app_window/

lib.rs

// SPDX-License-Identifier: MPL-2.0

/*!
<!-- The authoritative version of this document is the crate documentation in src/lib.rs. Edit there, then mirror the changes here. -->

# app_window

A cross-platform window crate with an async-first API.

![logo](https://github.com/drewcrawford/app_window/raw/main/art/logo.png)

`app_window` creates windows and rendering surfaces on Windows, macOS, Linux, and
WebAssembly. It is deliberately small: you get a window, a surface that plugs into
anything that consumes `raw-window-handle` (wgpu, OpenGL, Vulkan), cross-platform
keyboard and mouse input, and a main-thread executor. You bring the renderer and
the rest of your application.

The crate exists because platforms disagree about threads. macOS insists UI runs
on the main thread. Wayland compositors behave best when rendering stays *off*
the main thread. In the browser, the main thread is the event loop and blocking
it is fatal. Most windowing libraries hand this problem to you: they own an event
loop, call you back on a thread of their choosing, and your architecture bends
around theirs. `app_window` inverts that. It takes ownership of the main thread
once, at startup, and from then on every API is an async function you can call
from any thread. The crate routes each call to whatever thread the current
platform requires; you write straight-line code.

# What it is — and isn't

`app_window` provides:

- **Windows** — created from any thread; a window closes when its `Window` value drops
- **Surfaces** — implement the `raw-window-handle` traits, so wgpu, glutin, ash, and friends plug in directly
- **Input** — keyboard (physical keys, layout-independent) and mouse, unified across platforms
- **Main-thread dispatch** — `application::on_main_thread`, a main-thread executor integrated with the native event loop, and `MainThreadCell` for values pinned to that thread

It is **not** a GUI toolkit. There are no widgets, no layout engine, no text
rendering. If you want buttons out of the box, look at egui, iced, or Slint
instead. The intended pairing is `app_window` + wgpu + your own rendering code —
a game, a visualization, a custom-drawn UI.

# Where it fits in the ecosystem

```text
┌─────────────────────────────────────────────────┐
│                your application                 │
├─────────────────────────────────────────────────┤
│     wgpu / OpenGL / Vulkan / your renderer      │
│            (via raw-window-handle)              │
├─────────────────────────────────────────────────┤
│    app_window: window · surface · input ·       │
│             main-thread executor                │
├──────────┬────────────┬───────────┬─────────────┤
│  Win32   │   AppKit   │  Wayland  │   Canvas    │
│(Windows) │(macOS, via │  (Linux)  │   (Web)     │
│          │   Swift)   │           │             │
└──────────┴────────────┴───────────┴─────────────┘
```

Three integration points matter:

- **raw-window-handle** is the Rust ecosystem's standard interface between
  windowing and graphics. `Surface` implements it, so any renderer that consumes
  it works without `app_window` knowing anything about it: wgpu (recommended; see
  `examples/gpu.rs`), OpenGL via glutin, Vulkan via ash, Metal via metal-rs,
  DirectX via windows-rs.
- **Async runtimes.** The crate is executor-agnostic through
  [`some_executor`](https://sealedabstract.com/code/some_executor). At startup it
  installs its main-thread executor via those traits, and it interoperates with
  any runtime that speaks the same interface. There is no tokio dependency and no
  runtime lock-in.
- **WebAssembly.** The browser backend is built on
  [`wasm_lite`](https://github.com/drewcrawford/wasm_lite) — hand-written DOM
  bindings — rather than web-sys/wasm-bindgen, and targets shared-memory
  threading (atomics + bulk memory), so the same multithreaded architecture you
  use natively runs in the browser. wgpu still uses wasm-bindgen internally; a
  one-line patch (see the WASM + wgpu section below) lets the two coexist.

The macOS backend is written in Swift and doubles as a Swift package
(`SwiftAppWindow/`), so the same windowing layer is callable from Swift.

# Alternatives

The Rust windowing space has a clear incumbent and several specialists. What
follows is an honest comparison; `app_window` is not the right choice for every
project.

