use axum::Router;
use axum::extract::State;
use axum::response::{Html, IntoResponse, Response};
use axum::routing::{get, post};
use axum::serve::Listener as AxumListener;
use axum_extra::extract::cookie::CookieJar;
use http::StatusCode;
#[cfg(not(feature = "embed"))]
use minijinja::path_loader;
use minijinja::{Environment, context};
#[cfg(feature = "embed")]
use static_serve::embed_assets;
#[cfg(not(feature = "embed"))]
use tower_http::services::ServeDir;

use crate::db::{Database, DatabaseInterface, Operation};
use crate::listener::{Listener, ListenerKind};
use crate::stream::{AbstractSocketAddr, AbstractStreamKind};

mod login;
mod logout;
mod session;
use session::HttpSessionManager;

impl AxumListener for Listener {
    type Io = AbstractStreamKind;
    type Addr = AbstractSocketAddr;

    async fn accept(&mut self) -> (Self::Io, Self::Addr) {
        loop {
            let res = match &self.kind {
                ListenerKind::Tcp(l) => l
                    .accept()
                    .await
                    .map(|(stream, remote_addr)| (stream.into(), remote_addr.into())),
                ListenerKind::Uds(l) => l
                    .accept()
                    .await
                    .map(|(stream, remote_addr)| (stream.into(), remote_addr.into())),
            };

            match res {
                Ok((stream, remote_addr)) => return (stream, remote_addr),
                Err(e) => {
                    // Here the error could be fatal, or could simply be that a client aborted the connected,
                    // in which case we don't want to crash the server, simply skip this client connection.
                    // https://doc.rust-lang.org/stable/std/net/struct.TcpListener.html#errors
                    match e.kind() {
                        std::io::ErrorKind::ConnectionAborted => {}
                        _ => panic!("Unrecoverable HTTP client connection error: {e}"),
                    }
                }
            }
        }
    }

    fn local_addr(&self) -> std::io::Result<Self::Addr> {
        match &self.kind {
            ListenerKind::Tcp(l) => l.local_addr().map(Into::into),
            ListenerKind::Uds(l) => l.local_addr().map(Into::into),
        }
    }
}

#[derive(Clone)]
pub struct HttpState<D: DatabaseInterface> {
    pub db: Database<D>,
    pub sessions: HttpSessionManager,
    pub templates: Environment<'static>,
}

impl<D: DatabaseInterface> HttpState<D> {
    pub fn new(db: Database<D>) -> Self {
        let mut templates = Environment::new();
        #[cfg(feature = "embed")]
        minijinja_embed::load_templates!(&mut templates);
        #[cfg(not(feature = "embed"))]
        templates.set_loader(path_loader("templates"));
        Self {
            db,
            sessions: HttpSessionManager::new(),
            templates,
        }
    }
}

pub async fn http_listen<D: DatabaseInterface>(listener: Listener, db: Database<D>) {
    #[cfg(all(feature = "embed", feature = "noembed"))]
    compile_error!("You cannot have `embed` and `noembed` features enabled at the same time.");
    #[cfg(not(any(feature = "embed", feature = "noembed")))]
    compile_error!("You must have `embed` or `noembed` feature enabled.");

    #[cfg(feature = "embed")]
    let app = {
        embed_assets!("assets");
        Router::new().nest("/assets", static_router())
    };
    #[cfg(not(feature = "embed"))]
    let app = { Router::new().nest_service("/assets", ServeDir::new("assets")) };
    let app = app
        .route("/", get(home))
        .route("/login", get(home))
        .route("/login", post(login::post_login))
        .route("/logout", get(logout::logout))
        .with_state(HttpState::new(db));

    axum::serve(listener, app).await.unwrap();
}

pub async fn home<D: DatabaseInterface>(
    State(state): State<HttpState<D>>,
    cookies: CookieJar,
) -> Response {
    if let Some(session) = state.sessions.get_session(&cookies) {
        // When the user has no domain (service admin) list all domains
        let op = Operation::ListUsers(session.user.domain.clone());
        let other_users = if session.user.can_perform(&op) {
            match state.db.list_users(session.user.domain.clone()).await {
                Ok(other_users) => other_users,
                Err(e) => {
                    return format!("Database error: {e}").into_response();
                }
            }
        } else {
            vec![]
        };

        tracing::info!(
            "Found {} users on domain {:?}",
            other_users.len(),
            session.user.domain
        );

        let ctx = context! {
            user => session.user,
            other_users,
        };

        let page = state
            .templates
            .get_template("home.html")
            .unwrap()
            .render(ctx)
            .unwrap();
        (StatusCode::OK, Html(page)).into_response()
    } else {
        login::login_page(State(state), None).await
    }
}