/*
Additionnal build, doc: https://doc.rust-lang.org/cargo/reference/build-scripts.html

What is build here:
 - Compile the SASS file to CSS file.
*/

use std::{
    env,
    path::Path,
    process::{Command, Output},
};

fn exists_in_path<P>(filename: P) -> bool
where
    P: AsRef<Path>,
{
    for path in env::split_paths(&env::var_os("PATH").unwrap()) {
        if path.join(&filename).is_file() {
            return true;
        }
    }
    false
}

fn main() {
    println!("cargo:rerun-if-changed=style.scss");

    fn run_sass(command: &mut Command) -> Output {
        command
            .arg("--no-source-map")
            .arg("scss/style.scss")
            .arg("static/style.css")
            .output()
            .expect("Unable to compile SASS file, install SASS, see https://sass-lang.com/")
    }

    let output = if exists_in_path("sass.bat") {
        run_sass(Command::new("cmd").args(["/C", "sass.bat"]))
    } else {
        run_sass(&mut Command::new("sass"))
    };

    if !output.status.success() {
        // SASS will put the error in the file.
        let error =
            std::fs::read_to_string("./static/style.css").expect("unable to read style.css");
        panic!("{}", error);
    }
}