mod common;

use ccvl::kernel::Kernel;
use ccvl::*;

fn draw(
    img: &mut image::Image<image::SRGBA>,
    path: &Vec<(usize, usize)>,
    colour: image::SRGBA,
) {
    let n = path.len();
    for i in 0..n {
        let (x0, y0) = path[i];
        let (x1, y1) = path[(i + 1) % n];
        draw::line(x0, y0, x1, y1, img, colour);
    }
}

fn approx(a: f32, b: f32, epsilon: f32) -> bool {
    (a - b).abs() <= epsilon
}

fn main() -> std::process::ExitCode {
    common::process_image(|mut img| {
        let greyscale = img.map(|p| image::Luminance::from(p));
        let blurred = kernel::gaussian::<5>(1.2).convolve_sat(&greyscale);
        let thresholded = filter::threshold_auto(blurred);
        let contours =
            contour::find(&thresholded, image::Luminance { y: 0.0 });
        for contour in contours {
            draw(&mut img, &contour.vertices, match contour.kind {
				contour::Kind::Outer => colours::GREEN,
				contour::Kind::Inner => colours::BLUE,
			});
        }
        img
    })
}