**[winit](https://crates.io/crates/winit)** is the de facto standard and the
default answer for most projects — Bevy, eframe, and iced all sit on top of it.
It supports a much larger platform matrix than `app_window`: X11 as well as
Wayland, Android, iOS. The trade is architectural: winit owns your event loop and
calls back into your `ApplicationHandler`, and each platform's thread-affinity
rules — what must happen on the main thread, what must not — are yours to know
and manage. Choose winit when you need its platform breadth or its ecosystem;
choose `app_window` when you'd rather write async code and let the library carry
the threading rules.

**[tao](https://crates.io/crates/tao)** is Tauri's fork of winit, extended with
app menus and a system tray, and GTK-backed on Linux. It's the natural choice if
you're building around a webview.

**[sdl2](https://crates.io/crates/sdl2)** / **[sdl3](https://crates.io/crates/sdl3)**
bind the C SDL library: windowing plus audio, game controllers, haptics, and
more, with decades of portability behind it. You accept a C dependency and a
polling-style API. A good fit for games that want batteries included.

**[glfw](https://crates.io/crates/glfw)** binds the C GLFW library: minimal,
OpenGL-oriented, desktop-focused.

**[miniquad](https://crates.io/crates/miniquad)** (and macroquad above it)
bundles windowing with its own graphics abstraction and produces very small wasm
builds — but you use its rendering API rather than wgpu.

**[minifb](https://crates.io/crates/minifb)** puts a CPU framebuffer in a
window. If "give me pixels" is the whole requirement, it's the simplest thing
that works.

**egui/eframe, iced, Slint, gtk4-rs, fltk-rs** are toolkits, not windowing
crates: they bundle windowing (usually winit) and give you widgets. Compare them
against `app_window` plus your renderer, not against `app_window` alone.

| Crate      | API model                    | Linux         | Mobile | Web                         | Scope                          |
|------------|------------------------------|---------------|--------|-----------------------------|--------------------------------|
| app_window | async, call from any thread  | Wayland       | —      | wasm, shared-memory threads | window + surface + input       |
| winit      | event loop, callbacks        | Wayland + X11 | yes    | wasm-bindgen                | window + surface + input       |
| tao        | event loop, callbacks        | GTK           | yes    | —                           | winit fork + menus/tray        |
| sdl2/sdl3  | C library, polling           | Wayland + X11 | yes    | emscripten                  | windowing + audio + controllers|
| glfw       | C library, polling           | Wayland + X11 | —      | —                           | OpenGL-focused windowing       |
| miniquad   | event callbacks              | X11 + Wayland | yes    | tiny wasm                   | window + built-in renderer     |

In short: reach for `app_window` for the async API, the unified threading model,
first-class shared-memory wasm, and a native Wayland backend. Pass on it if you
need X11 or mobile, if a framework you use requires winit, or if you want the
largest possible community behind your windowing layer.

# Quick Start

First, initialize the application from your main function:

```no_run
# // no_run because: application::main() must be called from the actual main thread, which is not available in doctests
use app_window::application;
fn main() {
    application::main(|| {
        // Your application code here
        async fn run() {
            // Create windows, handle events, etc.
        }
        futures::executor::block_on(run());
    });
}
#[allow(clippy::needless_doctest_main)]
```

Then create windows from any async context:

```
# async fn example() {
use app_window::{window::Window, coordinates::{Position, Size}};

// Create a window at a specific position
let window = Window::new(
    Position::new(100.0, 100.0),
    Size::new(800.0, 600.0),
    "My Application".to_string()
).await;

// The window stays open as long as the Window instance exists
// When dropped, the window automatically closes
# }
```

Windows are tied to their Rust value: drop the `Window` and the window closes.
There is no separate close/destroy step to forget.

