use std::collections::{BTreeMap, HashMap, HashSet};

use serde::{Deserialize, Serialize};

use abstio::{CityName, FileWithProgress};
use abstutil::{prettyprint_usize, Counter, Timer};
use geom::{Distance, Duration, LonLat, Time};
use kml::{ExtraShape, ExtraShapes};
use map_model::{osm, Map};
use synthpop::{OrigPersonID, TripMode, TripPurpose};

#[derive(Serialize, Deserialize)]
pub struct PopDat {
    pub trips: Vec<OrigTrip>,
}

// Extract trip demand data from PSRC's Soundcast outputs.
pub fn import_data(huge_map: &Map, timer: &mut Timer) -> PopDat {
    let trips = import_trips(huge_map, timer);
    let popdat = PopDat { trips };
    abstio::write_binary(abstio::path_popdat(), &popdat);
    popdat
}

fn import_trips(huge_map: &Map, timer: &mut Timer) -> Vec<OrigTrip> {
    let (parcels, mut keyed_shapes) = import_parcels(huge_map, timer);

    let mut trips = Vec::new();
    let (reader, done) =
        FileWithProgress::new(&CityName::seattle().input_path("trips_2014.csv")).unwrap();
    let mut total_records = 0;
    let mut people: HashSet<OrigPersonID> = HashSet::new();
    let mut trips_from_parcel: Counter<usize> = Counter::new();
    let mut trips_to_parcel: Counter<usize> = Counter::new();

    for rec in csv::Reader::from_reader(reader).deserialize() {
        total_records += 1;
        let rec: RawTrip = rec.unwrap();

        let from = parcels[&(rec.opcl as usize)].clone();
        let to = parcels[&(rec.dpcl as usize)].clone();
        trips_from_parcel.inc(from.parcel_id);
        trips_to_parcel.inc(to.parcel_id);

        // If both are None, then skip -- the trip doesn't start or end within huge_seattle.
        // If both are the same building, also skip -- that's a redundant trip.
        if from.osm_building == to.osm_building {
            if from.osm_building.is_some() {
                /*warn!(
                    "Skipping trip from parcel {} to {}; both match OSM building {:?}",
                    rec.opcl, rec.dpcl, from.osm_building
                );*/
            }
            continue;
        }

        let depart_at = Time::START_OF_DAY + Duration::minutes(rec.deptm as usize);

        let mode = get_mode(&rec.mode);
        let purpose = get_purpose(&rec.dpurp);

        let trip_time = Duration::f64_minutes(rec.travtime);
        let trip_dist = Distance::miles(rec.travdist);

        let person = OrigPersonID(rec.hhno as usize, rec.pno as usize);
        people.insert(person);
        #[allow(clippy::float_cmp)]
        let seq = (rec.tour as usize, rec.half == 2.0, rec.tseg as usize);

        trips.push(OrigTrip {
            from,
            to,
            depart_at,
            mode,
            person,
            seq,
            purpose,
            trip_time,
            trip_dist,
        });
    }
    done(timer);

    info!(
        "{} trips total, over {} people. {} records filtered out",
        prettyprint_usize(trips.len()),
        prettyprint_usize(people.len()),
        prettyprint_usize(total_records - trips.len())
    );

    trips.sort_by_key(|t| t.depart_at);

    // Dump debug info about parcels. ALL trips are counted here, but parcels are filtered.
    for (id, cnt) in trips_from_parcel.consume() {
        if let Some(ref mut es) = keyed_shapes.get_mut(&id) {
            es.attributes
                .insert("trips_from".to_string(), cnt.to_string());
        }
    }
    for (id, cnt) in trips_to_parcel.consume() {
        if let Some(ref mut es) = keyed_shapes.get_mut(&id) {
            es.attributes
                .insert("trips_to".to_string(), cnt.to_string());
        }
    }
    let shapes: Vec<ExtraShape> = keyed_shapes.into_iter().map(|(_, v)| v).collect();
    abstio::write_binary(
        CityName::seattle().input_path("parcels.bin"),
        &ExtraShapes { shapes },
    );

    trips
}

// TODO Do we also need the zone ID, or is parcel ID globally unique?
// Keyed by parcel ID
#[cfg(feature = "scenarios")]
fn import_parcels(
    huge_map: &Map,
    timer: &mut Timer,
) -> (HashMap<usize, Endpoint>, BTreeMap<usize, ExtraShape>) {
    use geom::FindClosest;

