//! Router assembly and middleware wiring.
//!
//! [`build_app`] is the single entry point used by both `main.rs` and the
//! integration tests. It mounts the health probe and the public `/api`
//! display endpoints, then defers every unmatched path to the static SPA
//! service, and wraps the whole stack in the HTTP tracing layer.
//!
//! Extension points for todos 15-18: extend `api::router()` with the OAuth
//! and session routes (they receive [`AppState`] via `State<AppState>` once
//! `with_state` runs). Stateful routes MUST be added before the
//! `fallback_service` call.

use axum::Router;
use axum::routing::get;
use tower_http::trace::TraceLayer;

use crate::state::AppState;
use crate::{api, health, static_files};

/// Build the application router.
///
/// Returns a state-resolved `Router` ready for `axum::serve` or
/// `tower::ServiceExt::oneshot`.
pub fn build_app(state: AppState) -> Router {
  let router: Router<AppState> = Router::new()
    .route("/healthz", get(health::healthz))
    .route("/oauth/start", get(crate::oauth::start))
    .route("/callback", get(crate::oauth::callback))
    .nest("/api", api::router(state.sessions().clone()))
    .fallback_service(static_files::service(state.config().dist_dir()));

  router.layer(TraceLayer::new_for_http()).with_state(state)
}