use anyhow::Result;

fn main() -> Result<()> {
    let is_docs_rs = std::env::var_os("DOCS_RS").is_some();


    if !is_docs_rs {
        let cuda_libs = std::env::var("CUDA_PATH").expect("CUDA_PATH not set");

        let libdebayer_lib = pkg_config::probe_library("libdebayer")?;

        let include_args: Vec<String> = libdebayer_lib.include_paths
            .iter()
            .map(|path| format!("-I{}", path.to_string_lossy()))
            .collect();

        let link_args: Vec<String> = libdebayer_lib.link_paths
            .iter()
            .map(|path| format!("-L{}", path.clone().into_os_string().into_string().unwrap()))
            .collect();

        let libs_args: Vec<String> = libdebayer_lib.libs
            .iter()
            .map(|path| format!("-l{}", path.to_string()))
            .collect();

        let mut clang_args = Vec::new();
        clang_args.extend(include_args);
        clang_args.extend(link_args);
        clang_args.extend(libs_args);

        let bindings = bindgen::Builder::default()
            .clang_args(clang_args)
            .header("wrapper.h")
            .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
            .default_enum_style(bindgen::EnumVariation::ModuleConsts)
            .size_t_is_usize(true)
            .generate()
            .expect("Unable to generate bindings");

        // Write the bindings to the $OUT_DIR/bindings.rs file.
        let out_path = std::path::PathBuf::from(std::env::var("OUT_DIR").unwrap());
        bindings
            .write_to_file(out_path.join("bindings.rs"))
            .expect("Couldn't write bindings!");

        for path in libdebayer_lib.link_paths {
            println!("cargo:rustc-link-search={}", path.clone().into_os_string().into_string().unwrap());
        }

        for l in libdebayer_lib.libs {
            println!("cargo:rustc-link-lib={}", l.to_string());
        }

        println!("cargo:rustc-link-search={}", cuda_libs);
        println!("cargo:rustc-link-lib=cudart");
    } else {
        let mut clang_args = Vec::new();
        
        clang_args.push("-Idoc-headers");
        let bindings = bindgen::Builder::default()
            .clang_args(clang_args)
            .header("wrapper.h")
            .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
            .default_enum_style(bindgen::EnumVariation::ModuleConsts)
            .size_t_is_usize(true)
            .generate()
            .expect("Unable to generate bindings");

        // Write the bindings to the $OUT_DIR/bindings.rs file.
        let out_path = std::path::PathBuf::from(std::env::var("OUT_DIR").unwrap());
        bindings
            .write_to_file(out_path.join("bindings.rs"))
            .expect("Couldn't write bindings!");
    }
    
    Ok(())
}