert.Equal("Notification", query["channel"]);
+    }
+}