ex_ring_ring

defmodule ExRingRing.Infrastructure.HashAlgorithms do
  @moduledoc """
  Hash algorithms registry and factory.
  """
  @algorithms %{
    md5: ExRingRing.Infrastructure.HashAlgorithms.MD5,
    sha: ExRingRing.Infrastructure.HashAlgorithms.SHA,
    sha256: ExRingRing.Infrastructure.HashAlgorithms.SHA256,
    crc32: ExRingRing.Infrastructure.HashAlgorithms.CRC32,
    phash2: ExRingRing.Infrastructure.HashAlgorithms.PHash2
  }

  @doc """
  Gets the hash algorithm module.
  """
  @spec get_algorithm(atom()) :: module()
  def get_algorithm(algo) do
    Map.fetch!(@algorithms, algo)
  end

  @doc """
  Checks if algorithm is supported.
  """
  @spec supported?(atom()) :: boolean()
  def supported?(algo), do: Map.has_key?(@algorithms, algo)

  @doc """
  Gets list of supported algorithms.
  """
  @spec supported_algorithms() :: [atom()]
  def supported_algorithms, do: Map.keys(@algorithms)

  @doc """
  Calculates hash using the specified algorithm.
  """
  @spec hash(atom(), term()) :: non_neg_integer()
  def hash(algo, data) do
    get_algorithm(algo).hash(data)
  end

  @doc """
  Gets hash byte size for algorithm.
  """
  @spec hash_byte_size(atom()) :: pos_integer()
  def hash_byte_size(algo) do
    get_algorithm(algo).hash_byte_size()
  end
end