//! The smallest slag consumer: one bundled component, one custom host
//! function, no icons, no async effects. Demonstrates the wiring an app owns —
//! build the host module, the runtime, a config, the components, the shell.

use std::rc::Rc;

use gpui::{px, size, AppContext, Bounds, WindowBounds, WindowOptions};
use slag_core::host::{self, with_ctx};
use slag_core::steel::rvals::SteelVal;
use slag_core::steel::steel_vm::builtin::BuiltInModule;
use slag_core::steel::steel_vm::register_fn::RegisterFn;
use slag_core::{Bundled, PackLoader, ScriptRuntime};
use slag_gpui::{SchemeComponent, Shell, UiConfig};

/// The app's host module: the framework builtins plus one app function.
fn host_module() -> BuiltInModule {
    let mut module = BuiltInModule::new("hello/host".to_string());
    host::register_builtins(&mut module);
    module.register_fn("motd", || -> SteelVal {
        // Host functions capture nothing (Steel demands Send + Sync); they
        // reach their component through the thread-local registry.
        let clicks = with_ctx(|c| c.state.borrow().len()).unwrap_or(0);
        SteelVal::StringV(format!("state slots in play: {clicks}").as_str().into())
    });
    module
}

fn main() {
    gpui_platform::application().run(|cx: &mut gpui::App| {
        gpui_component::init(cx);

        let bounds = Bounds::centered(None, size(px(480.0), px(320.0)), cx);
        cx.open_window(
            WindowOptions {
                window_bounds: Some(WindowBounds::Windowed(bounds)),
                ..Default::default()
            },
            |window, cx| {
                let runtime = Rc::new(ScriptRuntime::new(
                    PackLoader::bundled_only(Bundled {
                        components: &[("hello", include_str!("../packs/hello.scm"))],
                        libs: &[],
                    }),
                    host_module(),
                    &[],
                ));
                let config = Rc::new(UiConfig {
                    env_prefix: "HELLO",
                    icons: Rc::new(|_| None),
                    video_frames: None,
                });
                // No app context needed: `()` fills the type-erased slot.
                let hello = cx.new(|cx| {
                    SchemeComponent::new(Rc::new(()), runtime.clone(), config, "hello", cx)
                });
                let shell = cx.new(|cx| Shell::new(vec![("hello".into(), hello)], "hello", cx));
                cx.new(|cx| gpui_component::Root::new(shell, window, cx))
            },
        )
        .expect("failed to open window");
        cx.activate(true);
    });
}