defmodule Mv.ConfigSmtpTest do
  @moduledoc """
  Unit tests for Mv.Config SMTP-related helpers.

  ENV overrides Settings (same pattern as OIDC/Vereinfacht). Uses real ENV and
  Settings; no mocking so we test the actual precedence. async: false because
  we mutate ENV.
  """
  use Mv.DataCase, async: false

  describe "smtp_host/0" do
    test "returns ENV value when SMTP_HOST is set" do
      set_smtp_env("SMTP_HOST", "smtp.example.com")
      assert Mv.Config.smtp_host() == "smtp.example.com"
    after
      clear_smtp_env()
    end

    test "returns nil when SMTP_HOST is not set and Settings have no smtp_host" do
      clear_smtp_env()
      assert Mv.Config.smtp_host() == nil
    end
  end

  describe "smtp_port/0" do
    test "returns parsed integer when SMTP_PORT ENV is set" do
      set_smtp_env("SMTP_PORT", "587")
      assert Mv.Config.smtp_port() == 587
    after
      clear_smtp_env()
    end

    test "returns nil or default when SMTP_PORT is not set" do
      clear_smtp_env()
      port = Mv.Config.smtp_port()
      assert port == nil or (is_integer(port) and port in [25, 465, 587])
    end
  end

  describe "smtp_configured?/0" do
    test "returns true when smtp_host is present (from ENV or Settings)" do
      set_smtp_env("SMTP_HOST", "smtp.example.com")
      assert Mv.Config.smtp_configured?() == true
    after
      clear_smtp_env()
    end

    test "returns false when no SMTP host is set" do
      clear_smtp_env()
      refute Mv.Config.smtp_configured?()
    end
  end

  describe "smtp_env_configured?/0" do
    test "returns true when any SMTP ENV variable is set" do
      set_smtp_env("SMTP_HOST", "smtp.example.com")
      assert Mv.Config.smtp_env_configured?() == true
    after
      clear_smtp_env()
    end

    test "returns false when no SMTP ENV variables are set" do
      clear_smtp_env()
      refute Mv.Config.smtp_env_configured?()
    end
  end

  describe "smtp_password/0 and SMTP_PASSWORD_FILE" do
    test "returns value from SMTP_PASSWORD when set" do
      set_smtp_env("SMTP_PASSWORD", "env-secret")
      assert Mv.Config.smtp_password() == "env-secret"
    after
      clear_smtp_env()
    end

    test "returns content of file when SMTP_PASSWORD_FILE is set and SMTP_PASSWORD is not" do
      clear_smtp_env()
      path = Path.join(System.tmp_dir!(), "mv_smtp_test_#{System.unique_integer([:positive])}")
      File.write!(path, "file-secret\n")
      Process.put(:smtp_password_file_path, path)
      set_smtp_env("SMTP_PASSWORD_FILE", path)
      assert Mv.Config.smtp_password() == "file-secret"
    after
      clear_smtp_env()
      if path = Process.get(:smtp_password_file_path), do: File.rm(path)
    end

    test "SMTP_PASSWORD overrides SMTP_PASSWORD_FILE when both are set" do
      path = Path.join(System.tmp_dir!(), "mv_smtp_test_#{System.unique_integer([:positive])}")
      File.write!(path, "file-secret")
      Process.put(:smtp_password_file_path, path)
      set_smtp_env("SMTP_PASSWORD_FILE", path)
      set_smtp_env("SMTP_PASSWORD", "env-wins")
      assert Mv.Config.smtp_password() == "env-wins"
    after
      clear_smtp_env()
      if path = Process.get(:smtp_password_file_path), do: File.rm(path)
    end
  end

  describe "smtp_*_env_set?/0" do
    test "smtp_host_env_set? returns true when SMTP_HOST is set" do
      set_smtp_env("SMTP_HOST", "x")
      assert Mv.Config.smtp_host_env_set?() == true
    after
      clear_smtp_env()
    end

    test "smtp_password_env_set? returns true when SMTP_PASSWORD or SMTP_PASSWORD_FILE is set" do
      set_smtp_env("SMTP_PASSWORD", "x")
      assert Mv.Config.smtp_password_env_set?() == true
    after
      clear_smtp_env()
    end
  end

  defp set_smtp_env(key, value) do
    System.put_env(key, value)
  end

  defp clear_smtp_env do
    System.delete_env("SMTP_HOST")
    System.delete_env("SMTP_PORT")
    System.delete_env("SMTP_USERNAME")
    System.delete_env("SMTP_PASSWORD")
    System.delete_env("SMTP_PASSWORD_FILE")
    System.delete_env("SMTP_SSL")
  end
end