Engineering

1. Architecture Overview

Nimbus is built on top of the .NET Framework 4.0 and WPF (Windows Presentation Foundation). It acts as a lightweight wrapper that translates XML declarative syntax into native WPF objects at runtime.

2. Execution Pipeline

When you run nimbus run App.xml, the following sequence occurs:

1. Parsing: XmlParser reads the XML file and separates UI, Logic, and Styles.
2. Initialization: WpfEngine initializes state variables and loads plugins.
3. UI Generation: WpfUI traverses the XML tree and recursively creates WPF controls (`Grid`, `Button`, etc.).
4. Event Wiring: The engine connects attributes like `onClick` to the internal event handler system.
5. Window Show: The main window is displayed using `Application.Run()`.

3. WpfEngine.cs

The central nervous system of the framework. It holds:

4. UI Generation (WpfUI.cs)

Nimbus does NOT use `XamlReader.Parse`. Instead, it manually constructs the visual tree for maximum control and custom component support.

Custom Component Logic

When the parser encounters a tag like <GlassCard>, it doesn't just create a generic control. It calls a specific generator method that assembles a complex visual tree (Border + BlurEffect + ContentPresenter).

// Pseudo-code of internal logic
if (tagName == "GlassCard") {
    var border = new Border();
    border.Effect = new BlurEffect();
    border.Background = new SolidColorBrush(...);
    // ... add children
    return border;
}

5. Hot Reload Logic

The engine uses a FileSystemWatcher to monitor the `App.xml` file.

When a change is detected:

• The file is re-read.
• The old Window content is cleared.
• The logic section is re-parsed (updating handlers).
• The UI is re-generated and injected into the existing Window instance.
• State variables are preserved (so you don't lose data).