import gleam/dynamic
import gleam/iterator
import gleam/result

@external(erlang, "io", "get_line")
@external(javascript, "./js_ffi.mjs", "read_line")
fn ffi_read_line(prompt: String) -> dynamic.Dynamic

fn read_line() -> Result(String, Nil) {
  ffi_read_line("")
  |> dynamic.from()
  |> dynamic.string()
  |> result.nil_error()
}

pub fn stdin() -> iterator.Iterator(String) {
  iterator.repeatedly(read_line)
  |> iterator.take_while(fn(it) {
    case it {
      Ok(_) -> True
      Error(_) -> False
    }
  })
  |> iterator.map(fn(it) {
    let assert Ok(line) = it
    line
  })
}

import gleam/io

pub fn main() {
  stdin()
  |> iterator.to_list
  |> io.debug
}