# Threading Model

Every public API is async and callable from any thread; the crate dispatches to
the right place per platform:

```
# async fn example() {
use app_window::window::Window;

// This works on any thread, on any platform
let window = Window::default().await;

// Platform-specific threading is handled internally:
// - On macOS: dispatched to main thread
// - On Windows/Linux: may run on current thread
// - On Web: runs on the single thread
# }
```

Under the hood:

- **macOS**: All UI operations dispatched to main thread via GCD
- **Windows**: UI operations can run on any thread
- **Linux (Wayland)**: Compositor-dependent, handled per-connection
- **WebAssembly**: Single-threaded, operations run directly

When you need the main thread explicitly, ask for it:

```
# async fn example() {
use app_window::application;

// This works everywhere, regardless of platform requirements
let result = application::on_main_thread("my_task".to_string(), || {
    // Guaranteed to run on main thread
    42
}).await;
# }
```

## wgpu threading strategies

Platforms also disagree about which thread may drive the GPU. The crate encodes
those rules in two constants so your rendering setup can branch on them instead
of hardcoding per-OS knowledge:

- `WGPU_STRATEGY` — where general wgpu work should happen
- `WGPU_SURFACE_STRATEGY` — where surfaces may be created and configured
  (notably: macOS is `Relaxed` for general wgpu use but `MainThread` for
  surface creation)

```
use app_window::{WGPU_STRATEGY, WGPUStrategy};

match WGPU_STRATEGY {
    WGPUStrategy::MainThread => {
        // Platform requires wgpu on main thread (Web, some macOS configs)
    }
    WGPUStrategy::NotMainThread => {
        // Platform requires wgpu NOT on main thread (Linux/Wayland)
    }
    WGPUStrategy::Relaxed => {
        // Platform allows wgpu on any thread (Windows, most macOS)
    }
    _ => {
        // Future-proof: handle any new strategies
        // Default to the safest option
    }
}
```

# Examples

## Creating a fullscreen window

```
# async fn example() {
use app_window::window::Window;

match Window::fullscreen("My Game".to_string()).await {
    Ok(mut window) => {
        // Fullscreen window created
        let surface = window.surface().await;
        // Set up rendering...
    }
    Err(e) => eprintln!("Failed to create fullscreen window: {:?}", e),
}
# }
```

## Handling window resize

```
# async fn example() {
use app_window::{window::Window, coordinates::Size};

let mut window = Window::default().await;
let mut surface = window.surface().await;

// Register a callback for size changes
surface.size_update(|new_size: Size| {
    println!("Window resized to {}x{}", new_size.width(), new_size.height());
    // Update your rendering viewport...
});
# }
```

## Input handling

Keyboard input reports physical keys — the key labeled W on a QWERTY board,
regardless of active layout. That makes it a fit for game controls and
shortcuts, not for text entry. Mappings cover alphanumeric and symbol keys,
F1–F24, the numeric keypad, media and navigation keys, modifiers, and
international layouts (JIS, ISO).

```
# async fn example() {
use app_window::input::{
    keyboard::{Keyboard, key::KeyboardKey},
    mouse::{Mouse, MOUSE_BUTTON_LEFT}
};

// Create input handlers
let keyboard = Keyboard::coalesced().await;
let mut mouse = Mouse::coalesced().await;

if keyboard.is_pressed(KeyboardKey::Space) {
    println!("Space key is pressed!");
}

if keyboard.is_pressed(KeyboardKey::W) {
    println!("W key pressed - move forward!");
}

// Check mouse state
if let Some(pos) = mouse.window_pos() {
    println!("Mouse at ({}, {})", pos.pos_x(), pos.pos_y());
}

if mouse.button_state(MOUSE_BUTTON_LEFT) {
    println!("Left mouse button is pressed!");
}

// Get scroll delta (clears after reading)
let (scroll_x, scroll_y) = mouse.load_clear_scroll_delta();
if scroll_y != 0.0 {
    println!("Scrolled vertically by {}", scroll_y);
}
# }
```

## Integrating with wgpu

For wgpu integration, use the platform-specific strategy:

```no_run
# // no_run because: full wgpu example requires graphics setup beyond scope of doctest
# async fn example() -> Result<(), Box<dyn std::error::Error>> {
use app_window::{window::Window, application, WGPU_STRATEGY, WGPUStrategy};

let mut window = Window::default().await;
let surface = window.surface().await;

// Use the appropriate strategy for your platform
match WGPU_STRATEGY {
    WGPUStrategy::MainThread => {
        application::on_main_thread("wgpu_init".to_string(), move || {
            // Create wgpu instance and surface on main thread
        }).await;
    }
    WGPUStrategy::NotMainThread => {
        // Create wgpu instance and surface on worker thread
    }
    WGPUStrategy::Relaxed => {
        // Create wgpu instance and surface on any thread
    }
    _ => {
        // Handle future strategies
    }
}
# Ok(())
# }
```

See `examples/gpu.rs` for a complete wgpu integration example.

