test(07-08): add export and ViewModel unit tests

- UserAccessCsvExportServiceTests (5): summary section, data header, RFC 4180
  quote escaping, 7-column count, WriteSingleFileAsync multi-user output
- UserAccessHtmlExportServiceTests (7): DOCTYPE, stats cards, dual-view sections,
  access type badges, filterTable JS, toggleView JS, HTML entity encoding
- UserAccessAuditViewModelTests (8): AuditUsersAsync invocation, results population,
  summary properties computation, tenant switch reset, GlobalSitesChanged update,
  override guard, CanExport false/true states

SharepointToolbox.Tests/Services/Export/UserAccessCsvExportServiceTests.cs

@@ -0,0 +1,158 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services.Export;
+
+namespace SharepointToolbox.Tests.Services.Export;
+
+/// <summary>
+/// Unit tests for UserAccessCsvExportService (Phase 7 Plan 08).
+/// Verifies: summary section, column count, RFC 4180 escaping, per-user content.
+/// </summary>
+public class UserAccessCsvExportServiceTests
+{
+    // ── Helper factory ────────────────────────────────────────────────────────
+
+    private static UserAccessEntry MakeEntry(
+        string userDisplay = "Alice Smith",
+        string userLogin = "alice@contoso.com",
+        string siteUrl = "https://contoso.sharepoint.com",
+        string siteTitle = "Contoso",
+        string objectType = "List",
+        string objectTitle = "Docs",
+        string objectUrl = "https://contoso.sharepoint.com/Docs",
+        string permLevel = "Read",
+        AccessType accessType = AccessType.Direct,
+        string grantedThrough = "Direct Permissions",
+        bool isHighPrivilege = false,
+        bool isExternal = false) =>
+        new(userDisplay, userLogin, siteUrl, siteTitle, objectType, objectTitle, objectUrl,
+            permLevel, accessType, grantedThrough, isHighPrivilege, isExternal);
+
+    private static readonly UserAccessEntry DefaultEntry = MakeEntry();
+
+    // ── Test 1: BuildCsv includes summary section ─────────────────────────────
+
+    [Fact]
+    public void BuildCsv_includes_summary_section()
+    {
+        var svc = new UserAccessCsvExportService();
+        var csv = svc.BuildCsv("Alice Smith", "alice@contoso.com", new[] { DefaultEntry });
+
+        Assert.Contains("User Access Audit Report", csv);
+        Assert.Contains("Alice Smith", csv);
+        Assert.Contains("alice@contoso.com", csv);
+        Assert.Contains("Total Accesses", csv);
+        Assert.Contains("Sites", csv);
+    }
+
+    // ── Test 2: BuildCsv includes data header line ────────────────────────────
+
+    [Fact]
+    public void BuildCsv_includes_data_header()
+    {
+        var svc = new UserAccessCsvExportService();
+        var csv = svc.BuildCsv("Alice Smith", "alice@contoso.com", new[] { DefaultEntry });
+
+        Assert.Contains("Site", csv);
+        Assert.Contains("Object Type", csv);
+        Assert.Contains("Object", csv);
+        Assert.Contains("Permission Level", csv);
+        Assert.Contains("Access Type", csv);
+        Assert.Contains("Granted Through", csv);
+    }
+
+    // ── Test 3: BuildCsv escapes double quotes (RFC 4180) ─────────────────────
+
+    [Fact]
+    public void BuildCsv_escapes_quotes()
+    {
+        var entryWithQuotes = MakeEntry(objectTitle: "Document \"Template\" Library");
+        var svc = new UserAccessCsvExportService();
+        var csv = svc.BuildCsv("Alice", "alice@contoso.com", new[] { entryWithQuotes });
+
+        // RFC 4180: double quotes inside a quoted field are doubled
+        Assert.Contains("\"\"Template\"\"", csv);
+    }
+
+    // ── Test 4: BuildCsv data rows have correct column count ──────────────────
+
+    [Fact]
+    public void BuildCsv_correct_column_count()
+    {
+        var svc = new UserAccessCsvExportService();
+        var csv = svc.BuildCsv("Alice", "alice@contoso.com", new[] { DefaultEntry });
+
+        // Find the header row and count its quoted comma-separated fields
+        // Header is: "Site","Object Type","Object","URL","Permission Level","Access Type","Granted Through"
+        // That is 7 fields.
