use glob::glob;
use std::{
    env,
    process::{Command, Stdio},
};

const CAPNP_VERSION: &str = "1.0.1"; // Keep in sync with scripts/install_capnp.sh
const PROTOC_VERSION: &str = "24.3"; // Keep in sync with scripts/install_protoc.sh

fn get_desired_capnp_version_string() -> String {
    CAPNP_VERSION.to_string()
}

fn get_desired_protoc_version_string() -> String {
    PROTOC_VERSION.to_string()
}

fn get_capnp_version_string() -> String {
    let output = Command::new("capnp")
        .arg("--version")
        .stdout(Stdio::piped())
        .output()
        .expect("capnp was not in the PATH");
    let s = String::from_utf8(output.stdout)
        .expect("'capnp --version' output was not a valid string")
        .trim()
        .to_owned();

    if !s.starts_with("Cap'n Proto version ") {
        panic!("invalid capnp version string: {}", s);
    }
    s[20..].to_owned()
}

fn get_protoc_version_string() -> String {
    let output = Command::new("protoc")
        .arg("--version")
        .stdout(Stdio::piped())
        .output()
        .expect("protoc was not in the PATH");
    let s = String::from_utf8(output.stdout)
        .expect("'protoc --version' output was not a valid string")
        .trim()
        .to_owned();

    if !s.starts_with("libprotoc ") {
        panic!("invalid protoc version string: {}", s);
    }
    s[10..].to_owned()
}

fn main() {
    if std::env::var("DOCS_RS").is_ok()
        || std::env::var("CARGO_CFG_DOC").is_ok()
        || std::env::var("BUILD_DOCS").is_ok()
    {
        return;
    }

    let desired_capnp_version_string = get_desired_capnp_version_string();
    let capnp_version_string = get_capnp_version_string();
    let desired_protoc_version_string = get_desired_protoc_version_string();
    let protoc_version_string = get_protoc_version_string();

    // Check capnp version
    let desired_capnp_major_version = desired_capnp_version_string
        .split_once('.')
        .unwrap()
        .0
        .parse::<usize>()
        .expect("should be valid int");

    if capnp_version_string
        .split_once('.')
        .unwrap()
        .0
        .parse::<usize>()
        .expect("should be valid int")
        != desired_capnp_major_version
    {
        panic!(
            "capnproto version should be major version 1, preferably {} but is {}",
            desired_capnp_version_string, capnp_version_string
        );
    } else if capnp_version_string != desired_capnp_version_string {
        println!(
            "cargo:warning=capnproto version may be untested: {}",
            capnp_version_string
        );
    }

    // Check protoc version
    let desired_protoc_major_version = desired_protoc_version_string
        .split_once('.')
        .unwrap()
        .0
        .parse::<usize>()
        .expect("should be valid int");
    if protoc_version_string
        .split_once('.')
        .unwrap()
        .0
        .parse::<usize>()
        .expect("should be valid int")
        < desired_protoc_major_version
    {
        panic!(
            "protoc version should be at least major version {} but is {}",
            desired_protoc_major_version, protoc_version_string
        );
    } else if protoc_version_string != desired_protoc_version_string {
        println!(
            "cargo:warning=protoc version may be untested: {}",
            protoc_version_string
        );
    }

    ::capnpc::CompilerCommand::new()
        .file("proto/veilid.capnp")
        .run()
        .expect("compiling schema");

    // Fix for missing __extenddftf2 on Android x86_64 Emulator
    let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap();
    // if target_os == "android" || target_os == "linux" {
    //     println!("cargo:rustc-link-lib=stdc++");
    // } else {
    //     println!("cargo:rustc-link-lib=c++");
    // }
    let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap();
    if target_arch == "x86_64" && target_os == "android" {
        let missing_library = "clang_rt.builtins-x86_64-android";
        let android_ndk_home = env::var("ANDROID_NDK_HOME").expect("ANDROID_NDK_HOME not set");
        let lib_path = glob(&format!("{android_ndk_home}/**/lib{missing_library}.a"))
            .expect("failed to glob")
            .next()
            .expect("Need libclang_rt.builtins-x86_64-android.a")
            .unwrap();
        let lib_dir = lib_path.parent().unwrap();
        println!("cargo:rustc-link-search={}", lib_dir.display());
        println!("cargo:rustc-link-lib=static={missing_library}");
    }
}