use axum::http::StatusCode;
use axum::response::Redirect;
use axum::Form;
use axum_login::AuthSession;

use super::internal_error;
use crate::prelude::*;
use crate::session::Credentials;

pub struct LoginTemplate {
    pub username: String,
    pub password: String,
    pub error: Option<String>,
}

pub async fn login_page(
    State(provider): State<Provider>,
    auth_session: AuthSession<Provider>,
) -> Result<Response, (StatusCode, String)> {
    if let Some(_user) = auth_session.user {
        Ok(Redirect::to("/").into_response())
    } else {
        render_login_page(&provider, "", "", None)
    }
}

fn render_login_page(
    provider: &Provider,
    username: &str,
    password: &str,
    error: Option<&'static str>,
) -> Result<Response, (StatusCode, String)> {
    provider.render_resp(
        "login.html",
        context! {
            username => username,
            password => password,
            error => error,
        },
    )
}

const LOGIN_ERROR_MSG: &str = "Invalid username or password";

pub async fn login_submit(
    State(provider): State<Provider>,
    mut auth_session: AuthSession<Provider>,
    Form(creds): Form<Credentials>,
) -> Result<Response, (StatusCode, String)> {
    if let Some(user) = auth_session.authenticate(creds).await.map_err(internal_error)? {
        auth_session.login(&user).await.map_err(internal_error)?;
        Ok(Redirect::to("/").into_response())
    } else {
        render_login_page(&provider, "", "", Some(LOGIN_ERROR_MSG))
    }
}

pub async fn logout(mut auth_session: AuthSession<Provider>) -> Response {
    if let Err(err) = auth_session.logout().await {
        error!(?err, "error while logging out user");
    }

    Redirect::to("/login").into_response()
}