progress.txt

## Codebase Patterns
- xUnit v3 (xunit.v3 1.1.0) requires explicit `using Xunit;` — not included in ImplicitUsings
- Test files go in mirrored folder structure: tests/TurdTracker.Tests/Services/ for service tests, tests/TurdTracker.Tests/Components/ for component tests
- bUnit component tests: use `BunitContext` with `JSRuntimeMode.Loose` and `AddMudServices()` for MudBlazor components
- Components using MudTextField with OnKeyDown (KeyInterceptorService) require `IAsyncDisposable` + `DisposeAsync()` instead of `IDisposable` in test class
- Registering services in bUnit: `_ctx.Services.AddSingleton<IService>(fake)` requires `using Microsoft.Extensions.DependencyInjection;`
- bUnit `EventCallback.Factory.Create<T>(this, handler)` requires `using Microsoft.AspNetCore.Components;`
- Build command: `DOTNET_CLI_USE_MSBUILD_SERVER=0 DOTNET_HOST_PATH=$(which dotnet) dotnet build` (required on macOS ARM64 to avoid task host error)
- `wasm-tools` workload must be installed (`dotnet workload install wasm-tools`) — without it, ComputeWasmBuildAssets fails with MSB4216
- Build with sandbox disabled for NuGet restore (network access required)
- Project source lives in `src/TurdTracker/`
- MudBlazor v9.2.0 configured with providers in MainLayout.razor
- Blazored.LocalStorage v4.5.0 (must specify version explicitly; latest search fails on .NET 10)
- Folder structure: Pages/, Components/, Models/, Services/ under src/TurdTracker/
- MudBlazor CSS/JS referenced in wwwroot/index.html
- Build from repo root: `DOTNET_CLI_USE_MSBUILD_SERVER=0 dotnet build src/TurdTracker/TurdTracker.csproj`
- DiaryService uses LocalStorage key "diary-entries"
- DI registration pattern: `builder.Services.AddScoped<IService, Service>()` in Program.cs
- `_Imports.razor` has global `@using TurdTracker.Services` — no per-page using needed
- Use `InvokeAsync(StateHasChanged)` when handling events from services (not on Blazor sync context)
- MergeEngine is static — call `MergeEngine.Merge(local, remote)` directly
- SyncService subscribes to DiaryService.OnDataChanged with 2-second debounce
- SyncService handles 412 (re-download + re-merge + retry up to 3x) and 401 (silent re-auth) automatically
- OnDataMerged event: SyncService fires this after ReplaceAllAsync when localChanged is true
- JS interop: `IJSRuntime.InvokeAsync("googleAuth.method", args)` — no `window.` prefix
- Google Drive API: files at `https://www.googleapis.com/drive/v3/files`, upload at `https://www.googleapis.com/upload/drive/v3/files`
- Hand-rolled fakes only — no Moq, NSubstitute, or any mocking framework
- Test project at tests/TurdTracker.Tests/ using xUnit + bUnit + FluentAssertions
- Fakes go in tests/TurdTracker.Tests/Fakes/ folder
- Use bUnit's built-in JSInterop for JS call verification (not hand-rolled IJSRuntime fake)
- FakeLocalStorageService backed by Dictionary<string, object> — uses ValueTask returns, nullable T? on GetItemAsync
- FakeDiaryService.SeedEntries() for test setup without triggering events or recording method calls
- FakeGoogleDriveService.CreateHttpException(statusCode) helper for creating typed HTTP exceptions
- FakeSyncService has extra OnDataMerged event (not yet on ISyncService interface)
- Test file naming: {ClassUnderTest}Tests.cs in mirrored folder structure
- Run tests: `dotnet test tests/TurdTracker.Tests/TurdTracker.Tests.csproj`
- bUnit JSInterop: use `JSRuntimeMode.Loose` for services that make many JS calls; verify with `_ctx.JSInterop.Invocations["identifier"]`
- bUnit v2.0.33-preview: use `BunitContext` (not `TestContext` which is ambiguous with xUnit v3's `Xunit.TestContext`)
