defmodule Pulsar.Socket do
  @doc """
  This module handles all socket-related operations.
  """

  defstruct socket: nil, ssl: false

  @type t :: %__MODULE__{
    socket: :gen_tcp.socket() | :ssl.sslsocket(),
    ssl: boolean()
  }

  @doc """
  Establishes a connection to the provided host.

  For more information about the available options, see `:ssl.connect/3` for ssl
  or `:gen_tcp.connect/3` for non ssl.
  """

  # connect("pulsar+ssl://istio-stagingmig.euw1-turtle.streamnative.g.snio.cloud:6651")
  def connect(uri, socket_opts \\ [:binary, nodelay: true, active: false, keepalive: true, verify: :verify_none]) do
    {host, port, ssl} = parse_uri(uri)

    socket = do_connect(host, port, socket_opts, ssl)
    %__MODULE__{socket: socket, ssl: ssl}
  end

  defp parse_uri(host) do
    uri = URI.parse(host)

    ssl  = (Map.get(uri, :scheme) == "pulsar+ssl")
    host = Map.get(uri, :host)
    port = Map.get(uri, :port, 6650)

    {host, port, ssl}
  end
  
  defp do_connect(host, port, socket_opts, ssl) do
    socket_module = socket_module(ssl)
    host = String.to_charlist(host)
    
    {:ok, socket} = apply(socket_module, :connect, [host, port, socket_opts, 5_000])
    socket
  end

  @doc """
  Closes the connection.
  """
  @spec close(__MODULE__.t()) :: :ok
  def close(%{socket: socket, ssl: ssl}), do: apply(socket_module(ssl), :close, [socket])

  defp socket_module(true), do: :ssl
  defp socket_module(false), do: :gen_tcp
end