+        var lines = csv.Split('\n', StringSplitOptions.RemoveEmptyEntries);
+
+        // Find a data row (after the blank line separating summary from data)
+        // Data rows contain the entry content (not the header line itself)
+        // We want to count fields in the header row:
+        var headerLine = lines.FirstOrDefault(l => l.Contains("\"Site\",\"Object Type\""));
+        Assert.NotNull(headerLine);
+
+        // Count comma-separated quoted fields: split by "," boundary
+        var fields = CountCsvFields(headerLine!);
+        Assert.Equal(7, fields);
+    }
+
+    // ── Test 5: WriteSingleFileAsync includes entries for all users ───────────
+
+    [Fact]
+    public async Task WriteSingleFileAsync_includes_all_users()
+    {
+        var alice = MakeEntry(userDisplay: "Alice", userLogin: "alice@contoso.com");
+        var bob   = MakeEntry(userDisplay: "Bob",   userLogin: "bob@contoso.com");
+
+        var svc = new UserAccessCsvExportService();
+        var tmpFile = Path.GetTempFileName();
+        try
+        {
+            await svc.WriteSingleFileAsync(new[] { alice, bob }, tmpFile, CancellationToken.None);
+            var content = await File.ReadAllTextAsync(tmpFile);
+
+            Assert.Contains("alice@contoso.com", content);
+            Assert.Contains("bob@contoso.com", content);
+            Assert.Contains("Users Audited", content);
+        }
+        finally
+        {
+            File.Delete(tmpFile);
+        }
+    }
+
+    // ── Private helpers ───────────────────────────────────────────────────────
+
+    /// <summary>
+    /// Counts the number of comma-separated fields in a CSV line by stripping
+    /// surrounding quotes from each field.
+    /// </summary>
+    private static int CountCsvFields(string line)
+    {
+        // Simple RFC 4180 field counter — works for well-formed quoted fields
+        int count = 1;
+        bool inQuotes = false;
+        for (int i = 0; i < line.Length; i++)
+        {
+            char c = line[i];
+            if (c == '"')
+            {
+                if (inQuotes && i + 1 < line.Length && line[i + 1] == '"')
+                    i++; // skip escaped quote
+                else
+                    inQuotes = !inQuotes;
+            }
+            else if (c == ',' && !inQuotes)
+            {
+                count++;
+            }
+        }
+        return count;
+    }
+}

SharepointToolbox.Tests/Services/Export/UserAccessHtmlExportServiceTests.cs

@@ -0,0 +1,127 @@
+using System.Collections.Generic;
+using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services.Export;
+
+namespace SharepointToolbox.Tests.Services.Export;
+
+/// <summary>
+/// Unit tests for UserAccessHtmlExportService (Phase 7 Plan 08).
+/// Verifies: DOCTYPE, stats cards, dual-view sections, access type badges,
+/// filter script, toggle script, HTML entity encoding.
+/// </summary>
+public class UserAccessHtmlExportServiceTests
+{
+    // ── Helper factory ────────────────────────────────────────────────────────
+
+    private static UserAccessEntry MakeEntry(
+        string userDisplay = "Alice Smith",
+        string userLogin = "alice@contoso.com",
+        string siteUrl = "https://contoso.sharepoint.com",
+        string siteTitle = "Contoso",
+        string objectType = "List",
+        string objectTitle = "Docs",
+        string objectUrl = "https://contoso.sharepoint.com/Docs",
+        string permLevel = "Read",
+        AccessType accessType = AccessType.Direct,
+        string grantedThrough = "Direct Permissions",
+        bool isHighPrivilege = false,
+        bool isExternal = false) =>
+        new(userDisplay, userLogin, siteUrl, siteTitle, objectType, objectTitle, objectUrl,
