use axum::{
    http::{header, StatusCode},
    response::{IntoResponse, Response},
};
use mime_guess::Mime;
use rust_embed::EmbeddedFile;

use crate::{error::Internal, ui::error::NotFound};

#[derive(rust_embed::Embed)]
#[folder = "target/ui"]
pub struct Assets;

impl Assets {
    pub fn load(path: impl AsRef<str>) -> Result<Asset, NotFound<String>> {
        let path = path.as_ref();
        let mime = mime_guess::from_path(path).first_or_octet_stream();

        Self::get(path)
            .map(|file| Asset(mime, file))
            .ok_or(NotFound(format!("not found: {path}")))
    }

    pub fn index() -> Result<Asset, Internal> {
        // "not found" in this case really is an internal error, as it should
        // never happen. `index.html` is a known-valid path.
        Ok(Self::load("index.html")?)
    }
}

pub struct Asset(Mime, EmbeddedFile);

impl IntoResponse for Asset {
    fn into_response(self) -> Response {
        let Self(mime, file) = self;
        (
            StatusCode::OK,
            [(header::CONTENT_TYPE, mime.as_ref())],
            file.data,
        )
            .into_response()
    }
}