- bUnit JSInterop `Setup<T>(identifier).SetResult(value)` for typed returns; void calls handled automatically in Loose mode
- GoogleDriveService: construct with `new GoogleDriveService(new HttpClient(fakeHandler), fakeAuthService)` — no DI needed
- DiaryEntry.Id is `Guid` (not string) — use `Guid.NewGuid()` directly
- FluentAssertions v8: method is `BeGreaterThanOrEqualTo` (not `BeGreaterOrEqualTo`)
- SyncService.Dispose() doesn't guard against double-dispose — use separate instances in Dispose tests to avoid class IDisposable conflicts
- For retry/error testing, use inline fakes with Queue<Exception> to control per-call behavior (e.g., ConfigurableDriveService)
- ISyncService now has `event Action? OnDataMerged` — pages subscribe in OnInitializedAsync, unsubscribe in Dispose
- bUnit NavigationManager: `_ctx.Services.GetRequiredService<NavigationManager>()` — no FakeNavigationManager in bUnit v2
- Page tests go in tests/TurdTracker.Tests/Pages/ — use IAsyncDisposable for MudBlazor components
- bUnit renders `<b>` with Blazor scope attributes (e.g. `<b b-xxx>`) — use CSS selector `.calendar-cell b` instead of `InnerHtml.Contains("<b>")`
- MudIconButton renders as `button.mud-icon-button` — select by CSS class, not by icon name in outerHtml
- Empty calendar cells have no innerHTML — use `string.IsNullOrWhiteSpace(c.InnerHtml)` to identify offset cells
- MudBlazor BarChart always renders SVG even when all data values are zero — `_frequencyData.Length == 0` never triggers because BuildFrequencyChart creates array with `days` elements; use `.All(d => d == 0)` check if you want to show empty state
- MudBlazor BarChart: select bars via `.mud-chart-bar` CSS class inside `svg.mud-chart-bar`; bar count equals data array length
- 30-day frequency chart labels only show every 5th day (`i % 5 == 0`) — don't rely on date labels for assertions; use bar count instead
- Stats page: MudChipSet `SelectedValueChanged` triggers `OnRangeChanged` — click `.mud-chip` elements to switch range in tests
- MudDatePicker/MudTimePicker require `MudPopoverProvider` in the render tree — render `_ctx.Render<MudPopoverProvider>()` before rendering the component under test
- MudIconButton: select Edit by `button.mud-icon-button.mud-primary-text`, Delete by `button.mud-icon-button.mud-error-text` — SVG icons have no text content
- FakeDialogService: `IDialogService.DialogInstanceAddedAsync` is `event Func<IDialogReference, Task>?`, `OnDialogCloseRequested` is `event Action<IDialogReference, DialogResult?>?` — not EventHandler types
- IDialogService.ShowAsync returns `Task<IDialogReference>` (not bare IDialogReference)
- bUnit JSInterop void call verification: use `SetupVoid("identifier")` + `VerifyInvoke("identifier")` — Loose mode handles the call but doesn't track it for verification without explicit Setup
- Reflection to set private fields for testing: `typeof(Component).GetField("_field", BindingFlags.NonPublic | BindingFlags.Instance)!.SetValue(instance, value)` — useful for MudDatePicker bound values
- MudBlazor Color.Default renders buttons WITHOUT a color-text CSS class — select by excluding known classes (mud-success-text, mud-error-text, etc.)
- MudTooltip v9: trigger `PointerEnter()` on `.mud-tooltip-root` to show tooltip popover content (not MouseOver)
- LayoutComponentBase tests: `_ctx.Render<Layout>(p => p.Add(x => x.Body, builder => builder.AddContent(0, "text")))`
- Theme toggle in appbar: filter buttons by `Closest(".mud-tooltip-root") == null` to distinguish from sync icon button

