outlinify/src/geometry/union.rs

use std::collections::HashMap;

use clipper2::{FillRule, One, Paths, PointInPolygonResult};

use crate::geometry::helpers::do_intersect;

use super::{
    elements::{linepath::LinePath, Element},
    point::Point,
    ClipperPaths,
};

#[derive(Debug, Clone)]
pub struct ConductorNet {
    pub outline: ClipperPaths,
    pub included_points: Vec<Point>,
}

pub fn union_lines(lines: &[LinePath]) -> Vec<ConductorNet> {
    let mut intersection_map = HashMap::new();
    println!(
        "START LINE UNION of {:?}",
        lines
            .iter()
            .map(|l| l.points.clone())
            .collect::<Vec<Vec<Point>>>()
    );
    for (index, line) in lines.iter().enumerate() {
        if !line.is_empty() {
            // create list of intersecting lines
            let mut intersections = Vec::new();
            let (p1, q1) = (line.points[0], line.points[1]);
            println!("LINE 1 {p1:?}, {q1:?}");
            for (i, l) in lines.iter().enumerate() {
                if !l.is_empty() {
                    // do not check for intersection with itself
                    if index != i {
                        // check for all lines in path
                        let intersect = l.points.windows(2).any(|w| {
                            let (p2, q2) = (w[0], w[1]);
                            println!("LINE 2 {p2:?}, {q2:?}");
                            do_intersect(p1, q1, p2, q2)
                        });
                        println!("INTERSECTING: {intersect}");
                        if intersect {
                            // let entry = intersection_map.entry(index).or_insert(Vec::new());
                            // entry.push(i);
                            intersections.push(i);
                        }
                    }
                }
            }
            //
            intersection_map.insert(index, intersections);
        }
    }

    println!("{intersection_map:?}");
    let mut final_geo = Vec::new();

    // go through all line segments
    for i in 0..intersection_map.len() {
        if let Some(mut intersections) = intersection_map.remove(&i) {
            // if no intersections are given, add line as own conductor net
            // if intersections.is_empty() {
            //     if let Some(line) = lines.get(i) {
            //         final_geo.push(ConductorNet {
            //             outline: line.outline.clone(),
            //             included_points: line.points.clone(),
            //         })
            //     }
            // }

            println!("--- Taking line segment {i}");
            // get current line path
            let mut geo = lines[i].outline.clone();
            let mut included_points = lines[i].points.clone();

            // union with intersecting lines until done
            println!("Intersection points: {intersections:?}");
            while let Some(other) = intersections.pop() {
                println!("Intersecting with line # {other:?}");
                // union with intersecting line
                let intersecting_line = &lines[other];
                if let Some(union) = union(&geo, &intersecting_line.outline) {
                    geo = union;
                }
                // add points of added line to included points
                for point in &intersecting_line.points {
                    if !included_points.contains(point) {
                        included_points.push(point.to_owned()); // show included points
                    }
                }

                // get intersections of united line and add them if not already in own
                if let Some(new_intersections) = intersection_map.remove(&other) {
                    for o in new_intersections {
                        // add to original line if not self and not already inside
                        if o != i   // ensure to not intersect with itself
                            && !intersections.contains(&o)  // do not add if already in intersection list
                            && intersection_map.contains_key(&o)
                        // check if intersection was already performed
                        {
                            intersections.push(o);
                        }
                    }
                }
            }
            // create conductor net
            final_geo.push(ConductorNet {
                outline: geo,
                included_points,
            })
        }
    }

    // if final_geo.is_empty() {
    //     if let Some(line) = lines.get(0) {
    //         final_geo.push(ConductorNet {
    //             outline: line.outline.clone(),
    //             included_points: line.points.clone(),
    //         })
    //     }
    // }

    final_geo
}

pub fn union_with_apertures(
    apertures: &Vec<Element>,
    conductors: Vec<ConductorNet>,
) -> Option<ClipperPaths> {
    let mut finalized_paths = Vec::new(); // handle apertures without connection
    let mut current_conductors = conductors;

    // go through all apertures
    for ap in apertures {
        // get outline path
        let geo = ap.to_paths();
        // create empty set of conductors
        let mut new_conductors = Vec::new();
        // create indicator if aperture is isolated
        let mut isolated = true;

        // go through all available conductor nets
        for conductor in current_conductors {
            // check if any point of the conductor net is not outside of the aperture
            if conductor
                .included_points
                .iter()
                .any(|c| ap.outline().is_point_inside(c.into()) != PointInPolygonResult::IsOutside)
            {
                // union aperture with conductor net
                let geo = union(&geo, &conductor.outline)?;
                let mut cond = conductor;
                cond.outline = geo;
                isolated = false;
                new_conductors.push(cond);
            } else {
                new_conductors.push(conductor);
            }
        }

        // add aperture to extra container if isolated
        if isolated {
            finalized_paths.push(geo);
        }

        // update current conductors
        current_conductors = new_conductors;
    }

    for conductor in current_conductors {
        finalized_paths.push(conductor.outline);
    }

    finalized_paths.into_iter().reduce(|mut all, paths| {
        all.push(paths);
        all
    })
}

fn union(path1: &ClipperPaths, path2: &ClipperPaths) -> Option<ClipperPaths> {
    path1
        .to_clipper_subject()
        .add_clip(path2.clone())
        .union(FillRule::default())
        .ok()
}