use rocket::{
    form::Form,
    get,
    http::{Cookie, CookieJar},
    post,
    request::FlashMessage,
    response::{Flash, Redirect},
    routes, FromForm, Route, State,
};
use rocket_dyn_templates::{context, tera, Template};
use serde_json::json;
use sqlx::SqlitePool;

use crate::model::user::{LoginError, User};

#[get("/")]
async fn index(flash: Option<FlashMessage<'_>>) -> Template {
    let mut context = tera::Context::new();

    if let Some(msg) = flash {
        context.insert("flash", &msg.into_inner());
    }

    Template::render("auth/login", context.into_json())
}

#[derive(FromForm)]
struct LoginForm {
    name: String,
    password: String,
}

#[post("/", data = "<login>")]
async fn login(
    login: Form<LoginForm>,
    db: &State<SqlitePool>,
    cookies: &CookieJar<'_>,
) -> Flash<Redirect> {
    let user = User::login(db, login.name.clone(), login.password.clone()).await;

    //TODO: be able to use ? for login. This would get rid of the following match clause.
    let user = match user {
        Ok(user) => user,
        Err(LoginError::NoPasswordSet(user)) => {
            return Flash::warning(
                Redirect::to(format!("/auth/set-pw/{}", user.id)),
                "Setze ein neues Passwort",
            );
        }
        Err(_) => {
            return Flash::error(Redirect::to("/auth"), "Falscher Benutzername/Passwort");
        }
    };

    let user_json: String = format!("{}", json!(user));
    cookies.add_private(Cookie::new("loggedin_user", user_json));

    Flash::success(Redirect::to("/"), "Login erfolgreich")
}

#[get("/set-pw/<userid>")]
async fn setpw(userid: i32) -> Template {
    Template::render("auth/set-pw", context!(userid))
}

#[derive(FromForm)]
struct UpdatePw {
    userid: i32,
    password: String,
    password_confirm: String,
}

#[post("/set-pw", data = "<updatepw>")]
async fn updatepw(
    db: &State<SqlitePool>,
    updatepw: Form<UpdatePw>,
    cookies: &CookieJar<'_>,
) -> Flash<Redirect> {
    let user = User::find_by_id(db, updatepw.userid).await;
    let user = match user {
        Ok(user) => user,
        Err(_) => {
            return Flash::error(
                Redirect::to("/auth"),
                format!("User with ID {} does not exist!", updatepw.userid),
            )
        }
    };

    if updatepw.password != updatepw.password_confirm {
        return Flash::error(
            Redirect::to(format!("/auth/set-pw/{}", updatepw.userid)),
            "Passwörter stimmen nicht überein! Bitte probiere es nochmal",
        );
    }

    user.update_pw(db, updatepw.password.clone()).await;

    let user_json: String = format!("{}", json!(user));
    cookies.add_private(Cookie::new("loggedin_user", user_json));

    Flash::success(
        Redirect::to("/"),
        "Passwort erfolgreich gesetzt. Du bist nun eingeloggt.",
    )
}

#[get("/logout")]
async fn logout(cookies: &CookieJar<'_>, _user: User) -> Flash<Redirect> {
    cookies.remove_private(Cookie::named("loggedin_user"));

    Flash::success(Redirect::to("/auth"), "Logout erfolgreich")
}

pub fn routes() -> Vec<Route> {
    routes![index, login, logout, setpw, updatepw]
}