AOC 3.1

static void task5() {
//        String[] lines = openFile(new File("res/i4.txt"));
        List<String[]> lines = Arrays.stream(openFile(new File("res/i41.txt"))).map(x -> x.split(",")).collect(Collectors.toList());

        List<Vector2> line1 = new ArrayList<>(lines.get(0).length-1);
        Vector2 pos1 = new Vector2(0,0);
        for(int i = 0; i < lines.get(0).length; i++) {
            String s = lines.get(0)[i];
            String dir  = s.substring(0,1);
            int dist = Integer.parseInt(s.substring(1));
            switch (dir) {
                case "R":
                    pos1.add(dist, 0);
                    break;
                case "L":
                    pos1.add(-dist, 0);
                    break;
                case "U":
                    pos1.add(0, dist);
                    break;
                case "D":
                    pos1.add(0, -dist);
                    break;
            }
            line1.add(pos1.copy());
        }
        List<Vector2> intersections = new ArrayList<>();
        Vector2 line2a = new Vector2(0,0);
        for(int i = 0; i < lines.get(1).length; i++) {
            String s = lines.get(1)[i];
            String dir  = s.substring(0,1);
            int dist = Integer.parseInt(s.substring(1));
            Vector2 line2b = line2a.copy();
            switch (dir) {
                case "R":
                    line2b.add(dist, 0);
                    break;
                case "L":
                    line2b.add(-dist, 0);
                    break;
                case "U":
                    line2b.add(0, dist);
                    break;
                case "D":
                    line2b.add(0, -dist);
                    break;
            }
            for(int j = 0; j < line1.size() -1; j++) {
                Vector2 line1a = line1.get(j);
                Vector2 line1b = line1.get(j+1);
                boolean intersectionFound = false;
                if(dir.matches("[UD]") && line1a.getY() == line1b.getY()) { //horizontal
//                    System.out.println("LINE 1");
//                    line1a.show();
//                    line1b.show();
//                    System.out.println("LINE2");
//                    line2a.show();
//                    line2b.show();
                    int y1 = line1a.getY(), x2 = line2a.getX();
                    int x1min = Math.min(line1a.getX(), line1b.getX());
                    int x1max = Math.max(line1a.getX(), line1b.getX());
                    int y2min = Math.min(line2a.getY(), line2b.getY());
                    int y2max = Math.max(line2a.getY(), line2b.getY());
                    if(y1 > y2min && y1 < y2max && x1min < x2 && x1max > x2) {
                        intersectionFound = true;
                        Vector2 intersection = new Vector2(line2a.getX(), line1a.getY());
                        intersections.add(intersection);
                    }


                } else if(dir.matches("[LR]") && line1a.getX() == line1b.getX()){ //vertical
                    int x1 = line1a.getX(), y2 = line2a.getY();
                    int y1min = Math.min(line1a.getY(), line1b.getY());
                    int y1max = Math.max(line1a.getY(), line1b.getY());
                    int x2min = Math.min(line2a.getX(), line2b.getX());
                    int x2max = Math.max(line2a.getX(), line2b.getX());
                    if(x1 > x2min && x1 < x2max && y1min < y2 && y1max > y2) {
                        intersectionFound = true;
                        Vector2 intersection = new Vector2(line1a.getX(), line2a.getY());
                        intersections.add(intersection);
                    }
                }
            }
            line2a = line2b;
        }
        int min = Integer.MAX_VALUE;
        System.out.println("intersections found:");
        for(Vector2 v : intersections) {
            v.show();
            min = Math.min(min, v.manhattanLength());
        }
        System.out.println("shortest distance from intersection is:");
        System.out.println(min);
//        for(Vector2 v : line1)
//            System.out.println(v.getX() + ", " + v.getY());

    }