use chrono::{Datelike, Duration, Local, NaiveDate};
use rocket::{
    catch, catchers,
    fairing::AdHoc,
    fs::FileServer,
    get,
    request::FlashMessage,
    response::{Flash, Redirect},
    routes, Build, Rocket, State,
};
use rocket_dyn_templates::{tera::Context, Template};
use serde::Deserialize;
use sqlx::SqlitePool;

use crate::model::{
    log::Log,
    planned_event::PlannedEvent,
    tripdetails::TripDetails,
    triptype::TripType,
    user::User,
    usertrip::{UserTrip, UserTripError},
    Day,
};

mod admin;
mod auth;
mod cox;
mod misc;

fn amount_days_to_show(is_cox: bool) -> i64 {
    if is_cox {
        let end_of_year = NaiveDate::from_ymd_opt(Local::now().year(), 12, 31).unwrap(); //Ok,
                                                                                         //december
                                                                                         //has 31
                                                                                         //days
        end_of_year
            .signed_duration_since(Local::now().date_naive())
            .num_days()
            + 1
    } else {
        6
    }
}

#[get("/")]
async fn index(db: &State<SqlitePool>, user: User, flash: Option<FlashMessage<'_>>) -> Template {
    let mut days = Vec::new();

    let mut context = Context::new();

    if user.is_cox || user.is_admin {
        let triptypes = TripType::all(db).await;
        context.insert("trip_types", &triptypes);
    }

    let show_next_n_days = amount_days_to_show(user.is_cox);
    for i in 0..show_next_n_days {
        let date = (Local::now() + Duration::days(i)).date_naive();

        if user.is_guest {
            days.push(Day::new_guest(db, date, false).await);
        } else {
            days.push(Day::new(db, date, false).await);
        }
    }

    for date in PlannedEvent::pinned_days(db, show_next_n_days).await {
        //TODO: extract the 2 if's (this block + prev. one) after the 2 for's
        if user.is_guest {
            days.push(Day::new_guest(db, date, true).await);
        } else {
            days.push(Day::new(db, date, true).await);
        }
    }

    if let Some(msg) = flash {
        context.insert("flash", &msg.into_inner());
    }
    context.insert("loggedin_user", &user);
    context.insert("days", &days);
    Template::render("index", context.into_json())
}

#[get("/join/<trip_details_id>")]
async fn join(db: &State<SqlitePool>, trip_details_id: i64, user: User) -> Flash<Redirect> {
    let Some(trip_details) = TripDetails::find_by_id(db, trip_details_id).await else { return Flash::error(Redirect::to("/"), "Trip_details do not exist.") };

    match UserTrip::create(db, &user, &trip_details).await {
        Ok(_) => {
            Log::create(
                db,
                format!(
                    "User {} registered for trip_details.id={}",
                    user.name, trip_details_id
                ),
            )
            .await;
            Flash::success(Redirect::to("/"), "Erfolgreich angemeldet!")
        }
        Err(UserTripError::EventAlreadyFull) => {
            Flash::error(Redirect::to("/"), "Event bereits ausgebucht!")
        }
        Err(UserTripError::AlreadyRegistered) => {
            Flash::error(Redirect::to("/"), "Du nimmst bereits teil!")
        }
        Err(UserTripError::AlreadyRegisteredAsCox) => {
            Flash::error(Redirect::to("/"), "Du hilfst bereits als Steuerperson aus!")
        }
        Err(UserTripError::CantRegisterAtOwnEvent) => Flash::error(
            Redirect::to("/"),
            "Du kannst bei einer selbst ausgeschriebenen Fahrt nicht mitrudern ;)",
        ),
        Err(UserTripError::GuestNotAllowedForThisEvent) => Flash::error(
            Redirect::to("/"),
            "Bei dieser Ausfahrt können leider keine Gäste mitfahren.",
        ),
    }
}

#[get("/remove/<trip_details_id>")]
async fn remove(db: &State<SqlitePool>, trip_details_id: i64, user: User) -> Flash<Redirect> {
    let Some(trip_details) = TripDetails::find_by_id(db, trip_details_id).await else {
             return Flash::error(Redirect::to("/"), "TripDetailsId does not exist");
         };

    UserTrip::delete(db, &user, &trip_details).await;

    Log::create(
        db,
        format!(
            "User {} unregistered for trip_details.id={}",
            user.name, trip_details_id
        ),
    )
    .await;

    Flash::success(Redirect::to("/"), "Erfolgreich abgemeldet!")
}

#[catch(401)] //unauthorized
fn unauthorized_error() -> Redirect {
    Redirect::to("/auth")
}

#[derive(Deserialize)]
#[serde(crate = "rocket::serde")]
pub struct Config {
    rss_key: String,
}

pub fn start(db: SqlitePool) -> Rocket<Build> {
    rocket::build()
        .manage(db)
        .mount("/", routes![index, join, remove])
        .mount("/auth", auth::routes())
        .mount("/cox", cox::routes())
        .mount("/admin", admin::routes())
        .mount("/", misc::routes())
        .mount("/public", FileServer::from("static/"))
        .register("/", catchers![unauthorized_error])
        .attach(Template::fairing())
        .attach(AdHoc::config::<Config>())
}

//#[cfg(test)]
//mod test {
//    use crate::testdb;
//
//    use super::start;
//    use rocket::http::Status;
//    use rocket::local::asynchronous::Client;
//    use rocket::uri;
//    use sqlx::SqlitePool;
//
//    #[sqlx::test]
//    fn test_not_logged_in() {
//        let pool = testdb!();
//
//        let client = Client::tracked(start(pool))
//            .await
//            .expect("valid rocket instance");
//        let response = client.get(uri!(super::index)).dispatch().await;
//
//        assert_eq!(response.status(), Status::SeeOther);
//        let location = response.headers().get("Location").next().unwrap();
//        assert_eq!(location, "/auth");
//    }
//}