---

## 2026-03-25 21:28 - US-001
- Created xUnit test project at tests/TurdTracker.Tests/ with bUnit, FluentAssertions, Blazored.LocalStorage, MudBlazor
- Created GitHub Actions workflow at .github/workflows/test.yml triggering on PRs to main
- Project references src/TurdTracker/TurdTracker.csproj, builds and runs with zero tests
- **Learnings for future iterations:**
  - bUnit v2.0.33-preview is the version compatible with .NET 10
  - xunit.v3 v1.1.0 + xunit.runner.visualstudio v3.1.0 for xUnit v3 on .NET 10
  - FluentAssertions v8.3.0 works with .NET 10
  - Microsoft.NET.Test.Sdk v17.13.0 needed for test discovery
---

## 2026-03-25 22:00 - US-002
- Created 7 hand-rolled fakes in tests/TurdTracker.Tests/Fakes/:
  - FakeLocalStorageService: Dictionary-backed ILocalStorageService with all methods
  - FakeDiaryService: In-memory List<DiaryEntry>, tracks MethodCalls, has SeedEntries() helper
  - FakeGoogleAuthService: Configurable return values for all methods, tracks MethodCalls
  - FakeGoogleDriveService: Configurable results/exceptions, records upload details, has CreateHttpException() helper
  - FakeSyncService: Settable SyncStatus/LastError/LastSyncedUtc, invocable OnSyncStatusChanged/OnDataMerged events
  - FakeThemeService: In-memory dark mode state (defaults to true)
  - FakeHttpMessageHandler: URL-pattern and predicate-based response matching, tracks SentRequests
- Files changed: 7 new files in tests/TurdTracker.Tests/Fakes/
- **Learnings for future iterations:**
  - Blazored.LocalStorage 4.5.0 uses ValueTask returns and nullable T? on GetItemAsync
  - ILocalStorageService has ChangingEventArgs/ChangedEventArgs events — suppress CS0067 in fake
  - ISyncService doesn't have OnDataMerged yet — added as extra public event on FakeSyncService for future test stories
  - FakeDiaryService.SeedEntries() bypasses events/call-tracking for clean test setup
---

## 2026-03-25 22:35 - US-003
- Created 9 MergeEngine unit tests in tests/TurdTracker.Tests/Services/MergeEngineTests.cs
- Covers: empty merge, local-only, remote-only, local-wins, remote-wins, tie-break, tombstone purge (old/young), mixed scenario
- Files changed: 1 new file (MergeEngineTests.cs)
- **Learnings for future iterations:**
  - xUnit v3 requires explicit `using Xunit;` — ImplicitUsings does not include it
  - MergeEngine tie-break: equal LastModified → local wins but neither changed flag is set (code uses strict > for remoteChanged)
  - MergeEngine is static — test directly with `MergeEngine.Merge(local, remote)`, no DI needed
---

## 2026-03-25 23:10 - US-004
- Created 11 DiaryService unit tests in tests/TurdTracker.Tests/Services/DiaryServiceTests.cs
- Covers: AddAsync (store + LastModified + event), GetAllAsync (filters deleted), GetAllIncludingDeletedAsync, GetByIdAsync (found + not found), GetByDateAsync, UpdateAsync (update + event), UpdateAsync (non-existent ID no event), DeleteAsync (soft-delete + LastModified + event), ReplaceAllAsync (no event), BackfillLastModifiedIfNeeded (migration)
- Files changed: 1 new file (DiaryServiceTests.cs)
- **Learnings for future iterations:**
  - DiaryService uses real `new DiaryService(fakeLocalStorage)` — no DI container needed for unit tests
  - AddAsync sets IsDeleted entries into storage as-is — the filtering happens in GetAllAsync
  - BackfillLastModifiedIfNeeded only runs once per DiaryService instance (_hasMigrated flag) — seed data directly into FakeLocalStorageService to test migration
  - DiaryService storage key is "diary-entries" — use this to seed test data directly into FakeLocalStorageService
---

## 2026-03-25 - US-005
- Created 3 ThemeService unit tests in tests/TurdTracker.Tests/Services/ThemeServiceTests.cs
- Covers: GetIsDarkModeAsync default (true when no value), GetIsDarkModeAsync returns stored value, SetIsDarkModeAsync writes to localStorage
- Files changed: 1 new file (ThemeServiceTests.cs)
- **Learnings for future iterations:**
  - ThemeService storage key is "theme-dark-mode"
  - ThemeService defaults to dark mode (true) when no localStorage value exists
  - Simple services like ThemeService can be tested with just FakeLocalStorageService — no DI container needed
---

## 2026-03-25 - US-006
- Created 7 GoogleAuthService unit tests in tests/TurdTracker.Tests/Services/GoogleAuthServiceTests.cs
- Covers: InitializeAsync idempotency, SignInAsync (ensure init + JS call), SignOutAsync, IsSignedInAsync (ensure init + JS call), GetAccessTokenAsync, TrySilentSignInAsync (true when token, false when null)
- Files changed: 1 new file (GoogleAuthServiceTests.cs)
- **Learnings for future iterations:**
  - bUnit `TestContext` is ambiguous with xUnit v3's `Xunit.TestContext` — use `BunitContext` instead
  - bUnit JSInterop in strict mode requires explicit `SetupVoid` with argument matchers for each call; `JSRuntimeMode.Loose` is simpler for service-level tests
  - GoogleAuthService uses double-check locking pattern with SemaphoreSlim for initialization — tests verify idempotency
  - `Setup<string?>("identifier").SetResult((string?)null)` to test null return values
---