## WASM + wgpu

`wgpu` uses the wasm-bindgen API on WebAssembly, while this crate's browser
backend uses `wasm_lite`. To build an application that combines both, add the
wasm_lite compatibility patch to the application manifest:

```toml
[patch.crates-io]
wasm-bindgen = { git = "https://github.com/drewcrawford/wasm_lite", rev = "f47bf4178d666e83017abe056f07bb20d33c14cd" }
```

The patch belongs in the final application's `Cargo.toml`; Cargo does not
inherit patches from dependencies. Patch only `wasm-bindgen`—do not replace
`wasm_lite` or `wasm_lite_std` with git or path dependencies, because the
compatibility crate now resolves those released runtimes from crates.io. The
application also needs the released `wasm_lite_cli` runner and the shared-memory
WASM linker settings shown in this repository's `.cargo/config.toml`.

# Platform Support

| Platform | Backend | Status | Notes |
|----------|---------|--------|-------|
| Windows  | Win32 API | ✅ Stable | Full async support, relaxed threading |
| macOS    | AppKit via Swift | ✅ Stable | Main thread UI, Swift interop |
| Linux    | Wayland | ✅ Stable | Client-side decorations, compositor-dependent |
| Web      | Canvas API | ✅ Stable | Requires atomics & bulk memory features |

Linux support is Wayland-only; there is no X11 backend. Requires Rust 1.95+
(2024 edition).

# Cargo Features

The default feature set is empty; everything above works with no features
enabled. The optional extras are diagnostic:

- `exfiltrate` — keeps a bounded registry of the windows this process has
  created and exposes it, along with main-thread state, through the
  `exfiltrate` crate's `snapshot` command for inspecting live processes. Off by
  default because it costs a lock and a record per window.
- `logwise-diagnostic`, `logwise-forensic`, `logwise-performance` — enable
  progressively more detailed logging through the `logwise` facade. Operational
  failures — a window that won't open, a frozen main thread — are always
  compiled in and need no feature.

# Development

`scripts/check_all` runs the full gate: formatting, native and wasm checks,
clippy, tests, and docs, with warnings as errors. Per-target variants live in
`scripts/native/` and `scripts/wasm32/`; wasm tests run under the `wasm_lite`
runner on nightly.

## License

This project is licensed under the Mozilla Public License 2.0 (MPL-2.0).

*/

/// Window creation and management.
///
/// This module provides the [`window::Window`] type for creating and managing windows
/// across different platforms. Windows can be created from any thread after the
/// application has been initialized.
///
/// # Example
/// ```
/// # async fn example() {
/// use app_window::{window::Window, coordinates::{Position, Size}};
///
/// // Create a window with specific position and size
/// let window = Window::new(
///     Position::new(100.0, 100.0),
///     Size::new(800.0, 600.0),
///     "My Application".to_string()
/// ).await;
/// # }
/// ```
pub mod window;

/// Application lifecycle and main thread management.
///
/// This module provides the entry point for app_window applications and utilities
/// for executing code on the main thread. The [`application::main`] function must
/// be called once from the first thread to initialize the platform event loop.
///
/// Key functions:
/// - [`application::main`] - Initialize the application and event loop
/// - [`application::on_main_thread`] - Execute async code on the main thread
/// - [`application::submit_to_main_thread`] - Fire-and-forget main thread tasks
///
/// Most functions in this module will panic if [`application::main`] hasn't been called yet.
/// [`application::main`] is called at the start of your program.
///
/// # Example
/// ```no_run
/// # // no_run because: application::main() must be called from the actual main thread, which is not available in doctests
/// use app_window::application;
///
/// fn main() {
///     application::main(|| {
///         // Application code here
///     });
/// }
/// ```
pub mod application;

mod sys;