    // TODO I really just want to do polygon containment with a quadtree. FindClosest only does
    // line-string stuff right now, which'll be weird for the last->first pt line and stuff.
    let mut closest_bldg: FindClosest<osm::OsmID> = FindClosest::new(huge_map.get_bounds());
    for b in huge_map.all_buildings() {
        closest_bldg.add(b.orig_id, b.polygon.points());
    }

    let mut x_coords: Vec<f64> = Vec::new();
    let mut y_coords: Vec<f64> = Vec::new();
    // Dummy values
    let mut z_coords: Vec<f64> = Vec::new();
    // (parcel ID, number of households, number of parking spots)
    let mut parcel_metadata = Vec::new();

    let (reader, done) =
        FileWithProgress::new(&CityName::seattle().input_path("parcels_urbansim.txt")).unwrap();
    for rec in csv::ReaderBuilder::new()
        .delimiter(b' ')
        .from_reader(reader)
        .deserialize()
    {
        let rec: RawParcel = rec.unwrap();
        // Note parkdy_p and parkhr_p might overlap, so this could be double-counting. >_<
        parcel_metadata.push((rec.parcelid, rec.hh_p, rec.parkdy_p + rec.parkhr_p));
        x_coords.push(rec.xcoord_p);
        y_coords.push(rec.ycoord_p);
        z_coords.push(0.0);
    }
    done(timer);

    timer.start(format!("transform {} points", parcel_metadata.len()));

    // From https://epsg.io/102748 to https://epsg.io/4326
    let transform = gdal::spatial_ref::CoordTransform::new(
        &gdal::spatial_ref::SpatialRef::from_proj4(
            "+proj=lcc +lat_1=47.5 +lat_2=48.73333333333333 +lat_0=47 +lon_0=-120.8333333333333 \
             +x_0=500000.0000000002 +y_0=0 +datum=NAD83 +units=us-ft +no_defs",
        )
        .expect("washington state plane"),
        &gdal::spatial_ref::SpatialRef::from_epsg(4326).unwrap(),
    )
    .expect("regular GPS");
    transform
        .transform_coords(&mut x_coords, &mut y_coords, &mut z_coords)
        .expect("transform coords");

    timer.stop(format!("transform {} points", parcel_metadata.len()));

    let bounds = huge_map.get_gps_bounds();
    let boundary = huge_map.get_boundary_polygon();
    let mut result = HashMap::new();
    let mut shapes = BTreeMap::new();
    timer.start_iter("finalize parcel output", parcel_metadata.len());
    for ((x, y), (id, num_households, offstreet_parking_spaces)) in x_coords
        .into_iter()
        .zip(y_coords.into_iter())
        .zip(parcel_metadata.into_iter())
    {
        timer.next();
        // This maybe got inverted with some new version of GDAL?!
        let gps = LonLat::new(y, x);
        let pt = gps.to_pt(bounds);
        let osm_building = if bounds.contains(gps) {
            closest_bldg
                .closest_pt(pt, Distance::meters(30.0))
                .map(|(b, _)| b)
        } else {
            None
        };
        result.insert(
            id,
            Endpoint {
                pos: gps,
                osm_building,
                parcel_id: id,
            },
        );

        if boundary.contains_pt(pt) {
            let mut attributes = BTreeMap::new();
            attributes.insert("id".to_string(), id.to_string());
            if num_households > 0 {
                attributes.insert("households".to_string(), num_households.to_string());
            }
            if offstreet_parking_spaces > 0 {
                attributes.insert("parking".to_string(), offstreet_parking_spaces.to_string());
            }
            if let Some(b) = osm_building {
                attributes.insert("osm_bldg".to_string(), b.inner().to_string());
            }
            shapes.insert(
                id,
                ExtraShape {
                    points: vec![gps],
                    attributes,
                },
            );
        }
    }
    info!("{} parcels", prettyprint_usize(result.len()));

