defmodule Bugsnag do
  use Application

  alias Bugsnag.Payload

  @notify_url "https://notify.bugsnag.com"
  @request_headers [{"Content-Type", "application/json"}]

  def start(_type, _args) do
    config = Keyword.merge default_config, Application.get_all_env(:bugsnag)

    if config[:use_logger] do
      :error_logger.add_report_handler(Bugsnag.Logger)
    end

    # put normalized api key to application config
    Application.put_env(:bugsnag, :api_key, config[:api_key])
  end

  def report(exception, options \\ []) do
    stacktrace = options[:stacktrace] || System.stacktrace

    spawn fn ->
      Payload.new(exception, stacktrace, options)
        |> to_json
        |> send_notification
    end
  end

  def to_json(payload) do
    payload |> Poison.encode!
  end

  defp send_notification(body) do
    HTTPoison.post @notify_url, body, @request_headers
  end

  defp default_config do
    [
      api_key: System.get_env("BUGSNAG_API_KEY") || "FAKEKEY",
      use_logger: true
    ]
  end
end