rblclass CLAUDE.md

CLAUDE.md

Project overview

This is a refactor of a legacy Outlook VBA macro into a modern Outlook COM add-in. It helps users quickly classify emails into folders across multiple .pst archives, with fast keyword search over the folder tree, attachment management, and send-time guards.

Stack and constraints

• Add-in technology: Outlook Shared COM Add-in — Extensibility.IDTExtensibility2 + Office.IRibbonExtensibility, registered into Outlook via HKCU keys under Software\Microsoft\Office\Outlook\Addins\. This is the classic, pre-VSTO Outlook add-in model. It supports PST access, offline use, and per-user install without admin rights on the classic Win32 Outlook client. VSTO is explicitly excluded for this project after the Office Developer Tools workload could not be set up on the dev machine.
• Target Outlook (deployment): classic Win32 Outlook, 32-bit, Microsoft 365 Apps for Enterprise on the Semi-Annual Enterprise Channel. NOT the "new Outlook". NO Exchange Online dependency.
• Dev Outlook: classic Win32 Outlook, 64-bit, Current channel, on Windows 11 ARM64 (Outlook runs as emulated x64 via Prism). The local dev machine differs from the deployment target in both architecture and channel. The same AnyCPU add-in binary must load on both. Final EDR and compatibility validation happens against a real 32-bit target workstation; the dev machine is for fast iteration only.
• Runtime: .NET Framework 4.8 for the add-in shell and the Outlook adapter. .NET Standard 2.0 for the business core.
• Language: C# 7.3 (.NET Framework 4.8 limit unless LangVersion is explicitly bumped, which we avoid).
• UI: WPF with a hand-rolled minimal MVVM (RBLclass.AddIn/Mvvm: ObservableObject + RelayCommand), hosted in Custom Task Panes via ICustomTaskPaneConsumer/ICTPFactory — the WPF view is bridged into a ComVisible WinForms host control through ElementHost. Ribbon via IRibbonExtensibility.GetCustomUI returning Ribbon XML (not the Ribbon Designer). CommunityToolkit.Mvvm is deliberately NOT used: its 8.x dependencies (System.Memory ≥ 4.5.5, System.Runtime.CompilerServices.Unsafe ≥ 6.0.0) float the SQLite facade assemblies above what SQLitePCLRaw was built against, and a COM host has no binding redirects, so it breaks the first SqliteConnection at runtime. Keep new AddIn dependencies dependency-light for the same reason.
• Storage: SQLite via Microsoft.Data.Sqlite, with FTS5 for full-text search. Database in %LocalAppData%\RBLclass.
• Logging: Serilog with a rolling file sink.
• Tests: xUnit, FluentAssertions, NSubstitute. Tests run against RBLclass.Core only; the Outlook adapter is excluded from CI tests.
• Packaging: per-user install via a signed installer that lays down the add-in DLL + dependencies under %LocalAppData%\RBLclass\ and writes the COM registration entries to HKCU. Phase 0 POC uses a PowerShell installer; Phase 1 promotes to an MSI built with the WiX Toolset, Authenticode-signed (both the DLL and the MSI) with an internal-PKI certificate carrying the Code Signing EKU (1.3.6.1.5.5.7.3.3). ClickOnce is not used — it is VSTO-specific in this scenario.
• Min Windows: Windows 10 1809.