/// Coordinate types for window positioning and sizing.
///
/// This module provides [`coordinates::Position`] and [`coordinates::Size`] types
/// for working with window coordinates. All values are in logical pixels, which
/// may differ from physical pixels on high-DPI displays.
///
/// # Example
/// ```
/// use app_window::coordinates::{Position, Size};
///
/// let pos = Position::new(100.0, 200.0);
/// assert_eq!(pos.x(), 100.0);
/// assert_eq!(pos.y(), 200.0);
///
/// let size = Size::new(800.0, 600.0);
/// assert_eq!(size.width(), 800.0);
/// assert_eq!(size.height(), 600.0);
/// ```
pub mod coordinates;

/// Rendering surface abstraction.
///
/// This module provides the [`surface::Surface`] type, which represents a drawable
/// area within a window. Surfaces integrate with graphics APIs like wgpu through
/// the `raw-window-handle` trait implementations.
///
/// # Example
/// ```
/// # async fn example() {
/// # use app_window::{application, window::Window};
/// let mut window = Window::default().await;
/// let surface = window.surface().await;
///
/// // Get size and scale factor
/// let (size, scale) = surface.size_scale().await;
///
/// // Get handles for graphics API integration
/// let window_handle = surface.window_handle();
/// let display_handle = surface.display_handle();
/// # }
/// ```
pub mod surface;

/// Cross-platform mouse and keyboard input handling.
///
/// This module provides keyboard and mouse input functionality that integrates
/// with app_window. It handles platform-specific input events and provides
/// a unified API across Windows, macOS, Linux, and WebAssembly.
///
/// # Keyboard Input
///
/// The keyboard module uses physical key mappings rather than logical characters.
/// This means [`input::keyboard::key::KeyboardKey`] represents actual physical keys on the
/// keyboard (e.g., the key labeled 'A' on QWERTY), independent of keyboard layout.
/// This approach is ideal for game controls and shortcuts but not for text input.
///
/// Comprehensive key mappings include:
/// - Standard alphanumeric keys (A-Z, 0-9) and symbol keys (brackets, quotes, etc.)
/// - Function keys (F1-F24) with extensive coverage up to F24
/// - Numeric keypad keys with full support (0-9, operators, decimal, Enter, Clear/Num Lock)
/// - Media control keys (Play/Pause, Stop, Volume Up/Down, Mute, Previous/Next Track)
/// - Navigation keys (arrows, Home, End, Page Up/Down, Insert, Delete)
/// - Modifier keys (Shift, Control, Option/Alt, Command/Windows, Function)
/// - International keyboard layouts (Japanese JIS keys: Yen, Kana, Eisu, Convert; ISO Section key)
/// - Browser and application launcher keys
/// - Editing keys (Undo, Copy, Cut, Paste, Find, Select)
///
/// On macOS, debug windows are available via `input::keyboard::macos::debug_window_show()`
/// and `input::keyboard::macos::debug_window_hide()` to inspect real-time raw keyboard events,
/// useful for debugging keyboard handling and understanding platform-specific key codes.
///
/// # Example
/// ```
/// # async fn example() {
/// use app_window::input::{keyboard::Keyboard, mouse::Mouse};
///
/// // Create input handlers
/// let keyboard = Keyboard::coalesced().await;
/// let mouse = Mouse::coalesced().await;
/// # }
/// ```
pub mod input;

/// Main thread executor for async operations.
///
/// This module provides utilities for running futures on the main thread, which is
/// required for UI operations on many platforms. The executor integrates with the
/// native event loop to process both async tasks and platform events.
///
/// # Example
/// ```
/// #[cfg(target_arch = "wasm32")] {
/// }
/// use app_window::test_support::doctest_main;
/// use some_executor::task::{Configuration, Task};
///
/// doctest_main(|| {
///     Task::without_notifications(
///         "doctest".to_string(),
///         Configuration::default(),
///         async {
///             use app_window::executor;
///
///             async fn my_async_function() -> i32 { 42 }
///
///             // Run an async function on the main thread
///             let result = executor::on_main_thread_async(
///                 "ex".to_owned(),
///                 my_async_function()
///             ).await;
///             assert_eq!(result, 42);
///         },
///     ).spawn_static_current();
/// });
/// ```
pub mod executor;