## 2026-03-25 - US-007
- Created 6 GoogleDriveService unit tests in tests/TurdTracker.Tests/Services/GoogleDriveServiceTests.cs
- Covers: FindSyncFileAsync (file exists → returns id/etag, no file → nulls), DownloadSyncFileAsync (deserializes SyncEnvelope), UploadSyncFileAsync (create new file when fileId null, update existing with If-Match etag, 412 conflict throws HttpRequestException)
- Files changed: 1 new file (GoogleDriveServiceTests.cs)
- **Learnings for future iterations:**
  - GoogleDriveService takes HttpClient + IGoogleAuthService via constructor — use FakeHttpMessageHandler with HttpClient for testing
  - FakeHttpMessageHandler URL pattern matching is substring-based — use distinctive URL fragments like "alt=media", "uploadType=multipart", "uploadType=media"
  - DiaryEntry.Id is `Guid` not `string` — use `Guid.NewGuid()` directly
  - EnsureSuccessStatusCode() throws HttpRequestException on non-2xx — no need to simulate specific exception types for 412/401 tests
- SyncService concurrency guard: if SyncStatus == Syncing, SyncAsync returns immediately — use a SlowFake with TaskCompletionSource to test this
- SyncService has no OnDataMerged event — PRD references it but it was never merged from archived feature branch
- For testing InitializeAsync with silent sign-in, need a custom fake that switches IsSignedIn to true after TrySilentSignInAsync (standard FakeGoogleAuthService can't model this state change)
---

## 2026-03-25 - US-008
- Created 9 SyncService unit tests in tests/TurdTracker.Tests/Services/SyncServiceTests.cs
- Covers: InitializeAsync (signed-in → sync, silent sign-in → sync, no session → NotSignedIn), SyncAsync (not signed in, happy path status transitions, concurrent call guard), merge results (LocalChanged → ReplaceAllAsync, RemoteChanged → UploadSyncFileAsync, OnDataChanged resubscription)
- Helper fakes: FakeGoogleAuthServiceWithSilentSignInSwitch (models sign-in state change), SlowFakeGoogleDriveService (TaskCompletionSource for concurrency testing)
- Files changed: 1 new file (SyncServiceTests.cs)
- **Learnings for future iterations:**
  - SyncService concurrency: SyncAsync returns immediately if SyncStatus == Syncing — use SlowFake with TaskCompletionSource to block first call while attempting second
  - SyncService InitializeAsync flow: checks IsSignedIn → HasPreviousSession → TrySilentSignIn, each branch needs its own test setup
  - OnDataMerged is referenced in PRD but not implemented in SyncService — archived feature branch was never merged
  - FakeGoogleAuthService can't model state transitions (e.g. IsSignedIn changing after TrySilentSignIn) — need custom inline fakes for these scenarios
---

## 2026-03-25 - US-009
- Created 10 SyncService error/retry/debounce tests in tests/TurdTracker.Tests/Services/SyncServiceTests.cs
- Covers: 412 retry (success + exhausted), 401 re-auth retry, network error revert, 500 error, general exception, LastError cleared, debounce cancellation, OnDataChanged re-subscription on ReplaceAll exception, Dispose cancels debounce
- Helper fakes: ConfigurableDriveService (queue-based upload exceptions), ThrowingDriveService (always throws), ThrowingOnReplaceDiaryService (throws on ReplaceAllAsync with toggle)
- Files changed: 1 modified file (SyncServiceTests.cs — added ~339 lines)
- **Learnings for future iterations:**
  - FluentAssertions v8: use `BeGreaterThanOrEqualTo` not `BeGreaterOrEqualTo`
  - SyncService.Dispose() does not null out _debounceCts after disposing — calling Dispose twice causes ObjectDisposedException; use separate SyncService instances in Dispose tests to avoid class-level IDisposable double-dispose
  - Debounce tests require ~3.5s wait (2s delay + margin) — acceptable for unit tests but slows suite
  - ConfigurableDriveService with Queue<Exception> for upload exceptions is the most flexible pattern for retry testing — dequeues one exception per call, succeeds when empty
  - HttpRequestException with null StatusCode (network error) is distinct from one with a status code — SyncService handles them differently
---

