use std::path::Path;
use std::process::Command;

fn run_npm(args: &[&str], web_dir: &Path) {
    let is_windows = cfg!(target_os = "windows");

    if is_windows {
        let mut cmd_args = vec!["/c", "npm"];
        cmd_args.extend_from_slice(args);
        let status = Command::new("cmd")
            .args(&cmd_args)
            .current_dir(web_dir)
            .status()
            .unwrap_or_else(|e| panic!("failed to spawn npm {}: {}", args.join(" "), e));

        if !status.success() {
            panic!("npm {} failed with status {}", args.join(" "), status);
        }
    } else {
        let status = Command::new("npm")
            .args(args)
            .current_dir(web_dir)
            .status()
            .unwrap_or_else(|e| panic!("failed to spawn npm {}: {}", args.join(" "), e));

        if !status.success() {
            panic!("npm {} failed with status {}", args.join(" "), status);
        }
    }
}

fn main() {
    println!("cargo:rerun-if-env-changed=SKIP_FRONTEND_BUILD");

    let web_dir = Path::new("web");
    if web_dir.exists() {
        println!("cargo:rerun-if-changed=web/src");
        println!("cargo:rerun-if-changed=web/index.html");
        println!("cargo:rerun-if-changed=web/package.json");
        println!("cargo:rerun-if-changed=web/vite.config.ts");
        println!("cargo:rerun-if-changed=web/tailwind.config.js");
        println!("cargo:rerun-if-changed=web/postcss.config.js");
        println!("cargo:rerun-if-changed=web/tsconfig.json");
    }

    if std::env::var("SKIP_FRONTEND_BUILD").is_ok() {
        println!("cargo:warning=SKIP_FRONTEND_BUILD is set, skipping frontend build");
        return;
    }

    if !web_dir.exists() {
        println!("cargo:warning=web/ directory not found, skipping frontend build");
        return;
    }

    println!("cargo:warning=building frontend (npm install)...");
    run_npm(&["install"], web_dir);

    println!("cargo:warning=building frontend (npm run build)...");
    run_npm(&["run", "build"], web_dir);

    println!("cargo:warning=frontend build complete, output in static/");
}