+            permLevel, accessType, grantedThrough, isHighPrivilege, isExternal);
+
+    private static readonly UserAccessEntry DefaultEntry = MakeEntry();
+
+    // ── Test 1: BuildHtml contains DOCTYPE ───────────────────────────────────
+
+    [Fact]
+    public void BuildHtml_contains_doctype()
+    {
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { DefaultEntry });
+
+        Assert.StartsWith("<!DOCTYPE html>", html.TrimStart());
+    }
+
+    // ── Test 2: BuildHtml has stats cards ─────────────────────────────────────
+
+    [Fact]
+    public void BuildHtml_has_stats_cards()
+    {
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { DefaultEntry });
+
+        Assert.Contains("Total Accesses", html);
+        Assert.Contains("stat-card", html);
+    }
+
+    // ── Test 3: BuildHtml has both view sections ──────────────────────────────
+
+    [Fact]
+    public void BuildHtml_has_both_views()
+    {
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { DefaultEntry });
+
+        // By-user view
+        Assert.Contains("view-user", html);
+        // By-site view
+        Assert.Contains("view-site", html);
+    }
+
+    // ── Test 4: BuildHtml has access type badge CSS classes ───────────────────
+
+    [Fact]
+    public void BuildHtml_has_access_type_badges()
+    {
+        var entries = new List<UserAccessEntry>
+        {
+            MakeEntry(accessType: AccessType.Direct),
+            MakeEntry(userLogin: "bob@contoso.com", accessType: AccessType.Group),
+            MakeEntry(userLogin: "carol@contoso.com", accessType: AccessType.Inherited)
+        };
+
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(entries);
+
+        Assert.Contains("access-direct", html);
+        Assert.Contains("access-group", html);
+        Assert.Contains("access-inherited", html);
+    }
+
+    // ── Test 5: BuildHtml has filterTable JS function ─────────────────────────
+
+    [Fact]
+    public void BuildHtml_has_filter_script()
+    {
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { DefaultEntry });
+
+        Assert.Contains("filterTable", html);
+    }
+
+    // ── Test 6: BuildHtml has toggleView JS function ──────────────────────────
+
+    [Fact]
+    public void BuildHtml_has_toggle_script()
+    {
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { DefaultEntry });
+
+        Assert.Contains("toggleView", html);
+    }
+
+    // ── Test 7: BuildHtml encodes HTML entities ───────────────────────────────
+
+    [Fact]
+    public void BuildHtml_encodes_html_entities()
+    {
+        var entryWithScript = MakeEntry(objectTitle: "<script>alert('xss')</script>");
+        var svc = new UserAccessHtmlExportService();
+        var html = svc.BuildHtml(new[] { entryWithScript });
+
+        // Raw script tag must not appear verbatim
+        Assert.DoesNotContain("<script>alert", html);
+        // Encoded form must be present
+        Assert.Contains("&lt;script&gt;", html);
+    }
+}

SharepointToolbox.Tests/ViewModels/UserAccessAuditViewModelTests.cs

@@ -0,0 +1,246 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using CommunityToolkit.Mvvm.Messaging;
+using Microsoft.Extensions.Logging.Abstractions;
+using Moq;
+using SharepointToolbox.Core.Messages;
+using SharepointToolbox.Core.Models;
+using SharepointToolbox.Services;
+using SharepointToolbox.ViewModels;
+using SharepointToolbox.ViewModels.Tabs;
+
+namespace SharepointToolbox.Tests.ViewModels;
+
+/// <summary>
+/// Unit tests for UserAccessAuditViewModel (Phase 7 Plan 08).
+/// Verifies: AuditUsersAsync invocation, results population, summary properties,
+/// tenant switch reset, global sites message, override guard, CanExport state.
