use std::env;
use std::path::PathBuf;

const PDFIUM_URL: &str = "https://github.com/bblanchon/pdfium-binaries/releases/download/chromium%2F7725/pdfium-linux-x64.tgz";

#[expect(clippy::expect_used)]
#[expect(clippy::unwrap_used)]
#[expect(clippy::print_stderr)]
fn main() {
	println!("cargo:rerun-if-changed=build.rs");

	if env::var("CARGO_FEATURE_PDFIUM").is_err() {
		return;
	}

	let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());

	// OUT_DIR is target/<profile>/build/<pkg>-<hash>/out
	// Go up 3 levels to reach target/<profile>/
	let profile_dir = out_dir
		.ancestors()
		.nth(3)
		.expect("unexpected OUT_DIR structure")
		.to_path_buf();

	let lib_path = profile_dir.join("libpdfium.so");

	if !lib_path.exists() {
		let tgz_path = out_dir.join("pdfium.tgz");

		eprintln!("cargo:warning=Downloading PDFium from {PDFIUM_URL}");

		let status = std::process::Command::new("curl")
			.args(["-L", "--fail", "-o", tgz_path.to_str().unwrap(), PDFIUM_URL])
			.status()
			.expect("failed to run curl");
		assert!(status.success(), "curl failed to download PDFium");

		let status = std::process::Command::new("tar")
			.args([
				"-xzf",
				tgz_path.to_str().unwrap(),
				"-C",
				out_dir.to_str().unwrap(),
			])
			.status()
			.expect("failed to run tar");
		assert!(status.success(), "tar failed to extract PDFium");

		std::fs::copy(out_dir.join("lib").join("libpdfium.so"), &lib_path)
			.expect("failed to copy libpdfium.so");
	}

	println!("cargo:rustc-link-search=native={}", profile_dir.display());
	println!("cargo:rustc-link-lib=dylib=pdfium");
	println!("cargo:rustc-link-arg=-Wl,-rpath,$ORIGIN");
}