use clap::Parser;
use std::{
    collections::HashMap,
    fs::File,
    io::{BufWriter, Write},
    path::PathBuf,
    process::exit,
};

#[derive(Parser)]
struct Args {
    input: PathBuf,
    output: PathBuf,
}

fn main() {
    let Args { input, output } = Args::parse();

    let palette = include_str!("../../../textures/palette.csv")
        .split('\n')
        .filter(|l| !l.is_empty())
        .map(|s| {
            let (c, s) = s.split_once(",").unwrap();
            let (r, s) = s.split_once(",").unwrap();
            let (g, s) = s.split_once(",").unwrap();
            let (b, a) = s.split_once(",").unwrap();
            (
                [
                    r.parse().unwrap(),
                    g.parse().unwrap(),
                    b.parse().unwrap(),
                    a.parse().unwrap(),
                ],
                c.chars().next().unwrap(),
            )
        })
        .collect::<HashMap<_, _>>();

    let input = image::open(input).unwrap().to_rgba8();
    let mut output = BufWriter::new(File::create(output).unwrap());

    for y in 0..input.height() {
        for x in 0..input.width() {
            let mut c = input.get_pixel(x, y).0;
            if c[3] == 0 {
                c = [0, 0, 0, 0];
            }
            let Some(char) = palette.get(&c) else {
                eprintln!("color at {x},{y} not in palette: {c:?}");
                exit(1);
            };
            write!(output, "{char}").unwrap();
        }
        writeln!(output).unwrap();
    }
    output.flush().unwrap();
    output.into_inner().unwrap().flush().unwrap()
}