+/// </summary>
+public class UserAccessAuditViewModelTests
+{
+    // ── Reset messenger between tests ─────────────────────────────────────────
+
+    public UserAccessAuditViewModelTests()
+    {
+        WeakReferenceMessenger.Default.Reset();
+    }
+
+    // ── Helper factories ──────────────────────────────────────────────────────
+
+    private static UserAccessEntry MakeEntry(
+        string userLogin = "alice@contoso.com",
+        string siteUrl = "https://contoso.sharepoint.com",
+        bool isHighPrivilege = false) =>
+        new("Alice", userLogin, siteUrl, "Contoso", "List", "Docs",
+            siteUrl + "/Docs", "Read", AccessType.Direct, "Direct Permissions",
+            isHighPrivilege, false);
+
+    private static GraphUserResult MakeUser(
+        string display = "Alice Smith",
+        string upn = "alice@contoso.com") =>
+        new(display, upn, upn);
+
+    /// <summary>Creates a ViewModel wired with a mock IUserAccessAuditService.</summary>
+    private static (UserAccessAuditViewModel vm, Mock<IUserAccessAuditService> auditMock)
+        CreateViewModel(IReadOnlyList<UserAccessEntry>? auditResult = null)
+    {
+        var mockAudit = new Mock<IUserAccessAuditService>();
+        mockAudit
+            .Setup(s => s.AuditUsersAsync(
+                It.IsAny<ISessionManager>(),
+                It.IsAny<IReadOnlyList<string>>(),
+                It.IsAny<IReadOnlyList<SiteInfo>>(),
+                It.IsAny<ScanOptions>(),
+                It.IsAny<IProgress<OperationProgress>>(),
+                It.IsAny<CancellationToken>()))
+            .ReturnsAsync(auditResult ?? Array.Empty<UserAccessEntry>());
+
+        var mockGraph = new Mock<IGraphUserSearchService>();
+        var mockSession = new Mock<ISessionManager>();
+
+        var vm = new UserAccessAuditViewModel(
+            mockAudit.Object,
+            mockGraph.Object,
+            mockSession.Object,
+            NullLogger<FeatureViewModelBase>.Instance);
+
+        return (vm, mockAudit);
+    }
+
+    // ── Test 1: RunOperation calls AuditUsersAsync ────────────────────────────
+
+    [Fact]
+    public async Task RunOperation_calls_AuditUsersAsync()
+    {
+        var (vm, auditMock) = CreateViewModel();
+
+        vm.SelectedUsers.Add(MakeUser());
+        vm.SelectedSites.Add(new SiteInfo("https://contoso.sharepoint.com", "Contoso"));
+
+        await vm.TestRunOperationAsync(CancellationToken.None, new Progress<OperationProgress>());
+
+        auditMock.Verify(
+            s => s.AuditUsersAsync(
+                It.IsAny<ISessionManager>(),
+                It.IsAny<IReadOnlyList<string>>(),
+                It.IsAny<IReadOnlyList<SiteInfo>>(),
+                It.IsAny<ScanOptions>(),
+                It.IsAny<IProgress<OperationProgress>>(),
+                It.IsAny<CancellationToken>()),
+            Times.Once);
+    }
+
+    // ── Test 2: RunOperation populates Results ────────────────────────────────
+
+    [Fact]
+    public async Task RunOperation_populates_results()
+    {
+        var entries = new List<UserAccessEntry>
+        {
+            MakeEntry(),
+            MakeEntry(userLogin: "bob@contoso.com")
+        };
+
+        var (vm, _) = CreateViewModel(entries);
+
+        vm.SelectedUsers.Add(MakeUser());
+        vm.SelectedSites.Add(new SiteInfo("https://contoso.sharepoint.com", "Contoso"));
+
+        await vm.TestRunOperationAsync(CancellationToken.None, new Progress<OperationProgress>());
+
+        Assert.Equal(2, vm.Results.Count);
+    }
+
+    // ── Test 3: RunOperation updates summary properties ───────────────────────
+
+    [Fact]
+    public async Task RunOperation_updates_summary_properties()
+    {
+        var entries = new List<UserAccessEntry>
+        {
+            MakeEntry(userLogin: "alice@contoso.com", siteUrl: "https://contoso.sharepoint.com/sites/s1", isHighPrivilege: true),
+            MakeEntry(userLogin: "alice@contoso.com", siteUrl: "https://contoso.sharepoint.com/sites/s2", isHighPrivilege: false),
+            MakeEntry(userLogin: "bob@contoso.com",   siteUrl: "https://contoso.sharepoint.com/sites/s1", isHighPrivilege: true)
+        };
+
+        var (vm, _) = CreateViewModel(entries);
+
+        vm.SelectedUsers.Add(MakeUser());
+        vm.SelectedSites.Add(new SiteInfo("https://contoso.sharepoint.com", "Contoso"));
