use std::error::Error;
use std::io::Cursor;

use rocket::http::Method;
use rocket::Response;
use rocket::{get, options, routes};
use rocket_cors::{AllowedHeaders, AllowedOrigins, Guard, Responder};

/// Using a `Responder` -- the usual way you would use this
#[get("/")]
fn responder(cors: Guard<'_>) -> Responder<'_, '_, &str> {
    cors.responder("Hello CORS!")
}

/// Using a `Response` instead of a `Responder`. You generally won't have to do this.
#[get("/response")]
fn response(cors: Guard<'_>) -> Response<'_> {
    let mut response = Response::new();
    let body = "Hello CORS!";
    response.set_sized_body(body.len(), Cursor::new(body));
    cors.response(response)
}

/// Manually mount an OPTIONS route for your own handling
#[options("/manual")]
fn manual_options(cors: Guard<'_>) -> Responder<'_, '_, &str> {
    cors.responder("Manual OPTIONS preflight handling")
}

/// Manually mount an OPTIONS route for your own handling
#[get("/manual")]
fn manual(cors: Guard<'_>) -> Responder<'_, '_, &str> {
    cors.responder("Manual OPTIONS preflight handling")
}

#[rocket::main]
async fn main() -> Result<(), Box<dyn Error>> {
    let allowed_origins = AllowedOrigins::some_exact(&["https://www.acme.com"]);

    // You can also deserialize this
    let cors = rocket_cors::CorsOptions {
        allowed_origins,
        allowed_methods: vec![Method::Get].into_iter().map(From::from).collect(),
        allowed_headers: AllowedHeaders::some(&["Authorization", "Accept"]),
        allow_credentials: true,
        ..Default::default()
    }
    .to_cors()?;

    rocket::build()
        .mount("/", routes![responder, response])
        // Mount the routes to catch all the OPTIONS pre-flight requests
        .mount("/", rocket_cors::catch_all_options_routes())
        // You can also manually mount an OPTIONS route that will be used instead
        .mount("/", routes![manual, manual_options])
        .manage(cors)
        .launch()
        .await?;

    Ok(())
}