/// Integration with the `some_executor` crate.
///
/// This module provides [`some_executor::MainThreadExecutor`], which implements
/// the `SomeExecutor` and `SomeLocalExecutor` traits from the `some_executor` crate.
/// This allows the main thread executor to be used with any library that supports
/// the `some_executor` abstraction.
///
/// When [`application::main`] is called, a `MainThreadExecutor` is automatically
/// installed as the thread-local and thread-static executor, making it available
/// to any code using `some_executor`'s convenience functions.
pub mod some_executor;

/// Thread-safe cell for main-thread-only values.
///
/// `MainThreadCell<T>` is a thread-safe container that allows `T` to be shared across threads
/// while ensuring all access to the inner value happens on the main thread.
/// This is useful for platform-specific resources that have main-thread requirements.
///
/// # Example
/// ```
/// # async fn example() {
/// use app_window::main_thread_cell::MainThreadCell;
///
/// // Create a cell on the main thread. From another thread, use
/// // MainThreadCell::new_on_main_thread instead.
/// let cell = MainThreadCell::new(42);
///
/// // Access from main thread directly
/// if app_window::application::is_main_thread() {
///     let guard = cell.lock();
///     println!("Value: {}", *guard);
/// }
///
/// // Access from any thread via async dispatch
/// let result = cell.with(|value| {
///     // This runs on the main thread
///     *value * 2
/// }).await;
/// assert_eq!(result, 84);
/// # }
/// ```
pub mod main_thread_cell;

/// Main-thread liveness accounting, always compiled in.
pub mod instrument;

/// A bounded record of this process's windows.
#[cfg(feature = "exfiltrate")]
pub mod registry;

/// Window and main-thread state as exfiltrate `snapshot` subsystems.
#[cfg(feature = "exfiltrate")]
pub mod exfiltrate_provider;

/// Test support utilities for working with the main thread.
///
/// This module provides utilities for writing tests (both doctests and integration tests)
/// that need to interact with the main thread. Since many platforms require UI operations
/// to run on the main thread, these utilities help set up and tear down the appropriate
/// environment for testing.
///
/// # Available utilities
///
/// - `doctest_main` - For writing doctests that need main thread access
/// - `integration_test_harness` - For integration tests with custom harness
///
/// # Example
///
/// For doctests that use async window operations:
/// ```
/// #[cfg(target_arch = "wasm32")] {
/// }
/// use app_window::test_support::doctest_main;
///
/// doctest_main(|| {
///     // Your test code here - has access to main thread
/// });
/// ```
///
/// See the module documentation for more details and integration test examples.
pub mod test_support;

/// Describes the preferred strategy for interacting with wgpu on different platforms.
///
/// Different platforms have different requirements for which thread can access
/// graphics APIs. This enum encodes those platform-specific requirements to help
/// applications use wgpu correctly.
///
/// # Example
///
/// ```
/// use app_window::{WGPU_STRATEGY, WGPUStrategy};
///
/// // Check the platform's wgpu threading requirements
/// match WGPU_STRATEGY {
///     WGPUStrategy::MainThread => {
///         println!("wgpu must be accessed from the main thread");
///     }
///     WGPUStrategy::NotMainThread => {
///         println!("wgpu must NOT be accessed from the main thread");
///     }
///     WGPUStrategy::Relaxed => {
///         println!("wgpu can be accessed from any thread");
///     }
///     _ => {
///         println!("Unknown strategy - using default behavior");
///     }
/// }
/// ```
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
#[non_exhaustive]
pub enum WGPUStrategy {
    /// The main thread should be used to access wgpu.
    ///
    /// This is required on WebAssembly and some macOS configurations where
    /// the graphics context must be created and used from the main thread.
    MainThread,

    /// The main thread should NOT be used to access wgpu.
    ///
    /// This is required on Linux with Wayland, where blocking the main thread
    /// with graphics operations can cause compositor issues.
    NotMainThread,

    /// On this platform, wgpu types are sendable and can be used from any thread.
    ///
    /// This is the case on Windows and most macOS configurations, providing
    /// maximum flexibility for application architecture.
    Relaxed,
}