## 2026-03-25 - US-010
- Created 4 BristolScaleSelector bUnit component tests in tests/TurdTracker.Tests/Components/BristolScaleSelectorTests.cs
- Covers: renders all 7 Bristol type cards with names, selected card has bristol-card-selected class, clicking card invokes SelectedTypeChanged with correct value, no card selected when SelectedType=0
- Files changed: 1 new file (Components/BristolScaleSelectorTests.cs)
- **Learnings for future iterations:**
  - bUnit component tests need `BunitContext` with `JSRuntimeMode.Loose` and `AddMudServices()` for MudBlazor components
  - `EventCallback.Factory.Create<T>(receiver, handler)` requires `using Microsoft.AspNetCore.Components;` — not included by default
  - MudBlazor renders CSS classes on elements — use `.bristol-card` CSS selector to find cards, check `.ClassList` for selected state
  - Component tests go in tests/TurdTracker.Tests/Components/ mirroring the source structure
---

## 2026-03-26 - US-011
- Created 5 TagInput bUnit component tests in tests/TurdTracker.Tests/Components/TagInputTests.cs
- Covers: add tag via Enter key (TagsChanged callback), duplicate tag case-insensitive rejection, remove tag (TagsChanged callback), text field cleared after add, recent tags loaded from DiaryService (top 10, deduped, excluding current)
- Fixed compilation: added `using Microsoft.Extensions.DependencyInjection;` for `AddSingleton` on `BunitServiceProvider`
- Fixed disposal: MudTextField's OnKeyDown registers KeyInterceptorService (IAsyncDisposable) — switched from `IDisposable` to `IAsyncDisposable` with `DisposeAsync()`
- Files changed: 1 new file (Components/TagInputTests.cs)
- **Learnings for future iterations:**
  - `BunitServiceProvider` doesn't have `AddSingleton` directly — need `using Microsoft.Extensions.DependencyInjection;` for extension methods
  - Components with MudTextField + OnKeyDown register MudBlazor's `KeyInterceptorService` which only implements `IAsyncDisposable` — test class must use `IAsyncDisposable` + `DisposeAsync()` instead of `IDisposable`
  - bUnit `input.Change("value")` + `input.KeyDown(new KeyboardEventArgs { Key = "Enter" })` to simulate typing and pressing Enter
  - MudChip close buttons found via `.mud-chip button` selector
---

## 2026-03-26 - US-012
- Created 8 Home page bUnit component tests in tests/TurdTracker.Tests/Pages/HomeTests.cs
- Covers: empty entries message + Log Entry button, entry cards (Bristol type, timestamp, truncated notes at 80 chars, tags), clicking card navigates to /entry/{Id}, sync banner shown when not signed in and not dismissed, banner hidden when signed in, banner hidden when dismissed, OnDataMerged refreshes entries, Dispose unsubscribes OnDataMerged
- Added `event Action? OnDataMerged` to ISyncService interface and SyncService implementation (fires after ReplaceAllAsync when localChanged)
- Updated Home.razor to subscribe to OnDataMerged (refresh entries) and implement IDisposable (unsubscribe)
- Files changed: ISyncService.cs (added OnDataMerged), SyncService.cs (added OnDataMerged event + fire), Home.razor (subscribe/dispose), HomeTests.cs (new)
- **Learnings for future iterations:**
  - ISyncService now has `event Action? OnDataMerged` — all pages that refresh on sync should subscribe to this
  - bUnit NavigationManager: use `_ctx.Services.GetRequiredService<NavigationManager>()` (from Microsoft.AspNetCore.Components) — bUnit v2 doesn't expose FakeNavigationManager directly
  - Home.razor OnAfterRenderAsync runs after first render — use `cut.WaitForState()` in tests to wait for async state changes
  - Page test files go in tests/TurdTracker.Tests/Pages/ mirroring the source structure
  - `async void` event handlers with `InvokeAsync(StateHasChanged)` for cross-thread UI updates from service events
---

