use geo_svg_io::geo_svg_reader::svg_d_path_to_geometry;
use geo_types::{Coordinate, LineString, MultiPolygon, Polygon};
use std::error::Error;
use svg::node::element::tag::Path;
use svg::parser::Event;

#[allow(non_upper_case_globals)]
pub fn load_multipolgon_from_svg(path: &str) -> Result<MultiPolygon<f64>, Box<dyn Error>> {
    let mut content = String::new();
    let mut result: Vec<Polygon<f64>> = Vec::new();
    for event in svg::open(path, &mut content)? {
        match event {
            Event::Tag(Path, _, attributes) => {
                let data = attributes.get("d").unwrap();
                let parsed_svg = svg_d_path_to_geometry(&data).ok().unwrap();
                let polygon = parsed_svg.into_polygon().unwrap();

                // both libraries use different versions of geo-types, so we have to map them :facepalm:
                // map interiors
                let mut interiors: Vec<LineString<f64>> = Vec::new();
                for interior_line_string in polygon.interiors().to_vec() {
                    let mut new_line_string: Vec<Coordinate<f64>> = Vec::new();
                    for i in interior_line_string.into_points() {
                        new_line_string.push(Coordinate { x: i.x(), y: i.y() });
                    }
                    interiors.push(LineString::from(new_line_string));
                }
                // map exteriors
                let mut l: Vec<Coordinate<f64>> = Vec::new();
                for i in polygon.exterior().clone().into_points() {
                    l.push(Coordinate { x: i.x(), y: i.y() });
                }
                let exterior = LineString::from(l);

                result.push(Polygon::new(exterior, interiors));
            }
            _ => {}
        }
    }
    Ok(MultiPolygon::from(result))
}