Add comprehensive WPF to Avalonia conversion documentation

[Copilot]

Provides strategic planning and technical guidance for converting the 2,575-line MainWindow from WPF to Avalonia.

Documentation Suite (72KB)

AVALONIA_README.md (9KB)

Navigation hub with role-based quick starts, strategy summary, and timeline overview.

AVALONIA_CONVERSION_REPORT.md (25KB)

Part 1: Pre-Conversion Refactoring

• Extract 6 components from MainWindow (reduces 2,575 → 525 lines, 79.6% reduction)
• Component breakdown: Menu (450L), ModInfoPanel (300L), Tabs (1,200L), FilterBar (250L), Overlays (200L), StatusBar (150L)
• Week-by-week extraction plan with risk assessment

Part 2: Conversion Phases

• 6 phases over 20 weeks: Foundation → Simple → Complex → Tabs → Assembly → Platform
• Phase deliverables and critical challenges (DataGrid API differences, ModernWpfUI recreation, drag/drop)

Part 3: Code-Behind Strategy

• 14,232 lines analyzed: 44% unchanged (business logic, utilities), 56% requires conversion
• Section-by-section migration approach (UI interaction, WPF APIs, event handlers)

AVALONIA_TECHNICAL_GUIDE.md (25KB)

Side-by-side code examples covering:

• XAML syntax (Window declarations, resource dictionaries, namespace mappings)
• Control conversions (ItemsSource → Items, triggers → pseudo-classes)
• API replacements (DependencyProperty → StyledProperty, Mouse → Pointer events, file dialogs → StorageProvider)
• ToggleSwitch custom control implementation (no Avalonia equivalent for ModernWpfUI control)

// WPF
public static readonly DependencyProperty IsDataBackupInProgressProperty =
    DependencyProperty.Register(nameof(IsDataBackupInProgress), typeof(bool), typeof(MainWindow), new PropertyMetadata(false));

// Avalonia
public static readonly StyledProperty<bool> IsDataBackupInProgressProperty =
    AvaloniaProperty.Register<MainWindow, bool>(nameof(IsDataBackupInProgress), defaultValue: false);

AVALONIA_CONVERSION_CHECKLIST.md (13KB)

• Universal component conversion workflow
• Specific checklists for Menu, DataGrid, file dialogs, drag/drop, custom controls
• Platform testing matrix, common pitfalls, progress tracking template

Key Metrics

• MainWindow complexity: 2,575 lines XAML, 14,232 lines C#, 643 UI elements
• Timeline: 20 weeks with 4-week pre-conversion phase
• Code reuse: 6,300 lines (44%) unchanged, 8,000 lines (56%) needs work

Original prompt

Give me a full report on how to prepare for converting this entire project from wpf to avalonia. The report should focus on the large mainwindow xaml file and include:

What can be done before hand to split up the mainwindow file in order to make a conversion more viable?

What steps and in what order?

How to deal with the corresponding .cs file, what parts needs to be converted and what can stay

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