+
+        await vm.TestRunOperationAsync(CancellationToken.None, new Progress<OperationProgress>());
+
+        Assert.Equal(3, vm.TotalAccessCount);
+        Assert.Equal(2, vm.SitesCount);
+        Assert.Equal(2, vm.HighPrivilegeCount);
+    }
+
+    // ── Test 4: OnTenantSwitched resets state ─────────────────────────────────
+
+    [Fact]
+    public async Task OnTenantSwitched_resets_state()
+    {
+        var entries = new List<UserAccessEntry> { MakeEntry() };
+        var (vm, _) = CreateViewModel(entries);
+
+        // Populate state
+        vm.SelectedUsers.Add(MakeUser());
+        vm.SelectedSites.Add(new SiteInfo("https://contoso.sharepoint.com", "Contoso"));
+        await vm.TestRunOperationAsync(CancellationToken.None, new Progress<OperationProgress>());
+        Assert.NotEmpty(vm.Results);
+        Assert.NotEmpty(vm.SelectedUsers);
+
+        // Act: send TenantSwitchedMessage
+        var newProfile = new TenantProfile
+        {
+            Name = "NewTenant",
+            TenantUrl = "https://newtenant.sharepoint.com",
+            ClientId = "new-client-id"
+        };
+        WeakReferenceMessenger.Default.Send(new TenantSwitchedMessage(newProfile));
+
+        // Assert: state cleared
+        Assert.Empty(vm.Results);
+        Assert.Empty(vm.SelectedUsers);
+        Assert.Empty(vm.SelectedSites);
+        Assert.Empty(vm.FilterText);
+    }
+
+    // ── Test 5: GlobalSitesChanged updates SelectedSites ─────────────────────
+
+    [Fact]
+    public void OnGlobalSitesChanged_updates_selected_sites()
+    {
+        var (vm, _) = CreateViewModel();
+        var sites = new List<SiteInfo>
+        {
+            new("https://contoso.sharepoint.com/sites/hr", "HR"),
+            new("https://contoso.sharepoint.com/sites/finance", "Finance")
+        }.AsReadOnly();
+
+        WeakReferenceMessenger.Default.Send(new GlobalSitesChangedMessage(sites));
+
+        Assert.Equal(2, vm.SelectedSites.Count);
+        Assert.Equal("https://contoso.sharepoint.com/sites/hr", vm.SelectedSites[0].Url);
+    }
+
+    // ── Test 6: GlobalSitesChanged skipped when override active ──────────────
+
+    [Fact]
+    public void OnGlobalSitesChanged_skipped_when_override()
+    {
+        var (vm, _) = CreateViewModel();
+
+        // Add a local site and set the override flag via reflection
+        var localSite = new SiteInfo("https://contoso.sharepoint.com/sites/local", "Local");
+        vm.SelectedSites.Add(localSite);
+
+        var field = typeof(UserAccessAuditViewModel)
+            .GetField("_hasLocalSiteOverride",
+                System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+        field!.SetValue(vm, true);
+
+        // Act: send global sites message
+        var sites = new List<SiteInfo>
+        {
+            new("https://contoso.sharepoint.com/sites/global1", "Global1")
+        }.AsReadOnly();
+        WeakReferenceMessenger.Default.Send(new GlobalSitesChangedMessage(sites));
+
+        // Assert: SelectedSites unchanged (override prevented update)
+        Assert.Single(vm.SelectedSites);
+        Assert.Equal("https://contoso.sharepoint.com/sites/local", vm.SelectedSites[0].Url);
+    }
+
+    // ── Test 7: CanExport false when no results ───────────────────────────────
+
+    [Fact]
+    public void CanExport_false_when_no_results()
+    {
+        var (vm, _) = CreateViewModel();
+
+        // Results is empty by default
+        Assert.Empty(vm.Results);
+        Assert.False(vm.ExportCsvCommand.CanExecute(null));
+        Assert.False(vm.ExportHtmlCommand.CanExecute(null));
+    }
+
+    // ── Test 8: CanExport true when has results ───────────────────────────────
+
+    [Fact]
+    public async Task CanExport_true_when_has_results()
+    {
+        var entries = new List<UserAccessEntry> { MakeEntry() };
+        var (vm, _) = CreateViewModel(entries);
+
+        vm.SelectedUsers.Add(MakeUser());
+        vm.SelectedSites.Add(new SiteInfo("https://contoso.sharepoint.com", "Contoso"));
+
+        await vm.TestRunOperationAsync(CancellationToken.None, new Progress<OperationProgress>());
+
+        Assert.NotEmpty(vm.Results);
+        Assert.True(vm.ExportCsvCommand.CanExecute(null));
+        Assert.True(vm.ExportHtmlCommand.CanExecute(null));
+    }
+}