/*
    Hurry Curry! - a game about cooking
    Copyright 2024 metamuffin

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License only.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.

*/
use clap::Parser;
use std::{
    fs::File,
    io::{BufRead, BufReader, BufWriter, Write},
    path::PathBuf,
};

#[derive(Parser)]
struct Args {
    atlas_out: PathBuf,
    atlas_meta_out: PathBuf,
    inputs: Vec<PathBuf>,
}

fn main() {
    let Args {
        inputs,
        atlas_meta_out,
        atlas_out,
    } = Args::parse();

    let atlas_size = 1024;

    let mut cursor_x = 0;
    let mut cursor_y = 0;
    let mut row_height = 0;

    let mut texels = vec![vec![' '; atlas_size]; atlas_size];
    let mut metadata = Vec::new();

    println!("  savepack {atlas_out:?}");
    for path in inputs {
        let file = BufReader::new(File::open(&path).unwrap());
        let tex = file.lines().map(Result::unwrap).collect::<Vec<String>>();
        let name = path.file_stem().unwrap().to_str().unwrap().to_string();
        let (width, height) = (tex[0].chars().count(), tex.len());

        println!("    + {width}x{height} {name}");

        if cursor_x + width > atlas_size {
            cursor_y += row_height;
            row_height = 0;
            cursor_x = 0;
        }
        if cursor_y + height > atlas_size {
            panic!("texture too big or atlas full");
        }
        row_height = row_height.max(height);
        let texcoord = [cursor_x, cursor_y, width, height];

        for (y, line) in tex.iter().enumerate() {
            if line.is_empty() {
                continue;
            }
            for (x, char) in line.chars().enumerate() {
                texels[cursor_y + y][cursor_x + x] = char;
            }
        }

        metadata.push((texcoord, name));

        cursor_x += width;
    }

    let mut atlas_out = BufWriter::new(File::create(atlas_out).unwrap());
    let mut atlas_meta_out = BufWriter::new(File::create(atlas_meta_out).unwrap());

    for line in texels {
        for char in line {
            write!(atlas_out, "{char}").unwrap()
        }
        writeln!(atlas_out).unwrap();
    }

    for ([x, y, w, h], name) in metadata {
        writeln!(atlas_meta_out, "{x},{y},{w},{h},{name}").unwrap();
    }
}