defmodule TermuxSmsCli.Fetcher do
  use GenServer

  defp fetch_int(filter_fn, minimum) do
    fetch_int(filter_fn, minimum, minimum)
  end

  defp fetch_int(filter_fn, minimum, count) do
    {reply, 0} = System.cmd("ssh", ["192.168.2.8", "-p", "8022", "termux-sms-list", "-l", "#{count}"])
    reply = Jason.decode!(reply)
    reply = Enum.filter(reply, filter_fn)
    if (Enum.count(reply) < minimum) do
      fetch_int(filter_fn, minimum, 2*count)
    else
      reply
    end
  end

  def start_link(opts) do
    GenServer.start_link(__MODULE__, :ok, opts)
  end

  def init(:ok) do
    {:ok, nil}
  end

  def handle_call({:fetch, count}, _From, nil) do
    {:reply, fetch_int(fn _ -> true end, count), nil}
  end

  def handle_call({:fetch_thread, count, tid}, _From, nil) do
    {:reply, fetch_int(fn %{"threadid" => tid_} -> tid == tid_ end, count), nil}
  end

  def fetch(pid, count) do
    GenServer.call(pid, {:fetch, count})
  end

  def fetch_thread(pid, count, tid) do
    GenServer.call(pid, {:fetch_thread, count, tid})
  end
end