use chrono::{DateTime, NaiveDateTime, Utc};
use serde::Deserialize;
use serde_json::Value;

use crate::{travelynx::TrainRef, types::IsStation, serde::*};

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
pub struct TripInfo {
    trip: Trip,
    connection: Option<Value>,
    selected_route: Option<Value>,
    active: Option<Value>
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
struct Trip {
    train_type: String,
    vzn: String, // train number
    // some position info here
    actual_position: u64, // distance along track, presumably
    stops: Vec<Stop>
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
pub struct Stop {
    info: StopInfo,
    station: Station,
    timetable: Timetable
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
struct StopInfo {
    distance_from_start: u64,
    position_status: String // one of "departed", "future", ... ?
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
struct Station {
    eva_nr: String,
    name: String
}

#[derive(Deserialize, Debug)]
#[serde(rename_all = "camelCase")]
struct Timetable {
    #[serde(deserialize_with = "option_naive_read_unixtime_db")]
    scheduled_arrival_time: Option<DateTime<Utc>>,
    #[serde(deserialize_with = "option_naive_read_unixtime_db")]
    actual_arrival_time: Option<DateTime<Utc>>
}

impl IsStation for Stop {
    fn name (&self) -> &str {
        &self.station.name
    }

    fn scheduled_arrival (&self) -> Option<&chrono::DateTime<Utc>> {
        self.timetable.scheduled_arrival_time.as_ref()
    }

    fn real_arrival (&self) -> Option<&chrono::DateTime<Utc>> {
        self.timetable.scheduled_arrival_time.as_ref()
    }

    fn ds100 (&self) -> &str {
        "??"
    }
}


impl TripInfo {

    pub fn guess_last_station (&self) -> Option<String> {
        let current_pos = self.trip.actual_position;
        self.trip
            .stops
            .iter()
            .rev()
            .map(|stop| (stop.info.distance_from_start, stop))
            .filter(|(dist,_)| dist <= &current_pos)
            .next()
            .map(|(_,stop)| stop.station.name.clone())
    }

    pub fn get_train_ref (&self) -> TrainRef {
        TrainRef {
            _type: self.trip.train_type.clone(),
            no: self.trip.vzn.clone()
        }
    }

    pub fn trip (&self) -> crate::types::Trip<'_,Stop> {
        crate::types::Trip(&self.trip.stops)
    }
}