use std::env;
use std::path::{PathBuf};

use pelite::{FileMap, PeFile};

const HELP_TEXT: &str = "\
EXTRACT-ICONS <BINARY> <DEST>

  BINARY -- Path to the binary to extract icons from.
  DEST   -- Destination folder to write the icons to.
";

fn main() {
	let mut args = env::args_os();
	let _ = args.next();

	match (args.next(), args.next(), args.next()) {
		(Some(bin), Some(dest), None) => {
			let map = FileMap::open(&bin).expect("Error opening the binary");
			let file = PeFile::from_bytes(&map).expect("Error parsing the binary");
			let dest = PathBuf::from(dest);
			let resources = file.resources().expect("Error binary does not have resources");
			for (name, group) in resources.icons().filter_map(Result::ok) {
				// Write the ICO file
				let mut contents = Vec::new();
				group.write(&mut contents).unwrap();
				let path = dest.join(&format!("{}.ico", name));
				println!("{}", path.display());
				let _ = std::fs::write(&path, &contents);
			}
		},
		(None, _, _) => {
			eprintln!("{}", HELP_TEXT);
		},
		_ => {
			eprintln!("Expecting arguments `binary.dll` `destination`");
		},
	}
}