## 2026-03-26 - US-013
- Created 8 Calendar page bUnit component tests in tests/TurdTracker.Tests/Pages/CalendarTests.cs
- Covers: correct number of days for current month, Monday-start day-of-week offset, entry count badges on dates with entries, clicking date selects and shows entries, previous/next month navigation, empty selected date shows "No entries for this day", OnDataMerged refreshes entries, Dispose unsubscribes OnDataMerged
- Updated Calendar.razor to inject ISyncService, subscribe to OnDataMerged, implement IDisposable, and extracted RebuildEntriesByDate() helper
- Files changed: Calendar.razor (added ISyncService injection, OnDataMerged subscription, IDisposable), CalendarTests.cs (new)
- **Learnings for future iterations:**
  - bUnit renders `<b>` tags with Blazor scope attributes (e.g. `<b b-5a6vurbgxm>`) — never match `<b>` as literal string in InnerHtml; use CSS selectors like `.calendar-cell b` instead
  - MudIconButton renders as `button.mud-icon-button` — select by CSS class, don't look for icon name strings in outerHtml
  - Empty calendar offset cells have no innerHTML — use `string.IsNullOrWhiteSpace(c.InnerHtml)` to distinguish from day cells
  - `QuerySelectorAll("b")` on individual elements works for finding nested elements within a bUnit-found node
---

## 2026-03-26 - US-014
- Created 7 Stats page bUnit component tests in tests/TurdTracker.Tests/Pages/StatsTests.cs
- Covers: frequency chart daily counts for 7-day range, Bristol distribution tallies types 1-7, time of day chart buckets by hour, time range chip selection rebuilds frequency chart (7→30 bars), empty data renders without errors, OnDataMerged rebuilds charts, Dispose unsubscribes OnDataMerged
- Updated Stats.razor to inject ISyncService, subscribe to OnDataMerged, implement IDisposable with chart rebuild on sync
- Files changed: Stats.razor (added ISyncService injection, OnDataMerged subscription, IDisposable), StatsTests.cs (new)
- **Learnings for future iterations:**
  - MudBlazor BarChart always renders SVG even with all-zero data — `_frequencyData.Length == 0` never triggers; use `.All(d => d == 0)` for empty state detection
  - 30-day frequency chart labels show every 5th day only — don't assert on specific date labels; assert bar count instead (7 bars vs 30 bars)
  - MudBlazor BarChart bars selectable via `.mud-chart-bar` class inside `svg.mud-chart-bar` — bar count equals data array length
  - Stats page has 3 independent chart sections — each has its own empty-state check and SVG rendering
---

## 2026-03-26 - US-015
- Created 4 Log page bUnit component tests in tests/TurdTracker.Tests/Pages/LogTests.cs
- Covers: save with BristolType=0 shows validation error (no AddAsync call), save with valid data calls AddAsync with correct entry and navigates to /, entry timestamp combines date and time, cancel navigates to /
- Files changed: 1 new file (Pages/LogTests.cs)
- **Learnings for future iterations:**
  - MudDatePicker/MudTimePicker require `MudPopoverProvider` in the render tree — render `_ctx.Render<MudPopoverProvider>()` before the component under test
  - Log page uses default `DateTime.Today` and `DateTime.Now.TimeOfDay` — test timestamp by asserting date is today and time is non-zero
  - Bristol card selection: click `.bristol-card` elements by index (0-based, type = index + 1)
  - bUnit NavigationManager: assert `nav.Uri.Should().EndWith("/")` for home navigation (NavigateTo("") resolves to base URI with trailing slash)
---

## 2026-03-26 - US-016
- Created FakeDialogService in tests/TurdTracker.Tests/Fakes/ implementing IDialogService with configurable MessageBoxResult and MethodCalls tracking
- Created 6 EntryDetail page bUnit component tests in tests/TurdTracker.Tests/Pages/EntryDetailTests.cs
- Covers: loads/displays entry by ID (Bristol type, timestamp, notes, tags), entry not found error, edit button toggles edit form with pre-populated fields, save in edit mode calls UpdateAsync and exits edit mode, cancel in edit mode exits without saving, delete shows confirmation and calls DeleteAsync then navigates home
- Files changed: FakeDialogService.cs (new), EntryDetailTests.cs (new)
- **Learnings for future iterations:**
  - IDialogService has `event Func<IDialogReference, Task>? DialogInstanceAddedAsync` and `event Action<IDialogReference, DialogResult?>? OnDialogCloseRequested` — not standard EventHandler types
  - IDialogService.ShowAsync methods return `Task<IDialogReference>` not bare `IDialogReference`
  - MudIconButton rendered as SVG icons — no text content; select Edit by `button.mud-icon-button.mud-primary-text`, Delete by `button.mud-icon-button.mud-error-text`
  - FakeDialogService with configurable `MessageBoxResult` property is the cleanest way to test dialog confirmation flows
---

