use std::net::SocketAddr;

use anyhow::{Context, Result};
use axum::{
    http::StatusCode,
    response::{IntoResponse, Response},
    routing::get,
    Router,
};
use tower_http::{
    catch_panic::CatchPanicLayer,
    trace::{self, TraceLayer},
};
use tracing::{error, info, Level};
use tracing_subscriber::FmtSubscriber;

fn handle_panic(err: Box<dyn std::any::Any + Send + 'static>) -> Response {
    let details = if let Some(s) = err.downcast_ref::<String>() {
        s.clone()
    } else if let Some(s) = err.downcast_ref::<&str>() {
        s.to_string()
    } else {
        "Unknown panic message".to_string()
    };
    error!(details = details, "Handler paniced");

    (StatusCode::INTERNAL_SERVER_ERROR).into_response()
}

#[tokio::main]
async fn main() -> Result<()> {
    let subscriber = FmtSubscriber::builder()
        .with_max_level(Level::TRACE)
        .finish();
    tracing::subscriber::set_global_default(subscriber)
        .expect("set global default subscriber failed");

    let app = Router::new()
        .route("/", get(|| async { "wat" }))
        .layer(CatchPanicLayer::custom(handle_panic))
        .layer(
            TraceLayer::new_for_http()
                .make_span_with(trace::DefaultMakeSpan::new().level(Level::INFO))
                .on_response(trace::DefaultOnResponse::new().level(Level::INFO)),
        );

    let addr = "0.0.0.0:4800";
    info!("Listening on {addr}");
    let listener = tokio::net::TcpListener::bind(addr).await.unwrap();
    axum::serve(
        listener,
        app.into_make_service_with_connect_info::<SocketAddr>(),
    )
    .await
    .context("serve")
}