//extern crate bindgen;

//use bindgen::CargoCallbacks;

fn main() {
    // Compile library 
    cc::Build::new()
        .file("libs/ncvm/src/ncvm.c")
        .include("libs/ncvm/include")
        .include("libs/extc/include")
        .opt_level(3)
        .debug(false)
        .warnings(false)
        .compile("c-ncvm-static");


    let bindings = bindgen::Builder::default()
        .header("libs/ncvm/include/ncvm.h")
        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
        .generate()
        .expect("Unable to generate bindings");

    let mut result = move_const_to_mod(
        &bindings.to_string(), "opcode", "OPCODE_"
    );
    result = move_const_to_mod(
        &result, "register", "REGISTER_"
    );
    result.insert_str(0, "#![allow(warnings)]\n");

    std::fs::write("src/ncvm.rs", result).unwrap();
}

fn move_const_to_mod(source: &String, mod_name: &str, const_keyword: &str) -> String {
    let mut result: String = String::with_capacity(source.len());
    let mut str_mod: String = String::from(format!("pub mod {mod_name} {{\n"));
    let mut post_mod = String::new();
    for line in source.split("\n") {
        let lw = line.split_whitespace().collect::<Vec<&str>>();
        
        if lw.len() == 6 && lw[0] == "pub" &&
           lw[1] == "const" && lw[2].starts_with(const_keyword) {
            str_mod.push_str(
                format!("\t{}\n", line.replace(const_keyword, "")).as_str()
            );
        }
        else if lw.len() >= 3 && lw[0] == "pub" &&
        lw[1] == "type" && format!("{}_", lw[2]) == const_keyword {
            str_mod.push_str(
                format!("\t{}\n", line.replace(const_keyword, "")).as_str()
            );
            post_mod = String::from(
                format!(
                    "use {}::{};\n", mod_name,
                    const_keyword.chars().take(const_keyword.len()-1).collect::<String>()
                )
            )
        }
        else {
            result.push_str(line);
            result.push('\n');
        }
    }
    str_mod.push_str("}\n");
    str_mod.push_str(&post_mod);
    result.insert_str(0, &str_mod);
    result
}