/// Displays an alert dialog with the given message.
///
/// This function displays a modal alert dialog to the user. The behavior is platform-specific:
///
/// - **WebAssembly**: Uses the browser's native `window.alert()` function
/// - **macOS, Windows, Linux**: Not yet implemented (will panic with `todo!`)
///
/// # Platform-specific behavior
///
/// On WebAssembly, this function will block execution until the user dismisses the alert dialog.
/// The function automatically dispatches to the main thread as required by the platform.
///
/// # Example
///
/// ```no_run
/// # // no_run because: alert() requires application::main() to be called first, which is not available in doctests
/// # async fn example() {
/// use app_window::alert;
///
/// alert("Hello, world!".to_string()).await;
/// # }
/// ```
///
/// # Panics
///
/// Currently panics with `todo!` on macOS, Windows, and Linux platforms.
pub async fn alert(message: String) {
    sys::alert(message).await
}

/// The preferred strategy for interacting with wgpu on the current platform.
///
/// This constant provides the platform-specific threading requirements for wgpu
/// operations. Applications should check this value to determine the correct
/// thread to use for wgpu initialization and rendering.
///
/// # Platform Values
///
/// - **Linux**: `NotMainThread` - wgpu should be accessed from a worker thread
/// - **Windows**: `Relaxed` - wgpu can be accessed from any thread
/// - **macOS**: `Relaxed` - wgpu can be accessed from any thread
/// - **WebAssembly**: `MainThread` - wgpu must be accessed from the main thread
#[cfg(target_os = "linux")]
pub const WGPU_STRATEGY: WGPUStrategy = WGPUStrategy::NotMainThread;

/// The preferred strategy for interacting with wgpu on the current platform.
///
/// See [`WGPU_STRATEGY`] documentation for details.
#[cfg(target_os = "windows")]
pub const WGPU_STRATEGY: WGPUStrategy = WGPUStrategy::Relaxed;

/// The preferred strategy for interacting with wgpu on the current platform.
///
/// See [`WGPU_STRATEGY`] documentation for details.
#[cfg(target_os = "macos")]
pub const WGPU_STRATEGY: WGPUStrategy = WGPUStrategy::Relaxed;

/// The preferred strategy for interacting with wgpu on the current platform.
///
/// See [`WGPU_STRATEGY`] documentation for details.
#[cfg(target_arch = "wasm32")]
pub const WGPU_STRATEGY: WGPUStrategy = WGPUStrategy::MainThread;

/// The preferred strategy for interacting with wgpu surfaces on the current platform.
///
/// This constant provides the platform-specific threading requirements for wgpu
/// surface creation and configuration. Some platforms have different requirements
/// for surface operations compared to general wgpu operations.
///
/// # Platform Values
///
/// - **Linux**: `NotMainThread` - surfaces should be created from a worker thread
/// - **Windows**: `Relaxed` - surfaces can be created from any thread
/// - **macOS**: `MainThread` - surfaces must be created from the main thread
/// - **WebAssembly**: `MainThread` - surfaces must be created from the main thread
///
/// # Difference from `WGPU_STRATEGY`
///
/// While `WGPU_STRATEGY` applies to general wgpu operations, `WGPU_SURFACE_STRATEGY`
/// specifically applies to surface creation and configuration. On macOS, for example,
/// general wgpu operations are `Relaxed` but surface operations require `MainThread`.
#[cfg(target_os = "linux")]
pub const WGPU_SURFACE_STRATEGY: WGPUStrategy = WGPUStrategy::NotMainThread;

/// The preferred strategy for interacting with wgpu surfaces on the current platform.
///
/// See [`WGPU_SURFACE_STRATEGY`] documentation for details.
#[cfg(target_os = "windows")]
pub const WGPU_SURFACE_STRATEGY: WGPUStrategy = WGPUStrategy::Relaxed;

/// The preferred strategy for interacting with wgpu surfaces on the current platform.
///
/// See [`WGPU_SURFACE_STRATEGY`] documentation for details.
#[cfg(target_os = "macos")]
pub const WGPU_SURFACE_STRATEGY: WGPUStrategy = WGPUStrategy::MainThread;

/// The preferred strategy for interacting with wgpu surfaces on the current platform.
///
/// See [`WGPU_SURFACE_STRATEGY`] documentation for details.
#[cfg(target_arch = "wasm32")]
pub const WGPU_SURFACE_STRATEGY: WGPUStrategy = WGPUStrategy::MainThread;