// requests.wren
foreign class Response {
  construct new() {}

  foreign isError
  foreign statusCode
  foreign body
  foreign json()
}

class Requests {
  // Foreign methods now expect a callback function.
  foreign static get_(url, headers, callback)
  foreign static post_(url, body, contentType, headers, callback)

  static get(url, headers, callback) {
    if (!(callback is Fn) || callback.arity != 2) {
      Fiber.abort("Callback must be a function that accepts 2 arguments: (error, response).")
    }
    get_(url, headers, callback)
  }

  static post(url, body, headers, callback) {
    if (!(callback is Fn) || callback.arity != 2) {
      Fiber.abort("Callback must be a function that accepts 2 arguments: (error, response).")
    }
    var contentType = headers != null && headers.containsKey("Content-Type") ?
        headers["Content-Type"] : "application/json"
    post_(url, body, contentType, headers, callback)
  }
}