Instruction file imported from yuchung-chuang/PlotDigitizer (
.github/instructions/wpf.instructions.md). Copyright stays with the author.
PlotDigitizer.WPF conventions
This project is the composition root for the desktop app. App.xaml.cs builds the ServiceCollection, registers the WPF implementations of the Core service interfaces, configures the two keyed OCR services from appsettings.json, and adds the debug/file logging providers.
Keep logic out of this project
Business logic belongs in PlotDigitizer.Core so the CLI and Web frontends inherit it. This project should contain only WPF concerns: views, controls, value converters, validation rules, behaviours, and the service implementations that wrap WPF APIs (ClipboardService, FileDialogService, MessageBoxService, WindowService, AwaitTaskService). Code-behind should bind and delegate to a Core view model rather than compute results.
When you add a service that Core needs, define the interface in PlotDigitizer.Core/Services/Interfaces/ and register the WPF implementation in App.OnStartup.
PropertyChanged.Fody
PropertyChanged.Fody weaves INotifyPropertyChanged into properties at build time. Do not hand-write raise-on-set boilerplate for woven types, and do not add a static On<PropertyName>Changed method — Fody emits a build warning for that pattern.
Editor and selection state machines
Controls/Editor/States and Controls/SelectionBox are explicit state machines (EditorMode, EdittingState, SelectionBoxState). Add a new behaviour by adding a state class and its transitions rather than by adding conditionals to the control. Keep transition logic in the state classes so it stays reviewable.
Automation ids are a test contract
The FlaUI tests in PlotDigitizer.Core.Test locate elements by automation id, so ids are public API for tests. WPF exposes x:Name as the automation id automatically, and some elements set AutomationProperties.AutomationId explicitly.
Currently addressable ids include the PlotDigitizer main window; the navigation items LoadPageItem, AxisPageItem, RangePageItem, FilterPageItem, EditPageItem, DataPageItem; filePath; XLabel/YLabel; and the editor/toolbar buttons named with x:Name such as BrowseButton, PasteButton, UndoButton, PencilButton, EraserButton, RectButton, PolyButton, exportButton, NextPageButton, and PrevPageButton.
AxLimTextBox binds its automation id to its Label property, so the axis-limit inputs on RangePage are addressed as XMin, XMax, XLog, YMin, YMax, and YLog — not AxLim-prefixed names. The disabled IntegrationTest in UiTest.cs still uses the stale AxLimXMin-style ids and must be updated before it is re-enabled.
When you rename or remove an x:Name or Label that a UI test depends on, update the test in the same change. When you add a control that a UI test will need to reach, give it a stable x:Name.
Running the app
dotnet run --project .\PlotDigitizer.WPF\PlotDigitizer.WPF.csprojSetting "RunTest": true in appsettings.json makes App.OnStartup run a scripted smoke path after the main window opens. Leave it false in committed code.