extern crate pkg_config;

use std::env;

fn main() {
    let lib_dir = env::var("CUDNN_LIB_DIR").ok();
    let include_dir = env::var("CUDNN_INCLUDE_DIR").ok();

    if lib_dir.is_none() && include_dir.is_none() {
        if let Ok(info) = pkg_config::find_library("cudnn") {
            // avoid empty include paths as they are not supported by GCC
            if info.include_paths.len() > 0 {
                let paths = env::join_paths(info.include_paths).unwrap();
                println!("cargo:include={}", paths.to_str().unwrap());
            }
            return;
        }
    }

    let libs_env = env::var("CUDNN_LIBS").ok();
    let libs = match libs_env {
        Some(ref v) => v.split(":").collect(),
        None => vec!["cudnn"]
    };

    let mode = if env::var_os("CUDNN_STATIC").is_some() {
    	"static"
    } else {
    	"dylib"
    };

    if let Some(lib_dir) = lib_dir {
    	println!("cargo:rustc-link-search=native={}", lib_dir);
    }
    
    for lib in libs {
        println!("cargo:rustc-link-lib={}={}", mode, lib);
    }

    if let Some(include_dir) = include_dir {
        println!("cargo:include={}", include_dir);
    }
}