    (result, shapes)
}

#[cfg(not(feature = "scenarios"))]
fn import_parcels(
    _: &Map,
    _: &mut Timer,
) -> (HashMap<usize, Endpoint>, BTreeMap<usize, ExtraShape>) {
    panic!("Can't import_parcels for popdat.bin without the scenarios feature (GDAL dependency)");
}

// From https://github.com/psrc/soundcast/wiki/Outputs#trip-file-_triptsv, dpurp
fn get_purpose(code: &str) -> TripPurpose {
    match code {
        "0.0" => TripPurpose::Home,
        "1.0" => TripPurpose::Work,
        "2.0" => TripPurpose::School,
        "3.0" => TripPurpose::Escort,
        "4.0" => TripPurpose::PersonalBusiness,
        "5.0" => TripPurpose::Shopping,
        "6.0" => TripPurpose::Meal,
        "7.0" => TripPurpose::Social,
        "8.0" => TripPurpose::Recreation,
        "9.0" => TripPurpose::Medical,
        "10.0" => TripPurpose::ParkAndRideTransfer,
        _ => panic!("Unknown dpurp {}", code),
    }
}

// From https://github.com/psrc/soundcast/wiki/Outputs#trip-file-_triptsv, mode
fn get_mode(code: &str) -> TripMode {
    match code {
        "1.0" => TripMode::Walk,
        "2.0" => TripMode::Bike,
        "3.0" | "4.0" | "5.0" => TripMode::Drive,
        // TODO Park-and-ride and school bus as walk-to-transit is a little weird.
        "6.0" | "7.0" | "8.0" => TripMode::Transit,
        // TODO Invalid code, what's this one mean? I only see a few examples, so just default to
        // walking.
        "0.0" => TripMode::Walk,
        _ => panic!("Unknown mode {}", code),
    }
}

// See https://github.com/psrc/soundcast/wiki/Outputs#trip-file-_triptsv
//
// A/B Street flattens a person's trips into a simple list, but the Soundcast model is more
// detailed:
//
// A person takes 1+ tours a day. Each tour starts and ends at the same place (usually home) and
// has some primary destination. A tour has two legs (to the destination, then returning from it),
// each split into individual trips.
//
// An example: someone takes the bus to work, but stops for a coffee and walks the final bit to
// work. Then later they bus home. This would be encoded like so:
//
// - Tour 1 (purpose work), leg = to destination, trip 1 (purpose eat, using transit)
// - Tour 1 (purpose work), leg = to destination, trip 2 (purpose work, walking)
// - Tour 1 (purpose work), leg = return from destination, trip 1 (purpose home, using transit)
#[derive(Debug, Deserialize)]
struct RawTrip {
    opcl: f64,
    dpcl: f64,
    deptm: f64,
    mode: String,
    dpurp: String,
    travtime: f64,
    travdist: f64,
    hhno: f64,
    pno: f64,
    tour: f64,
    half: f64,
    tseg: f64,
}

// See https://github.com/psrc/soundcast/wiki/Outputs#buffered-parcel-file-buffered_parcelsdat
#[derive(Debug, Deserialize)]
// When the 'scenarios' feature is disabled, these fields look unused
#[allow(unused)]
struct RawParcel {
    parcelid: usize,
    hh_p: usize,
    parkdy_p: usize,
    parkhr_p: usize,
    xcoord_p: f64,
    ycoord_p: f64,
}

#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct OrigTrip {
    pub from: Endpoint,
    pub to: Endpoint,
    pub depart_at: Time,
    pub mode: TripMode,

    // (household, person within household)
    pub person: OrigPersonID,
    // (tour, false is to destination and true is back from dst, trip within half-tour)
    pub seq: (usize, bool, usize),
    // Purpose at the destination of this trip, not the entire tour.
    pub purpose: TripPurpose,
    pub trip_time: Duration,
    pub trip_dist: Distance,
}

#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct Endpoint {
    pub pos: LonLat,
    pub osm_building: Option<osm::OsmID>,
    pub parcel_id: usize,
}