## 2026-03-26 - US-017
- Created 6 Settings page bUnit component tests in tests/TurdTracker.Tests/Pages/SettingsTests.cs
- Covers: sign-in calls SignInAsync and on success sets signed-in state + SyncAsync, sign-out calls SignOutAsync then SyncAsync, Sync Now calls SyncAsync, buttons disabled when SyncStatus==Syncing, sync status text/icon reflects current status (with OnSyncStatusChanged event updates), LastSyncedUtc displayed when available
- Files changed: 1 new file (Pages/SettingsTests.cs)
- **Learnings for future iterations:**
  - Settings page uses OnAfterRenderAsync (firstRender) to load state — bUnit triggers this automatically on Render
  - Sign-in button is `button.mud-button-filled`, sign-out/sync-now are `button.mud-button-outlined` — distinguish by TextContent
  - FakeSyncService.RaiseOnSyncStatusChanged() triggers InvokeAsync(StateHasChanged) in Settings page — use cut.WaitForState() to assert re-render
  - Settings page subscribes to OnSyncStatusChanged in OnAfterRenderAsync and unsubscribes in Dispose
---

## 2026-03-26 - US-018
- Created 6 Export page bUnit component tests in tests/TurdTracker.Tests/Pages/ExportTests.cs
- Updated Export.razor to inject ISyncService, subscribe to OnDataMerged, implement IDisposable with entry refresh on sync
- Covers: all entries shown when no date filter, start date filter excludes before, end date filter excludes after, both filters combined, export button calls window.print via JS interop, OnDataMerged refreshes entries
- Files changed: Export.razor (added ISyncService injection, OnDataMerged subscription, IDisposable), ExportTests.cs (new)
- **Learnings for future iterations:**
  - MudDatePicker private field values can be set via reflection for testing date filtering (typeof(Export).GetField("_startDate", BindingFlags.NonPublic | BindingFlags.Instance))
  - PrintExport has Task.Delay(100) — async tests need await Task.Delay(200) before verifying JS interop calls
  - bUnit JSInterop: use SetupVoid("window.print") + VerifyInvoke("window.print") for void JS calls — Loose mode auto-handles but doesn't track for verification
  - Export page filter is applied in PrintExport() and OnInitializedAsync() — clicking export button re-applies current filter settings
---

## 2026-03-26 - US-019
- Created 11 MainLayout bUnit component tests in tests/TurdTracker.Tests/Layout/MainLayoutTests.cs
- Added OnDataMerged subscription to MainLayout.razor — fires "Sync complete" snackbar when status is Synced or Idle
- Covers: sync icon CloudDone/Success when Synced, CloudSync/Inherit+spin when Syncing, CloudOff/Error when Error, CloudOff/Default when NotSignedIn, clicking error sync icon shows snackbar with LastError, OnDataMerged shows "Sync complete" snackbar (Synced + Idle), no snackbar when Syncing, theme toggle dark/light mode, tooltip shows status + LastSyncedUtc, tooltip shows "Not synced yet" when no last sync
- Files changed: MainLayout.razor (added OnDataMerged subscription/dispose + OnDataMerged handler with snackbar), MainLayoutTests.cs (new)
- **Learnings for future iterations:**
  - MudBlazor Color.Default renders icon buttons WITHOUT a color-text CSS class — select by excluding known color classes (mud-success-text, mud-error-text, mud-inherit-text, etc.)
  - MudTooltip v9 uses pointer events — trigger `PointerEnter()` on `.mud-tooltip-root` to show tooltip content in popover (not `MouseOver`)
  - Theme toggle button: distinguish from sync icon by filtering out buttons inside `.mud-tooltip-root` using `Closest(".mud-tooltip-root") == null`
  - LayoutComponentBase tests: render with `parameters.Add(p => p.Body, builder => builder.AddContent(0, "content"))` for body slot
  - MudSnackbar: `Snackbar.Add(message, severity)` renders message content in `MudSnackbarProvider` — assertable via `cut.Markup.Contains(message)`
---