defmodule Mix.Tasks.Exwrapper.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] -> round((inserts - sups) / files) + 5
      [files, inserts] -> round(inserts / files) + 5
      _ -> :rand.uniform(50)
    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
    Mix.Shell.IO.info(arg)
    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" ->
            value = String.to_integer(mineur) + 1
            case value < 255 do
              true -> [majeur, Integer.to_string(value), 0]
              false -> [majeur |> String.to_integer |> Kernel.+(1) |> Integer.to_string, 0, 0]
            end
          "bug" ->
            case new_correctfif(correctif) >= 255 do
              true -> [majeur, (mineur |> String.to_integer |> Kernel.+(1) |> Integer.to_string), 0]
              false -> [majeur, mineur, new_correctfif(correctif)]
            end
          _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

  defp new_readme do
    {:ok, raw} = File.read("README.md")
    {:ok, version} = File.read("VERSION")
    project_name = Mix.Project.config[:app]
      |> Atom.to_string
    n_raw = String.replace(raw, ~r/(\[\{\:#{project_name}\, \"\~\> .*\"\}\])/, "[{:#{project_name}, \"~> #{version |> String.trim}\"}]")
    File.write("README.md", n_raw)
  end

  defp exec do
    Mix.Task.get!(Clean).run([])
    Mix.Task.get!(Compile).run([])
    new_readme()
    {_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"])
  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()
            exec()
          true ->
            exec()
        end
    end
  end
end