add README.md and fix minor issue

Reviewed-on: #1

README.md

@@ -1 +1,168 @@
 # GarandOS TUI
+
+## Overview
+
+GarandOS TUI is a terminal-based user interface tool designed to simplify the management of enabled modules in GarandOS NixOS configurations. It allows users to easily view and toggle boolean configuration options in both system and home module files through an intuitive interface.
+
+![GarandOS TUI Screenshot](./garandos-tui-presentation.png)
+
+## Features
+
+- Dual-pane interface for managing both system and home modules
+- Categorized view of configuration options
+- Simple keyboard navigation
+- Real-time toggle of boolean values in Nix configuration files
+- Automatic parsing and writing of Nix configuration syntax
+- Available via flake.nix
+
+## Installation
+
+### Using Nix
+
+#### As a Standalone Package
+
+```bash
+# Clone the repository
+git clone https://gitea.garandplg.com/GarandPLG/garandos-tui.git
+cd garandos-tui
+
+# Build using Nix
+nix build
+
+# Run the application
+nix run
+```
+
+### Building from Source
+
+```bash
+# Clone the repository
+git clone https://gitea.garandplg.com/GarandPLG/garandos-tui.git
+cd garandos-tui
+
+# Build with Cargo
+cargo build --release
+
+# Run the application
+cargo run -- --sf /path/to/system-modules.nix --hf /path/to/home-modules.nix
+```
+
+## Usage
+
+```bash
+garandos-tui --help
+
+garandos-tui --sf /path/to/system-modules.nix --hf /path/to/home-modules.nix
+```
+
+Where:
+- `--sf` specifies the path to your system modules file
+- `--hf` specifies the path to your home modules file
+
+In GarandOS, these files are located in:
+```
+~/garandos/hosts/<hostname>/system-modules.nix
+~/garandos/hosts/<hostname>/home-modules.nix
+```
+
+## Controls
+
+| Key                | Action                         |
+|--------------------|--------------------------------|
+| `↑` / `↓`          | Navigate options               |
+| `Enter` / `Space`  | Toggle selected option         |
+| `1` / `←`          | Switch to System modules       |
+| `2` / `→`          | Switch to Home modules         |
+| `q`                | Quit application               |
+
+## Interface
+
+The GarandOS TUI interface is divided into three main sections:
+
+1. **Header** - Shows the application title
+2. **Content Area** - Displays the configuration options, organized by categories
+3. **Footer** - Shows key bindings and the last action performed
+
+Options are displayed with checkboxes:
+- `☐` - Option is disabled (false)
+- `☑` - Option is enabled (true)
+
+## Configuration Format
+
+GarandOS TUI works with Nix configuration files that use a specific structure of boolean options. Options are organized by category using comments, for example:
+
+```nix
+_: {
+  /*
+  Container & Packaging
+  */
+  docker.enable = true; # Docker: container runtime and management
+  flatpak = {
+    enable = true; # Flatpak: universal packaging system for Linux
+    packages = {
+      sober.enable = false; # Roblox client
+      warehouse.enable = true; # Flatpak manager
+      flatseal.enable = true; # Flatpak permissions manager
+    };
+  };
+
+  /*
+  Gaming
+  */
+  gamemode.enable = true; # GameMode: optimizes system performance for gaming
+  gamescope.enable = false; # Gamescope: micro‑compositor for games
+  steam.enable = true; # Steam: platform for buying and playing games
+}
+```
+
+## NixOS Module Configuration
+
+When using GarandOS TUI as a NixOS module, the following options are available:
+
+| Option                | Description                                  | Default               |
+|-----------------------|----------------------------------------------|----------------------|
+| `enable`              | Enable the GarandOS TUI module               | `false`              |
+| `package`             | The GarandOS TUI package to use              | Default package      |
+| `systemModulesFilePath` | Path to system modules file                | `""`                 |
+| `homeModulesFilePath` | Path to home modules file                    | `""`                 |
+
+## Development
+
+### Development Environment
+
+A development shell is provided via Nix:
+
+```bash
+# Enter development shell
+nix develop
+
+# Available commands in the shell:
+# - nix build            - Build production version
+# - nix run              - Run production version
+# - nix build .#develop  - Build development version
+# - nix run .#develop    - Run development version
+```
+
+### Project Structure
+
+- `src/`
+  - `main.rs` - Application entry point
+  - `app.rs` - TUI application logic
+  - `cli.rs` - Command-line interface
+  - `nix.rs` - Nix file parsing and manipulation
+  - `lib.rs` - Module exports
+
+## License
+
+GarandOS TUI is licensed under the MIT License. See the [LICENSE](./LICENCE) file for details.
+
+## Authors
+
+- GarandPLG - [Gitea](https://gitea.garandplg.com/GarandPLG)
+
+## Acknowledgments
+
+- [ratatui](https://github.com/ratatui-org/ratatui) - Terminal UI library
+- [rnix](https://github.com/nix-community/rnix-parser) - Nix parser library
+- [clap](https://github.com/clap-rs/clap) - Command-line argument parser
+- [crossterm](https://github.com/crossterm-rs/crossterm) - Terminal manipulation library

src/app.rs

@@ -38,6 +38,8 @@ pub enum Event {
 impl App {
     pub fn run(&mut self, terminal: &mut DefaultTerminal, rx: Receiver<Event>) -> Result<()> {
         while !self.exit {
+            terminal.draw(|frame: &mut Frame<'_>| self.draw(frame))?;
+
             let event: Event = match rx.recv() {
                 Ok(ev) => ev,
                 Err(_) => break,
@@ -45,7 +47,6 @@ impl App {
             match event {
                 Event::Input(key_event) => self.handle_key_event(key_event)?,
             }
-            terminal.draw(|frame: &mut Frame<'_>| self.draw(frame))?;
         }
 
         Ok(())
@@ -252,7 +253,7 @@ impl Widget for &App {
                 Span::from("Use "),
                 Span::from("↑/↓".italic().green()),
                 Span::from(" to navigate, "),
-                Span::from("Enter/Space".bold().white()),
+                Span::from("Enter/Space".bold().yellow()),
                 Span::from(" to toggle, "),
                 Span::from("1/2 or ←/→".bold().blue()),
                 Span::from(" to switch file, "),