use std::collections::HashMap;
use std::env;

fn main() {
    println!("cargo:rerun-if-env-changed=bench");
    if let Some(_val) = env::var_os("ntrust_bench") {
        println!("cargo:rustc-cfg=feature=\"bench\"");
    }
    let mut features = HashMap::new();
    features.insert("ntruhps2048509", cfg!(feature = "ntruhps2048509"));
    features.insert("ntruhps2048677", cfg!(feature = "ntruhps2048677"));
    features.insert("ntruhps4096821", cfg!(feature = "ntruhps4096821"));
    features.insert("ntruhrss701", cfg!(feature = "ntruhrss701"));

    let mut target_feature = "";
    for (feature, in_use) in features {
        if !target_feature.is_empty() && in_use {
            panic!("[ERROR] Configuration error: \n\t{} and {} cannot be used simultaneously!\n\tPlease select only one feature.", target_feature, feature);
        } else if in_use {
            target_feature = feature;
        }
    }

    if target_feature.is_empty() {
        println!("cargo:rustc-cfg=feature=\"ntruhps2048509\"");
        println!("cargo:rustc-cfg=feature=\"ntruhps\"");
    }
}