fn doit(ctx: &ducc::Ducc, code: &str) { ctx.compile(code, None).unwrap().call::<(), ()>(()).unwrap(); }

fn get_string(str: ducc::Value) -> String { str.as_string().unwrap().to_string().unwrap() }

fn main() {
  let ctx = ducc::Ducc::new();

  /* initialize */
  doit(&ctx, "var global = (function(){ return this; }).call(null);");

  /* load library */
  {
    doit(&ctx, include_str!("shim.min.js"));
    doit(&ctx, include_str!("xlsx.full.min.js"));
  }

  /* get version string */
  {
    let vers: ducc::Value = ctx.compile("XLSX.version", None).unwrap().call(()).unwrap();
    println!("SheetJS library version {}", get_string(vers));
  }

  /* read file */
  {
    let mut iter = std::env::args();
    let path: String = iter.nth(1).expect("must specify a file name");

    let file: Vec<u8> = std::fs::read(path.clone()).unwrap();

    /* push data to duktape (creates a Uint8Array) */
    let bytes = ctx.create_bytes(file.as_slice()).unwrap();

    /* assign to global `buf` */
    let _ = ctx.globals().set("buf", bytes);
  }

  /* parse workbook */
  {
    doit(&ctx, "wb = XLSX.read(buf.slice(0, buf.length), {type:'buffer'});");
    doit(&ctx, "ws = wb.Sheets[wb.SheetNames[0]]");
  }

  /* print CSV */
  {
    let csv: ducc::Value = ctx.compile("XLSX.utils.sheet_to_csv(ws)", None).unwrap().call(()).unwrap();
    println!("{}", get_string(csv));
  }
  
  /* write file */
  {
    /* due to issues with the duktape crate, it is easier to pass a base64-encoded string and decode in Rust */
    let xlsb: ducc::Value = ctx.compile("XLSX.write(wb, {type:'base64', bookType:'xlsb'})", None).unwrap().call(()).unwrap();
    let _ = std::fs::write("sheetjsw.xlsb", base64::Engine::decode(&base64::engine::general_purpose::STANDARD, get_string(xlsb)).unwrap());
  }
}