defmodule Mix.Tasks.OpenMercure.Publish do
  use Mix.Task

  defp diff(rawrep) do
    tab = rawrep
      |> String.trim
      |> String.split
      |> Enum.reject(fn x ->
        case Float.parse(x) do
          :error -> true
          _other -> false
        end
      end)
      |> Enum.map(&String.to_integer/1)
    case tab do
      [files, inserts, sups] ->
        a = round((inserts - sups) / files)
        round(rem(a*a, 255))
      [] -> :rand.uniform(255)
    end
  end

  defp new_correctfif(arg) do
    {rawrep, 0} = System.cmd("git", ["diff", "--shortstat"])
    String.to_integer(arg) + diff(rawrep)
  end

  @spec update_version :: :ok | {:error, String.t}
  defp update_version do
    case Mix.Shell.IO.prompt("Okay, the version updtable option is 'maj', 'min' or 'bug', what is your case ? ") |> String.trim do
      "maj" -> update_version("maj")
      "min" -> update_version("min")
      "bug" -> update_version("bug")
      _ -> update_version()
    end
  end

  @spec update_version(arg :: String.t) :: :ok | {:error, String.t}
  defp update_version(arg) do
    case File.read("VERSION") do
      {:ok, version} ->
        [majeur, mineur, correctif] = version
          |> String.trim
          |> String.split(".")
        new_version = case arg do
          "maj" -> [(majeur |> String.to_integer |> Kernel.+(1) |> Integer.to_string), 0, 0]
          "min" -> [majeur, (mineur |> String.to_integer |> Kernel.+(1) |> Integer.to_string), 0]
          "bug" -> [majeur, mineur, new_correctfif(correctif)]
          _other -> Mix.raise("argument must be 'min', 'maj', or 'bug'")
        end
        File.write("VERSION", Enum.join(new_version, "."))
      {:error, _reason} -> Mix.raise("File VERSION not exists !!")
    end

  end

  defp update_message do
    message = Mix.Shell.IO.prompt("What is your commit message: ") |> String.trim
    Mix.Shell.IO.info("The message for commit in git is '#{message}'.")
    case Mix.Shell.IO.yes?("Are you okay with that ? ") do
      true -> File.write(".message", message)
      false -> update_message()
    end
  end

  def run([arg, message]) do
    update_version(arg)
    {:ok, version} = File.read("VERSION")
    :ok = File.write(".message", message)
    Mix.Shell.IO.info("The new version of project is #{version}")
    case Mix.Shell.IO.yes?("Are you okay with that ?") do
      false ->
        update_version()
        run([arg, message])
      true ->
        Mix.Shell.IO.info("The message for commit in git is '#{message}'.")
        case Mix.Shell.IO.yes?("Are you okay with that ?") do
          false ->
            update_message()
            run([arg, File.read(".message")])
          true ->
            Mix.Task.get!(Clean).run([])
            Mix.Task.get!(Compile).run([])
            {_osef, 0} = System.cmd("git", ["add", "--all"])
            {_osef, 0} = System.cmd("git", ["commit", "-m", "#{{:ok, m} = File.read(".message"); m}"])
            {_osef, 0} = System.cmd("git", ["push"])
            Mix.Task.get!(Hex.Publish).run([])
        end
    end
  end
end