use distance_field::DistanceFieldExt;
use docopt::Docopt;
use image::{DynamicImage, GenericImageView};

const USAGE: &'static str = "
Usage:
    generator <source> <dest> <width> <height>
    generator (-h | --help)

Options:
    -h --help      Show this screen.
";

fn main() {
    let args = Docopt::new(USAGE)
        .and_then(|d| d.parse())
        .unwrap_or_else(|e| e.exit());

    let img = image::open(args.get_str("<source>")).unwrap();

    println!("Loaded image with size {:?}", img.dimensions());

    let width = args.get_str("<width>").parse::<usize>().unwrap();
    let height = args.get_str("<height>").parse::<usize>().unwrap();
    println!(
        "Converting image to distance field image with size ({:?}, {:?})...",
        width, height
    );

    let outbuf = img.grayscale().distance_field(distance_field::Options {
        max_distance: 256,
        size: (width, height),
        ..Default::default()
    });

    println!(
        "Saving distance field image to {:?}",
        args.get_str("<dest>")
    );
    DynamicImage::ImageLuma8(outbuf)
        .save(args.get_str("<dest>"))
        .unwrap();
}