defmodule Odinsea.Constants.Server do
  @moduledoc """
  Server constants ported from Java ServerConstants.
  These define the MapleStory client version and protocol details.
  """

  # MapleStory Client Version (GMS v342)
  @maple_version 342
  @maple_patch "1"
  @client_version 99

  # Protocol constants
  @packet_header_size 4
  @aes_key_size 32
  @block_size 1460

  # RSA Keys (from ServerConstants.java)
  @pub_key ""
  @maplogin_default "default"
  @maplogin_custom "custom"

  # Packet sequence constants
  @iv_length 4
  @short_size 2
  @int_size 4
  @long_size 8

  @doc """
  Returns the MapleStory client version.
  """
  def maple_version, do: @maple_version

  @doc """
  Returns the MapleStory patch version.
  """
  def maple_patch, do: @maple_patch

  @doc """
  Returns the full client version string.
  """
  def client_version, do: @client_version

  @doc """
  Returns the packet header size in bytes.
  """
  def packet_header_size, do: @packet_header_size

  @doc """
  Returns the AES key size in bytes.
  """
  def aes_key_size, do: @aes_key_size

  @doc """
  Returns the network block size.
  """
  def block_size, do: @block_size

  @doc """
  Returns the RSA public key.
  """
  def pub_key do
    Application.get_env(:odinsea, :rsa_pub_key, @pub_key)
  end

  @doc """
  Returns the default login background.
  """
  def maplogin_default, do: @maplogin_default

  @doc """
  Returns the custom login background.
  """
  def maplogin_custom, do: @maplogin_custom

  @doc """
  Returns the IV (initialization vector) length.
  """
  def iv_length, do: @iv_length

  @doc """
  Returns the size of a short in bytes.
  """
  def short_size, do: @short_size

  @doc """
  Returns the size of an int in bytes.
  """
  def int_size, do: @int_size

  @doc """
  Returns the size of a long in bytes.
  """
  def long_size, do: @long_size

  @doc """
  Returns server info from configuration.
  """
  def server_info do
    Application.get_env(:odinsea, :server, [])
  end

  @doc """
  Returns the server name.
  """
  def server_name do
    server_info()[:name] || "Luna"
  end

  @doc """
  Returns the server host.
  """
  def server_host do
    server_info()[:host] || "127.0.0.1"
  end

  @doc """
  Returns the server revision.
  """
  def server_revision do
    server_info()[:revision] || 1
  end
end